Abdel-Rahman N. Zekri
Cairo University
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Abdel-Rahman N. Zekri.
BMC Gastroenterology | 2004
Abeer A. Bahnassy; Abdel-Rahman N. Zekri; Soumaya El-Houssini; Amal M. El-Shehaby; Moustafa Raafat Mahmoud; Samira Abdallah; Mostafa El-Serafi
BackgroundColorectal cancer is a common cancer all over the world. Aberrations in the cell cycle checkpoints have been shown to be of prognostic significance in colorectal cancer.MethodsThe expression of cyclin D1, cyclin A, histone H3 and Ki-67 was examined in 60 colorectal cancer cases for co-regulation and impact on overall survival using immunohistochemistry, southern blot and in situ hybridization techniques. Immunoreactivity was evaluated semi quantitatively by determining the staining index of the studied proteins.ResultsThere was a significant correlation between cyclin D1 gene amplification and protein overexpression (concordance = 63.6%) and between Ki-67 and the other studied proteins. The staining index for Ki-67, cyclin A and D1 was higher in large, poorly differentiated tumors. The staining index of cyclin D1 was significantly higher in cases with deeply invasive tumors and nodal metastasis. Overexpression of cyclin A and D1 and amplification of cyclin D1 were associated with reduced overall survival. Multivariate analysis shows that cyclin D1 and A are two independent prognostic factors in colorectal cancer patients.ConclusionsLoss of cell cycle checkpoints control is common in colorectal cancer. Cyclin A and D1 are superior independent indicators of poor prognosis in colorectal cancer patients. Therefore, they may help in predicting the clinical outcome of those patients on an individual basis and could be considered important therapeutic targets.
Virology Journal | 2007
Abdel-Rahman N. Zekri; Mohamed M. Hafez; Nahed I Mohamed; Zeinab K. Hassan; Manal H. El-Sayed; Mohsen M Khaled; Tarek Mansour
BackgroundThere are eight genotypes of hepatitis B virus (A-H) and subgenotypes are recognized. Genotyping can be accomplished based on a partial sequence of HBV genome such as the pre-S or S gene. Several methods have been developed and used for HBV genotyping. This study was undertaken to determine the HBV genotypes in Egyptian pediatric cancer patients with acute and chronic liver disease.MethodsHBV genotypes were determined in 22 patients who had acute forms of liver disease (AH) and in 48 patients with chronic active hepatitis (CAH). A type-specific primer based the nested-PCR method was employed in the HBV genotyping.ResultsThis study showed that HBV infections in pediatric cancer patients are attributed predominantly to viral genotypes D and B that constituted 37.1% and 25.7%, respectively of the total infections. In addition, there was a relatively high prevalence of mixed infections of 15.7% among the studied group especially mixed A/D genotype infections. Genotype D was found significantly more often in patients with CAH than in patients with AH [23/48(47.9%) v 3/22 (13.6%)].ConclusionThese findings show the distribution of HBV A-D genotypes in pediatric cancer Egyptian patients. Furthermore, our results indicate a markedly high prevalence of mixed A/D genotype infections in subjects with CAH and a possible association of mixed infections with the severity of liver diseases.
Journal of Medical Microbiology | 2000
Abdel-Rahman N. Zekri; Abeer A. Bahnassy; Sabry Shaarawy; Ossama A. Mansour; Mohamed A. Maduar; Hussein Khaled; Omer El-Ahmadi
The distribution of hepatitis C virus (HCV) genotypes among Egyptian patients positive for anti-HCV was determined and their influence, when combined with neu-oncoprotein overexpression, on the development of hepatocellular carcinoma (HCC) was examined. The study groups included asymptomatic carriers (ASC) and patients with chronic active hepatitis (CAH) and HCC. HCV genomes were detected in the sera of 27 ASC, 29 CAH and 33 HCC patients known to have HCV infection defined by EIA and recombinant immunoblotting techniques (Inno-LiA) as well as by reverse transcriptase (RT)-PCR. The HCV genotype was determined by a reverse hybridisation technique (Inno-LiPA I and II), whereas neu-overexpression was detected by the Oncogene Science EIA Kit. Eighty-nine patients were eligible for HCV genotyping; 75 patients (84.3%) were infected with a single genotype, including 1a in 11 patients (12.4%), 1b in 2 patients (2.2%) and 2a in 10 patients (11.2%). Genotype 4 (a or c+d) was detected in 51 patients (57.3%) and only one patient had genotype 10a (1.2%). Fourteen patients (15.7%) showed mixed infection; eight of them had 1a+4 (a or c+d) and four had 2a+4 (a or c+d); the remaining two cases had 1a+2a and 1b+2a. The results revealed an increased incidence of genotype 4 in CAH and HCC patients in comparison with ASC. There was also a significant overexpression of neu-oncoprotein in CAH and HCC patients compared with ASC, which was significantly associated with subtype 4 infection. The results suggest that infection with subtype 1a and 4 HCV may be considered a risk factor for the induction of neu-overexpression and subsequent development of HCC.
Urologic Oncology-seminars and Original Investigations | 2003
Hussein Khaled; Abeer A Bahnassi; Abdel-Rahman N. Zekri; Hatem Aboul Kassem; Nadia Mokhtar
Alterations of the p53 tumor suppressor gene are the most common genetic changes detected in human cancers as well as in papillary and invasive bladder cancer. Several studies have demonstrated an association between HPV infection and urological malignancies. In the present work, the p53 gene status was studied together with the frequency of HPV in 99 cases of Bilharzial bladder cancer [BBC] in Egypt and both were correlated to the clinicopathological features of the patients. SSCP and sequencing were used to screen the p53 gene for mutations at exons 4-10 and IHC was performed to detect protein overexpression. PCR was used for detection and typing of HPV-DNA in tumor samples. p53 mutations were detected in 33.3% of the studied cases whereas protein overexpression was detected in 35.6% of the cases. The highest concordance rate was observed in cases harboring mutations at exon 4 [87.5%]. Bilharzial infestation was obvious in 72.2% of the cases that showed mutations. Exon 8 showed the highest rate of mutation [32%] followed by exons 4 and 5 [22% each]. The commonest mutational event was G:C transversion [15/50] especially at CpG dinucleotides. A mutational hot spot was detected at exon 4, codons 72-73. HPV-DNA was detected in 48.97% of the cases the majority of which [64.6%] were of type 16. Significant correlation was found between p53 mutation and the pathological stage as well as p53 overexpression and tumor grade. Our results demonstrate that the mutational spectrum in BBC is different from that of bladder cancer in Western countries in many aspects and suggest an etiological role of HPV in this type of neoplasm. However, both HPV infection and p53 gene abnormalities may contribute to Bilharzial bladder carcinogenesis in an independent way.
Virology Journal | 2009
Abdel-Rahman N. Zekri; Abeer A. Bahnassy; Hanaa M Alam El-Din; Hosny Salama
BackgroundHCV is circulating as a heterogeneous group of quasispecies. It has been addressed that siRNA can inhibit HCV replication in-vitro using HCV clone and/or replicon which have only one genotype. The current study was conducted to assess whether siRNA can inhibit different HCV genotypes with many quasispecies and to assess whether consensus siRNA have the same effect as regular siRNA.MethodsWe generated two chemically synthesized consensus siRNAs (Z3 and Z5) which cover most known HCV genotype sequences and quasispecies using Ambium system. Highly positive HCV patients serum with nine quasispecies was transfected in-vitro to Huh-7 cell line which supports HCV genotype-4 replication. siRNA (Z3&Z5) were transfected according to Qiagen Porta-lipid technique and subsequently cultured for eight days. HCV replication was monitored by RT-PCR for detection of plus and minus strands. Real-time PCR was used for quantification of HCV, whereas detection of the viral core protein was performed by western blot.ResultsHCV RNA levels decreased 18-fold (P = 0.001) and 25-fold (P = 0.0005) in cells transfected with Z3 and Z5, respectively, on Day 2 post transfection and continued for Day 3 by Z3 and Day 7 by Z5. Reduction of core protein expression was reported at Day 2 post Z3 siRNA transfection and at Day 1 post Z5 siRNA, which was persistent for Day 4 for the former and for Day 6 for the latter.ConclusionConsensus siRNA could be used as a new molecular target therapy to effectively inhibit HCV replication in the presence of more than one HCV quasispecies.
Pathology International | 2005
Abeer A. Bahnassy; Abdel-Rahman N. Zekri; Samira Abdallah; Amal M. El-Shehaby; Ghada M Sherif
The etiological role of human papillomavirus (HPV) in esophageal carcinoma (EC) in relation to p53, mdm2, p21waf, c‐erbB2 and the overall survival (OS) rate was investigated. Tumor and normal tissues from 50 EC were evaluated by polymerase chain reaction and InnoLiPA for HPV. Single strand conformation polymorphism/sequencing were used to detect p53 gene mutations. Immunohistochemistry was performed to determine p53, mdm2, p21wafand c‐erbB2 expression. Human papillomavirus was detected in 54% of tumors and in 24% of normal tissues. p53, mdm2 and c‐erbB2 overexpression was detected in 68%, 70% and 60% of tumors and in 14%, 16% and 10% of normal samples, whereas loss of p21waf was evident in 64% of tumors. p53 mutations were detected in 20% of cases. Exon 8 and 5 showed the highest mutation rate (40% each), followed by exons 6 and 7 (10% each). There was a significant correlation between HPV and p53, mdm2, c‐erbB2 overexpression. The OS was significantly associated with overexpression of p53 and loss of p21waf. Human papillomavirus infection is frequent in Egyptian EC. Both p53‐dependent and p53‐independent pathways seem to be involved in HPV‐associated EC. mdm2 and c‐erbB2 are possible targets for HPV in the p53‐independent pathway. However, only advanced stage and aberrant expression of p53 and p21waf are independent prognostic markers.
Comparative Hepatology | 2010
Abdel-Rahman N. Zekri; Hanaa M Alam El-Din; Abeer A. Bahnassy; Naglaa Zayed; Waleed S. Mohamed; Suzan H El-Masry; Sayed K Gouda; Gamal Esmat
BackgroundLiver disease progression from chronic hepatitis C virus (HCV) infection to hepatocellular carcinoma (HCC) is associated with an imbalance between T-helper 1 and T-helper 2 cytokines. Evaluation of cytokines as possible candidate biomarkers for prediction of HCC was performed using soluble Fas (sFas), soluble tumor necrosis factor receptor-II (sTNFR-II), interleukin-2 receptor (IL-2R) and interleukin-8 (IL-8).ResultsThe following patients were recruited: 79 with HCV infection, 30 with HCC, 32 with chronic liver disease associated with elevated liver enzyme levels (with or without cirrhosis) in addition to 17 with chronic HCV with persistent normal alanine aminotransferase levels (PNALT). Nine normal persons negative either for HCV or for hepatitis B virus were included as a control group. All persons were tested for sFas, sTNFR-II, IL-2R and IL-8 in their serum by quantitative ELISA. HCC patients had higher levels of liver enzymes but lower log-HCV titer when compared to the other groups. HCC patients had also significantly higher levels of sFas, sTNFR-II and IL-2R and significantly lower levels of IL-8 when compared to the other groups. Exclusion of HCC among patients having PNALT could be predicted with 90% sensitivity and 70.6% specificity when sTNFR-II is ≥ 389 pg/ml or IL-8 is < 290 pg/ml.ConclusionsSerum TNFR-II, IL-2Rα and IL-8, may be used as combined markers in HCV-infected cases for patients at high risk of developing HCC; further studies, however, are mandatory to check these findings before their application at the population level.
Cancer | 2010
Mostafa El-Serafi; Abeer A. Bahnassy; Nasr M. Ali; Salem Eid; Mahmoud M. Kamel; Nayera A. Abdel‐Hamid; Abdel-Rahman N. Zekri
The prognosis for patients with colorectal cancer (CRC) depends mainly on standard clinicopathologic factors. However, patients with similar disease characteristics exhibit various outcomes, especially in stage II. Therefore, the identification of molecular prognostic markers is needed to predict patient outcomes.
Journal of Gastroenterology and Hepatology | 2009
Abdel-Rahman N. Zekri; Abeer A. Bahnassy; Sabrin Abdel-Wahab; Medhat Khafagy; Samah A. Loutfy; Hessam Radwan; Sabry Shaarawy
Background: Hepatocellular carcinoma (HCC) is one of the most common tumors worldwide strongly linked to hepatitis C virus (HCV) infection. However, the exact pathogenetic mechanisms are still unclear.
Medical Oncology | 2010
Sanaa Eissa; Samir F. Zohny; Abdel-Rahman N. Zekri; Tarek Mostafa El-Zayat; Amany M. Maher
Development of new methods for bladder cancer detection is required because cystoscopy is invasive, and voided urine cytology (VUC) has low sensitivity. The aim of this study was to evaluate the diagnostic performance of urinary fibronectin and mutant p53 in comparison with VUC in the detection of bladder cancer. This study included 100 patients diagnosed with bladder cancer, 93 patients with benign urological disorders and 47 healthy volunteers. The urine supernatant was used for determination of fibronectin by ELISA, while urine sediment was used for cytology and detection of mutant p53 by PCR-SSCP followed by DNA sequencing. The sensitivity and specificity were 59% and 91.4% for VUC, 82% and 84.3% for fibronectin, and 37% and 100% for mutant p53; combination of the three parameters increased sensitivity to 95% but specificity was only 78.6%. A significant association was observed between disease recurrence and mutant p53, stage and lymph node involvement. Our results indicate that fibronectin had the highest sensitivity compared to VUC and mutant p53 in bladder cancer detection; however, mutant p53 had superior specificity compared to VUC and fibronectin. Mutant p53 is associated with disease recurrence and hence it has a significant prognostic role in bladder cancer.