The role of lymphoid tissue SPARC in the pathogenesis and response to treatment of multiple myeloma.

Background: Despite the significant progress in the treatment of multiple myeloma (MM), the disease remains untreatable and its cure is still an unmet clinical need. Neoplastic transformation in MM is initiated in the germinal centers (GCs) of secondary lymphoid tissue (SLT) where B cells experience extensive somatic hypermutation induced by follicular dendritic cells (FDCs) and T-cell signals. Objective: We reason that secreted protein acidic and rich in cysteine (SPARC), a common stromal motif expressed by FDCs at the origin (SLTs) and the destination (BM) of MM, plays a role in the pathogenesis of MM, and, here, we sought to investigate this role. Methods: There were 107 BM biopsies from 57 MM patients (taken at different time points) together with 13 control specimens assessed for SPARC gene and protein expression and compared with tonsillar tissues. In addition, regulation of myeloma-promoting genes by SPARC-secreting FDCs was assessed in in vitro GC reactions (GCRs). Results: SPARC gene expression was confirmed in both human primary (BM) and secondary (tonsils) lymphoid tissues, and the expression was significantly higher in the BM. Sparc was detectable in the BM and tonsillar lysates, co-localized with the FDC markers in both tissues, and stimulation of FDCs in vitro induced significantly higher levels of SPARC expression than unstimulated controls. In addition, SPARC inversely correlated with BM PC infiltration, ISS staging, and ECOG performance of the MM patients, and in vitro addition of FDCs to lymphocytes inhibited the expression of several oncogenes associated with malignant transformation of PCs. Conclusion: FDC-SPARC inhibits several myelomagenic gene expression and inversely correlates with PC infiltration and MM progression. Therapeutic induction of SPARC expression through combinations of the current MM drugs, repositioning of non-MM drugs, or novel drug discovery could pave the way to better control MM in clinically severe and drug-resistant patients.

The Influence of Interleukin-2 Gene Polymorphisms on the Risk and Clinical Outcome of Non-Hodgkin Lymphoma.

Polymorphisms in the IL-2 gene are associated with various diseases and cancers including non-Hodgkin lymphoma (NHL). The aim of the study is to assess the impact of IL-2 genetic polymorphisms [- 330 T/G (rs2069762) and + 114 T/G (rs2069763)] on the susceptibility and prognosis of NHL. Sixty patients with NHL as well as 60 age and sex matched healthy control subjects are included in this study. IL-2 genotypes were determined by Polymerase Chain Reaction-Restriction Fragment length Polymorphism assay (PCR-RFLP). Our study revealed that both IL-2 rs2069762 and rs2069763 gene polymorphisms are associated with increased risk of developing NHL; OR = 3.609 (95% CI = 1.527-8.417) and 4.142 (95% CI = 1.637-10.538) respectively. Moreover, the simultaneous presence of both polymorphisms is associated with about 6 fold increased risk of developing NHL. Also, IL-2 rs2069762 and rs2069763 gene polymorphisms increase the risk of unfavorable prognosis with OR = 17.300 (95% CI = 3.392-87.725) and 10.424(95% CI = 1.870-58.413) respectively. These findings suggest that IL-2 (rs2069762) and (rs2069763) gene polymorphisms could be involved in the development of NHL.

Expression pattern and prognostic implication of SALL4 gene in myeloid leukemias: a case-control study.

SALL4 is a transcription factor that retains stem cells in an undifferentiated state and promotes its self-renewal. In addition, it is implicated in leukemogenesis via its effect on leukemic stem cells. This study aimed to characterize the expression pattern of SALL4 gene in acute myeloid leukemia (AML) and chronic myeloid leukemia (CML) at different progression phases of the leukemic process and to assess its prognostic significance. Real-time PCR was used in 106 patients: 54 AML patients; 43 de novo and 11 in complete remission (CR), 52 CML patients; 31 in chronic phase (CP), 11 in deep molecular response (MR4) and 10 in accelerated/blastic phase (AP/BP); and in 21 nonmalignant bone marrow samples. SALL4 gene expression was elevated in AML, AML-CR and CML-CP (median = 5.180, 4.604 and 14.125 fold changes, respectively). Elevated SALL4 gene expression among AML de novo patient was associated with poor disease-free survival (DFS) rates (p = .022). Among CML patients, the highest percentage of patients with a high SALL4 (p = .033) was among CML-CP. SALL4 has a role in leukemogenesis; high SALL4 expression was associated with poor DFS among AML patients.

The clinical relevance and prognostic significance of adenosine triphosphate ATP-binding cassette (ABCB5) and multidrug resistance (MDR1) genes expression in acute leukemia: an Egyptian study.

AIM: Multidrug resistance (MDR1) represents a major obstacle in the chemotherapeutic treatment of acute leukemia (AL). Adenosine triphosphate ATP-binding cassette (ABCB5) and MDR1 genes are integral membrane proteins belonging to ATP-binding cassette transporters superfamily. PURPOSE: The present work aimed to investigate the impact of ABCB5 and MDR1 genes expression on the response to chemotherapy in a cohort of Egyptian AL patients. The study included 90 patients: 53 AML cases and 37 ALL cases in addition to 20 healthy volunteers as controls. METHODS: Quantitative assessment of MDR1 and ABCB5 genes expression was performed by quantitative real-time polymerase chain reaction. Additional prognostic molecular markers were determined as internal tandem duplications of the FLT3 gene (FLT3-ITD) and nucleophosmin gene mutation (NPM1) for AML cases, and mbcr-abl fusion transcript for B-ALL cases. RESULTS: In AML patients, ABCB5 and MDR1 expression levels did not differ significantly between de novo and relapsed cases and did not correlate with the overall survival or disease-free survival. AML patients were stratified according to the studied genetic markers, and complete remission rate was found to be more prominent in patients having low expression of MDR1 and ABCB5 genes together with mutated NPM1 gene. In ALL patients, ABCB5 gene expression level was significantly higher in relapsed cases and MDR1 gene expression was significantly higher in patients with resistant disease. CONCLUSION: In conclusion, the results obtained by the current study provide additional evidence of the role played by these genes as predictive factors for resistance of leukemic cells to chemotherapy and hence treatment outcome.

A descriptive study of plasma cell dyscrasias in Egyptian population.

BACKGROUND: Plasma cell dyscrasias (PCDs) refer to a spectrum of disorders characterized by the monoclonal proliferation of lymphoplasmacytic cells in the bone marrow and, sometimes, tissue deposition of monoclonal immunoglobulins or their components. These disorders include multiple myeloma (MM) and Waldenström's macroglobulinemia, as well as rare conditions such as light-chain deposition disease (LCDD) and heavy-chain diseases (HCDs). The worldwide annual incidence of MM is estimated at 86,000, which is approximately 0.8% of all new cancer cases. PURPOSE: Our retrospective study aims to highlight the immunologic and epidemiological features of PCDs mainly MM in Egyptian patients and compare our results with those of other populations. METHODS: Two hundred seventeen Egyptian patients with PCD were enrolled in the study. Serum, urine protein electrophoresis and immunofixation were used to demonstrate M protein. RESULTS: One hundred thirty-eight patients (63.6%) had IgG monoclonal band, 38 patients (17.5%) had IgA, 12 patients (5.5%) had Waldenström's macroglobulinemia (IgM monoclonal band) and 29 patients (13.4%) were light chain myeloma. One hundred fifty-one (70%) were Kappa chain positive and 66 patients (30%) were lumbda positive. Conventional cytogenetics was available for 40 patients; of them12 patients (30%) showed 13q-. Mean OS was 37.5months (1-84months). Survival analysis was statistically insignificant according to age, sex and ISS or type of treatment (P value>0.05). CONCLUSION: Long term follow up is required to further define the role of different therapeutic lines of treatment including ASCT in the various stages of PCD based on OS data.

CCAAT/enhancer binding protein α gene expression in Egyptian patients with acute myeloid leukemia.

BACKGROUND: Transcription factors play a crucial role in myeloid differentiation and lineage determination. Tumor suppressor protein C/EBPa is a key regulator of granulocytic differentiation whose functional inactivation has become a pathophysiological signature of myeloid leukemia. Given the role that CCAAT/enhancer binding protein α (C/EBP α) plays in myelopoiesis, we anticipated that their expression might be disrupted in myeloid neoplasms. PURPOSE: To estimate the expression of C/EBPα mRNA in patients with acute myeloid leukemia and correlate its expression with the pathogenesis of the disease. PATIENTS AND METHODS: Forty AML patients and 20 age and sex matched healthy controls were included in the study. Blood samples of patients and controls were analyzed for CEBPα mRNA expression by quantitative RT-real time PCR using TaqMan technology & ΔΔCt method for calculation of gene expression. RESULTS: Twenty-nine (72.5%) patients out of the 40 showed low expression levels of CEBPα mRNA below the cutoff value with median of 0.19 (range:0-0.87). While eleven (27.5%) patients out of the 40 showed higher expression levels of CEBPα above the cutoff value with median of 1.52 (range:1.07-2). Seven patients out of the 11 showed higher expression levels of CEBPα mRNA belong to the M3 subtype of AML harboring the t(15;17) PML-RARa translocation. CONCLUSION: We conclude that the majority of the AML patients analyzed, express low levels of C/EBPa mRNA. However, a subset of patients represented by the M3 subtype, express higher levels of C/EBPa.

The association between hepatitis C virus infection, genetic polymorphisms of oxidative stress genes and B-cell non-Hodgkin's lymphoma risk in Egypt.

Hepatitis C virus (HCV) has been postulated to be an etiological agent for lymphoid malignancies. Polymorphisms in oxidative stress genes as; superoxide dismutase (SOD2), glutathione peroxidase (GPX1), catalase (CAT), myeloperoxidase (MPO) and nitric oxide synthase (NOS2) may influence non-Hodgkin's lymphoma (NHL) risk. HCV screening and polymorphisms in these five genes coding for antioxidant enzymes were studied in 100 Egyptian patients with B cell-NHL and 100 controls to clarify the association between HCV infection, oxidative stress genes polymorphisms and B cell-NHL risk. A significantly higher prevalence of HCV infection was detected among NHL patients relative to controls and this carried a 14-fold increased NHL risk (odds ratio (OR)=14.3, 95% confidence interval (CI)=5.4-38.3, p<0.0001). GPX1 and MPO genetic polymorphisms conveyed increase in B-NHL risk (OR=3.3, 95% CI=1.4-7.4, p=0.004 and OR=4.4, 95% CI=1.3-14.2, p=0.009 respectively). Further analyses stratified by HCV infection revealed that concomitant HCV infection and GPX1 gene polymorphism had a synergetic effect on NHL risk with an OR of 15 (95%CI=2.2-69.6, p<0.0001). In addition, combined HCV infection and MPO gene polymorphisms had a pronounced NHL risk (OR=9.2, 95%CI=2.5-33.9, p<0.0001). SOD2, CAT and NOS2 genetic polymorphisms were not found to confer increased NHL risk. This study revealed that HCV infection is a risk factor for NHL in Egypt. Polymorphisms in GPX1 and MPO genes may influence NHL risk in HCV infected Egyptian patients. Larger scale studies are warranted to establish this genetic susceptibility for NHL.

Modification and implementation of NCCN guidelines on lymphomas in the Middle East and North Africa region.

In the Middle East and North Africa (MENA) region, cancer has many epidemiologic and clinical features that are different from those in the rest of the world. Additionally, the region has a relatively young population and large disparities in the availability of resources at diagnostic and treatment levels. A critical need exists for regional guidelines on cancer care, including those for lymphoid malignancies. A panel of lymphoma experts from MENA reviewed the 2009 version of the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) on Non-Hodgkin's Lymphoma and Hodgkin Lymphoma and suggested modifications for the region that were discussed with the United States NCCN Lymphoma Panels. This article presents the consensus recommendations.