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GATA2 deficiency is a bone marrow failure syndrome effectively treated with hematopoietic cell transplantation (HCT), which also addresses the predisposition to many infections (prominently mycobacterial). However, many GATA2-deficient persons who come to HCT also have prevalent and refractory human papilloma virus disease (HPVD), which can be a precursor to cancer. We analyzed 75 HCT recipients for the presence of HPVD to identify patient characteristics and transplantation results that influence HPVD outcomes. We assessed the impact of cellular recovery and iatrogenic post-transplantation immunosuppression, as per protocol (PP) or intensified/prolonged (IP) graft-versus-host disease (GVHD) prophylaxis or treatment, on the persistence or resolution of HPVD. Our experience with 75 HCT recipients showed a prevalence of 49% with anogenital HPVD, which was either a contributing or primary factor in the decision to proceed to HCT. Of 24 recipients with sufficient follow-up, 13 had resolution of HPVD, including 8 with IP and 5 with PP. Eleven recipients had persistent HPVD, including 5 with IP and 6 with PP immunosuppression. No plausible cellular recovery group (natural killer cells or T cells) showed a significant difference in HPV outcomes. One recipient died of metastatic squamous cell carcinoma, presumably of anogenital origin, at 33 months post-transplantation after prolonged immunosuppression for chronic GVHD. Individual cases demonstrate the need for continued aggressive monitoring, especially in the context of disease prevalent at transplantation or prior malignancy. HCT proved curative in many cases in which HPVD was refractory and recurrent prior to transplantation, supporting a recommendation that HPVD should be considered an indication rather than contraindication to HCT, but post-transplantation monitoring should be prolonged with a high level of vigilance for new or recurrent HPVD.

Lessons Learned Despite the initial optimism for using immune checkpoint inhibition in the treatment of multiple myeloma, subsequent clinical studies have been disappointing. Preclinical studies have suggested that priming the immune system with various modalities in addition to checkpoint inhibition may overcome the relative T-cell exhaustion or senescence; however, in this small data set, radiotherapy with checkpoint inhibition did not appear to activate the antitumor immune response. Background Extramedullary disease (EMD) is recognized as an aggressive subentity of multiple myeloma (MM) with a need for novel therapeutic approaches. We therefore designed a proof-of-principle pilot study to evaluate the synergy between the combination of the anti–PD-L1, avelumab, and concomitant hypofractionated radiotherapy. Methods This was a single-arm phase II Simon two-stage single center study that was prematurely terminated because of the COVID-19 pandemic after enrolling four patients. Key eligibility included patients with relapsed/refractory multiple myeloma (RRMM) who had exhausted or were not candidates for standard therapy and had at least one lesion amenable to radiotherapy. Patients received avelumab until progression or intolerable toxicity and hypofractionated radiotherapy to a focal lesion in cycle 2. Radiotherapy was delayed until cycle 2 to allow the avelumab to reach a study state, given the important observation from previous studies that concomitant therapy is needed for the abscopal effect. Results At a median potential follow-up of 10.5 months, there were no objective responses, one minimal response, and two stable disease as best response. The median progression-free survival (PFS) was 5.3 months (95% confidence interval [CI]: 2.5–7.1 months), and no deaths occurred. There were no grade ≥3 and five grade 1–2 treatment-related adverse events. Conclusion Avelumab in combination with radiotherapy for patients with RRMM and EMD was associated with very modest systemic clinical benefit; however, patients did benefit as usual from local radiotherapy. Furthermore, the combination was very well tolerated compared with historical RRMM treatment regimens.

Background Most patients infected with Epstein-Barr virus (EBV) are asymptomatic, have nonspecific symptoms, or have self-limiting infectious mononucleosis. EBV, however, may result in severe primary disease or cancer. Methods We report EBV diseases associated with GATA2 deficiency at one institution and describe the hematology, virology, and cytokine findings. Results Seven patients with GATA2 deficiency developed severe EBV disease. Three presented with EBV infectious mononucleosis requiring hospitalization, 1 had chronic active EBV disease (B-cell type), 1 had EBV-associated hydroa vacciniforme-like lymphoma with hemophagocytic lymphohistiocytosis, and 2 had EBV-positive smooth muscle tumors. Four of the 7 patients had severe warts and 3 had disseminated nontuberculous mycobacterial infections. All of the patients had low numbers of monocytes, B cells, CD4 T cells, and natural killer cells. All had elevated levels of EBV in the blood; 2 of 3 patients tested had expression of the EBV major immediate-early gene in the blood indicative of active EBV lytic infection. Mean plasma levels of tumor necrosis factor α, interferon γ, and interferon gamma-induced protein 10 were higher in patients with GATA2 deficiency than in controls. Conclusions GATA2 is the first gene associated with EBV hydroa vacciniforme-like lymphoma. GATA2 deficiency should be considered in patients with severe primary EBV infection or EBV-associated cancer, especially in those with disseminated nontuberculous mycobacterial disease and warts.

The incidence and importance of bone marrow involvement and/or early bone lesions in multiple myeloma (MM) precursor diseases is largely unknown. This study prospectively compared the sensitivity of several imaging modalities in monoclonal gammopathy of undetermined significance (MGUS), smoldering multiple myeloma (SMM) and MM. Thirty patients (10 each with MGUS, SMM and MM) were evaluated with skeletal survey, [18F]FDG-PET/CT, [18F]NaF-PET/CT and morphologic dynamic contrast enhanced (DCE)-MRI. An additional 16 SMM patients had skeletal surveys and FDG-PET/CT. Among MGUS patients, DCE-MRI found only one focal marrow abnormality; other evaluations were negative. Among 26 SMM patients, five (19%) were re-classified as MM based on lytic bone lesions on CT and six had unifocal or diffuse marrow abnormality. Among MM, marrow abnormalities were observed on FDG-PET/CT in 8/10 patients and on DCE-MRI in nine evaluable patients. Abnormal NaF uptake was observed only in MM patients with lytic lesions on CT, providing no additional clinical information.

Purpose: Chronic lymphocytic leukemia (CLL) cells depend on microenvironmental interactions for proliferation and survival that are at least partially mediated through B-cell receptor (BCR) signaling. Ibrutinib, a Bruton tyrosine kinase inhibitor, disrupts BCR signaling and leads to the egress of tumor cells from the microenvironment. Although the on-target effects on CLL cells are well defined, the impact on the microenvironment is less well studied. We therefore sought to characterize the in vivo effects of ibrutinib on the tumor microenvironment. Experimental Design: Patients received single-agent ibrutinib on an investigator-initiated phase II trial. Serial blood and tissue samples were collected pretreatment and during treatment. Changes in cytokine levels, cellular subsets, and microenvironmental interactions were assessed. Results: Serum levels of key chemokines and inflammatory cytokines decreased significantly in patients on ibrutinib. Furthermore, ibrutinib treatment decreased circulating tumor cells and overall T-cell numbers. Most notably, a reduced frequency of the Th17 subset of CD4+ T cells was observed concurrent with reduced expression of activation markers and PD-1 on T cells. Consistent with direct inhibition of T cells, ibrutinib inhibited Th17 differentiation of murine CD4+ T cells in vitro. Finally, in the bone marrow microenvironment, we found that ibrutinib disaggregated the interactions of macrophages and CLL cells, inhibited secretion of CXCL13, and decreased the chemoattraction of CLL cells. Conclusions: In conjunction with inhibition of BCR signaling, these changes in the tumor microenvironment likely contribute to the antitumor activity of ibrutinib and may impact the efficacy of immunotherapeutic strategies in patients with CLL. Clin Cancer Res; 22(7); 1572–82. ©2015 AACR. See related commentary by Bachireddy and Wu, p. 1547

Eltrombopag (EPAG) received approval from the US Food and Drug Administration for the treatment of refractory severe aplastic anemia (rSAA) based on treatment of 43 patients with doses escalating from 50 to 150 mg daily for 12 weeks. Response kinetics suggested that more prolonged administration of EPAG at a dose of 150 mg could speed and improve response rates. We enrolled 40 patients with rSAA in a study of EPAG 150 mg daily, with a primary end point of response at 24 weeks. Twenty (50%) of 40 patients responded at 24 weeks; 5 (25%) of 20 would have been deemed nonresponders at 12 weeks, the end point of the previous study. Fifteen of the 19 responding patients continuing on EPAG had drug discontinued for robust response; 5 of the 15 required EPAG re-initiation for relapse, with all recovering response. To analyze risk of clonal progression, we combined long-term data from the 83 patients with rSAA enrolled in both studies. Evolution to an abnormal karyotype occurred in 16 (19%), most within 6 months of EPAG initiation. Targeted deep sequencing/whole-exome sequencing was performed pre-EPAG and at primary response end point and/or time of clonal evolution or longest follow-up. Cytogenetic evolution did not correlate with mutational status, and overall mutated allele fractions of myeloid cancer genes did not increase on EPAG. In summary, extended administration of EPAG at a dose of 150 mg for 24 weeks rescued responses in some patients with rSAA not responding at 12 weeks. The temporal relationship between clonal evolution and drug exposure suggests that EPAG may promote expansion of dormant preexisting clones with an aberrant karyotype. The studies were registered at www.clinicaltrials.gov as #NCT00922883 and #NCT01891994.

GATA2 deficiency is an immunodeficiency and bone marrow failure disorder caused by pathogenic variants in GATA2. It is inherited in an autosomal-dominant pattern or can be due to de novo sporadic germline mutation. Patients commonly have B-cell, dendritic cell, natural killer cell, and monocytopenias, and are predisposed to myelodysplastic syndrome, acute myeloid leukemia, and chronic myelomonocytic leukemia. Patients may suffer from disseminated human papilloma virus and mycobacterial infections, pulmonary alveolar proteinosis, and lymphedema. The bone marrow eventually takes on a characteristic hypocellular myelodysplasia with loss of monocytes and hematogones, megakaryocytes with separated nuclear lobes, micromegakaryocytes, and megakaryocytes with hypolobated nuclei.

International audience; Ikaros/IKZF1 is an essential transcription factor expressed throughout hematopoiesis. IKZF1 is implicated in lymphocyte and myeloid differentiation and negative regulation of cell proliferation. In humans, somatic mutations in IKZF1 have been linked to the development of B cell acute lymphoblastic leukemia (ALL) in children and adults. Recently, heterozygous germline IKZF1 mutations have been identified in patients with a B cell immune deficiency mimicking common variable immunodeficiency. These mutations demonstrated incomplete penetrance and led to haploinsufficiency. Herein, we report 7 unrelated patients with a novel early-onset combined immunodeficiency associated with de novo germline IKZF1 heterozygous mutations affecting amino acid N159 located in the DNA-binding domain of IKZF1. Different bacterial and viral infections were diagnosed, but Pneumocystis jirovecii pneumonia was reported in all patients. One patient developed a T cell ALL. This immunodeficiency was characterized by innate and adaptive immune defects, including low numbers of B cells, neutrophils, eosinophils, and myeloid dendritic cells, as well as T cell and monocyte dysfunctions. Notably, most T cells exhibited a naive phenotype and were unable to evolve into effector memory cells. Functional studies indicated these mutations act as dominant negative. This defect expands the clinical spectrum of human IKZF1-associated diseases from somatic to germline, from haploinsufficient to dominant negative.

Enumeration of blasts in the bone marrow is critical for diagnostic, prognostic, and therapeutic response evaluation in myelodysplastic syndromes, myeloproliferative neoplasms and acute leukemias. However, few studies have examined the accuracy and precision of marrow blast counting using standard microscopic procedures. In our study, 4 experienced hematopathologists evaluated blast percentages in marrow using either differential counts on aspirate smears or visual estimates on CD34-stained trephine biopsies. Results of an independent observer's manual counts of individual labeled and unlabeled cells performed on high resolution digital images of CD34-stained trephine biopsies were designated as the "Digital Reference." Hematopathologists' blast counts showed excellent interobserver reproducibility, but the counts in smears and trephine biopsies correlated poorly with each other. Compared to the Digital Reference, both smear and trephine evaluations showed positive bias and high variability. The biopsy showed less variability but higher positive bias relative to the smears, indicating that counts were overestimated more in the hematopathologists' biopsy evaluation. Flow cytometric counts correlated well with the Digital Reference, and cases with high blast count generally showed worse cytogenetic findings. Our results demonstrate the need for better counting methods if significant decisions are made based on microscopic enumeration of blasts. Further efforts should be made to develop markers to better define blast cells and perhaps incorporate automated digital imaging technologies to enumerate them. Also, consideration should be given to quantifying blasts per marrow area in biopsies instead of per nucleated cells.

The absence of cancer-restricted surface markers is a major impediment to antigen-specific immunotherapy using chimeric antigen receptor (CAR) T cells. For example, targeting the canonical myeloid marker CD33 in acute myeloid leukemia (AML) results in toxicity from destruction of normal myeloid cells. We hypothesized that a leukemia-specific antigen could be created by deleting CD33 from normal hematopoietic stem and progenitor cells (HSPCs), thereby generating a hematopoietic system resistant to CD33-targeted therapy and enabling specific targeting of AML with CAR T cells. We generated CD33-deficient human HSPCs and demonstrated normal engraftment and differentiation in immunodeficient mice. Autologous CD33 KO HSPC transplantation in rhesus macaques demonstrated long-term multilineage engraftment of gene-edited cells with normal myeloid function. CD33-deficient cells were impervious to CD33-targeting CAR T cells, allowing for efficient elimination of leukemia without myelotoxicity. These studies illuminate a novel approach to antigen-specific immunotherapy by genetically engineering the host to avoid on-target, off-tumor toxicity.

BACKGROUND. Monogenic IFN–mediated autoinflammatory diseases present in infancy with systemic inflammation, an IFN response gene signature, inflammatory organ damage, and high mortality. We used the JAK inhibitor baricitinib, with IFN-blocking activity in vitro, to ameliorate disease. METHODS. Between October 2011 and February 2017, 10 patients with CANDLE (chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperatures), 4 patients with SAVI (stimulator of IFN genes–associated [STING-associated] vasculopathy with onset in infancy), and 4 patients with other interferonopathies were enrolled in an expanded access program. The patients underwent dose escalation, and the benefit was assessed by reductions in daily disease symptoms and corticosteroid requirement. Quality of life, organ inflammation, changes in IFN-induced biomarkers, and safety were longitudinally assessed. RESULTS. Eighteen patients were treated for a mean duration of 3.0 years (1.5–4.9 years). The median daily symptom score decreased from 1.3 (interquartile range [IQR], 0.93–1.78) to 0.25 (IQR, 0.1–0.63) (P < 0.0001). In 14 patients receiving corticosteroids at baseline, daily prednisone doses decreased from 0.44 mg/kg/day (IQR, 0.31–1.09) to 0.11 mg/kg/day (IQR, 0.02–0.24) (P < 0.01), and 5 of 10 patients with CANDLE achieved lasting clinical remission. The patients’ quality of life and height and bone mineral density Z-scores significantly improved, and their IFN biomarkers decreased. Three patients, two of whom had genetically undefined conditions, discontinued treatment because of lack of efficacy, and one CANDLE patient discontinued treatment because of BK viremia and azotemia. The most common adverse events were upper respiratory infections, gastroenteritis, and BK viruria and viremia. CONCLUSION. Upon baricitinib treatment, clinical manifestations and inflammatory and IFN biomarkers improved in patients with the monogenic interferonopathies CANDLE, SAVI, and other interferonopathies. Monitoring safety and efficacy is important in benefit-risk assessment. TRIAL REGISTRATION. ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT01724580","term_id":"NCT01724580"}}NCT01724580 and {"type":"clinical-trial","attrs":{"text":"NCT02974595","term_id":"NCT02974595"}}NCT02974595. FUNDING. This research was supported by the Intramural Research Program of the NIH, NIAID, and NIAMS. Baricitinib was provided by Eli Lilly and Company, which is the sponsor of the expanded access program for this drug.

The safety and efficacy of ibrutinib (420 mg) in chronic lymphocytic leukemia (CLL) were evaluated in a phase 2 study; 51 patients had TP53 aberration (TP53 cohort) and 35 were enrolled because of age 65 years or older (elderly cohort). Both cohorts included patients with treatment-naive (TN) and relapsed/refractory (RR) CLL. With the median follow-up of 4.8 years, 49 (57.0%) of 86 patients remain on study. Treatment was discontinued for progressive disease in 20 (23.3%) patients and for adverse events in 5 (5.8%). Atrial fibrillation occurred in 18 (20.9%) patients for a rate of 6.4 per 100 patient-years. No serious bleeding occurred. The overall response rate at 6 months, the primary study endpoint, was 95.8% for the TP53 cohort (95% confidence interval, 85.7%-99.5%) and 93.9% for the elderly cohort (95% confidence interval, 79.8%-99.3%). Depth of response improved with time: at best response, 14 (29.2%) of 48 patients in the TP53 cohort and 9 (27.3%) of 33 in the elderly cohort achieved a complete response. Median minimal residual disease (MRD) in peripheral blood was 3.8 × 10-2 at 4 years, with MRD-negative (

Myelodysplastic/myeloproliferative neoplasms (MDS/MPN) are clonal hematopoietic disorders with myeloproliferative features, varying degrees of dysplasia and cytopenias, and increased propensity for progression to acute myeloid leukemia (AML). MDS/MPN are uncommon in the pediatric age group, and best exemplified by Juvenile myelomonocytic leukemia (JMML), a rare but aggressive leukemia of early childhood. Remarkable progress has been made in understanding the genetic basis of JMML leading to improved diagnostic criteria and better management. It is now understood that JMML is associated with somatic or germ line mutations in NF1, NRAS, KRAS, PTPN11, and CBL in greater than 90 % of cases with the common downstream mechanism being uncontrolled activation of the RAS/MAPK pathway. More recently, KRAS and NRAS mutations have also been identified in RAS-associated autoimmune leukoproliferative disorder (RALD), which shares some clinical, hematopathological, and genetic features with JMML, but has an indolent clinical course. Hematopoietic stem cell transplant (HSCT) is currently the only curative therapy for JMML, although newer therapeutic agents are currently in clinical trials. This review will focus primarily on the current clinical features, diagnostic criteria, pathologic features, and therapy of JMML and provide a brief description of RALD.

Ras-associated autoimmune leukoproliferative disorder (RALD) is a chronic, nonmalignant condition that presents with persistent monocytosis and is often associated with leukocytosis, lymphoproliferation, and autoimmune phenomena. RALD has clinical and laboratory features that overlap with those of juvenile myelomonocytic leukemia (JMML) and chronic myelomonocytic leukemia (CMML), including identical somatic mutations in KRAS or NRAS genes noted in peripheral blood mononuclear cells. Long-term follow-up of these patients suggests that RALD has an indolent clinical course whereas JMML is fatal if left untreated. Immunophenotyping peripheral blood from RALD patients shows characteristic circulating activated monocytes and polyclonal CD10+ B cells. Distinguishing RALD from JMML and CMML has implications for clinical care and prognosis.

SummaryChromothripsis is a catastrophic cellular event recently described in cancer in which chromosomes undergo massive deletion and rearrangement. Here, we report a case in which chromothripsis spontaneously cured a patient with WHIM syndrome, an autosomal dominant combined immunodeficiency disease caused by gain-of-function mutation of the chemokine receptor CXCR4. In this patient, deletion of the disease allele, CXCR4R334X, as well as 163 other genes from one copy of chromosome 2 occurred in a hematopoietic stem cell (HSC) that repopulated the myeloid but not the lymphoid lineage. In competitive mouse bone marrow (BM) transplantation experiments, Cxcr4 haploinsufficiency was sufficient to confer a strong long-term engraftment advantage of donor BM over BM from either wild-type or WHIM syndrome model mice, suggesting a potential mechanism for the patient’s cure. Our findings suggest that partial inactivation of CXCR4 may have general utility as a strategy to promote HSC engraftment in transplantation.

IL-6 activity in normal plasma cells (nPCs) and abnormal plasma cells (aPCs) is CD126 (subunit of IL-6 receptor) dependent. We quantified CD126 expression on nPCs and aPCs in monoclonal gammopathy of undetermined significance (MGUS), smoldering myeloma (SMM), and multiple myeloma (MM). CD126 was detected on all nPCs and aPCs indicating that CD126 does not have diagnostic utility. CD126 expression was higher in aPCs than in nPCs in 85% SMM but only 41% MGUS and there was evidence that CD126 was higher in aPCs than nPCs in the SMM (p = .048) but not MGUS (p = .96) patients. There is also a greater association between nPC and aPC CD126 expression in low risk MGUS than observed in high risk MGUS and SMM, suggesting normal regulation of CD126 decreases with disease progression. Future studies need to elucidate the role of bone marrow milieu versus escape from normal CD126 regulation in malignant transformation of clonal plasma cells.

Acquired aplastic anemia results from immune-mediated destruction of bone marrow. Immunosuppressive therapies are effective, but reduced numbers of residual stem cells may limit their efficacy. In patients with aplastic anemia that was refractory to immunosuppression, eltrombopag, a synthetic thrombopoietin-receptor agonist, led to clinically significant increases in blood counts in almost half the patients. We combined standard immunosuppressive therapy with eltrombopag in previously untreated patients with severe aplastic anemia.We enrolled 92 consecutive patients in a prospective phase 1-2 study of immunosuppressive therapy plus eltrombopag. The three consecutively enrolled cohorts differed with regard to the timing of initiation and the duration of the eltrombopag regimen (cohort 1 received eltrombopag from day 14 to 6 months, cohort 2 from day 14 to 3 months, and cohort 3 from day 1 to 6 months). The cohorts were analyzed separately. The primary outcome was complete hematologic response at 6 months. Secondary end points included overall response, survival, relapse, and clonal evolution to myeloid cancer.The rate of complete response at 6 months was 33% in cohort 1, 26% in cohort 2, and 58% in cohort 3. The overall response rates at 6 months were 80%, 87%, and 94%, respectively. The complete and overall response rates in the combined cohorts were higher than in our historical cohort, in which the rate of complete response was 10% and the overall response rate was 66%. At a median follow-up of 2 years, the survival rate was 97%; one patient died during the study from a nonhematologic cause. Marked increases in bone marrow cellularity, CD34+ cell number, and frequency of early hematopoietic progenitors were noted. Rates of relapse and clonal evolution were similar to our historical experience. Severe rashes occurred in two patients, resulting in the early discontinuation of eltrombopag.The addition of eltrombopag to immunosuppressive therapy was associated with markedly higher rates of hematologic response among patients with severe aplastic anemia than in a historical cohort. (Funded by the National Heart, Lung, and Blood Institute; ClinicalTrials.gov number, NCT01623167 .).

Patients with germline mutations in PIK3CD, immunodeficiency, lymphoproliferation, and autoimmunity show a distinct pattern of abnormal B-cell maturation in the bone marrow.

Currently, no reliable biomarkers are available to predict transformation from smoldering myeloma (SMM) to multiple myeloma (MM). Using an ultrasensitive enzyme-linked immunosorbent assay (ELISA) we assessed the levels of a broad range of cytokines and chemokines in the peripheral blood (PB) and bone marrow (BM) supernatant collected from 14 SMM and 38 MM patients and compared to healthy donors. We found significantly increased levels of key cytokines, in particular CXCL8 (IL-8), associated with progressive disease state (controls→SMM→MM). Cytokine profiles were found similar in PB and BM. Five of fourteen SMM patients (36%) progressed to MM. Our findings, although based on a limited number of patients, suggest that serum-based cytokines may have a future role as biomarkers for disease progression and could potentially be assessed as novel targets for treatment.

Genetic defects in MOGS, the gene encoding mannosyl-oligosaccharide glucosidase (the first enzyme in the processing pathway of N-linked oligosaccharide), cause the rare congenital disorder of glycosylation type IIb (CDG-IIb), also known as MOGS-CDG. MOGS is expressed in the endoplasmic reticulum and is involved in the trimming of N-glycans. We evaluated two siblings with CDG-IIb who presented with multiple neurologic complications and a paradoxical immunologic phenotype characterized by severe hypogammaglobulinemia but limited clinical evidence of an infectious diathesis. A shortened immunoglobulin half-life was determined to be the mechanism underlying the hypogammaglobulinemia. Impaired viral replication and cellular entry may explain a decreased susceptibility to infections.

Ibrutinib and other targeted inhibitors of B-cell receptor signaling achieve impressive clinical results for patients with chronic lymphocytic leukemia (CLL). A treatment-induced rise in absolute lymphocyte count (ALC) has emerged as a class effect of kinase inhibitors in CLL and warrants further investigation. We here report correlative studies in 64 patients with CLL treated with ibrutinib. We quantified tumor burden in blood, lymph nodes, spleen, and bone marrow, assessed phenotypic changes of circulating cells, and measured whole blood viscosity. With just one dose of ibrutinib the average increase in ALC was 66%, and in over 40% of patients the ALC peaked within 24 hours of initiating treatment. Circulating CLL cells on day 2 showed increased Ki67 and CD38 expression, indicating an efflux of tumor cells from the tissue compartments into the blood. The kinetics and degree of the treatment-induced lymphocytosis was highly variable; interestingly in patients with a high baseline ALC the relative increase was mild and resolution rapid. After two cycles of treatment the disease burden in lymph node, bone marrow, and spleen decreased irrespective of the relative change in ALC. Whole blood viscosity was dependent on both ALC and hemoglobin. No adverse events were attributed to the lymphocytosis.

About a quarter of patients with severe aplastic anemia remain pancytopenic despite immunosuppressive therapy. We have previously demonstrated that eltrombopag has efficacy in this setting with 44% (11/25) of patients having clinically significant hematologic responses. We now report safety and efficacy data on a further 18 patients and long-term follow-up on the entire cohort of 43 patients. The overall response rate was 17 of 43 patients (40%) at 3 to 4 months, including tri- and bilineage responses. The majority of patients who remained on eltrombopag in an extension study (14/17) continued to show improvement, and 7 eventually had significant increases in neutrophil, red cell, and platelet lineages. Five patients with robust near-normalization of blood counts had drug discontinued at a median of 28.5 months after entry (range, 9-37 months), and all maintained stable counts a median of 13 months (range, 1-15 months) off eltrombopag. Eight patients, including 6 nonresponders and 2 responders, developed new cytogenetic abnormalities on eltrombopag, including 5 with chromosome 7 loss or partial deletion. None evolved to acute myeloid leukemia to date. Eltrombopag is efficacious in a subset of patients with aplastic anemia refractory to immunosuppressive therapy, with frequent multilineage responses and maintenance of normalized hematopoiesis off treatment. This study is registered at www.clinicaltrials.gov as #NCT00922883.

BackgroundWe observed a syndrome of intermittent fevers, early-onset lacunar strokes and other neurovascular manifestations, livedoid rash, hepatosplenomegaly, and systemic vasculopathy in three unrelated patients. We suspected a genetic cause because the disorder presented in early childhood. MethodsWe performed whole-exome sequencing in the initial three patients and their unaffected parents and candidate-gene sequencing in three patients with a similar phenotype, as well as two young siblings with polyarteritis nodosa and one patient with small-vessel vasculitis. Enzyme assays, immunoblotting, immunohistochemical testing, flow cytometry, and cytokine profiling were performed on samples from the patients. To study protein function, we used morpholino-mediated knockdowns in zebrafish and short hairpin RNA knockdowns in U937 cells cultured with human dermal endothelial cells. ResultsAll nine patients carried recessively inherited mutations in CECR1 (cat eye syndrome chromosome region, candidate 1), encoding adenosine deaminase 2 (ADA2), that were predicted to be deleterious; these mutations were rare or absent in healthy controls. Six patients were compound heterozygous for eight CECR1 mutations, whereas the three patients with polyarteritis nodosa or small-vessel vasculitis were homozygous for the p.Gly47Arg mutation. Patients had a marked reduction in the levels of ADA2 and ADA2-specific enzyme activity in the blood. Skin, liver, and brain biopsies revealed vasculopathic changes characterized by compromised endothelial integrity, endothelial cellular activation, and inflammation. Knockdown of a zebrafish ADA2 homologue caused intracranial hemorrhages and neutropenia phenotypes that were prevented by coinjection with nonmutated (but not with mutated) human CECR1. Monocytes from patients induced damage in cocultured endothelial-cell layers. ConclusionsLoss-of-function mutations in CECR1 were associated with a spectrum of vascular and inflammatory phenotypes, ranging from early-onset recurrent stroke to systemic vasculopathy or vasculitis. (Funded by the National Institutes of Health Intramural Research Programs and others.) Adenosine deaminase 2 (ADA2) is an enzyme involved in purine metabolism and a growth factor that influences the development of endothelial cells and leukocytes. This study shows that defects in ADA2 cause recurrent fevers, vascular pathologic features, and mild immunodeficiency. Patients with autoinflammatory disease sometimes present with clinical findings that encompass multiple organ systems.(1) Three unrelated children presented to the National Institutes of Health (NIH) Clinical Center with intermittent fevers, recurrent lacunar strokes, elevated levels of acute-phase reactants, livedoid rash, hepatosplenomegaly, and hypogammaglobulinemia. Collectively, these findings do not easily fit with any of the known inherited autoinflammatory diseases. Hereditary or acquired vascular disorders can have protean manifestations yet be caused by mutations in a single gene. Diseases such as the Aicardi-Goutieres syndrome,(2),(3) polypoidal choroidal vasculopathy,(4) sickle cell anemia,(5) livedoid vasculopathy,(6) and the small-vessel vasculitides(7),(8) are examples of systemic ...

Haploinsufficiency of the hematopoietic transcription factor GATA2 underlies monocytopenia and mycobacterial infections; dendritic cell, monocyte, B, and natural killer (NK) lymphoid deficiency; familial myelodysplastic syndromes (MDS)/acute myeloid leukemia (AML); and Emberger syndrome (primary lymphedema with MDS). A comprehensive examination of the clinical features of GATA2 deficiency is currently lacking. We reviewed the medical records of 57 patients with GATA2 deficiency evaluated at the National Institutes of Health from January 1, 1992, to March 1, 2013, and categorized mutations as missense, null, or regulatory to identify genotype-phenotype associations. We identified a broad spectrum of disease: hematologic (MDS 84%, AML 14%, chronic myelomonocytic leukemia 8%), infectious (severe viral 70%, disseminated mycobacterial 53%, and invasive fungal infections 16%), pulmonary (diffusion 79% and ventilatory defects 63%, pulmonary alveolar proteinosis 18%, pulmonary arterial hypertension 9%), dermatologic (warts 53%, panniculitis 30%), neoplastic (human papillomavirus+ tumors 35%, Epstein-Barr virus+ tumors 4%), vascular/lymphatic (venous thrombosis 25%, lymphedema 11%), sensorineural hearing loss 76%, miscarriage 33%, and hypothyroidism 14%. Viral infections and lymphedema were more common in individuals with null mutations (P = .038 and P = .006, respectively). Monocytopenia, B, NK, and CD4 lymphocytopenia correlated with the presence of disease (P < .001). GATA2 deficiency unites susceptibility to MDS/AML, immunodeficiency, pulmonary disease, and vascular/lymphatic dysfunction. Early genetic diagnosis is critical to direct clinical management, preventive care, and family screening.

Constitutional GATA2 deficiency caused by heterozygous germline GATA2 mutations has a broad spectrum of clinical phenotypes including systemic infections, lymphedema, cytopenias, myelodysplasia, and a high risk of developing myeloid leukemias. GATA2 deficiency is recognized as a major MDS predisposition syndrome, germline GATA2 mutations are found in 7% of primary MDS cases in children and adolescents. Monosomy 7 and trisomy 8 are frequent chromosomal abnormalities in GATA2 deficiency and features of disease prognosis and malignant transformation. GATA2 mutations mostly affect two zinc finger domains and broadly classify into three major categories: missense, null, and regulatory region mutations. Profound monocytopenia, B-cell and NK-cell lymphopenias, and dendritic cell deficiency are specific for GATA2 deficiency. Absence of multi-lymphoid progenitor and decreased granulocyte -macrophage progenitors occur early in disease. There are limited studies of gene expression profiles in GATA2 deficiency and these usually in bulk populations, partly due to the paucity of cells in patients. How GATA2 deficiency negatively affects hematopoiesis, especially the preferential loss of specific lineages, is poorly understood. We performed single-cell RNA sequencing of sorted bone marrow CD34+ hematopoietic stem and progenitor cells (HSPCs) from eight GATA2 deficiency patients, who had various well characterized pathogenic GATA2 mutations and clinically manifest myelodysplasia (Fig A). We characterized transcriptomes in lineages, computationally defined cells with chromosomal abnormalities, and described gene expression of these cells. We first used gene expression signatures of single HSPCs from healthy donors to impute identity of stem cells or progenitors of erythroid/megakaryocytic (MEP), myeloid and lymphoid lineages, and then proceeded to reconstruct hematopoietic differentiation by pseudotemporal ordering. Mapping patients' cells onto normal hematopoiesis, we observed marked deficiency in granulocyte/monocyte/lymphocyte differentiation and relatively preserved MEP (Fig B, top). Based on signature genes of each differentiated lineage, we computed a score of gene expression to corresponding lineage in individual patient and found a significantly lower score for granulocyte/monocyte and B cell progenitors in patients, MEP scores tended to be higher in patients without significance (Fig B, bottom). Upregulated genes in patients' HSPCs related to erythroid differentiation, and cell cycle and proliferation (Fig C), while downregulated gene sets were highly enriched in immune responses (Fig D). Differential co-expressed genes were defined by weighted correlation network analysis; they were enriched in immune response and DNA repair (genes exhibited higher correlation in MTOR and T cell receptor signaling pathway in patients [Fig E]). We observed differential effects of GATA2 mutations in distinct lineages, which could only be resolved with the single cell method in rare cell populations. In HSCs, upregulated genes were related to apoptosis and downregulated genes were involved in maintenance of quiescence and cell cycle; there was increased expression of erythroid/megakaryocytic priming programs and decreased expression of lymphoid priming programs. We also observed lower GATA2 expression levels at initial stages of hematopoiesis, likely contributing to disturbed stem cell homeostasis in GATA2 deficiency. DNA repair genes were downregulated in trisomy 8 cells, possibly rendering these cells vulnerable to second-hit somatic mutations and additional chromosomal abnormalities. Cells with complex cytogenetics had defects in multi-lineage differentiation and cell cycle. In conclusion, germline GATA2 mutations modulate gene expression and change gene coexpression patterns. Distinct lineages show different transcriptional profiles resulting from GATA2 mutations. The prominent deficiency in myeloid/lymphoid lineages in GATA2 deficiency is partly due to expression of aberrant gene programs in HSCs prior to lineage commitment. Disclosures No relevant conflicts of interest to declare.

Background Hairy cell leukemia (HCL) variant (HCLv) is considered a separate, more aggressive entity compared to classic HCL. HCLv responds poorly to single-agent purine analog with complete response (CR) rates below 10% and overall response rates under 50%. Rituximab combined with purine-analog can improve response rate and duration, but long-term data have not been reported for HCLv, particularly regarding minimal residual disease (MRD). We therefore update the results of a phase II trial with cladribine and concurrent rituximab in patients with HCLv, previously reported for 10 of the 20 patients enrolled. Methods Patients with HCLv with 0 to 1 prior courses of cladribine, and/or 0-1 prior courses of rituximab, received cladribine (0.15 mg/kg days 1-5), with 8 weekly doses of rituximab (375 mg/m2) beginning day 1. The primary endpoint was to determine CR rate and secondary endpoints included evaluating minimal residual disease (MRD) by blood and bone marrow aspirate flow cytometry, and bone marrow biopsy immunohistochemistry. Patients were able to receive a 2nd course of rituximab ≥ 6 months after the first, if and when MRD was detected in blood. Results Twenty patients were enrolled. Median age was 67 (range: 42-86) years. No patients had prior concurrent cladribine-rituximab. Eight were previously untreated, 1 had only splenectomy, 6 had prior cladribine, 1 had prior cladribine and splenectomy, 1 had prior rituximab, 1 had prior rituximab and splenectomy, 1 had cladribine, rituximab, and splenectomy, and 1 had combination rituximab-containing chemotherapy followed by cladribine. Out of 20 patients receiving concurrent cladribine-rituximab (CDAR), the CR rate was 95% (95% CI: 75-100%). This CR rate was superior to a historical control group of 3 of 39 HCLv patients who achieved CR to cladribine alone (p Conclusion Concurrent cladribine with rituximab is highly effective in HCLv irrespective of prior purine-analog treatment or IGHV4-34 status and should replace purine analog monotherapy as treatment. Patients with long-term MRD-free CR are being followed to determine whether concurrent cladribine-rituximab as 1st-3rd line systemic therapy can permanently eradicate HCLv. Patients who progress have limited OS. This provides a rationale for the testing of higher intensity approaches up front and the identification of additional treatment options for HCLv. Disclosures Kreitman: Genentech: Research Funding. OffLabel Disclosure: Rituximab for hairy cell leukemia

Coding and regulatory human GATA2 mutations that deregulate protein expression and/or function cause immunodeficiency that often progresses to MDS/AML (McReynolds et al., 2018). In the mouse, decreased GATA2 expression impairs hematopoietic stem/progenitor cell (HSPC) genesis and function (de Pater et al., 2013; Gao et al., 2013; Tsai et al., 1994). While prior studies demonstrated Gata2 +9.5 and -77 enhancers are essential for HSC emergence (+9.5) and/or progenitor cell fate (+9.5 and -77) (Johnson et al., 2012; Johnson et al., 2015; Mehta et al., 2017) and hematopoietic regeneration (+9.5) (Soukup et al., 2019), the mechanisms mediating these processes are not completely established. The -77 enhancer is required for fetal liver progenitors to undergo erythroid, megakaryocytic, granulocytic and monocytic differentiation. By contrast, progenitors with a -77 homozygous deletion (-77-/-) exhibit a predominant monocytic cell fate and generate macrophages ex vivo (Johnson et al., 2015). Using multiomic and single-cell strategies, we asked how this enhancer orchestrates a balance between fate-promoting and -suppressing circuitry in cell populations and single cells. Quantitative proteomics was conducted to discover the -77-regulated protein ensemble conferring multiple fates in a myeloid progenitor population [Common Myeloid Progenitor (CMP) and Granulocyte-Monocyte Progenitor (GMP)] from E14.5 fetal liver of -77+/+ and -77-/- mouse embryos. -77-/- progenitors exhibited decreased levels of GATA2 (4.7-fold) and proteins generated from GATA2 target genes (GATA1: 51-fold; HDC: 52-fold). The 202 proteins upregulated in -77-/- progenitors highlighted immune and inflammatory mechanisms, while the 232 downregulated proteins were linked to erythroid, megakaryocyte and granulocyte biology, indicative of loss of these fate potentials. Innate immune machinery was upregulated in -77-/- vs. -77+/+ progenitors, including interferon (IFN) signaling pathway components such as the IFN-inducible transcription factor and critical monocytic differentiation determinant Interferon Regulatory Factor 8 (IRF8; 2.7 fold higher) (Kurotaki et al., 2013) and diverse pathogen sensors. Expressing GATA2 at physiological levels in -77-/- progenitors normalized the aberrant transcriptome. Since -77 deletion downregulated Gata2 and upregulated Irf8, we tested whether this opposing expression pattern occurs in distinct and/or identical cells in the population using single cell transcriptomics. -77 deletion decreased Gata2 expression, which was anti-correlative with Irf8, and detailed single cell analyses indicated that -77 loss downregulates GATA2, corrupting the transcriptome/proteome, Irf8 expression increases, and IRF8 enables or drives the predominant monocytic differentiation. To determine how GATA2-dependent mechanisms governing progenitor fate relate to those guiding HSPC expansion and differentiation during regeneration, we utilized our +9.5 human disease Ets motif mutation that abrogates myeloablation-dependent GATA2 induction and hematopoietic regeneration in bone marrow (Soukup et al., 2019). While population RNA-seq with Lin-Sca1+c-Kit+ (LSK) cells revealed little to no perturbations in the steady-state, 5-FU treatment of mutants led to altered expression of only 14% of the transcripts regulated in regenerating wild type cells (423/2974). Gene Ontology analysis of differentially expressed genes indicated that genes dysregulated by the Ets motif mutation included those linked to cell cycle regulation and cellular proliferation. As LSKs consist of LT-HSCs, ST-HSCs, and MPPs, we used single-cell transcriptomics to elucidate defective regenerative circuits in individual cells. Analysis of 17000-20000 wild type and mutant LSK cells revealed GATA2-dependent mechanisms distinct from those mediating progenitor cell fate control in the fetal liver. These studies have revealed context-dependent GATA2 mechanisms governing developmental and regenerative hematopoiesis, which will enable the development of strategies to detect, diagnose, and treat GATA2-linked blood diseases. Disclosures No relevant conflicts of interest to declare.

[Figure][1] A 72-year-old man presents with leukocytosis (30 × 109/L-40 × 109/L) with lymphocytosis (80%), monocytopenia, and anemia for 10 years. Peripheral smear revealed cells with cytoplasmic projections and atypical lymphocytes (panel A [Giemsa stain; original magnification ×1000]).

Bone marrow angiogenesis in myeloma and its precursor disease: a prospective clinical trial

The risk of progression to multiple myeloma (MM) from the precursor condition smoldering MM (SMM) varies considerably among individual patients. Reliable markers for progression to MM are vital to advance the understanding of myeloma precursor disease and for the development of intervention trials designed to delay/prevent MM. The Mayo Clinic and Spanish PETHEMA have proposed models to stratify patient risk based on clinical parameters. The aim of our study was to define the degree of concordance between these two models by comparing the distribution of patients with SMM classified as low, medium and high risk for progression. A total of 77 patients with SMM were enrolled in our prospective natural history study. Per study protocol, each patient was assigned risk scores based on both the Mayo and the Spanish models. The Mayo Clinic model identified 38, 35 and four patients as low, medium and high risk, respectively. The Spanish PETHEMA model classified 17, 22 and 38 patients as low, medium and high risk, respectively. There was significant discordance in overall patient risk classification (28.6% concordance) and in classifying patients as low versus high (p < 0.0001), low versus non-low (p = 0.0007) and high versus non-high (p < 0.0001) risk. There is a need for prospectively validated models to characterize individual patient risk of transformation to MM.

BACKGROUND: There has been increasing interest in serial research biopsies in studies of targeted therapies. Definition of patient characteristics and optimal target tissue for safe research tumor biopsy in the era of antiangiogenic and targeted agents is needed. METHODS: This institutional review board-approved, retrospective study included chart and interventional radiology case review from 6 phase 1/2 studies at the National Cancer Institute. RESULTS: One hundred forty-two of 150 protocol patients who were approached gave consent for research biopsies. Patients' median age was 56 years (range, 27-78 years), their median body mass index was 25.8 kg/m2 (range, 14.4-46.2 kg/m2), they had an Eastern Cooperative Oncology Group performance status of 0 or 1, and they had normal end-organ function. Baseline biopsies were collected from 138 of 142 patients (97%), and paired specimens were collected from 96 (70%). Most patients had metastatic gynecologic cancers (85%), and 78% had target disease below the diaphragm with a median size of 2.7 cm (range, 1-14.5 cm). Protocol therapies included kinase inhibitors (35%), angiogenesis inhibitors (54%), and olaparib/carboplatin (11%); therapy was not interrupted for biopsies. All adverse events were uncomplicated and were observed in 4 patients (liver subcapsular hematoma in 1 patient, vasovagal syncope in 2 patients, and pneumothorax in 1 patient). The complication rate in obese patients was similar to that in nonobese patients (3 of 108 patients vs 1 of 34 patients, respectively). Sixty-seven patients (48%) were receiving bevacizumab at the time of subsequent biopsies. The complication rate was not different between patients who were and were not receiving bevacizumab (3 of 67 patients vs 1 of 71 patients, respectively). Ninety-five percent of biopsies yielded useable material. CONCLUSIONS: Serial percutaneous core-needle biopsies can be obtained safely and yield material applicable for multiple translational applications. Obesity and/or concomitant antiangiogenic therapy and depth of disease did not increase the risk or preclude the successful acquisition of useful tissue. Cancer 2013. © 2012 American Cancer Society.

The proteasome inhibitor carfilzomib is highly effective in the treatment of multiple myeloma. It irreversibly binds the chymotrypsin-like active site in the β5 subunit of the 20S proteasome. Despite impressive response rates when carfilzomib is used in combination with immunomodulatory agents in newly diagnosed multiple myeloma patients; no biomarker exists to accurately predict response and clinical outcomes. We prospectively assessed the activity in peripheral blood of the chymotrypsin-like (CHYM), caspase-like (CASP) and trypsin-like (TRYP) proteolytic sites in 45 newly diagnosed multiple myeloma patients treated with eight cycles of carfilzomib, lenalidomide and dexamethasone (CRd) (NCT01402284). Samples were collected per protocol and proteasome activity measured through a fluorogenic assay. Median CHYM levels after one dose of carfilzomib decreased by >70%. CHYM and CASP activity decreased throughout treatment reaching a minimum after eight cycles of treatment. Higher levels of proteasome activity associated with higher disease burden (r>0.30; p

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is a rare primary immunodeficiency disorder typically caused by homozygous AIRE mutations. It classically presents with chronic mucocutaneous candidiasis and autoimmunity that primarily targets endocrine tissues; hypoparathyroidism and adrenal insufficiency are most common. Developing any two of these classic triad manifestations establishes the diagnosis. Although widely recognized in Europe, where nonendocrine autoimmune manifestations are uncommon, APECED is less defined in patients from the Western Hemisphere. We enrolled 35 consecutive American APECED patients (33 from the US) in a prospective observational natural history study and systematically examined their genetic, clinical, autoantibody, and immunological characteristics. Most patients were compound heterozygous; the most common AIRE mutation was c.967_979del13. All but one patient had anti–IFN-ω autoantibodies, including 4 of 5 patients without biallelic AIRE mutations. Urticarial eruption, hepatitis, gastritis, intestinal dysfunction, pneumonitis, and Sjögren’s-like syndrome, uncommon entities in European APECED cohorts, affected 40%–80% of American cases. Development of a classic diagnostic dyad was delayed at mean 7.38 years. Eighty percent of patients developed a median of 3 non-triad manifestations before a diagnostic dyad. Only 20% of patients had their first two manifestations among the classic triad. Urticarial eruption, intestinal dysfunction, and enamel hypoplasia were prominent among early manifestations. Patients exhibited expanded peripheral CD4+ T cells and CD21loCD38lo B lymphocytes. In summary, American APECED patients develop a diverse syndrome, with dramatic enrichment in organ-specific nonendocrine manifestations starting early in life, compared with European patients. Incorporation of these new manifestations into American diagnostic criteria would accelerate diagnosis by approximately 4 years and potentially prevent life-threatening endocrine complications.

Heterozygous GATA2 mutation is associated with immunodeficiency, lymphedema, and myelodysplastic syndrome. Disease presentation is variable, often coinciding with loss of circulating dendritic cells, monocytes, B cells, and natural killer (NK) cells. Nonetheless, in a proportion of patients carrying GATA2 mutation, NK cells persist. We found that peripheral blood NK cells in symptomatic patients uniformly lacked expression of the transcription factor promyelocytic leukemia zinc finger (PLZF), as well as expression of intracellular signaling proteins FceRγ, spleen tyrosine kinase (SYK), and EWS/FLI1-Activated Transcript 2 (EAT-2) in a variegated manner. Moreover, consistent with an adaptive identity, NK cells from patients with GATA2 mutation displayed altered expression of cytotoxic granule constituents and produced interferon-γ upon Fc-receptor engagement but not following combined interleukin-12 (IL-12) and IL-18 stimulation. Canonical, PLZF-expressing NK cells were retained in asymptomatic carriers of GATA2 mutation. Developmentally, GATA-binding protein-2 (GATA-2) was expressed in hematopoietic stem cells, but not in NK-cell progenitors, CD3-CD56bright, canonical, or adaptive CD3-CD56dim NK cells. Peripheral blood NK cells from individuals with GATA2 mutation proliferated normally in vitro, whereas lineage-negative progenitors displayed impaired NK-cell differentiation. In summary, adaptive NK cells can persist in patients with GATA2 mutation, even after NK-cell progenitors expire. Moreover, our data suggest that adaptive NK cells are more long-lived than canonical, immunoregulatory NK cells.

The lymph node (LN) is the site of chronic lymphocytic leukemia (CLL) cell activation and proliferation. Aberrant microRNA (miRNA) expression has been shown to have a role in CLL pathogenesis; however, a comparison of miRNA expression between CLL cells in the LN and the peripheral blood (PB) has previously not been reported. On the basis of the analysis of 17 paired LN and PB samples from CLL patients, we identify a panel of miRNAs that are increased in LN CLL cells correlating with an activation phenotype. When evaluated in CLL cells from 38 patients pre and post treatment with ibrutinib, a subset of these miRNAs (miR-22, miR-34a, miR-146b and miR-181b) was significantly decreased in response to ibrutinib. A concomitant increase in putative miRNA target transcripts (ARID1B, ARID2, ATM, CYLD, FOXP1, HDAC1, IBTK, PTEN and SMAD4) was also observed. Functional studies confirmed targets of ibrutinib-responsive miRNAs to include messenger RNA transcripts of multiple tumor suppressors. Knockdown of endogenous miR-34a and miR146b resulted in increased transcription of tumor suppressors and inhibition of cell proliferation. These findings demonstrate that ibrutinib downregulates the expression of a subset of miRNAs related to B-cell activation leading to increased expression of miRNA targets including tumor suppressors and a reduction in cell proliferation.

Common variable immunodeficiency (CVID) is characterized by late-onset hypogammaglobulinemia in the absence of predisposing factors. The genetic cause is unknown in the majority of cases, and less than 10% of patients have a family history of the disease. Most patients have normal numbers of B cells but lack plasma cells.We used whole-exome sequencing and array-based comparative genomic hybridization to evaluate a subset of patients with CVID and low B-cell numbers. Mutant proteins were analyzed for DNA binding with the use of an electrophoretic mobility-shift assay (EMSA) and confocal microscopy. Flow cytometry was used to analyze peripheral-blood lymphocytes and bone marrow aspirates.Six different heterozygous mutations in IKZF1, the gene encoding the transcription factor IKAROS, were identified in 29 persons from six families. In two families, the mutation was a de novo event in the proband. All the mutations, four amino acid substitutions, an intragenic deletion, and a 4.7-Mb multigene deletion involved the DNA-binding domain of IKAROS. The proteins bearing missense mutations failed to bind target DNA sequences on EMSA and confocal microscopy; however, they did not inhibit the binding of wild-type IKAROS. Studies in family members showed progressive loss of B cells and serum immunoglobulins. Bone marrow aspirates in two patients had markedly decreased early B-cell precursors, but plasma cells were present. Acute lymphoblastic leukemia developed in 2 of the 29 patients.Heterozygous mutations in the transcription factor IKAROS caused an autosomal dominant form of CVID that is associated with a striking decrease in B-cell numbers. (Funded by the National Institutes of Health and others.).

Background The ability to distinguish increased platelet (PLT) destruction from PLT hypoproduction is important in the care of patients with marrow failure syndromes and patients receiving high-dose chemotherapy. The measurement of immature circulating PLTs based on RNA content using an automated counter is now feasible. This study evaluated the impact of recent PLT transfusion on measurement of immature PLT variables. Study Design and Methods The immature PLT fraction (IPF) and absolute immature PLT number (AIPN) were measured using a hematology analyzer before and after PLT transfusion in nine transfusion-dependent patients with marrow failure secondary to aplastic anemia, myelodysplasia, or transplantation conditioning. IPF and AIPN were also measured serially over 5 days of storage in three plateletpheresis components collected from normal donors. Results PLT transfusion did not significantly change the mean AIPN in transfused patients. In contrast, IPF decreased significantly from 6.6 ± 4.6% on Day −1 to 2.3 ± 1.4% on Day 0 before returning to 4.3 ± 2.3% on Day +1. In the PLT component, AIPN and IPF% increased significantly over 5 days of storage, most likely due to an artifact of the staining and detection process for stored PLTs, no longer detected in vivo once the PLTs were transfused. Conclusion PLT transfusion decreases the IPF due to the resultant increase in circulating PLT count. However, PLT transfusion does not change the circulating AIPN, validating this assay as a reflection of ongoing PLT production by the marrow in various clinical settings, regardless of proximity to PLT transfusion.

Haploinsufficiency for GATA2 causes human immunodeficiency syndromes characterized by mycobacterial infection, myelodysplasia, lymphedema, or aplastic anemia that progress to myeloid leukemia. GATA2 encodes a master regulator of hematopoiesis that is also linked to endothelial biology. Though the disease-causing mutations commonly occur in the GATA-2 DNA binding domain, we identified a patient with mycobacterial infection and myelodysplasia who had an uncharacterized heterozygous deletion in a GATA2 cis-element consisting of an E-box and a GATA motif. Targeted deletion of the equivalent murine element to yield homozygous mutant mice revealed embryonic lethality later than occurred with global Gata2 knockout, hematopoietic stem/progenitor cell depletion, and impaired vascular integrity. Heterozygous mutant mice were viable, but embryos exhibited deficits in definitive, but not primitive, hematopoietic stem/progenitor activity and reduced expression of Gata2 and its target genes. Mechanistic analysis revealed disruption of the endothelial cell transcriptome and loss of vascular integrity. Thus, the composite element disrupted in a human immunodeficiency is essential for establishment of the murine hematopoietic stem/progenitor cell compartment in the fetal liver and for essential vascular processes.

A 25-year-old female with a history of Ewing sarcoma presented with leukopenia (920/μL), neutropenia (180/μL), thrombocytopenia (147,000/μL) and macrocytic anemia (hemoglobin 12.2 g/dL, mean corpuscular volume (MCV) 90.3 fL). Metastatic Ewing sarcoma of the right gluteal muscle with pulmonary metastases had been diagnosed 7 years previously. Prior treatment had included chemotherapy, radiation therapy, and allogeneic hematopoietic stem cell transplantation (alloHSCT).

microRNAs are increasingly recognized as significant players in oncogenesis and tumor biology through post-transcriptional gene regulation impacting broad pathways of proliferation, differentiation, apoptosis, metastasis and cell survival. Recent studies have found abnormal expression of microRNAs in multiple myeloma (MM). Currently, the precise role of these microRNAs in the biology of MM remains to be elucidated, although they are predicted to be involved in plasma cell proliferation, survival, homing, or in MM cell interactions with the bone marrow microenvironment. Furthermore, a limited number of studies focusing on MM precursor disease (monoclonal gammopathy of undetermined significance; MGUS) reveal significant differences in microRNA profiles between MGUS and normal plasma cells. Interestingly, several of the microRNAs differentially expressed in MGUS also show aberrant expression in MM suggesting a role in early myelomagenesis. MicroRNA profiles can discriminate molecular subtypes of MM that are defined based on gene expression profiling and cytogenetic abnormalities, demonstrating the potential diagnostic/prognostic utility of microRNA profiling for subclassification of MM. Given the relative stability of microRNA and ability to isolate microRNA from routine clinical specimens, microRNA analysis promises to facilitate personalized diagnostics and therapies, and to provide insights into the biology of early myelomagenesis.

Natural killer (NK) cells are involved in immune surveillance of various malignancies, including multiple myeloma (MM).[1][1] IPH2101 is a fully human monoclonal antibody that blocks HLA-C binding KIR2D receptors (KIR2DL/DS-1, -2 -3) expressed on the surface of NK-cells, enhancing their cytotoxicity

Eltrombopag (EPAG), a thrombopoietin receptor agonist, has been shown to improve hematopoiesis in patients with aplastic anemia (AA), but in MDS patients the effect of thrombopoietin mimetics in bone marrow function is still unclear. In this phase-2 dose escalation study, we investigated the safety and effectiveness of EPAG treatment in low to intermediate-2 risk MDS patients (NCT 00961064). Thirty patients were enrolled from March 2011 to July 2017. Preceding enrollment the majority of patients were either diagnosed with AA (n=13) or hypoplastic MDS (n=5). EPAG was started at 50 mg/day, up to a maximal dose of 150 mg/day, increasing the dose by 25mg every 2 weeks. The primary endpoint was hematologic response at 16 or 20 weeks, defined as either: (1) an increase in platelet counts ≥20.000/uL or transfusion independence for a minimum of 8 weeks; (2) hemoglobin (Hb) increase of ≥1.5g/dL from baseline, or a reduction in red blood cells (RBC) transfusion of at least 50%; or (3) an increase in absolute neutrophil counts (ANC) of ≥0.5x109/L or by at least 100% in patients with a baseline ANC The primary endpoint of hematological response was met in 14/30 patients (47%). All responders continued EPAG on the extension arm. In 3 patients, peripheral blood cell counts declined on EPAG after the initial response. One patient withdrew from the study. Ten of the 14 responding patients achieved a robust response (RR) after a median treatment duration of 15 months (range 7-27 months). Robust response was defined as stable hematopoiesis with at least a hemoglobin >10g/dl, and thrombocytes >50.000/L, and ANC>1000/L. However, peripheral blood cell counts significantly declined in 5/10 RR and EPAG was restarted per protocol. In 4 of these patients peripheral blood cell counts recovered. One patient did not achieve a second response. Based on International Prognostic Score System (IPSS), 4/30 (13%) patients progressed on study, including 3 non-responders and 1 responder, at a median follow-up of 4 months (3-35 months). The responding patient was diagnosed with increased bone marrow myeloblast 7 months after discontinuation of EPAG for robust response and 35 months after enrolling in the study. New cytogenetic abnormalities determined progression in non-responding patients (Figure). Novel dose limiting toxicities were not observed. Three patients developed CTCAE grade III hepatic toxicities. One of them discontinued EPAG at 3 months. Elevated transaminases returned to baseline after EPAG discontinuation in 2 patients. In both cases EPAG was resumed either at the same (150mg/day) or reduced dose (50mg/day) level. There were no treatment-related death cases. One patient died on study before the primary endpoint from acute respiratory distress syndrome. Sequential acquisition of genomic aberrations has been associated with malignant transformation. Targeting next-generation sequencing for somatic variants in genes previously associated with myeloid malignancies (Myeloid cancer genes, MCG) was performed in 29/30 patients with sufficient material (bone marrow mononuclear cells) available from baseline, primary endpoint, and at time of progression. At baseline, 22/29 (76%) patients were found with at least one mutation:TET2 (14.5%), ASXL1 (12.5%), SF3B1 (8.3%), SETBP1 (8.3%), ATM (8.3%), and ZRSR2 (8.3%). After EPAG, additional somatic variants in different genes were detected in 4/14 responders and 7/16 non-responders. Variants present at baseline were no longer detected in post EPAG samples from 4 responding and 6 non-responding patients. The VAF of variants detected at both time points were similar, indicating no selective expansion of clones with EPAG in neither responder, non-responder nor patients with progression based on IPSS. In conclusion, our results suggest that EPAG is well-tolerated and effective in restoring hematopoiesis in patients with low to intermediate-2 risk MDS, particular with a prior history of hypoplastic bone marrow failure syndromes. EPAG was discontinued for robust response in the majority of responders but declining blood cell counts were observed in about 50% of them. Variants in MCG were more common at study entry compared to patients with aplastic anemia (Yoshizato, NEJM, 2015). However, EPAG appears not to selectively promote expansion of clones harboring MCGs in this patient population. Disclosures Townsley: National Institute of Health: Research Funding. Scheinberg:Pfizer: Speakers Bureau; Novartis: Consultancy, Speakers Bureau; Janssen: Honoraria, Research Funding. Dunbar:National Institute of Health: Research Funding. Young:GlaxoSmithKline: Research Funding; CRADA with Novartis: Research Funding; National Institute of Health: Research Funding. Winkler:National Institute of Health: Research Funding.

Sporadic or familial germline mutations in GATA2 frequently result in a bone marrow failure syndrome characterized by recurrent life-threatening infections, cytopenias, and progression to myelodysplastic syndrome (MDS), acute myelogenous leukemia (AML), or chronic myelomonocytic leukemia (CMML). Hematopoietic stem cell transplantation (HSCT) represents the only definitive therapy for GATA2 deficiency. However, the highly variable disease penetrance in different families, and in mutation positive individuals within a single family, make the timing of HSCT challenging. We assessed the utility of scoring patient characteristics according to the Revised International Prognostic Scoring System (IPSS-R) to predict survival after HSCT in a cohort of 51 patients with GATA2 deficiency who had progressed to MDS. Higher IPSS-R scores significantly correlated with reduced overall survival after transplant. In evaluating the components of the IPSS-R score for patients with GATA2 deficiency, cytopenias, including anemia, neutropenia, and thrombocytopenia, were important variables in placing these patients in higher risk IPSS-R categories. Since GATA2 deficiency patients have very low peripheral blood monocyte, B cell, and NK cell counts, we evaluated these cytopenias in conjunction with IPSS-R scoring. These cytopenias also had prognostic value for outcome after HSCT in patients with GATA2 deficiency. Cytogenetics, another component of the IPSS-R score, also placed patients with GATA2 deficiency into higher risk categories. In particular, patients harboring monosomy 7 had poorer survival outcomes than patients with normal cytogenetics or trisomy 8. Of note, all five patients with GATA2 deficiency and trisomy 1q successfully underwent HSCT. Clonal cytogenetic progression with the development of additional cytogenetic aberrations was a harbinger of myeloid progression and led to HSCT. In a cohort of four patients who underwent HSCT following progression to AML/CMML, there was only one survivor. Thus, HSCT is recommended in patients with GATA2 deficiency and intermediate or high-risk IPSS-R scores before the development of AML or CMML. Disclosures No relevant conflicts of interest to declare.

Background Monoclonal gammopathy of undetermined significance (MGUS) is an asymptomatic condition arising from clonal plasma cells and has the risk of transformation to multiple myeloma (MM). Dysregulated expression of microRNAs (miRs) has been well demonstrated in MM, but miRs are not as well characterized in MGUS. We previously found an increased risk for MGUS in Vietnam veterans exposed to Agent Orange and its contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Here we report the effect of age on serum levels of 13 miRs in MGUS cases and controls from that study cohort. Methods The study base population comprised 958 US veterans who participated in the 2002 follow-up of the Air Force Health Study (AFHS). A total of 49 MGUS cases were identified by using their serum stored at the AFHS 2002 follow-up (Landgren O et al. JAMA Oncology, 2015). The current study included 47 MGUS cases and 85 controls. The controls were selected from the veterans who did not have MGUS, did not have a history of tumors, and whose TCDD level was below the third quartile value among the study base. Quantitative real-time PCR (qPCR) was used to determine the serum levels of 13 miRs (let-7a, let-7i, miR-16, miR-20a, miR-21, miR-34a, miR-106b, miR-146a, miR-181a, miR-192, miR-205, miR-335 and miR-361) that were previously shown to be dysregulated in MM or other cancers . The cycle threshold (Ct) values obtained from qPCR were normalized by using spiked-in cel-miR-39 as a control. Univariate rank regression was used to examine the relationships between relative expression of each miR and age, and each miR and MGUS status (MGUS vs control); each miR-MGUS relation was also examined with adjustment for age. All miR values were analyzed in log2 units. Continuously distributed age was summarized by the median and interquartile range (IQR): age variation with MGUS status was assessed with Kruskal-Wallis test. All statistical testing was two-sided with a significance level of p Results Overall MGUS cases were older than controls (median, controls 66 years [IQR 61, 69] versus MGUS 67 years [IQR 64, 71], p=0.03). Rank regression analysis showed that age was significantly and negatively correlated with the serum levels of 9 (let-7a, let-7i, miR-146a, miR-361, miR-106b, miR-16, miR-20a, miR-21, and miR-335) of the 13 miRs examined in controls. Among MGUS cases, age was significantly negatively correlated with only 5 (let-7a, miR-146a, miR-106b, miR-16, and miR-20a) of the 13 miRs and positively correlated with miR-181a and miR-205 (Table 1). In the univariate analysis of the miR-MGUS relationship, the serum levels of 4 miRs (let-7a, miR-106b, miR-16, and miR-21) were significantly associated with MGUS. However, none of these miRs remained significant after adjusting for age. In both adjusted and unadjusted analyses, the miR levels were lower in MGUS cases than in controls with the exceptions of miR-205 (unadjusted) and miR-335 (adjusted). Conclusions and Discussions In this study population, serum levels of the majority of miRs tested were negatively correlated with age in controls. Most of the same miRs were similarly decreased in MGUS with age, with the exception of miR-181a and miR-205 which were positively correlated with age. miR-181a is an important regulator of apoptosis, that is altered in many cancers, and was previously shown to be elevated in plasma cells of MM and MGUS. miR-205 inhibits tumor suppressors PTEN and SMAD4, and has been shown to be increased in several cancers. Of note, based on univariate analysis, several miRs were significantly differentially expressed in MGUS, but failed to remain significant after adjusting for age effect. This finding underscores the importance of assessing the need for age adjustment when analyzing serum miR data. We are currently exploring this data set to determine whether TCDD levels had any independent effect on miR levels in this population. Note: The first two authors contributed equally. Disclosures Landgren: Pfizer: Consultancy; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Consultancy, Research Funding; Amgen: Consultancy, Research Funding; Karyopharm: Consultancy; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Merck: Membership on an entity's Board of Directors or advisory committees.

Eltrombopag (EPAG) received FDA approval for treatment of refractory severe aplastic anemia (rSAA) in 2014, based on our phase I/II dose escalation trial of single agent EPAG for patients failing one or more treatment cycles with ATG/cyclosporine (Olnes NEJM 2012; Desmond Blood 2014). There is no standard treatment for patients with moderate aplastic anemia (MAA) or hypo-productive uni-lineage cytopenias (MAA/UC), conditions that can also impact on morbidity, mortality and quality of life. To explore the safety and effectiveness of EPAG in MAA/UC, we conducted a phase II study of EPAG given at escalating doses from 50-300mg/day (25-150mg/day for East Asians) through a primary hematologic response endpoint at 16-20 weeks (NCT 01328587). 34 patients enrolled between February 2012 and March 2017. 27 had never been treated with ATG/CSA IST. Responding patients could continue EPAG treatment on an extension arm. The drug was well-tolerated in 33/34 patients, with 1 patient coming off study at 10 weeks for nausea and vomiting. 25 patients reached the maximal dose. The median duration of follow-up in all patients was 16 months, and 27 months in responding patients. 17 of 34 (50%) of patients met criteria for response at the primary endpoint in at least one initially protocol-qualifying lineage (Hb 1.5 gr/dL increase in Hb or > 50% reduction in transfusions), including a patient with RSP19-mutated Diamond-Blackfan anemia. 7/24 with severe thrombocytopenia had a platelet response (>20,000/ul or transfusion-independence). 2/13 with both severe anemia and thrombocytopenia had bi-lineage responses at the primary endpoint, and an additional 5 went on to bi-lineage responses during the extension period. 3 patients without a response to EPAG were later treated with ATG/CSA and responded. EPAG was discontinued in 11/17 (65%) responding patients upon achievement of robust blood counts (Hb > 10mg/dL, platelets > 50,000/uL, and ANC > 1000) or stable blood counts for 6 months in 1 patient (6%) after a median duration of drug administration of 8 months (2-14 months) (Fig 1). In contrast to our prior experience in rSAA, the majority of patients still being followed on study after drug discontinuation (8/10) needed to have EPAG re-initiated for declining counts at a median of 6 months (2-38) later. All 8 responded again, with 4/8 able to discontinue EPAG after a second robust or stable response. 2/34 patients (6%) developed marrow cytogenetic abnormalities while on drug in contrast to 16/83 (16%) rSAA patients treated with EPAG in our prior studies. Both MAA patients were responders and neither had dysplastic changes or increased blasts. Patient # 5 had +8 in 7/20 metaphases at 22m, went off drug and relapsed, and EPAG was restarted off protocol. Repeat cytogenetics on EPAG were normal. Patient #20 had del13q in 5/20 metaphases at 9.5m, EPAG was stopped, and repeat cytogenetics off drug were normal. Of note, patient #12 had a robust response and had been off drug for 25m when counts declined and BM revealed dysplastic changes with no increase in blasts and normal cytogenetics. The acquisition and selection of somatic mutations, particularly in myeloid candidate genes (MCG) recurrently mutated in MDS/AMLhas been proposed to be an initiating step in clonal evolution. We performed targeted next generation exome sequencing (NGS) of 66 MCG and additional genes previously found to be somatically-mutated in SAA (Yoshizato, NEJM, 2015) pre-EPAG treatment and at the primary response endpoint of 16-20 weeks. Only 5 patients showed somatic mutations in these genes at baseline (SETBP1, CBL, SF3B1, PPMID, EP300). There were no significant changes in VAF. 2 mutations became detectable on EPAG (BCOR, and DNMT3A transiently), and 1 disappeared (SF3B1). In summary, administration of EPAG at escalating doses up to of 300mg/day was well-tolerated and 50% of patients with MAA/UC had clinically-meaningful responses, including those not previously treated with IST. The responses were durable, often robust, although frequently required ongoing EPAG treatment, in contrast to the experience in rSAA. Clonal cytogenetic evolution was rare, with no instances of chromosome 7 abnormalities, and there was no consistent expansion of MCG somatically-mutated clone size in patients during EPAG treatment. Figure. Figure. Disclosures Winkler: National Institute of Health: Research Funding. Young:CRADA with Novartis: Research Funding; GlaxoSmithKline: Research Funding; National Institute of Health: Research Funding. Dunbar:National Institute of Health: Research Funding.

Background: State of the art treatment for patients with NDMM involves induction with triplet-based regimens utilizing combinations of immunomodulatory drugs and proteasome inhibitors (PI) which improve time to progression (TTP), progression-free survival, and overall survival (OS) over doublet regimens. Carfilzomib is a selective PI with FDA approval in the KRd combination regimen for the treatment of patients with relapsed or refractory MM. Carfilzomib-based combinations are associated with increased clinical benefit over bortezomib-based combinations and carfilzomib does not cause neuropathy. This phase 2 study of 45 patients demonstrated that deep responses with KRd-r is achieved in the NDMM setting (Korde et al. JAMA Onc 2015). Here, we expand on our initial results in assessing response to present the long-term durability of minimal residual disease negativity (MRDneg) complete response (CR) and time to progression. We also characterize TTP by depth of response, age, and cytogenetic risk profile. Methods:Treatment-naïve patients with MM were treated for 8 cycles (28-day cycles) with carfilzomib 20/36 mg/m2 IV days 1, 2, 8, 9, 15, 16; lenalidomide 25 mg PO days 1-21, and dexamethasone 20/10 mg IV/PO days 1, 2, 8, 9, 15, 16, 22, 23. Transplant eligible patients underwent stem cell collection after ≥4 cycles and then continued KRd treatment (i.e. without default autologous stem cell transplant (ASCT)). After 8 cycles of KRd, patients received 2 years of lenalidomide 10 mg PO maintenance on days 1-21. The primary objective of the study was to estimate the rate of ≥ Grade 3 peripheral neuropathy with secondary objectives of International Myeloma Working Group criteria for overall response rate (ORR), MRDneg CR, TTP, and response duration (DoR) assessed after every cycle during induction and subsequently after every 90 days of maintenance therapy. Assessment of MRDneg CR by multi-color flow cytometry (bone marrow aspirate; 10-5 sensitivity) was performed after 8 cycles of induction, 1 and 2 years of lenalidomide maintenance, and then annually. Results: Forty-five patients meeting eligibility criteria were enrolled (60% male; 42% ≥ age 65, range 40-89; race: 82% White, 13% Black, 4% Asian; isotypes: 51% IgG kappa, 16% IgG lambda, 13% IgA kappa, 9% IgA lambda, 9% free kappa, and 4% free lambda; 33% high risk cytogenetics, del(17p), t(4;14), t(14;16)or t(14;20)). The median potential follow up was 5.7 years (68.3 months). The ORR was 97.8% (95% Confidence Interval (CI): 88.2-99.9%) with a median DoR of 65.7 months (95% CI: 55.6-not reached (NR) months). Strikingly, 28 of the 45 patients, 62.2%, (95% CI: 46.5-76.2%) attained deep responses of MRDneg CR; durability of MRDneg CR was observed up to at least 70 months with a median duration of over 4 years (52.4 months; 95% CI: 35.3-61.6 months). Moreover, the median TTP was over five and a half years (67.3 months; 95% CI: 51.0-NR months) and the median OS was NR, however, at 80 months, 84.3% of patients were still alive. As expected, patients who attained MRDneg CR, by cycle 8, had a 78% reduction in the risk of progression (Hazard Ratio (HR): 0.22 (95% CI: 0.07-0.69); p=0.005) (Figure 1). Importantly, these deep responses of MRDneg CR and long progression free durations were observed regardless of age group or cytogenetic-based risk profile (Table 1). Toxicities have been previously reported and were generally manageable with no Grade ≥ 3 neuropathy or death due to toxicity. Conclusions: Upfront treatment of NDMM with the modern and highly efficacious KRd-r regimen incorporating a "by-default-delayed" ASCT strategy led to high rates of MRDneg CR (10-5 sensitivity) which even more importantly were sustained with a median duration of over 4 years. Moreover, attaining MRDneg CR, was strongly associated with a delay in progression. Clinically important, we observed that these deep responses and long progression-free durations are observed regardless of age or cytogenetic risk and stress the importance of utilizing highly efficacious triplet-based regimens for these sub-categories of NDMM. Lastly, our results with KRd-r in NDMM compare favorably to ASCT-based regimens and question the use of upfront ASCT for all patients. Our observed median TTP of 67 months is approximately 17 months longer than published data using the regimen of bortezomib, lenalidomide, and dexamethasone with ASCT (Attal et al. NEJM 2017). Updated results will be presented at the Annual Meeting. Disclosures Korde: Amgen: Research Funding. Mailankody:Janssen: Research Funding; Juno: Research Funding; Takeda: Research Funding; Physician Education Resource: Honoraria. Landgren:Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Consultancy, Research Funding; Amgen: Consultancy, Research Funding; Merck: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Consultancy; Pfizer: Consultancy; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding.

Purpose: To evaluate clinical activity and target modulation of vandetanib in women with recurrent ovarian cancer. Experimental Design: A phase II trial of orally administered vandetanib 300 mg daily was designed to include analyses of target inhibition through paired biopsies and dynamic imaging. Core 18-gauge needle biopsies and dynamic contrast-enhanced magnetic resonance imaging were obtained before initiation of therapy and 6 weeks into therapy. Biopsy samples were subjected to reverse-phase protein lysate array endpoint analysis. Cytokine concentrations were measured by enzyme-linked immunosorbent assay in serially collected plasma samples. Results: Twelve patients entered the study, and accrual was terminated in the first stage because of lack of response or disease stabilization beyond 6 months. Adverse events included rash, diarrhea, and prolonged QT interval corrected for heart rate, but not hypertension. Exploratory analyses showed that epidermal growth factor receptor (EGFR) phosphorylation was reduced in the eight paired biopsy sets obtained; vascular endothelial growth factor (VEGF) receptor-2 phosphorylation was not consistently affected nor were dynamic contrast-enhanced MRI permeability and flow parameters. Serial plasma VEGF concentrations were variable and did not significantly change in the 11 patients assessed. Conclusions: Vandetanib 300 mg daily monotherapy had no significant clinical benefit in this disease setting. Proteomic analysis of paired biopsies detected both phosphorylated-EGFR and phosphorylated-VEGF receptor-2 in ovarian tumor tissue, but only phosphorylated-EGFR was measurably inhibited by vandetanib. Clin Cancer Res; 16(2); 664–72