Human telomerase reverse transcriptase [hTERT] gene expression in thyroid carcinoma: diagnostic and prognostic role

The catalytic component of telomerase, human telomerase reverse transcriptase [hTERT] has been found to be reactivated in immortalized cell lines and considered as a diagnostic marker for malignancy in different body tissues. Therefore we thought to determine whether hTERT gene detection could serve as an adjunct in the diagnosis of thyroid lesions together with evaluation of its prognostic value. The study included 50 cases of primary thyroid carcinoma including; 28 papillary carcinoma, 14 follicular carcinoma, 5 anaplastic carcinoma and 3 medullary carcinoma in addition to 5 cases of nodular hyperplasia and 5 cases of follicular adenoma. RNA was extracted from paraffin sections of those patients and hTERT gene expression was identified by Reverse Transcription-Polymerase Chain Reaction [RT-PCR]. RT-PCR of hTERT gene revealed expression in 43/50 [86%] malignant thyroid cases; including 25 papillary, 11 follicular, 4 anaplastic and 3 medullary carcinoma cases. On the other hand, hTERT gene expression could not be detected in either hyperplastic nodule or in follicular adenoma cases. The diagnostic validity of hTERT gene detection in benign and malignant thyroid lesions was in the form of 88.3% accuracy, 86% sensitivity, 100% specificity, 100% positive predictive value and 90% negative predictive value. No significant association has been found between hTERT gene expression and any clinicopathologic parameters concerned in this study. In thyroid carcinoma cases, hTERT gene detection was the most independent predictor of poor survival by multivariate survival analysis. Detection of hTERT gene expression should be considered in confirmation of malignant thyroid lesions. Moreover it could be one of the helpful tools in addition to grade, tumor type, and age to stratify patients with thyroid carcinoma into different prognostic categories. Hence, inhibition of hTERT could be of use prospectively in the era of cancer therapy as an attractive weapon in thyroid carcinoma

p53 Mutation in HCV-genotype-4 associated hepatocellular carcinoma in Egyptian patients

HCV-associated hepatocellular carcinoma [HCC] is a common neoplasm in Egypt where genotype-4 is prevalent. In the present study the incidence and pattern of p53 mutations was assessed in relation to HCV-genotype-4 in Egyptian HCC patients. We investigated 25 HCV positive HCCs for p53 mutations over expression in relation to HCV-N53 by immunohistochemistry, SSCP and sequencing. Genotyping was done using LiPA-Il and TRUGENE 5 NC sequencing kit. Results were correlated to standard clinicopathologic prognostic factors for HCC. Thirteen cases showed p53 overexpression, and 10 showed p53 mutation [13 mutations] by sequencing [72% concordance]. The highest mutation rate was in exons 6 and 7 [30%] followed by exons 5 and 8 [20%]. Mutations included 3 transitions, 5 transversions, 3 deletions, and 2 insertions. All exon 7 mutations were at codon 249 specific for AFB1 [AGG-AGT, Arg-Ser] and codon 248 specific for vinyl chloride contamination [CGG-TGG, Arg-Trp]. Other mutations reported are novel. Immunostaining for HCV N53 was detected in 19 cases independent of p53 mutation. p53 aberrations were significantly associated with poor prognostic factors for HCC. However, no specific pattern for p53 mutations was observed in HCV genotype 4-associated HCC and no significant relation between p53 mutations, HCV-N53 expressions or any HCV sub-genotype-4 sequence

Estimation of time passed since death by ultrastructure, histopathology and DNA degradation detection by gel electrophoresis in albino rats

The estimation of postmortem interval [PMI] is of great importance in both criminal and civil cases. However this aim remains critical, difficult if not impossible but an imprecise task in forensic investigation. While the traditional thanatochronological changes upon the dead had been used for estimation of PMI inaccurately, advances in molecular biology, have propelled the analysis of DNA to criminal laboratories. Upon the death of an individual, internal nucleases contained within the cell should cause chromosomal DNA to degrade into increasingly smaller fragments over time that can be used as a predictor of PMI. Liver cells for being rich in nuclear DNA and mitochondria were proved to be the best material for the purpose. The aim of the work was to determine the time passed since death by measuring the rate of DNA degradation in samples of livers of albino rats at different post mortem intervals by using gel electrophoresis method, and to asses the changes of liver cells by histopatological examination at the same periods, with exploring the nature of the post mortem liver cell changes by using the Transmission Electron Microscope [TEM]. Passive engorgement of the sinusoids and extravasations of blood elements appeared early after death in histopathology then cell necrosis, shrunken cells, and apoptotic bodies were increasing by time. TEM examinations revealed the presence of chromatin condensations and fragmentation of the nuclear material. Finally cell lysis and apoptotic bodies appeared while cell necrosis was prominent. Electron microscope could add much to understanding postmortem cellular changes, also assessment of the relative existence of necrosis stages in histopathology might help in identifying PMI. The Gel Electrophorsis detection, measurement and analysis by computer pro analyzer revealed the presence of sequential relationship between DNA degradation level and time passed since death at the DNA visualizing positions [200 bp, 400 bp, 600 bp] up to 24 hours. Statistical evaluation showed a highly significant dependence of DNA degradation on time with P < 0.001. By using linear regression analysis an equation to define the time passed since death could be conducted where: Time after death=[DNA degradation - constant] / B. So it is recommended to apply the method of the gel electrophoresis to detect time passed since death by measuring DNA fragmentation from liver cells. These mathematical relations offer a simple and valuable means of estimating the PMI, and its validity should be tested for human being

Prognostic value of cyclin Dl and P53 protein in colorectal carcinoma

The multistep carcinogenic process of colorectal cancer involves a series of events as oncogenes, inactivation of suppressor genes and abnormalities in cell cycle regulating proteins. This study concerns altered expression and prognostic role of cyclin Dl and p53 in colorectal cancer patients. We evaluate nuclear accumulation of cyclin Dl and p53 immunohistochemically in archival tissue specimens from 41 primary colorectal adenocarcinomas. They had undergone surgery with a median follow up of 23 months [range 1-85 months]. Survival time was analyzed using Kaplan-Meier survival estimates and Cox proportional hazards model for nuclear accumulation of cyclin Dl and p53 with adjustments for other confounding demographic and clinical variables. The expression of cyclin Dl was identified in 41.5% while p53 was expressed in 58.5% of our cases. Cyclin Dl was statistically associated with p53, Dukes stage, nodal state, histologic grade and vascular invasion, but not with age, gender, location, size, gross picture, tumor type, bilharziasis or stromal reaction. p53 was significantly related to male gender and to mucinous and signet ring tumor types but not to either age, location, size gross picture, Dukes stage, nodal state, histologic grade, bilharziasis, stromal reaction or vascular invasion. Using Kaplan-Meier survival curve, cyclin Dl, p53, size, Dukes stage, nodal state and tumor type were significantly correlated with poor survival. By Cox multivariate regression analysis, p53 [relative risk 3.33, 95%-confidence interval 1.39-7.95; p=0.006], nodal state [relative risk 3.17, 95% confidence interval 1.31-7.68; p=0.01] and Dukes stage [relative risk 1.83, 95% confidence interval 1.06-3.15; p=0.027] were independent prognostic indicators in our colorectal adenocarcinoma cases. Our data suggest that cyclin D1/p53 pathway represent a frequent target of the multistep evolution of colorectal carcinoma. Nuclear p53 accumulation combined with nodal state and Dukes stage can predict the clinical behavior of a tumor and high risk colorectal cancer patients. Hence p53 might help to define, a subset of biologically unfavorable neoplasms and improve the prognostic accuracy for colorectal cancer