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Dive into the research topics where Abeer A. Bahnassy is active.

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Featured researches published by Abeer A. Bahnassy.


BMC Gastroenterology | 2004

Cyclin A and cyclin D1 as significant prognostic markers in colorectal cancer patients

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.


Cell Transplantation | 2010

Autologous Hematopoietic Stem Cell Transplantation in 48 Patients With End-Stage Chronic Liver Diseases

Hosny Salama; Abdel Rahman Zekri; Mark A. Zern; Abeer A. Bahnassy; Samah A. Loutfy; Sameh Shalaby; Cheryl Vigen; Wendy S. Burke; Mohamed Mostafa; Eman Medhat; Omar Alfi; Elizabeth Huttinger

The only presently viable treatment for end-stage liver disease is whole organ transplantation. However, there are insufficient livers available. The aim of the present study is to provide autologous bone marrow-derived stem cells as a potential therapeutic for patients with end-stage cirrhosis. This is a retrospective chart review of autologous stem cell treatment in 48 patients, 36 with chronic end-stage hepatitis C-induced liver disease and 12 with end-stage autoimmune liver disease. For all patients, granulocyte colony-stimulating factor was administered to mobilize their hematopoietic stem cells. Following leukapheresis, CD34+ stem cells were isolated, amplified, and partially differentiated in culture, then reinjected into each subject via their hepatic artery or portal vein. Treatment was generally well tolerated with the expected moderate but transient bone pain from G-CSF in less than half of the patients. Three patients had serious treatment-related complications, and only 20.8% of these end-stage liver disease patients died during 12 months of follow up. For all patients there was a statistically significant decrease in ascites. There was clinical and biochemical improvement in a large percentage of patients who received the transplantation. In the viral group, there were marked changes in albumin (p = 0.0003), bilirubin (p = 0.04), INR (p = 0.0003), and ALT levels (p = 0.02). In the autoimmune group, values also improved significantly for albumin (p = 0.001), bilirubin (p = 0.002), INR (p = .0005), and ALT levels (p = 0.003). These results suggest that autologous CD34+ stem cell transplantation may be safely administered and appears to offer some therapeutic benefit to patients with both viral and autoimmune-induced end-stage liver disease.


BMC Clinical Pathology | 2007

The possible role of cell cycle regulators in multistep process of HPV-associated cervical carcinoma

Abeer A. Bahnassy; Abdel Rahman Zekri; Maha Saleh; Mohammad Lotayef; Manar Moneir; Osama Shawki

BackgroundHuman papillomavirus (HPV) 16 and 18 are associated with cervical carcinogenesis through an interaction between HPV oncogenic proteins and cell cycle regulatory genes. However, the exact pathogenetic mechanisms are not determined yet.MethodsWe investigated 43 invasive squamous cell carcinoma (ISCC), 38 CIN III, 11 CINII and 18 CINI for cyclin D1, cyclin E, CDK4, p53, mdm-2, p21waf, p27, p16INK 4A, Rb and Ki-67 aberrations using immunohistochemistry and molecular techniques. Twenty samples of normal cervical tissues (NCT) were taken as a control.ResultsThere was a significant increase in the expression of Ki-67, cyclin E, CDK4, p16INK 4A, Rb (p= 0.003, 0.001, 0.001, 0.01) and a significant decrease in p27KIP 1from NCT to ISCC (p = 0.003). Increased cyclin D1, p21waf, p53, mdm-2 expression, homozygous deletion (HZD) and promoter methylation (PM) of the Rb were detected in CINIII and ISCC only. On univariate analysis; tumor size, differentiation, lymph node status, FIGO stage, Ki- 67, cyclin D1, p53 and p27KIP 1are significantly associated with reduced overall survival (OS) while on multivariate analysis; only FIGO stage, Ki-67, cyclin D1, p53 and p27KIP 1were significant.Conclusion1) Aberrations involving p27KIP 1, cyclin E, CDK4, p16INK 4Aare considered early events in HPV 16 and 18-associated cervical carcinoma, whereas cyclin D1 and p53 pathway abnormalities are considered late events. 2) Immunohistochemical tests for p16INK 4Aand cyclin E, could help in early diagnosis of cervical carcinoma. 3) Only FIGO stage p53, cyclin D1, p27KIP 1and Ki-67 are independent prognostic factors that might help in predicting outcome of cervical cancer patients.


Journal of Medical Microbiology | 2000

Hepatitis C virus genotyping in relation to neu- oncoprotein overexpression and the development of hepatocellular carcinoma

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.


Virology Journal | 2009

Consensus siRNA for inhibition of HCV genotype-4 replication.

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

Human papillomavirus infection in Egyptian esophageal carcinoma: Correlation with p53, p21waf, mdm2, C-erbB2 and impact on survival

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

Serum levels of soluble Fas, soluble tumor necrosis factor-receptor II, interleukin-2 receptor and interleukin-8 as early predictors of hepatocellular carcinoma in Egyptian patients with hepatitis C virus genotype-4

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

The Prognostic Value of c-Kit, K-ras Codon 12, and p53 Codon 72 Mutations in Egyptian Patients With Stage II Colorectal Cancer

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

Expression of pro‐ and anti‐inflammatory cytokines in relation to apoptotic genes in Egyptian liver disease patients associated with HCV‐genotype‐4

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.


Asian Pacific Journal of Cancer Prevention | 2013

Disease progression from chronic hepatitis C to cirrhosis and hepatocellular carcinoma is associated with increasing DNA promoter methylation

Abd E.l.Rahman N.abawy Zekri; Auhood Nassar; Mahmoud N. El-Rouby; Hend Ibrahim Shousha; Ahmed Barakat; Eman El-Desouky; Naglaa Zayed; Ola Sayed Ahmed; Amira Salah El-Din Youssef; Ahmed O.mar Kaseb; Ashraf O.mar Abd El-Aziz; Abeer A. Bahnassy

BACKGROUND Changes in DNA methylation patterns are believed to be early events in hepatocarcinogenesis. A better understanding of methylation states and how they correlate with disease progression will aid in finding potential strategies for early detection of HCC. The aim of our study was to analyze the methylation frequency of tumor suppressor genes, P14, P15, and P73, and a mismatch repair gene (O6MGMT) in HCV related chronic liver disease and HCC to identify candidate epigenetic biomarkers for HCC prediction. MATERIALS AND METHODS 516 Egyptian patients with HCV-related liver disease were recruited from Kasr Alaini multidisciplinary HCC clinic from April 2010 to January 2012. Subjects were divided into 4 different clinically defined groups - HCC group (n=208), liver cirrhosis group (n=108), chronic hepatitis C group (n=100), and control group (n=100) - to analyze the methylation status of the target genes in patient plasma using EpiTect Methyl qPCR Array technology. Methylation was considered to be hypermethylated if >10% and/or intermediately methylated if >60%. RESULTS In our series, a significant difference in the hypermethylation status of all studied genes was noted within the different stages of chronic liver disease and ultimately HCC. Hypermethylation of the P14 gene was detected in 100/208 (48.1%), 52/108 (48.1%), 16/100 (16%) and 8/100 (8%) among HCC, liver cirrhosis, chronic hepatitis and control groups, respectively, with a statistically significant difference between the studied groups (p-value 0.008). We also detected P15 hypermethylation in 92/208 (44.2%), 36/108 (33.3%), 20/100 (20%) and 4/100 (4%) , respectively (p-value 0.006). In addition, hypermethylation of P73 was detected in 136/208 (65.4%), 72/108 (66.7%), 32/100 (32%) and 4/100 (4%) (p-value <0.001). Also, we detected O6MGMT hypermethylation in 84/208 (40.4%), 60/108 (55.3%), 20/100 (20%) and 4/100 (4%), respectively (p value <0.001. CONCLUSIONS The epigenetic changes observed in this study indicate that HCC tumors exhibit specific DNA methylation signatures with potential clinical applications in diagnosis and prognosis. In addition, methylation frequency could be used to monitor whether a patient with chronic hepatitis C is likely to progress to liver cirrhosis or even HCC. We can conclude that methylation processes are not just early events in hepatocarcinogenesis but accumulate with progression to cancer.

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Abdel-Rahman N. Zekri

National Institutes of Health

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