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B cell acute lymphoblastic leukemia (ALL) is characterized by the highly heterogeneity of pathogenic genetic background, and there are still approximately 30–40% of patients without clear molecular markers. To identify the dysregulated genes in B cell ALL, we screened 30 newly diagnosed B cell ALL patients and 10 donors by gene expression profiling chip. We found that ECM1 transcription level was abnormally elevated in newly diagnosed B cell ALL and further verified in another 267 cases compared with donors (median, 124.57% vs. 7.14%, P < 0.001). ROC analysis showed that the area under the curve of ECM1 transcription level at diagnosis was 0.89 (P < 0.001). Patients with BCR::ABL1 and IKZF1 deletion show highest transcription level (210.78%) compared with KMT2A rearrangement (39.48%) and TCF3::PBX1 rearrangement ones (30.02%) (all P < 0.05). Also, the transcription level of ECM1 was highly correlated with the clinical course, as 20 consecutive follow-up cases indicated. The 5-year OS of patients (non-KMT2A and non-TCF3::PBX1 rearrangement) with high ECM1 transcription level was significantly worse than the lower ones (18.7% vs. 72.9%, P < 0.001) and high ECM1 transcription level was an independent risk factor for OS (HR = 5.77 [1.75–19.06], P = 0.004). After considering transplantation, high ECM1 transcription level was not an independent risk factor, although OS was still poor (low vs. high, 71.1% vs. 56.8%, P = 0.038). Our findings suggested that ECM1 may be a potential molecular marker for diagnosis, minimal residual disease (MRD) monitoring, and prognosis prediction of B cell ALL. Trial registration Trial Registration Registered in the Beijing Municipal Health Bureau Registration N 2007–1007 and in the Chinese Clinical Trial Registry [ChiCTR-OCH-10000940 and ChiCTR-OPC-14005546]; . [ABSTRACT FROM AUTHOR]

Mutations in the CCAAT/enhancer binding protein (CEBPA) gene occur in approximately 10% of all acute myeloid leukaemia (AML) cases, where half of the mutations are biallelic CEBPA (bi CEBPA), which has now been acknowledged to be associated with a favourable prognosis.1-5 However, long-term follow-up of cytogenetically normal CEBPA-mutated AML showed that the 5-year and 10-year cumulative incidence of relapse (CIR) rates were 37%-40% and 45% respectively, in bi CEBPA AML patients.4,6 Therefore, the rapid identification of high-risk relapse patients and pre-emptively treating patients with more aggressive therapies may improve survival. Reply to 'heterogeneity within AML with CEBPA mutations; only CEBPA double mutations, but not single CEBPA mutations are associated with favorable prognosis'. Prognostic implications of the detection of measurable residual disease and mutations based on next-generation sequencing in acute myeloid leukaemia with biallelic mutations of CEBPA Patients with persistent positive MRD status after two consolidation cycles, and/or MRD-negative status lost at any time (molecular relapse), were redefined as high-risk patients and recommended for allo-HSCT as pre-emptive treatment. [Extracted from the article]

To evaluate the efficacy of interferon-α (IFN-α) as maintenance therapy in patients with favorable-risk acute myeloid leukemia (AML), this retrospective study enrolled 84 patients with favorable-risk AML: 42 patients who received IFN-α maintenance therapy and 42 patients who did not (control). The median follow-up time and duration of IFN-α treatment was 26 (6–54) months and 18 (2–24) months, respectively. The 4-year estimated relapse-free survival (RFS) after the last consolidation chemotherapy was 86.8% (95% confidence interval (CI), 75.8–97.8%) in the IFN-α group and 55.7% (95% CI, 37.2–74.3%) in the control group (p=.007). The 4-year estimated overall survival was 94.4% (95% CI, 86.8–102%) and 76.4% (95% CI, 61.9–90.9%) in IFN-α and control groups, respectively (p=.040). The Cox regression analysis showed that IFN-α treatment was the only independent factor affecting RFS (p=.004). Maintenance therapy with IFN-α may prevent relapse in favorable-risk AML after consolidation chemotherapy. [ABSTRACT FROM AUTHOR]

Ras-related dexamethasone-induced 1 (RASD1) is abnormally expressed in many solid cancers. However, its potential role in adults with B-cell acute lymphoblastic leukemia (B-ALL) is unclear. Therefore, we aim to clarify the abnormal expression of the tumor-associated biomarker, RASD1, as a potential target for diagnosis and prognosis in adult Philadelphia-negative B-ALL. The expression of RASD1 was detected with RT-qPCR in 92 adults with de novo Ph-negative B-ALL and 40 healthy controls. The correlation between RASD1 transcript levels and relapse was assessed. RASD1 transcript levels in patients with Ph-negative B-ALL (median 81.76%, range 0.22%-1824.52%) were significantly higher than those in healthy controls (7.59%, 0.46%-38.66%; P<0.0001). Patients with low RASD1 transcript levels had a lower 5-year relapse-free survival (RFS, 47.5% [32.9%, 62.1%] vs. 63.1% [49.0%, 77.2%]; P = 0.012) and a higher 5-year cumulative incidence of relapse (CIR, 52.0% [37.4%, 66.6%] vs. 36.2% [22.2%, 50.2%]; P = 0.013) especially in patients receiving chemotherapy only. Multivariate analysis showed that a low RASD1 transcript level was an independent risk factor for RFS (HR = 2.938 [1.427, 6.047], P = 0.003) and CIR (HR = 3.367 [1.668, 6.796], P = 0.001) in patients with Ph-negative B-ALL. RASD1 transcript levels were significantly higher in patients with Ph-negative B-ALL and a low RASD1 transcript level was independently correlated with increased relapse risk. [ABSTRACT FROM AUTHOR]

Background: Currently, the prognostic stratification and therapeutic evaluation systems for multiple myeloma (MM) lack specific molecular indicators. OC‐STAMP is a new gene and is also highly expressed in MM. Methods: A total of 160 MM patients have been investigated with both quantitative reverse transcription PCR (RT‐qPCR), flow cytometry (FCM) and cytogenetic FISH on the same mononuclear cells isolated from bone marrow specimens. Results: We found that OC‐STAMP mRNA levels were significantly higher in newly diagnosed cases of MM than in healthy donors (median, 0.52% vs. 0.02%, P <.001). Moreover, the changes in the OC‐STAMP mRNA levels paralleled the disease stages and minimal residual disease, as detected by FCM. Furthermore, we found that patients with high OC‐STAMP mRNA levels were more likely to develop ≥3 bone lesions, be diagnosed with Durie‐Salmon stages III, and have the P53 (17p13) deletion. In addition, advanced stage patients with high OC‐STAMP mRNA levels had a lower 4‐year progression‐free survival (5.6% vs. 22.9%, P =.0055) and a worse 4‐year overall survival (25.8% vs. 48.8%, P =.0137) compared to patients with low mRNA levels of this indicator. Conclusions: OC‐STAMP may be a promising molecular indicator to monitor treatment effects and participate in the prognostic stratification of MM. [ABSTRACT FROM AUTHOR]

Summary: About 25% of patients with newly diagnosed acute myeloid leukaemia (AML) have normal cytogenetics and no nucleophosmin 1 (NPM1) mutation or Fms‐like tyrosine kinase 3 internal tandem duplication (FLT3‐ITD). The prognosis and best therapy for these patients is controversial. We evaluated 158 newly diagnosed adults with this genotype who achieved histological complete remission within two cycles of induction therapy and were assigned to two post‐remission strategies with and without an allotransplant. Targeted regional sequencing at diagnosis was performed and data were used to estimate their prognosis, including relapse and survival. In multivariable analyses, having wild‐type or mono‐allelic mutated CCAAT/enhancer‐binding protein alpha (CEBPA) [hazard ratio (HR) 2·39, 95% confidence interval (CI) 1·08–5·30; P = 0·032), mutated NRAS (HR 2·67, 95% CI 1·36–5·25; P = 0·004), mutated colony‐stimulating factor 3 receptor (CSF3R) (HR 2·85, 95% CI 1·12–7·27; P = 0·028) and a positive measurable residual disease (MRD)‐test after the second consolidation cycle (HR 2·88, 95% CI 1·32–6·30; P = 0·008) were independently correlated with higher cumulative incidence of relapse (CIR). These variables were also significantly associated with worse survival (HR 3·02, 95% CI 1·17–7·78, P = 0·022; HR 3·62, 95% CI 1·51–8·68, P = 0·004; HR 3·14, 95% CI 1·06–9·31, P = 0·039; HR 4·03, 95% CI 1·64–9·89, P = 0·002; respectively). Patients with ≥1 of these adverse‐risk variables benefitted from a transplant, whereas the others did not. In conclusion, we identified variables associated with CIR and survival in patients with AML and normal cytogenetics without a NPM1 mutation or FLT3‐ITD. [ABSTRACT FROM AUTHOR]

Summary: Dehydropeptidase‐1 (DPEP1) is a zinc‐dependent metalloproteinase abnormally expressed in many cancers. However, its potential role in adults with B cell acute lymphoblastic leukaemia (ALL) is unknown. We found that in adults with common B cell ALL high DPEP1, transcript levels at diagnosis were independently associated with an increased cumulative incidence of relapse (CIR) and worse relapse‐free survival (RFS) compared with subjects with low transcript levels. We show an increased proliferation and prosurvival role of DPEP1 in B cell ALL cells via regulation of phosphCREB and p53, which may be the biological basis of the clinical correlation we report. Our data implicate DPEP1 expression in the biology of common B cell ALL in adults. We report clinical correlates and provide a potential biological basis for these correlations. If confirmed, analysing DPEP1 transcript levels at diagnosis could help predict therapy outcomes. Moreover, regulation of DPEP1 expression could be a therapy target in B cell ALL. [ABSTRACT FROM AUTHOR]

Many studies have confirmed that overexpressed WT1 exists in leukemic cells, especially in AML. However, the immunophenotypic features of this sort of leukemic cells remain to be unclarified. We retrospectively analyzed the immunophenotype of 283 newly diagnosed AML patients with intermediated and poor cytogenetic risk to evaluate the correlation between phenotype and WT1 overexpression. EVI1 transcripts, KMT2A-PTD, FLT3-ITD, and NPM1 mutations were simultaneously assessed. Our results revealed that overexpressed WT1 was significantly associated with the expression of CD117, CD13, and CD123. Besides, leukemic cells with WT1 overexpression also lacked lymphoid and myeloid differentiation-related markers. FAB subtype M2 patients had higher WT1 levels, compared with other FAB subtype. Multivariate analysis was proved that NPM1 mutation, M2 subtype, and the expression of CD123 were independently associated with WT1 overexpression. These indicated that AML with overexpressed WT1 was proliferated and blocked in the early stage of AML development. It presumably provided some clues to detect overexpressed WT1 cells via multiparameter flow cytometry. CD123-targeted drugs might become one of the alternative treatments for patients with WT1 overexpression. [ABSTRACT FROM AUTHOR]

For acute myeloid leukemia (AML) with nucleophosmin 1 mutation (NPM1m), multiparameter flow cytometry (FCM) and real-time quantitative polymerase chain reaction (RQ-PCR) are used to monitor minimal residual disease (MRD). However, the results of the two methods are sometimes inconsistent. This study was designed to analyze how to address the discordant results of FCM and RQ-PCR in AML patients undergoing chemotherapy, especially when positive FCM (FCM+) and negative NPM1m (NPM1m-) results are detected in the same sample. Our study included 93 AML patients with NPM1m positive (NPM1m+) who received chemotherapy but did not undergo hematopoietic stem cell transplantation. We monitored NPM1m and leukemia-associated immunophenotypes (LAIPs) by RQ-PCR and FCM, respectively, to assess MRD after each chemotherapy course. After each course of chemotherapy, all patients were classified into four groups based on the results of FCM and RQ-PCR: both negative (group 1, FCM-NPM1m-), single positive (group 2, FCM-NPM1m+; group 3, FCM+NPM1m-), or both positive (group 4, FCM+NPM1m+). The results showed that there was not a significant difference in the 2-year cumulative incidence of relapse (CIR) after each course of chemotherapy between group 2 and group 3. Furthermore, patients in groups 2 and 3 had a lower 2-year CIR than those in group 4 and a significantly higher 2-year CIR than those in group 1 after the first two courses. The patients in group 4 had a significantly higher 2-year CIR than those in group 1 after the first two courses. These results suggested that in the MRD monitoring process of AML patients, when the results of FCM and RQ-PCR are inconsistent (especially when FCM is positive and NPM1m is negative), these single-positive results still have predictive significance for relapse. [ABSTRACT FROM AUTHOR]

Acute myeloid leukemia (AML) patients with biallelic CEBPA (bi CEBPA) mutations are considered prognostically favorable, but 38–58% of them still relapse. Therefore, recognizing patients with a high risk of relapse is important. We retrospectively analyzed 83 bi CEBPA AML. Minimal residual disease (MRD) was detected by multiparameter flow cytometry (MFC). Patients with MRD positivity during consolidation chemotherapy had inferior 3-year CIR (55% vs. 36.7%; p =.037) and RFS (45% vs. 63.3%; p =.037) than those with MRD negativity. In patients with adverse cytogenetics, FLT3-ITD or MRD positivity, allogeneic hematopoietic stem cell transplantation (allo-HSCT) achieved superior 3-year CIR (0% vs. 52.8%; p =.006) and RFS (88.9% vs. 47.2%; p =.027) than did consolidation chemotherapy. Consolidation chemotherapy maintained a relatively favorable outcome (3-year CIR, 29%; 3-year RFS, 71%) in patients with intermediate cytogenetics, negative FLT3-ITD, and MRD negativity. Therefore, MFC-MRD could predict relapse and was complementary to genetics for risk stratification treatment in bi CEBPA AML. [ABSTRACT FROM AUTHOR]

A high frequency of MAGE‐CT (cancer testis) antigens are expressed in Multiple Myeloma (MM) patients; however, in other plasma cell dyscrasias, their potential function remains unclear. We measured the expression of MAGE‐CT genes (MAGE‐C1/CT7, MAGE‐A3, MAGE‐C2/CT10) in 105 newly diagnosed amyloid light‐chain (AL) amyloidosis patients between June 2013 and January 2018 at Peking University People's Hospital using real‐time quantitative polymerase chain reaction. In the newly diagnosed AL patients, the positive expression rates of patients with MAGE‐C1/CT7, MAGE‐C2/CT10 and MAGE‐A3 were 83.8% (88/105), 56.71% (38/67) and 22.0% (13/59) respectively. There was no significant correlation between organ propensity and MAGE‐CT gene expression. Changes in the MAGE‐C1/CT7 levels were consistent with a therapeutic effect. The expression levels of MAGE‐C1/CT7, MAGE‐C2/CT10 and MAGE‐A3 provide potentially effective clinical indicators for auxiliary diagnoses and monitoring treatment efficacy in AL amyloidosis patients. [ABSTRACT FROM AUTHOR]

Summary: Refinement of risk stratification in Philadelphia chromosome (Ph)‐negative B‐cell acute lymphoblastic leukaemia (ALL) might aid the identification of patients who are likely to relapse. Abnormal S100 calcium binding protein A16 (S100A16) has been implicated in various cancers, but its function remains unclear. We found S100A16 transcript levels were higher in 130 adults with newly‐diagnosed Ph‐negative B‐cell ALL compared with 33 healthy controls. In 115 of 130 patients who achieved first complete remission, those with high S100A16 transcript levels displayed a lower 3‐year cumulative incidence of relapse (CIR; 34% [21, 47%] vs. 40% [48, 72%]; P = 0·012) and higher 3‐year relapse‐free survival (RFS; 65% [53, 78%] vs. 35% [23, 46%]; P = 0·012), especially when receiving chemotherapy only. In multivariate analysis a low S100A16 transcript level was independently‐associated with a higher CIR (Hazard ratio [HR] = 3·74 [1·01–13·82]; P = 0·048) and inferior RFS (HR = 5·78 [1·91, 17·84]; P < 0·001). Function analysis indicated that knockdown of S100A16 promoted proliferation and anti‐apoptosis and reduced chemosensitivity. S100A16 over‐expression revealed an opposite trend, especially in a xeno‐transplant mouse model. Western blotting analysis showed upregulation of PI3K/AKT and ERK1/2 in S100A16‐knockdown and S100A16‐overexpression B‐cell ALL cell lines respectively. Inhibition assays suggested these two signalling pathways participated in the S100A16‐mediated proliferation and survival effects in B‐cell ALL cell lines. Trial Registration: Registered in the Chinese Clinical Trial Registry [ChiCTR‐OCH‐10000940]; http://www.chictr.org.cn. [ABSTRACT FROM AUTHOR]

Background: Daunorubicin is a traditional chemotherapeutic agent that plays a pivotal role in leukemia therapy. However, the dose-related toxicity remains a considerable challenge. The apoptosis-regulating gene, PDCD5, is downregulated in various tumors, including leukemias, and may provide a potential target for the diagnosis and treatment of leukemia. The purpose of this study was to construct a triple-regulated oncolytic adenovirus carrying a PDCD5 gene expression cassette (SG611-PDCD5) and explore the combined antitumor efficacy of SG611-PDCD5 in combination with low dose daunorubicin on leukemic cells. Materials and methods: A variety of leukemic cell lines, including K562, MEG-01, KG-1a, HL-60, SUP-B15, and BV-173, were cultured according to the providers' instructions. The insertion and orientation of all recombined plasmids were confirmed by restriction enzyme digestion and PCR. The tumor-selective replication of the constructed conditionally replicating SG611-PDCD5 and its antitumor efficacy in combination with daunorubicin were characterized in leukemic cell lines in vitro and in a nude mouse xenograft model. Cell viability was detected using cell-counting kit-8. Apoptosis was detected in whole living cells using flow cytometry and in paraffin-embedded tumor tissues using a terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Results: The triple-regulated CRAd carrying SG611-PDCD5 and nude mouse xenograft models of K562 cells were successfully constructed. In vitro treatment with SG611-PDCD5 in combination with low-dose daunorubicin elicited more potent anti-proliferative and proapoptotic effects in leukemic cells in a dose-dependent manner. The Chou-Talalay analysis revealed synergistic anti-proliferative effects in all of the above cell lines. In the nude mice xenograft model, the tumor size in the control, daunorubicin, SG611-PDCD5, and combined treatment groups on day 10 were 170.1±47.8, 111.9±81.1, 60.7±12.3, and 33.2±17.5 mm3, respectively (all P [ABSTRACT FROM AUTHOR]

V- set and transmembrane domain- containing 1 ( VSTM1), which is downregulated in bone marrow cells from leukemia patients, may provide a diagnostic and treatment target. Here, a triple-regulated oncolytic adenovirus was constructed to carry a VSTM1 gene expression cassette, SG611-VSTM1, and contained the E1a gene with a 24-nucleotide deletion within the CR2 region under control of the human telomerase reverse transcriptase promoter, E1b gene directed by the hypoxia response element, and VSTM1 gene controlled by the cytomegalovirus promoter. Real-time quantitative PCR and Western blot analyses showed that SG611-VSTM1 expressed VSTM1 highly efficiently in the human leukemic cell line K562 compared with SG611. In Cell Counting Kit-8 and flow cytometric assays, SG611-VSTM1 exhibited more potent anti-proliferative and pro-apoptotic effects in leukemic cells compared with SG611 and exerted synergistic cytotoxicity with low-dose daunorubicin (DNR) in vitro. In xenograft models, SG611-VSTM1 intratumorally injected at a dose of 1 × 10 plaque forming units combined with intraperitoneally injected low-dose DNR displayed significantly stronger antitumor effects than either treatment alone. Histopathologic examination revealed that SG611-VSTM1 induced apoptosis of leukemic cells. These results implicate an important role for VSTM1 in the pathogenesis of leukemia, and SG611-VSTM1 may be a promising agent for enhancing chemosensitivity in leukemia therapy. [ABSTRACT FROM AUTHOR]

Background Calreticulin (CALR) mutations were recently identified in a substantial proportion of persons with essential thrombocythemia (ET) and with primary myelofibrosis (PMF) without JAK2V617F. Consequently rapid, sensitive, and specific methods to detect and quantify these mutations are needed. Methods We studied samples from 1088 persons with myeloproliferative neoplasms (MPNs) including 421 JAK2V617F negative subjects with ET, PMF, polycythemia vera (PV), chronic myeloid leukemia (CML) and hyper-eosinophilic syndrome (HES). Detection of CALR exon 9 mutations was done by PCR amplification followed by fragment length analysis and direct sequencing. Dilution assays were used to determine CALR mutant allele burden. Results We detected CALR mutations in blood and bone marrow samples from 152 subjects with ET and with PMF but not in samples from normal or persons with PV, CML, or HES. CALR mutant peaks were distinct from wild-type peaks and dilution experiments indicated a sensitivity level of 0.5–5% for a CALR mutant allele in a wild-type background. Diverse types of mutations were detected including deletions, insertions, and complex indels. All mutations were confirmed by direct sequencing. We also used dilution experiments to quantify mutant allele burden. We were able to reproducibly detect mutant allele levels as low 5% (0.5–5%) in a wild-type background. Conclusions PCR amplification followed by fragment length analysis is a rapid, sensitive, and specific method for screening persons with MPNs for CALR mutations, especially those with ET and PMF and for estimating mutant allele burden. [ABSTRACT FROM AUTHOR]

The Abelson (ABL) gene was the best control gene for quantitative PCR (qPCR)-based diagnosis and minimal residual disease detection in leukemic patients. However, there is still no concerted effort focused on the optimization of control genes in multiple myeloma (MM). The results of this study will provide a basis for the use of ABL as a control gene for the quantification of aberrantly expressed genes in MM. We analyzed ABL, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), beta-glucuronidase, and β-microglobulin genes expression in bone marrow samples of 62 MM patients and 31 healthy donors. MAGE-C1, the most commonly expressed cancer-testis antigen gene in MM, which is to be a potential clinical indicator for auxiliary diagnosis and prognostic evaluation in MM, was also detected. Our experimental results show that the copy numbers of the four control genes were well correlated in all samples detected. The quantitative data for MAGE-C1 using the four control genes also had high correlations. ABL and GAPDH genes were stably expressed in healthy donors and MM patients during therapy and did not vary with disease state. ABL is stable in the MM bone marrow mononuclear fraction, and it could be used as a reliable control gene for the normalization of qPCR studies in MM. [ABSTRACT FROM AUTHOR]

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PDCD5 (programmed cell death 5) accelerates apoptosis of certain tumor cells and the replication-defective Ad-PDCD5 may be a promising agent for enhancing chemosensitivity. In this study, a triple-regulated conditionally replicating adenoviruses (CRAd) carrying PDCD5 gene expression cassette, SG611-PDCD5, was engineered. In SG611-PDCD5, the E1a gene with a deletion of 24 nucleotides within CR2 region is controlled under the human telomerase reverse transcriptase (hTERT) promoter, the E1b gene expression is directed by the hypoxia response element (HRE), whereas the PDCD5 gene is controlled by the cytomegalovirus promoter. The tumor-selective replication of this virus and its antitumor efficacy were characterized in several leukemic cell lines in vitro and in xenograft models of human leukemic cell line in nude mice. It was found by RQ-RT-PCR assay that SG611-PDCD5 expressed PDCD5 efficiently in leukemic cells. In K562 tumor xenograft models, SG611-PDCD5 displayed a tumor killing capacity. At a dose of 1 × 109 plaque-forming units, SG611-PDCD5 alone could completely inhibit the tumor growth and more effective than replication-defective Ad-PDCD5. Histopathologic examination revealed that SG611-PDCD5 administration resulted in leukemic cell apoptosis. We concluded that the triple-regulated SG611-PDCD5, as a more potent and safer antitumor therapeutic, could provide a new strategy for leukemia biotherapy. [ABSTRACT FROM AUTHOR]

Recently, mutations in the nucleophosmin ( NPM1) gene were detected in 50–60% of adult acute myelogenous leukemia (AML) patients, mainly with a normal karyotype. In this study, we detected typical NPM1 mutations (types A, B, D) in untreated Chinese AML patients using real-time quantitative polymerase chain reaction (RQ-PCR) followed by sequence analysis. The detection rate of NPM1 mutations in 220 AML patients was 16.4%, including 107 (14.2%) with the French–American–British (FAB) subtype M2, 43 (2.3%) with M3, and 52 (30.8%) with M4/M5. Only one case each with an NPM1 mutation was detected in four M0, seven M1, five M6, and two M7 cases. Eight patients were followed up after treatment, and five patients in hematologic remission continued to test negative for NPM1 mutations within 2–14 months of follow-up. Sequence analysis revealed that all the 36 positive cases were heterozygous for the mutation with 4-bp insertions at nt 959; the 36 cases included 29 (80.6%) cases with type A, four (11.1%) cases with type B, and one rare DD-3 mutation. We also detected two new mutations, namely, CTCG and CAAG insertions, named BJ-01 and BJ-02, respectively. Further, 38.9% (14/36) patients with NPM1 mutations simultaneously exhibited internal tandem duplications in the FLT3 gene, and 66.7% (22/33) patients did not express CD34. The results demonstrated that RQ-PCR was a reliable and sensitive method for detecting NPM1 mutations, for screening AML, and for the quantitative analysis of minimal residual diseases. [ABSTRACT FROM AUTHOR]

PDCD5 (programmed cell death 5) accelerates apoptosis of certain tumor cells and is expressed at low levels in marrow-nucleated cells of AML and CML patients. In the present study, we evaluated the effects of PDCD5 overexpression on drug sensitivity of leukemia cells. K562 cells were treated with idarubicin (IDR) alone or in combination with adenoviral vectors expressing PDCD5 (Ad-PDCD5). As shown by annexin-V-FITC/PI dual labeling, apoptosis rates were markedly increased after combined treatment with Ad-PDCD5 compared to IDR treatment alone. We observed that PDCD5 overexpression significantly improves the antitumor effects of low dose IDR treatment in vivo. Tumor sizes were significantly decreased in combined Ad-PDCD5 and low dose IDR treatment groups compared with single IDR treatment groups. Similar results were obtained with combined systemic treatment of Ad-PDCD5 and low dose IDR, and combined treatment with Ad-PDCD5 local injection and low dose IDR i.p. injection. These results indicate that Ad-PDCD5 may be a promising agent for enhancing chemosensitivity. [ABSTRACT FROM AUTHOR]

Apoptosis is reduced in the synovial tissue of patients with rheumatoid arthritis (RA), possibly due to decreased expression of pro-apoptotic genes. Programmed Cell Death 5 (PDCD5) has been recently identified as a protein that mediates apoptosis. Although PDCD5 is down-regulated in many human tumors, the role of PDCD5 in RA has not been investigated. Here we report that reduced levels of PDCD5 mRNA and protein are detected in RA synovial tissue (ST) and fibroblast-like synoviocytes (FLS) than in tissue and cells from patients with osteoarthritis (OA). We also report differences in the PDCD5 expression pattern in tissues from patients with these two types of arthritis. PDCD5 showed a scattered pattern in rheumatoid synovium compared with OA, in which the protein labeling was stronger in the synovial lining layer than in the sublining. We also observed increased expression and nuclear translocation of PDCD5 in RA patient-derived FLS undergoing apoptosis. Finally, overexpression of PDCD5 led to enhanced apoptosis and activation of caspase-3 in triptolide-treated FLS. We propose that PDCD5 may be involved in the pathogenesis of RA. These data also suggest that PDCD5 may serve as a therapeutic target to enhance sensitivity to antirheumatic drug-induced apoptosis in RA. [ABSTRACT FROM AUTHOR]