BMI1 gene expression in myeloid leukemias and its impact on prognosis.

BACKGROUND: BMI1 is a polycomb group (PcG) protein and is overexpressed in leukemia. It plays a key role in the self-renewal of stem cells. Leukemic cells lacking BMI1 underwent proliferation arrest and showed signs of differentiation and apoptosis. AIM: This study was aimed to investigate the expression and impact of BMI1 in myeloid leukemias. Expression levels of BMI1 in 100 acute myeloid leukemia (AML), 100 chronic myeloid leukemia (CML) patients and 20 healthy controls were measured by real time quantitative polymerase chain reaction (RQ-PCR). RESULTS: The results showed that the expression of BMI1 was significantly higher in AML and CML versus control subjects (p<0.001 for both). The 2-year overall and disease free survival rates were significantly lower in patients expressing higher BMI1. Multivariate analysis showed that BMI1 was independent prognostic factor for OS for AML cases (p=0.015, HR=3.204, 95% CI=1.250-8.212). Accelerated and blastic phases in CML cases expressed higher BMI1 than chronic phase (p<0.001). CONCLUSION: We concluded that detecting BMI1 is helpful for predicting the survival in AML patients and monitoring the aggressiveness and progression in patients with CML.

Reverse hybridization StripAssay detection of beta-thalassemia mutations in northeast Egypt.

AIM: beta-Thalassemias are widely distributed in Mediterranean and Middle Eastern countries. Reverse hybridization StripAssay method is reported to be rapid, simple, reproducible and less expensive. The aim of this study is to evaluate reverse hybridization StripAssay method for detection of beta-thalassemia mutations in Egyptian children. SUBJECTS AND METHODS: Forty children with beta-thalassemia major with mean age of 10.33+/-4.75 years were recruited consecutively from outpatient Hematology Clinic of Mansoura University Children's Hospital. Mutation analysis was performed by the beta-Globin StripAssay MED. RESULTS: The most frequent mutant alleles detected were; IVS 1.110, IVS 1.1 and IVS 1.6 accounting for 33.75, 27.5 and 18.75% respectively. The detection rate of the used method in our population was 90%. CONCLUSION: beta-globin StripAssay is a fast, easy-to-perform and reliable method for genetic screening of beta-thalassemia patients in Egypt. IVS 1.110, IVS 1.1 and IVS 1.6 are the most frequent mutant alleles with poor phenotype/genotype correlation.

Clinical significance of antibody to hepatitis B core antigen in multitransfused hemodialysis patients.

BACKGROUND: In spite of the progress made in the prevention of transfusion transmitted infections over the last few years, transmission of HBV infection through transfusion of HBsAg negative blood has been documented. OBJECTIVES: To assess the frequency and clinical significance of anti-HBc in multitransfused hemodialysis patients. MATERIALS AND METHODS: One hundred and forty-three hemodialysis patients who had been receiving blood regularly with an average of 39.4 +/- 7.579 months on hemodialysis were enrolled in this study. HBV markers (HBsAg, anti-HBc, anti-HBs) were measured in these patients and in 100 healthy controls by the ELISA technique. The following data were obtained for all patients: socio demographic data, number of blood transfusions and some laboratory investigations. RESULTS: In our patients, anti-HBc was positive in 9%, anti HBs in 7%, coexistant HbsAg/anti-HBc in 2.8% and anti HBc/anti HBs in 18.9%, meanwhile no patients were positive for HBsAg alone. In patients with only positive anti-HBc, the levels of anti-HBc were significantly related to abnormal results of liver function. In patients with positive anti-HBs/anti-HBc (n = 27), 18 patients had abnormal liver function, and 9 patients had normal liver function with no significant difference between them. CONCLUSIONS: This study suggests that hepatitis B prevalence in our multitransfused hemodialysis patients is far in excess of that anticipated on the basis of HBsAg prevalence. Absence of HBsAg in the blood of hemodialyzed patients may not be sufficient to ensure lack of circulating HBV, and isolated positivity of anti-HBc may be a possible indicator of active hepatitis B infection.

Frequency and prognostic significance of murine double minute protein-2 overexpression and p53 gene mutations in childhood acute lymphoblastic leukemia.

AIM: Determination of frequency and prognostic significance of murine double minute protein-2 (MDM-2) over expression and its association with p53 status in children with acute lymphoblastic leukemia (ALL). METHODS: MDM-2 expression by flow cytometry and p53 gene status by PCR were determined in peripheral blood or bone marrow of 46 ALL children (at initial diagnosis) and control group. RESULTS: MDM-2 was significantly overexpressed in 15 patients (32.6%). p53 mutation was detected in six out of 46 patients at initial diagnosis, three of them were out of 29 cases achieving complete remission (CR) and the other three cases were out of 17 of relapsed patients, which is significantly higher than CR group (P<0.05). Positive correlation was found between the MDM-2 overexpression and initial WBCs count, peripheral blast cell count and presence of CNS blasts (P<0.05, <0.05 and <0.05 respectively). CONCLUSION: MDM-2 is overexpressed in a significant number of childhood ALL, and more often observed in the poor outcome group and its frequency is not related to p53 status. Measurement of MDM-2 as a bad prognostic marker even in cases with non-mutant p53 is very important. Moreover, MDM-2 may be a potential molecular target for production of new cancer therapy.

Prognostic implication of N-RAS gene mutations in Egyptian adult acute myeloid leukemia.

The pathogenesis of acute myeloid leukemia (AML) involves the cooperation of mutations promoting proliferation/survival and those impairing differentiation. Point mutations of the N-RAS gene are the most frequent somatic mutations causing aberrant signal-transduction in acute myeloid leukemia (AML). The aim of the present work is to study the frequency and prognostic significance of N-RAS gene mutations (N-RASmut) in de novo Egyptian adult AML. Bone marrow specimens from 150 patients with de novo acute myeloid leukemia and controls were analyzed by genomic PCR-SSCP at codons 12, 13 (exon 1), and 61 (exon 2) for N-RAS mutations. In 12.7% (19/150) AML cases, N-RAS gene mutations were found and were observed more frequently in the FAB subtype M4eo (P = 0.028) and with codon 12, 13 (14 of 19; 73.7%). Patients with N-RAS mutation had a significant lower peripheral and marrow blasts (P = 0.004, P = 0.03) and clinical outcome did not improve more than in patients without mutation. In patients with N-RAS gene mutation vs. those without, complete remission rate was (63.2% vs. 56.5%; P = 0.46), resistant disease (15.8% vs. 23.6%; P = 0.51), three years overall survival (44% vs 42%; P= 0.85) and disease free survival (42.1% vs. 38.9%, P = 0.74). Multivariate analysis showed that age was the strongest unfavorable factor for overall survival (relative risk [RR], 1.9; P = 0.002), followed by cytogenetics (P = 0.004). FAB types, N-RAS mutation and leukocytosis were the least important. In conclusion, the frequency and spectrum of N-RAS gene mutation differ between biologically distinct subtypes of AML but do not significantly influence prognosis and clinical outcome in patients with AML.

Prevalence and prognostic significance of murine double minute protein-2 overexpression and P53 gene mutations in childhood acute lymphoblastic leukemia.

The murine double minute protein-2 (MDM-2) oncogene is a determinant of embryogenesis, tumorigenesis, and cell cycle progression. The effects of MDM-2 on these processes depend, in part, on its ability to inactivate the p53 tumor suppressor gene. Our goal was to determine whether MDM-2 protein overexpressions or p53 gene mutations are a frequent event in poor outcome pediatric acute lymphoblastic leukemia (ALL). This work was conducted on 46 children with ALL (31 males and 15 females) with age range 2-18 years, 18 children with matched age and sex were enrolled in the study as a control group. The MDM-2 expression by flowcytometry and p53 gene status by PCR were determined in peripheral blood or bone marrow of ALL children (at initial diagnosis) and also of control group. The ALL children were treated by the modified BFM 76179 protocol of therapy, 29 patients (63%) achieved complete remission, while 17 patients (37%) were subsequently failed to achieve complete remission or relapsed within 6 months of achieving complete remission (CR). MDM-2 was significantly overexpressed in 15 ALL patients (32.6%), compared to that of healthy controls, 4 of them (4/15), were out of 29 cases of CR (13.8%), and the other 11 cases were out of 17 relapsed cases (64.7%). In contrast to overexpression of MDM-2, the mutation of p53 was detected in 6 (13%) out of 46 ALL patients at the initial time of diagnosis, 3 of them (10.3%) were out of 29 cases of CR and the other 3 cases (17.6%) were out of 17 of relapsed group, which is significantly higher than CR group (P < 0.05). In relapsed group, 2 patients out of 3 cases with p53 mutation were MDM-2 negative, also, all 3 cases of mutant P53 among patients in CR were negative MDM2. A positive correlation was found between the MDM-2 overexpression and initial WBCs count, blast cell counts in peripheral blood and presence of CNS blasts (p < 0.05, p < 0.05 and p < 0.05 respectively). These results indicate that MDM-2 is overexpressed in a significant number of childhood ALL, it is more frequent in relapsed cases and its frequency is not related to p53 status. Thus measuring of MDM-2 as a bad prognostic marker even in cases with non mutant P53 is very important. Moreover, MDM-2 may be a potential molecular target for production of new cancer therapy.

A study for evaluation of different diagnostic approaches in acute leukemia in Egypt.

Cytomorphology, cytochemistry, immunophenotyping, in addition to cytogenetic and molecular analyses have specific roles in the diagnosis and management of acute leukemias. This work was designed as a comparative study of different available methods for diagnosis of acute leukemia. The study comprised 47 cases with acute leukemia (21 cases with ALL and 26 cases with AML). Peripheral blood and bone marrow samples were subjected to through morphological examination of Leishman-stained smears, cytochemical analysis, immunophenotyping, conventional cytogenetic banding analysis, fluorescence in situ hybridization (FISH) for selected cases, and RT-PCR for detection of BCR-ABL rearrangement. The results of the study revealed that careful examination of Romanowsky-stained peripheral blood and BM films is fundamental in the diagnosis of acute leukemias, and when considered together with clinical and hematological features, indicates which of the more specialized techniques are most likely to be useful. The major role of cytochemistry was in the diagnosis of AML, while the major role of immunophenotyping was in the diagnosis of acute leukemia, which is not obviously myeloid. Apart from identification of chromosomal abnormalities unique to specific subtypes of leukemia, cytogenetic analysis had a salient impact on anticipating the prognosis and treatment outcome in acute leukemias. We could conclude that the techniques used in this study are considered complementary rather than alternatives and that stepwise employment of strategies is more cost effective than doing all the tests simultaneously.