Cytogenetic abnormalities in Tunisian de novo myelodysplastic syndrome: a comparison with other populations

Cytogenetic analysis was performed on 224 bone marrow (BM) of Tunisian patients with de novo myelodysplastic syndrome (MDS) at our institution from January 1993 to December 2006.According to French–American–British (FAB) criteria, there were 36% of patients with refractory anaemia (RA), 26% with refractory anaemia with excess of blasts (RAEB), 10% with refractory anaemia with ringed sideroblasts (RARS), 12% with chronic myelomonocytic leukaemia (CMML), 9% refractory anaemia with excess of blasts in transformation (RAEB-t) and 7% of unclassified MDS. A clonal chromosomal abnormality was observed in 51% of the patients. The most frequent karyotypic change was 5q− in 30 cases (13%), followed by −7/7q− in 17 cases (8%), del(12p) in 8 cases (4%), del(20q) and trisomy 8 in 7 cases each (3%), i(17q) in 2 cases (1%) and −y in only one case (0.4%).This is the first large comparative series of MDS from an Arab country, with cytogenetic analysis showing haematological and cytogenetic features similar to those of MDS population of European or mixed European-subsaharian African origin (like Brazil), but different from those seen in Eastern populations.     

A prospective, randomised, phase II study of horse antithymocyte globulin vs rabbit antithymocyte globulin as immune-modulating therapy in patients with low-risk myelodysplastic syndromes.

Immunosuppression has recently been proposed for low-risk myelodysplastic syndromes (MDS) to reverse bone marrow failure by inhibiting intramedullary secretion of proapoptotic cytokines. We treated 35 MDS patients (24 refractory anaemia (RA), 10 RA with excess blasts and one chronic myelomonocytic leukaemia) with either horse antithymocyte globulin 15 mg/kg/day or rabbit antithymocyte globulin 3.75 mg/kg/day, each for 5 days. Median age was 63 years (range: 41-75). After 1 to 34+ months of follow-up (mean: 15+), four patients experienced complete haematological responses (CR), six good responses (GR) and two minor responses. All CRs and GRs occurred in patients with RA, in whom both horse and rabbit ATG yielded five responses out of 12 (42%). Time to response varied between 1 and 10 (mean: 3) months. The median duration of response was 9+ (1-17+) months; five patients are in continuing response. In all, 23 patients suffered side effects > degrees II WHO (the degree of toxicity encountered according to the internationally accepted WHO toxicity grading); one patient died 2 weeks after rabbit ATG from rhinocerebral mucormycosis. Parameters that correlated with response were duration of disease and RA subgroup. In our experience, immune-modulating therapy with either horse or rabbit ATG is feasible in patients with RA and short duration of disease.     

Alpha-interferon in myelodysplasia; clinical observations and effects on NK cells

A total of 15 patients with myelodysplastic states (MDS) were studied. Of the eight patients treated with alpha-interferon (alpha IFN) (3 megaunits/day for up to 6 months), one patient with refractory anaemia with excess blasts (RAEB) underwent an almost complete response while one case of chronic myelomonocytic leukaemia (CMML) showed a reduction in monocyte count; no improvement was observed in refractory anaemia (RA) or refractory anaemia with excess blasts in transformation (trRAEB). In all patients Leu7+ and Leu11a+ phenotypic natural killer (NK) cells were consistently normal in percentage numbers but functional NK activity was consistently reduced in all MDS subgroups. NK activity was enhanced by exposure to alpha IFN in vitro, but was very variable in patients being treated with the agent. There was no correlation between clinical response and changed NK activity in patients receiving alpha IFN. It is concluded that NK cells are unlikely to play a central role in the biology of myelodysplasia.     

Heterogeneity of acquired idiopathic sideroblastic anaemia (AISA).

Clinical, haematological and outcome data were studied in 84 patients with acquired idiopathic sideroblastic anaemia (AISA) from a registry of 613 consecutive myelodysplastic syndromes (MDS) recorded by five institutions in western France. Two groups could be identified and compared: 'pure' erythroblastic AISA (AISA-E: 59 pts), and AISA with myelodysplastic features, i.e. dysgranulo and/or dysmegakaryopoiesis (AISA-M: 25 pts). Results were also compared to those of a series of 71 cases of refractory anaemia without sideroblastosis (RA) carried out from the same registry. Dyserythropoiesis was present in 90% of all AISA subtypes, dysgranulopoiesis in 88% of the AISA-M cases; dysmegakaryopoiesis was observed in 44% of AISA-M. Ten patients with both forms of AISA showed high platelet counts. These cases appeared particular in that four of them were associated with a splenomegaly and/or a hyperleucocytosis. They had to be distinguished from myeloproliferative syndromes. Outcome comparison of AISA-E with AISA-M showed a significant discrepancy of survival duration (60 vs 38 months respectively). Progression towards refractory anaemia with excess of blasts or acute leukaemia, was significantly higher for AISA-M than for AISA-E. The risk of transformation increased to 24% for the AISA-M group similarly to those of RA patients (17%). We conclude that AISA must be divided into two categories, 'pure' AISA and AISA-M, because survival duration and risk of transformation are different.     

Myelodysplastic syndromes in patients under 50 years old: a single institution experience

We report on our experience relating to 62 patients with myelodysplastic syndrome (MDS) aged less than 50 years, seen at our Institution and conservatively treated from July 1983 to December 2000. Patients demographics and clinical features at diagnosis were analysed for their prognostic value on survival and on risk of transformation to acute leukaemia. The median age at diagnosis was 43 years (range 21-50). According to FAB criteria there were 30 patients with refractory anaemia (RA), 3 with refractory anaemia with ringed sideroblasts (RARS), 18 with refractory anaemia with excess of blasts (RAEB), 6 with refractory anaemia with excess of blasts in transformation (RAEB-t) and 5 with chronic myelomonocytic leukaemia (CMML). Fifty patients had evaluable cytogenetic analysis: the most frequent karyotypic change was trisomy of chromosome 8 (10%), followed by monosomy 7 (6%); partial chromosome deletions and translocations were also common abnormalities, occurring on the whole in 16% of patients. At a median follow-up of 15 months 19 patients (31%) progressed to acute myeloid leukaemia (AML). From univariate analysis we identified some features, which appeared to be predictive of outcome and risk of transformation to AML. Age above 40 years (p = 0.002) and high risk according to IPSS score (p = 0.002) were found to be predictive for a shorter survival; FAB grouping (p = 0.0001), percentage > 5% of blasts in the bone marrow (p = 0.001) and high risk by IPSS score (p = 0.0003) were found to be predictive for a higher risk of transformation to AML. Presenting features in young MDS patients may identify subjects at higher risk of unfavourable outcome.     

Trisomy 21 as the sole acquired karyotypic abnormality in acute myeloid leukemia and myelodysplastic syndrome

We report five cases of myeloid disorders in which trisomy 21 (+21) was found as the sole acquired karyotypic abnormality, comprising two cases of acute myeloid leukemia (AML) and three cases of myelodysplastic syndrome (MDS). In this series, MDS patients with +21 presented as high grade disease, which included two cases of refractory anemia with excess of blasts (RAEB) and one case of refractory anemia with excess of blasts in transformation (RAEBt), and showed rapid disease progression. Significant thrombocytopenia was observed in all three patients, and bone marrow examination showed a marked reduction in megakaryocytes. AML patients with +21 included one case each of AML-M2 and M4. Despite the poor prognosis reported in AML patients with +21 as the sole abnormality, the patient in our series who was able to complete intensive treatment was cured of disease. The role of +21 in leukemogenesis is reviewed.     

CDKN2B methylation status and isolated chromosome 7 abnormalities predict responses to treatment with 5-azacytidine.

5-Azacytidine, a DNA methyl transferase inhibitor, is effective in patients with myelodysplastic syndromes (MDS). Whether responses to 5-Azacytidine are achieved by demethylation of key genes or by cytotoxicity is unclear. Of 34 patients with MDS or acute myeloid leukaemia (AML) treated with 5-Azacytidine, 7 achieved complete remissions (CR) (21%) and 6 achieved haematological improvement. All six had less than 5% bone marrow (BM) blasts at the time of haematological improvements (HI) (2 had pre-existing refractory anaemia (RA), 4 had refractory anaemia with excess blasts (RAEB)). A further patient with RAEB had blast reduction to less than 5% without HI. Five of the seven (71%) complete responders had chromosome 7 abnormalities. BM CR predicted longer overall survival (OS) (median 23 versus 9 months, P=0.015). Bisulphite genomic sequencing (BGS) of the CDKN2B (p15(INK4b)) promoter showed low level, heterogeneous pretreatment methylation (mean 12.2%) in 14/17 (82%) patients analysed. Lower baseline methylation occurred in responders (9.8% versus 16.2% in non-responders P=0.07). No response was seen in patients with >24% methylation, in whom p15(INK4b) mRNA was not expressed. 5-Azacytidine reduced CDKN2B methylation by mean 6.8% in 8/17 (47%) patients, but this did not correlate with response. At 75 mg/m(2), cell death (reduced BM cellularity (P=0.001) and increased apoptosis (P=0.02)) rather than demethylation of CDKN2B correlates with response. Patients with >24% methylation may benefit from alternative dosing or combination strategies.     

Abnormalities of chromosome 16q in myeloid malignancy: 14 new cases and a review of the literature.

Fourteen patients with abnormalities of chromosome 16q, 13 with acute myelogenous leukaemia (AML), and one with refractory anaemia with excess of blasts (RAEB), are described. Seven patients had inv(16)(p13q22), two had del(16)(q22), and five had other abnormalities of 16q. Six of the seven patients with inv(16) had AML M4Eo and, following treatment with adriamycin, cytosine arabinoside, and 6-thioguanine, all achieved complete remission (CR). Neither patient with del(16)(q22) had typical M4Eo morphology at diagnosis; CR was achieved in one and one had resistant leukaemia. Patients with other abnormalities of 16q had blasts of diverse morphology and, although morphologically abnormal eosinophils were seen in three patients, this was not as marked as in the patients with inv(16). CR was achieved in two of the four patients with other abnormalities of 16q but duration of remission was short in both cases. These results suggest that most patients with del(16)(q22) and other abnormalities of 16q22 do not have typical AML M4Eo. Such patients tend to have a worse prognosis, and are more likely to have complex karyotypes typical of secondary leukaemia.     

Up-regulation of DNA methyltransferases DNMT1, 3A, and 3B in myelodysplastic syndrome

Analyzing bone marrow trephines from (myelodysplastic syndrome) MDS patients we show for the first time strong over-expression of the DNA methyltransferases 1, and 3A (and 3B to a much lesser extent) in the myelodysplastic syndrome FAB subtypes refractory anaemia (RA) and refractory anaemia with excess of blasts (RAEB). The increase in mRNA expression was much less pronounced in refractory anaemia with ringed sideroblasts (RARS). Classification according to the new WHO guidelines revealed distinct differences between RCMD and RARS. This elevated mRNA expression most probably contributes to the frequently found aberrant hypermethylation in MDS and might explain the promising clinical response of MDS patients treated with DNMT inhibitors.     

Cladribine with cyclophosphamide and prednisone in the management of low-grade lymphoproliferative malignancies

The feasibility of combining cladribine with cyclophosphamide and prednisone in the management of indolent lymphoid malignancies was determined. Nineteen patients [nine chronic lymphocytic leukaemia (CLL), seven non-Hodgkin's lymphoma (NHL) and three macroglobulinaemia (M))] received cladribine 0.1 mg kg(-1) per day as a subcutaneous bolus injection on days 1-3 (up to 5 injections) with intravenous cyclophosphamide 500 mg m(-2) on day 1 and oral prednisone 40 mg (m-2) on days 1-5 at 4-weekly intervals up to a maximum of six courses. A total of 80 courses were given. Overall response rate was 88%, with four patients achieving a complete clinical and haematological response and 12 achieving a partial response. Neutropenia WHO grade 4 in two patients and WHO grade 3 infection in one patient were the limiting toxicities on treatment. During the follow-up, WHO grade >3 haematological complications occurred in five patients and WHO grade >3 non-haematological complications in five patients. There were no treatment-related deaths. This study demonstrates the feasibility of the cladribine/cyclophosphamide/prednisone (CCP) combination that appears highly active and safe in the management of indolent lymphoid malignancies.     

Treatment of four patients with myelodysplastic syndrome with a small dose of aclacinomycin-A

The effect of a small dose of aclacinomycin-A (ACR) was examined in two patients with refractory anemia (RA) and two with refractory anemia with excess of blasts in transformation (RAEB-t). ACR (7 or 14 mg/m2) was given for 10 days in a 2-h per day drip infusion. Clinical symptoms and laboratory data improved in 3 of these 4 patients. In a patient with RA, marked increase in reticulocytes and elevation of the hemoglobin level from 6 to 9 g/dl was observed after two courses of ACR therapy. In two with RAEB-t, Auer's rod bearing cells disappeared in the bone marrow and megaloblastic change of the erythroblasts was diminished in one patient. Hemoglobin levels rose from 4.7 to 10 g/dl in one, and platelets and WBC increased in another. No effect was seen in a patient with RA. The cytoreductive effect of ACR was minor compared to the therapy with small dose of cytosine arabinoside (Ara-C). Therefore, ACR warrants further consideration for the treatment of patients with MDS.     

5-azacitidine efficacy and safety in patients aged >65 years with myelodysplastic syndromes outside clinical trials

The efficacy and safety of azacitidine in elderly patients (aged >65 years) with myelodysplastic syndromes (MDS) treated outside clinical trials are reported. Thirty-eight patients with MDS received azacitidine (75 mg/m(2), schedule 5+2 +2): seven patients were classified as having refractory cytopenia with multilineage dysplasia (RCMD), nine patients with refractory anemia with excess of blasts (RAEB) type 1, 18 patients with RAEB type 2 and four patients with chronic myelomonocytic leukemia type 2 (CMML-2). According to International Working Group (IWG) 2006 criteria, after the first four cycles we detected complete remission in seven patients (CR, 18%), improvement of bone marrow dysplasia and reduction of blast percentage in seven patients (partial response, 18%), stable disease in 20 patients (53%) and progression to acute leukemia in four patients (10%). Median overall survival for all patients treated was 16.4 months. Only mild non-hematologic toxicity was detected (grade 1-2 nausea and pruritus), whereas 55% of patients experienced hematologic side effects (25% grade 3-4 thrombocytopenia and 30% grade 3-4 neutropenia). Our results suggest that advanced age should not preclude effective treatment with azacitidine in non-selected elderly patients wih MDS.     

The relationship between the myelodysplastic syndromes and the myeloproliferative disorders.

As a result of clonal evolution typical cases of one of the myelodysplastic syndromes may develop myeloproliferative features. Similarly, typical cases of one of the myeloproliferative disorders may develop dysplastic features, either as part of the natural history of the disease or as a result of exposure to mutagenic drugs or isotopes. There is also an important group of "overlap syndromes" in which cases, at presentation, have both dysplastic and proliferative features. Chronic myelomonocytic leukaemia and many cases of atypical chronic myeloid leukaemia, juvenile chronic myeloid leukaemia and the childhood monosomy 7 syndrome are "overlap syndromes". In addition, a significant minority of cases which fit the generally agreed criteria for a diagnosis of one of the myelodysplastic syndromes (refractory anaemia, refractory anaemia with ring sideroblasts or refractory anaemia with excess of blasts) also have thrombocytosis, neutrophilia, monocytosis, eosinophilia or basophilia.     

Combination of low-dose cytarabine and 13-cis retinoic acid in the treatment of myelodysplastic syndromes

Responses have been reported in patients with myelodysplastic syndromes (MDS) after low-dose cytarabine (Ara-C) or 13-cis-retinoic acid (13-CRA) therapy. Recently, combination of these two substances in vitro was shown to produce a synergistic effect on differentiation of leukemic cells. We conducted a phase II trial with low-dose Ara-C (5 mg/m2 per 12 h s.c.) and 13-CRA (60 mg/m2 per day orally) in 14 patients with MDS, six of whom had refractory anemia with excess of blasts (RAEB), seven had RAEB in transformation (RAEBt) and one chronic myelomonocytic leukemia (CMML). The drugs were administered from day 1 to 14 and the treatment courses repeated every 4 to 8 weeks. One partial response and one minor response could be achieved. Major toxicity included dry skin, mucositis and cheilitis in 11 of the 14 patients. The response rate is no better than the results reported in the literature with either drugs alone. As yet there is no satisfactory treatment for MDS.     

Mutational analysis of the KIT gene in myelodysplastic syndrome (MDS) and MDS-derived leukemia

The progenitor cells of myelodysplastic syndrome (MDS) are thought to undergo a multistep process during their transformation into overt acute leukemia. In this study, the role of mutation of the KIT gene in the extracellular membrane, juxtamembrane and tyrosine kinase domains was investigated in 75 patients with MDS or MDS-derived leukemia (MDS-AML). Mutation was detected in 2 of 15 (13.3%) patients with refractory anemia with excess blasts transformation (RAEB-T), in 1 of 15 (6.6%) patients with chronic myelomonocytic leukemia (CMML), and in 5 of 26 (19.2%) patients with MDS-AML. However, no mutation was found in any of the nine patients with refractory anemia (RA) or the 10 patients with refractory anemia with excess blasts (RAEB). Of the mutations, five patients had changes at the same codon in tyrosine kinase domain, Asp816, while the remainder had unique mutations. These observations suggest that KIT gene mutations identified in the advanced stage of MDS, and genetic abnormality in the KIT gene, particularly at codon 816, might be additional events that contribute to the progression of MDS to AML.     

Phase II trial of CPT-11 in myelodysplastic syndromes with excess of marrow blasts.

CPT-11 is an antineoplastic agent which acts as a specific inhibitor of DNA topisomerase 1 and has a broad spectrum of activity in solid tumors. Very few studies have evaluated the activity of CPT-11 in hematological malignancies. We conducted a phase II trial of CPT-11 in 26 patients with high-risk MDS (RAEB 1: n = 4; RAEB 2: n = 9; MDS having progressed to AML: n = 10; CMML: n = 3) who could not receive anthracycline/cytarabine intensive chemotherapy. Induction therapy consisted of four courses of CPT-11 given intravenously at 200 mg/m(2) every 2 weeks. Patient characteristics were: median age, 71 (range 51-77); sex, (M/F), 21/5, median % marrow blasts cells, 13.5 (range 7-52). Cytogenetics according to IPSS were: low-risk n = 13, intermediate-risk n = 6, high-risk n = 3, failure or not done n = 4. Six patients stopped treatment after only one or two courses of CPT-11 due to severe infection (n = 2), progressive disease (n = 3), acute lysis syndrome with renal failure (n = 1). In the 20 patients who received at least three cycles of CPT-11, complete remission was achieved in one case, partial remission in four cases, and hematological improvement in three cases with an overall response rate of 33% in the 26 patients. Duration of response was short (median 4 months, range 1-6 months) and median survival was 8 months (range 1-23 months). Digestive toxicity (diarrhea) occurred in 26/89 (29%) courses, but was mild (grade 1, 20% courses; grade 2 or 3, 9% courses). Hematological toxicity was difficult to assess in non-responders because of initial pancytopenia, but all the patients who responded had grade 3/4 hematological toxicity associated with grade >/=2 infection requiring hospitalization in 18% of the courses. No other major toxicity was observed. Thus CPT-11 has an interesting activity in MDS with excess of blasts; toxicity is easily managed and most patients can be treated in the out-clinic setting. These results suggest that further evaluation of CPT-11 in MDS is warranted.     

Oral 9-cis retinoic acid (Alitretinoin) in the treatment of myelodysplastic syndromes: results from a pilot study.

A multicenter phase II study was initiated to investigate the efficacy, toxicity and tolerability of an oral regimen of 9-cis retinoic acid (9CRA) as a differentiation-inducing agent stimulating both retinoic acid receptor (RAR) and retinoic X receptor (RXR). Thirty patients with myelodysplastic syndromes (MDS) were enrolled into the study. The MDS subtypes were distributed as follows: 14 refractory anaemia (RA), four refractory anaemia with ringed sideroblasts (RARS), and 12 refractory anaemia with excess blasts (RAEB). The age ranged from 40 to 81 years (median 70). None of these had previously received treatment for MDS other than supportive therapy. 9CRA (Alitretinoin capsules, kindly provided by Allergan-Ligand Retinoid Therapeutics) was given daily at 60 mg/m2 p.o. for 1 week, followed by an intra-patient escalation to 100 mg/m2 during the second week, up to a maximum of 140 mg/m2. The planned treatment duration was 48 weeks. Twenty-five were available for assessment. One patient (4%) with RA achieved complete hematological remission. Four (16%), two with RA, two with RAEB, had minor responses resulting in decreased transfusion requirements or increased neutrophils. Thus, the overall response rate was 20% in evaluable patients with MDS and 17% in the study group on an intention-to-treat basis. The most frequent side-effects included headache (77%), dry skin (57%), arthralgias (30%), and rash (23%). In conclusion, although modest responses were noted in this study, the treatment tolerability was suboptimal. It is conceivable that a lower dosage schedule may be efficacious and better tolerated so enabling prolonged exposure which may be required to induce a differentiation effect.     

Single-agent gemcitabine in pretreated patients with non-small-cell lung cancer: results of an Argentinean multicentre phase II trial.

The activity and mild toxicity profile of single-agent gemcitabine therapy in untreated (chemonaive) patients with non-small-cell lung cancer (NSCLC) is well documented. This phase II trial was conducted to determine the objective tumour response rate and toxicity profile of single-agent gemcitabine in pretreated patients with NSCLC. Patients with histological evidence of advanced NCSLC stage IIIB or IV; at least one prior chemotherapy regimen including a platinum or taxane analogue; an Eastern Cooperative Oncology Group (ECOG) performance status of 0-2; clinically measurable disease; adequate bone marrow reserve; and adequate renal function; received 1000 mg m(-2) gemcitabine administered over 30 min on days 1, 8 and 15 of a 28-day cycle defined as 3 weekly treatments followed by 1 week of rest. Twenty-nine patients were evaluated for efficacy and 32 for toxicity. One patient achieved a complete response and five patients had a partial response resulting in a total response rate of 20.6% (95% confidence interval (CI) 6-34). Median response duration was 7 months (range 4-11 months). Twelve (41%) patients reached stable disease after two cycles of therapy and 11 (38%) patients had disease progression. Median progression-free survival time was 3 months and median overall survival time was 5.5 months. Toxicity was generally mild (grades 0-2). Severe (grade 3 or 4) haematological toxicities included grade 3 anaemia in one patient and grade 3 thrombocytopenia in two patients. Severe non-haematological toxicities included one patient each with grade 3 liver transaminase elevations, nausea/vomiting and diarrhoea. This study confirms the activity and safety of single-agent gemcitabine in pretreated patients with advanced NSCLC who are refractory or sensitive to first-line therapy.     

Clinical activity and safety of the dual pathway inhibitor rigosertib for higher risk myelodysplastic syndromes following DNA methyltransferase inhibitor therapy

Rigosertib (ON 01910.Na) is an inhibitor of the phosphoinositide 3‐kinase and polo‐like kinase pathways that induces mitotic arrest and apoptosis in neoplastic cells, while sparing normal cells. Our purpose is to summarize the clinical activity and safety of intravenous (IV) rigosertib delivered by an external ambulatory infusion pump in patients with refractory anemia with excess blasts‐1, ‐2, or, ‐t myelodysplastic syndromes (MDS) following prior treatment with DNA methyltransferase (DNMT) inhibitors. A total of 39 patients with MDS who fulfilled these criteria were enrolled in four phase 1‐2 clinical trials of IV rigosertib. Thirty five (88%) had higher risk disease according to the Revised International Prognostic Scoring System. Median overall survival for this group of 39 patients was 35 weeks. Of 30 evaluable patients with follow‐up bone marrow biopsies, 12 (40%) achieved complete (n = 5) or partial (n = 7) bone marrow blast responses. In addition, 15 patients achieved stabilization of bone marrow blasts. One patient with a complete bone marrow response also achieved a complete cytogenetic response. A second patient with stable bone marrow blasts achieved a partial cytogenetic response. Two of the responding patients and three patients with stable disease had hematological improvements. Rigosertib‐induced bone marrow blast decreases and stability appeared to be predictive of prolonged survival. IV rigosertib had a favorable safety profile without significant myelosuppression. Most common drug‐related toxicities included fatigue, diarrhea, nausea, dysuria, and hematuria. In summary, IV rigosertib is well tolerated and has clinical activity in patients with higher risk MDS following DNMT inhibitor treatment. A multinational pivotal phase 3 randomized clinical trial of rigosertib versus best supportive care for patients with MDS with excess blasts following prior treatment with DNMT inhibitors (ONTIME: ON 01910.Na Trial In Myelodysplastic SyndromE) has recently completed enrollment. © 2014 The Authors. Hematological Oncology published by John Wiley & Sons, Ltd.     

Detection of TNFα expression in the bone marrow and determination of TNFα production of peripheral blood mononuclear cells in myelodysplastic syndrome

TNFalpha is a highly active cytokine which plays an important role in the regulation of apoptotic cell death, a mechanism involved in the pathophysiology of myelodysplastic syndrome (MDS). In this study we investigated the expression of TNFalpha of the bone marrow trephine biopsies by immunohistochemical method and the TNFalpha production of peripheral blood mononuclear cells by ELISA method in 15 patients affected by MDS. Five of seven patients without excess of blasts showed high or intermediate TNFalpha expression in the bone marrow biopsies, whereas two patients with excess of blasts were negative and one had low expression. The five CMML patients revealed low or intermediate expression. The production of TNFalpha by the PBMC was analysed in 10 patients, four patients with RA and two with CMML produced higher level of TNFalpha which increased after stimulation with phorbol myristic acetate, but none of the RAEB patients revealed increase in TNFalpha production. In conclusion we suppose that increased TNFalpha expression and production by PBMC may be an indirect evidence of the role of increased apoptosis in low risk MDS patients.