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How lysosome and MTORC1 signaling interact remains elusive in terminally differentiated cells. A G4C2 repeat expansion in C9orf72 is the most common cause of familial amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) (C9ALS-FTD). We previously identified a C9orf72-SMCR8-containing complex. Here we found that c9orf72 and smcr8 double-knockout (dKO) mice exhibit similar but more severe immune defects than the individual knockouts . In c9orf72 or smcr8 mutant macrophages, lysosomal degradation and exocytosis were impaired due to the disruption of autolysosome acidification. As a result of impaired lysosomal degradation, MTOR protein was aberrantly increased, resulting in MTORC1 signaling overactivation. Inhibition of hyperactive MTORC1 partially rescued macrophage dysfunction, splenomegaly and lymphadenopathy in c9orf72 or smcr8 mutant mice. Pharmacological inhibition of lysosomal degradation upregulated MTOR protein and MTORC1 signaling in differentiated wild-type macrophages, which resemble phenotypes in KO mice. In contrast, C9orf72 or Smcr8 depletion in proliferating macrophages decreased MTORC1 signaling. Our studies causatively link C9orf72-SMCR8's cellular functions in lysosomal degradation, exocytosis, and MTORC1 signaling with their organism-level immune regulation, suggesting cell state (proliferation vs. differentiation)-dependent regulation of MTOR signaling via lysosomes. Abbreviations : ALS: amyotrophic lateral sclerosis; ATG13: autophagy related 13; BMDMs: bone marrow-derived macrophages; BafA 1 : bafilomycin A 1 ; C9orf72: C9orf72, member of C9orf72-SMCR8 complex; CD68: CD68 antigen; ConA: concanamycin A; dKO: double knockout; DENN: differentially expressed in normal and neoplastic cells; FTD: frontotemporal dementia; GEF: guanine nucleotide exchange factor; IFNB1: interferon beta 1, fibroblast; IFNG: interferon gamma; IL1B/IL-1β: interleukin 1 beta; IL6: interleukin 6; iPSCs: induced pluripotent stem cells; LAMP1: lysosomal-associated membrane protein 1; LPOs: LAMP1-positive organelles; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; LPS: lipopolysaccharide; MTORC1: mechanistic target of rapamycin kinase complex 1; MEFs: mouse embryonic fibroblasts; MNs: motor neurons; NOS2/iNOS: nitric oxide synthase 2, inducible; RAN: repeat-associated non-AUG; RB1CC1/FIP200: RB1-inducible coiled-coil 1; RPS6/S6: ribosomal protein S6; RPS6KB1/S6K1: ribosomal protein S6 kinase, polypeptide 1; SMCR8: Smith-Magenis syndrome chromosome region, candidate 8; SQSTM1/p62: sequestosome 1; TFEB: transcription factor EB; TNF: tumor necrosis factor; TSC1: TSC complex subunit 1; ULK1: unc-51 like kinase 1; v-ATPase: vacuolar-type H⁺-translocating ATPase.

Objective: Anemia and thrombocytopenia are the most frequently reported adverse events of ruxolitinib in patients with MPN-associated myelofibrosis (MPN-MF). Although thalidomide, androgens and prednisone have previously demonstrated improvements in myelofibrosis-associated anemia, it is unclear whether these drugs are effective in patients taking ruxolitinib. Method: We conducted a retrospective cohort study to evaluate the efficacy and tolerability of combination therapy with low dose thalidomide, stanozolol and prednisone (TSP) in patients with IPSS intermediate-2 or high-risk myelofibrosis (MF) who received ruxolitinib treatment. Results: Sixty-five patients with MPN-MF who took ruxolitinib were enrolled in this retrospective study, of which 46 patients also took TSP while 19 did not take TSP (TSP and non-TSP groups). Within the first 24 weeks, the proportion of patients with anemia response and platelet count increase ≥50 × 10 9 /L were 45.7% and 67.4% in the TSP group as compared to 0% and 10.5% in the non-TSP group ( p  < 0.001). The mean hemoglobin level in the non-TSP group reached the nadir after approximately 12-16 weeks of therapy, but gradually increased in the TSP group. Conclusion: In summary, TSP regimen can improve anemia and thrombocytopenia during ruxolitinib treatment in patients with MPN-MF, and the associated adverse events were manageable.

Objective: Myelofibrosis (MF) is a pathologic entity of myeloproliferative neoplasm (MPN) characterized by bone marrow fibrosis, extramedullary hematopoiesis, splenomegaly, and constitutional symptoms that severely affect the quality of life accompanied with the risk of leukemia development. Conventional treatment is usually ineffective and has limited impact on prolongation of survival. Dysregulated Janus kinase (JAK) signaling is common in MPN. In two randomized controlled trials, ruxolitinib, a potent pan-JAK inhibitor, has been shown to be highly effective in patients with intermediate- and high-risk MF., Method: We retrospectively analyzed the therapeutic outcome of 10 MF patients treated with ruxolitinib in our institute. Basic clinical data, JAK2V617F mutational status and Myelofibrosis Symptoms Assessment Form (MF-SAF) to evaluate disease-related symptoms were recorded initially, and at every visit., Result: Among these patients, only half of the patients harbored JAK2V617F mutation. After treatment with ruxolitinib, all patients had reduction of splenic size and reached nadir by week 24. Nine patients had body weight increment, and four of them had body weight increment more than 10%. Seven patients had their total symptom score reduced by more than 50% after therapy. The efficacy of ruxolitinib was irrelevant to JAK2V617F mutational status. Adverse events were mainly hematological and easily manageable., Discussion and Conclusion: Ruxolitinib is both safe and efficacious in a cohort of Asian patients with MF. The efficacy of ruxolitinib is irrelevant to the mutational status of JAK2V617F.

Objectives: Mature lymphoid neoplasms presenting with 'prominent splenomegaly without significant lymphadenopathy' are uncommon and pose unique diagnostic challenges as compared to those associated with lymphadenopathy. Their descriptions in the literature are largely limited to a few case series. We analyzed the spectrum of these lymphomas diagnosed by peripheral blood (PB) and/or bone marrow (BM) examination., Methods: Over a period of 6 years, 75 patients were diagnosed with a lymphoma from PB/BM who had presented with predominant splenomegaly. Their clinical and laboratory records including PB and BM morphology; immunophenotyping using multi-parametric flow-cytometry and immunohistochemistry were reviewed. Wherever indicated, an extended panel of immunohistochemistry (IHC) was performed on BM biopsies for accurate sub-classification., Results and Discussion: The commonest lymphomas were hairy cell leukemia (HCL) (32%) and splenic marginal zone lymphoma (SMZL) (24%). Others included diffuse large B cell lymphoma (8%), chronic lymphocytic leukemia/small lymphocytic lymphoma (8%), mantle cell lymphoma (2.7%), and follicular lymphoma (1.3%), all of which usually presents with lymphadenopathy. SMZL was the commonest lymphoma among females and those with massive splenomegaly and lymphocytosis; while HCL was commonest in patients with pancytopenia. SMZL commonly presented with lymphocytosis; however, 22% of them also presented with pancytopenia., Conclusion: The high diagnostic efficacy of PB and BM examination using flow-cytometry and immunohistochemistry in confirming and sub-classifying splenic lymphomas suggests that a thorough hematological evaluation should always precede a diagnostic splenectomy. Immunohistochemistry remains the best modality to identify sparse or intra-sinusoidal infiltration on BM biopsy and is particularly useful in patients with fibrotic marrows and pancytopenia.

Objectives: Distinctive splenomegaly resulting from extramedullary hematopoiesis and infiltration of neoplastic cells is observed in some patients with myelofibrosis (MF) or malignant lymphoma. Palliative splenic irradiation is known to be effective for such patients and is widely performed. However, little is known about the biological mechanism of palliative splenic irradiation. Various reports have focused on irradiation doses, in terms of efficacy and safety. We examined the toxicity of myelosuppression and the timing of the platelet, white blood cell, and red blood cell count nadirs within 3 months after the start of irradiation in a total of eight patients with MF or malignant lymphoma, all of whom underwent palliative splenic irradiation at our hospital between 2004 and 2013., Methods: Five patients with idiopathic MF and three patients with non-Hodgkin's lymphoma (NHL) treated with splenic irradiation between 2004 and 2013. Of the three patients with NHL, two had diffuse large B-cell lymphoma and one had mantle cell lymphoma. There were four male and four female patients, with median age of 61 years (range, 51-73). Patients with MF received irradiation at 20-100 cGy per fraction dose; four patients received irradiation five times a week and one patient received irradiation three times a week. In three of these patients, the irradiation dose was gradually increased while observing for hematotoxicity. Patients with NHL received irradiation at a fraction dose of 150-200 cGy, and all received irradiation five times a week. Irradiation was terminated when we judged symptoms to be alleviated, splenomegaly reduced, or efficacy to be poor. With regard to the total irradiation dose, 175, 320, 400, 600, and 640 cGy were given to one MF patient each, and 1050 and 3000 cGy were given to one and two NHL patients, respectively., Results: Symptoms diminished or disappeared in five of the six symptomatic patients (83%). A reduction in the size of the spleen was confirmed in five of six patients (83%) with splenomegaly. For MF, the platelet count nadir was observed at week 3 in two patients, week 5 in two, and week 6 in one patient. For NHL, it was observed at week 1 in one patient, week 4 in one, and week 9 in one patient. For MF, the white blood cell count nadir was observed in at week 2 in one patient, week 3 in two, and week 5 in two patients. For NHL, it was observed at week 1 in one patient and week 4 in two patients. For MF, the red blood cell count nadir was observed at week 1 in two patients, week 3 in one, week 7 in one, and week 8 in one patient. For NHL patients, it was observed at week 1 in one patient, week 4 in one, and week 9 in one patient. Discussion There was a trend for the nadir to be steeper in patients with MF than in those with NHL. With regard to the total dose, symptoms diminished at the minimum dose of 175 cGy in MF patients, whereas the maximum dose of 3000 cGy was not effective in NHL patients. These observations suggest that a splenic lesion in NHL patients may be the primary site of neoplastic cell infiltration and that extramedullary hematopoiesis may not necessarily occur in the spleen., Conclusion: Although palliative irradiation of splenic lesions in patients with MF or NHL is safe and effective, optimal irradiation doses may differ for MF and NHL. More cases need to be accumulated to elucidate these differences.

We previously showed that widespread expression of Nras G12D/G12D from its endogenous locus in mice leads to an acute myeloproliferative disease (MPD) with a complete penetrance, whereas bone marrow-specific expression of Nras G12D/G12D in recipient mice did not result in sustained MPD phenotypes but 100% penetrant acute T-cell lymphoblastic leukemia/lymphoma (TALL). Such a phenotypic switch also is seen in the case of endogenous oncogenic Kras. Two possibilities might account for this observation and they are not necessarily mutually exclusive. First, the MPD phenotypes in primary Nras G12D/G12D mice might be a transient phenomenon attributable to microenvironmental factors that do not necessarily imply the potential for long-term maintenance in a hematopoietic-cell autonomous manner. Second, it is likely that MPD phenotypes are maintained by genetically altered hematopoietic stem cells (HSCs). Nras G12D/G12D signaling might substantially alter HSC behaviors (e.g. induce their proliferative exhaustion) so that these HSCs no longer sustain MPD phenotypes to a lethal stage in recipient mice. Here, we show some preliminary results to support the second hypothesis. Our results suggest that different lineages of hematopoietic cells might have differential requirements of HSC activity and Nras G12D signaling during leukemogenesis.

A 6-hour-old infant was admitted with severe respiratory distress and hepatosplenomegaly. Her mother had arthralgia for 4 weeks in the 7/8th month of pregnancy and the infant was born at 31 weeks. Brucella spp was detected in blood culture and serology in mother and infant, supporting the diagnosis of brucellosis with presumed transplacental transmission.

A 57-year-old woman with splenomegaly, moderate anemia and a paraspinal mass was found to have strikingly increased erythropoiesis, which was left shifted and dysplastic with many multinucleated cells. An increased percentage of CD34-positive and CD117-positive cells suggested a diagnosis of pure erythroleukemia. Further investigations were performed.

A 54-year-old man with chronic idiopathic myelofibrosis (CIMF) underwent RIST. His clinical course had been uneventful until day 60, when splenomegaly reappeared. Hepatic dysfunction developed on day 75. Recipient-type hematopoiesis increased to 51% on day 90. After rapid tapering of cyclosporin, serum levels of AST and ALP normalized in parallel with recovery of complete chimerism on day 134. Yet, jaundice progressed. He died of liver failure on day 176. Postmortem examination revealed neither GVHD nor VOD. Graft rejection following RIST for CIMF may lead to fatal hepatic damage through extramedullary hematopoiesis in the liver or cytokine-mediated immune dysregulations.

Glucose-6-phosphate dehydrogenase (G6PD) is an enzyme of the pentose phosphate shunt pathway a major function of which is to prevent cellular oxidative damage. Deficiency in red blood cells is associated with a number of varied clinical manifestations. Chronic non-spherocytic haemolytic anaemia is uncommon but is usually characterized by chronic haemolysis, often with severe anaemia. In the past splenectomy in this condition has been thought to be of questionable benefit. We report a case of G6PD Guadalajara where splenectomy produced transfusion independence and have reviewed the literature. Those cases with exon 10 mutations often have a severe clinical phenotype, which responds to splenectomy. This procedure should be considered in this condition.

Enhanced neutrophil apoptosis has been reported in neutropenic hepatosplenic schistosomiasis. The shortening of neutrophil survival via apoptosis may explain the neutropenia that occur in these patients. However, the regulation of neutrophil apoptosis in hepatosplenic schistosomiasis has not been clearly defined. Neutrophils harvested from neutropenic patients with hepatosplenic (HS) schistosomiasis, (n=25), non-neutropenic patients with hepatointestinal (HI) schistosomiasis (n=10), and age-/gender-matched healthy control subjects (n=10) were incubated with autologous serum. Neutrophils apoptosis was quantified by flow cytometry through determination of propidium iodide nuclear staining and confirmed by DNA gel electrophoresis at 0 (i.e. fresh neutrophils), 4 and 24 h culture. Neutrophils from healthy subjects were also incubated with either 10% heterologous normal or neutropenic serum, with and without anti-Fas ligand antibody. Fas expression was assessed in fresh neutrophils using flow cytometry. Compared with normal healthy neutrophils, and HI neutrophils, neutropenic neutrophils demonstrated greater apoptosis in the presence of autologous serum (P<0.01, 0.05, respectively). Furthermore, compared with normal neutrophils exposed to heterologous normal serum, those exposed to heterologous neutropenic serum exhibited higher apoptosis rates ( P<0.01). Moreover, anti-Fas L antibody attenuated the neutropenic serum-induced neutrophil apoptosis in normal neutrophils. Fas expression was significantly higher in the neutropenic group when compared to both HI and normal healthy controls (P<0.05). In addition, Fas expression by neutrophils was paralleled by high neutrophil apoptosis. On the other hand, neutrophil apoptosis was not correlated to the size of spleen in neutropenic group. In conclusion, the rate of neutrophil apoptosis is accelerated in patients with neutropenic hepatosplenic schistosomiasisis. These findings suggest that the enhanced neutrophil apoptosis that occurs in neutropenic HS patients is triggered by a serum factor, which is mostly a Fas ligand.

Incidence of apoptosis was investigated in the spleen and lymph nodes of +/+, CD18 -/- and urokinase receptor (uPAR, CD87) -/- mice, untreated or Plasmodium Berghei Anka (PbA) infected. In non infected mice, incidence of apoptosis was lower in the lymph nodes of CD18 -/- and uPAR -/- than in +/+ mice, as seen by FACS analysis to count the number of hypodiploid and Annexin-V binding cells. Infection of mice with PbA resulted in a marked increase in the size of spleen and lymph nodes 7-8 days after infection, which was slightly higher in uPAR -/- and CD 18 -/- than in +/+ mice. PbA infection increased about 7 fold the incidence of apoptosis in the lymphoid organs of +/+, especially in the white pulp and germinal centers of the spleen and lymph nodes, while in contrast it was unchanged in PbA infected CD 18 -/- or uPAR -/- mice. Serum IgG levels, and number of circulating leukocytes were significantly higher in both uPAR and CD18 -/- than in +/+ mice. These results indicate that the CD18 and uPAR surface molecules, which are known to be associated in the cell membrane, have an important influence upon the incidence of cell survival in both normal or stimulated lymphoid organs.

Intravascular lymphoma is a rare, often fatal disease characterized by a widespread intravascular proliferation of neoplastic lymphoid cells. Dermatological and bizarre neurological manifestations usually predominate. We report a case of intravascular lymphomatosis with an exceptional clinical presentation showing splenomegaly combined with early bone marrow involvement. The diagnosis was made on bone marrow biopsy examination using both immunohistochemistry and molecular biology analysis. We stress the histopathological features of bone marrow involvement by intravascular lymphoma which allow the prompt recognition of this disease. Early systemic chemotherapy, which represents the only chance of remission in such an aggressive disease, can then be initiated.

We describe 4 cases of adult T-cell leukemia (ATL) with unusual morphology and aberrant immunophenotype. All patients were Japanese and born in the Nagasaki district, an area endemic for HTLV-I. Peripheral blood and/or bone marrow films revealed bizarre giant cells with and without large nucleoli; the cells were 5 to 6 times the diameter of erythrocytes, resembling Hodgkin's cells. Some peripheral blood cells were morphologically similar to prototypic ATL cells, while many other cells in the bone marrow showed unusual morphology. Furthermore, leukemic cells had aberrant immunophenotypes such as the CD8-positive type in patients 1 and 2, the CD4-.CD8- double-negative type in patient 3, and the CD5 antigen defect in patient 4. All patients had marked elevations of the serum calcium and LDH and organomegaly, while all had a short survival. Anti-HTLV-I antibodies and provirus DNA monoclonality were demonstrated in all patients. The results suggested that the unusual morphology and aberrant ATL cell immunophenotype may be indicative of a high grade malignant behaviour of ATL.

A young man with an infectious mononucleosis underwent an emergency splenectomy for a spontaneous splenic rupture. This is a rather rare complication of mononucleosis caused on the one hand by a change in the histological structure of the spleen and on the other hand by a splenomegaly. The prognosis is favourable when the diagnosis is made on time and the correct treatment has been started immediately. With the exception of those cases which are haemodynamically stable (the lesion is limited and corresponds to a subcapsular haematoma), splenectomy remains the treatment of choice. Conservatively treated patients must be closely followed and at the first sign of destabilization, surgical intervention is required as soon as possible.

Fourteen cases of chronic lymphocytic leukaemia (CLL) and massive splenomegaly associated with anaemia and/or thrombocytopenia (stage C) with or without mechanical distress underwent splenectomy. Eleven regressed to stage A and 2 to stage B. All 6 patients with mechanical distress were relieved of their symptoms. Among 13 patients with anaemia, haemoglobin (Hb) level was normalised in 3, improved in 8 and showed no change in 2 cases. Among 13 patients with thrombocytopenia, platelet count was normalised in 10, improved in 1 and was unchanged in 2 cases. Mean Hb level increased from 89 g/l to 125 g/l and mean platelet count from 77 x 10(9)/l to 241 x 10(9)/l (p < 0.001 for both). Duration of response lasted for a mean period of 42.1 (CI 20.8-63.5) months. Mean survival after splenectomy was 44.5 months (CI 21.2-67.7). There was no operative mortality but 4 patients had significant post-operative morbidity. It is concluded that splenectomy is beneficial in advanced cases of CLL with massive splenomegaly and cytopenia.