Expression of Enhancer of Zeste Homolog 2 (EZH2) Gene in Acute Myeloid Leukemia.

BACKGROUND: Enhancer of Zeste Homolog 2 (EZH2) is the catalytic subunit of the chromatin modifying enzyme polycomb repressive complex 2 (PRC2). As a complex, these proteins selectively silence target genes through trimethylation of histone 3 at lysine 27. EZH2 is strongly oncogenic. It has been observed in various malignancies which makes it an interesting therapeutic target. Whether it functions as a tumor suppressor or oncogene in acute leukemia is not settled. Aim of this work: This study aimed at determining the expression levels of EZH2 gene in a cohort of adult Egyptian patients newly diagnosed with acute myeloid leukemia (AML). MATERIALS AND METHODS: The present study included 45 de novo AML patients and 40 healthy subjects of matched age and sex as a control group. All study participants were subjected to complete blood count (CBC), bone marrow examination, immunophenotyping, conventional cytogenetic studies and Detection of EZH2 gene expression levels by real time quantitative polymerase chain reaction (RQ-PCR). RESULTS: EZH2 was significantly downregulated in AML patients compared to controls (p<0.001). There was no significant difference in EZH2 level when considering age, sex, bone marrow blasts count, cytogenetic studies, type or site of infection. Low EZH2 expression was associated with higher mortality (31 patients, 68.9%). CONCLUSIONS: Low EZH2 expression is prevalent in Egyptian AML patients subsequently; it is suggested to function as tumor suppressor gene rather than an oncogene. Moreover, EZH2 downregulation is associated with resistance to chemotherapy and high mortality rate.

Prognostic Significance of Long Non Coding RNA ANRIL and SNHG14 in Acute Myeloid Leukemia.

BACKGROUND: Long non-coding RNAs (lnRNAs) play a pivotal role in various malignancies including AML. Therefore, we decided to study both lnRNA ANRIL and lnRNA SNHG14 gene expressions in patients with AML to better understand their role in AML risk development, clinical presentation, and prognosis. METHODS: The current prospective study included two hundred participants, 100 AML patients and 100 control subjects. Bone marrow analysis was made to all patients, in addition to gene expression molecular testing of both lnRNA ANRIL and lnRNA SNHG14. RESULTS: Both lnRNA SNHG14 and lnRNA ANRIL showed high expression levels in AML bone marrow samples compared to non-AML subjects and were remarkably associated with lower Complete Remission (OR: 3.449, 95% CI: 1.324-8.985, p=0.011 for ANRIL and OR: 3.955, 95% CI: 1.510-10.356, p=0.005 for SNHG14), Relapse Free Survival (HR=3.504, 95%CI: 1.662-7.387, p=0.001 for ANRIL and HR=4.094, 95%CI: 1.849-9.067, p=0.001 for SNHG14) and Overall Survival (HR=3.353, 95%CI: 1.434-7.839, p=0.005 for ANRIL and HR=3.094, 95%CI: 1.277-7.494, p=0.012 for SNHG14), favouring poor prognostic significance in AML. CONCLUSION: This suggests that both lnRNA ANRIL and lnRNA SNHG14 could be used in the future as prognostic biomarkers to help in treatment decisions and follow up of AML patients.

Evaluation of CD160 and CD200 Expression as Differentiating Markers between Chronic Lymphocytic Leukemia and Other Mature B-Cell Neoplasms.

Background: The present work aimed to investigate the expression of CD160/ CD200 in CLL and other mature B-cell neoplasms (MBN) and their use as an additional diagnostic tool for differentiating CLL from other MBN. Materials and Methods: Using flow cytometry, we detected the expression of CD160 &CD200 on B-cells from 30 CLL patients, 30 other MBN patients in addition to 20 controls. CDs160/200 measurements were determined as a percentage expression (≥20% was considered positive) and as a ratio of the mean fluorescence intensities (MFIR) of leukemic cells/controls and were considered positive when the ratios were ≥2 and 20, respectively. Results: 90% and 100% of the CLL group expressed CDs160/200 in comparison to 60% and 63.3% of other MBN (p=0.007, p<0.001), respectively. By MFIR, 96.7% and 50% of our CLL group expressed CDs160/200 in comparison to 76.7% and 30% of other MBN, respectively. CDs160/ 200 were not expressed on the controls. Positive co-expression of CD160 and CD200 was found in 90% of the CLL cases, 60% of HCL patients and only in 40% of B-NHL. However, double negative expression of both markers was found only in 24% of the B-NHL patients. Conclusion : CD160 with CD200 can be used as additional diagnostic markers to the available routine panel to differentiate between B-CLL and other non-specified B-NHL patients.

The clinical and prognostic significance of FIS1, SPI1, PDCD7 and Ang2 expression levels in acute myeloid leukemia.

OBJECTIVES: The marked heterogeneity of acute myeloid leukemia (AML) renders precisely predicting patient prognosis extremely difficult. Genetic alterations, fusions and mutations, may result in misexpression of key genes in AML. We aimed to investigate the expression patterns of 4 novel genes; FIS1, SPI1, PDCD7 and Ang2 to determine their potential prognostic role in AML patients. METHODS: Bone marrow mononuclear cells were analyzed for of FIS1, SPI1, PDCD7 and Ang2 expression levels by real-time quantitative PCR as well as of FLT3/ITD and NPM1 mutations in 100 newly diagnosed cytogenetically normal (CN-AML) patients, and 100 non-malignant controls. RESULTS: FIS1, SPI1, PDCD7 and Ang2 were significantly overexpressed in CN-AML patients (p < 0.001). Their high expression levels were significantly associated with lower complete remission (CR) rate, shorter relapse-free survival (RFS) and overall survival (OS). On multivariate analysis, high FIS1 expression showed a significant impact on CR response after induction therapy (OR = 88.777, 95% C.I: 2.85-2765.78, p = 0.011) while high PDCD7 appeared to be an independent risk factor for RFS (HR = 5.107, 95% C.I: 1.731-15.066, p = 0.003) and OS (HR = 7.353, 95% C.I: 1.859-29.079, p = 0.004) in CN-AML patients. CONCLUSIONS: FIS1 and PDCD7 expression are considered independent risk factors and should be integrated into the current AML stratification system.

Evaluation of Interleukin-9 Expression as a Potential Therapeutic Target in Chronic Lymphocytic Leukemia in a Cohort of Egyptian Patients.

Chronic lymphocytic leukemia (CLL) is a common lymphoid malignancy that has a highly variable clinical course. Genomic features as zeta-chain-associated protein kinase 70 (ZAP70) expression and CD38 expression provide further differentiation of disease prognosis. Extensive studies have confirmed the oncogenic activities of IL-9 in lymphoma. The aim of the current study was to investigate the contribution of IL-9 expression to the pathogenesis of CLL and its correlation to other prognostic parameters. This study was conducted on 80 patients at diagnosis with CLL and 80 healthy controls. Using real time polymerase chain reaction and enzyme linked immunosorbant assay, IL-9 mRNA expression and its serum level were compared between patients and controls. They were both correlated with other prognostic factors. RESULTS: There was an overexpression of IL-9 in CLL patients that correlated with modified Rai staging, ZAP70, CD38 and all hallmarks of an active and aggressive disease. The correlation between IL-9 upregulation and patient characteristics provided direct clinical evidence for its contribution to the pathogenesis of CLL. In conclusion, significantly higher expression of IL-9 measured at both the mRNA and the protein levels in patients with CLL that correlates with more complex course of the disease and worse prognosis may allow one to speculate its importance in the pathogenesis of the disease and its possible impact on prognosis.