clinicopathologic study of Ki-67 proliferation index in colorectal carcinoma

To investigate Ki-67 immunoexpressions in colorectal cancer and analyze possible correlations with variable clinicopathological prognostic factors. A cross-sectional study of tissue sections from 50 formalin-fixed and paraffin-embedded tumor specimens were examined at the Histopathology Laboratory of Rezgary Teaching Hospital in Erbil, Iraq between January 2010 and July 2011. Ki-67 labeling index is calculated immunohistochemically using the monoclonal antibody MIB-1, and the standard streptavidin-biotin immunoperoxidase method. The clinicopathologic and prognostic features were statistically analyzed. Over-expression of Ki-67 proliferation protein was found in 31 [62%] cases. Statistical analyses revealed a significant relation between Ki-67 proliferation index and histologic type [p=0.005] and tumor grade [p=0.018]; but no significant relation was calculated with the other clinicopathological parameters such as age, gender, tumor's size, site, depth, stage, nodal status, and vascular invasion [p>0.05]. Ki-67 immune overexpression is a frequent finding in our colorectal cancer cases; but it is not enough to monitor Ki-67 proliferation index alone for prognosis in colorectal cancer

P53 expression in endometrial hyperplasia and endometrial carcinoma

Mutations of the P53 tumor suppressor gene and alterations in its protein expression often occur in a variety of human malignant tumors, including endometrial carcinoma, but the practical implications of this phenomenon are yet to be fully exploited. This study was designed to evaluate P53 protein expression in normal, hyperplastic and malignant endometrium by immunohistochemical study and to correlate P53 expression in endometrial carcinoma with other clinic-pathological prognostic parameters [age, histologic type, tumor grade, cervical and myometrial invasion, and tumor stage]. The studied samples included 100 formalin fixed, paraffin embedded endometrial tissue specimens which were divided to the following diagnostic categories: - Proliferative endometrium [n=10]; secretory endometrium [n=10]; simple hyperplasia [n=10]; complex hyperplasia without atypia [n=20]; atypical complex hyperplasia [n=10] and endometrial carcinoma [n=40]. .None of the normal endometrium, simple hyperplasia and complex hyperplasia without atypia showed P53 immunostaining, while 20% of atypical complex hyperplasia and 32.5% of endometrial carcinoma showed immunoreactivity for P53. In endometrial carcinoma, significant correlation was observed between P53 expression and age at diagnosis, histological grade,FIGO stage, myometrial invasion and cervical invasion; but not with the histological type. The results indicated the validity and simplicity of the application of immunohistochemistry in determining the status of P53 overexpresion which is strongly associated with endometrial carcinoma aggressiveness and high malignant potential

Immunoexpression of p53 and p21 [WAF1/CIP1] proteins in colorectal cancer: correlation with clinicopathological parameters

Both p53 and p21 [WAF1/CIP1] proteins belong to the cell cycle-regulating family of proteins, and the loss of their activity seems to be one of the most important regulatory mechanisms of carcinogenesis in colorectal cancer. The aim of this study was to evaluate the tumor suppressor genes p53 and p21 [WAF1/CIP1] expressions in colorectal cancer and assessment the relationship between p2 [WAF1/CIP1] and p53 immunoreactivity with special emphasis on the prognostic significance of their expression with variable clinicopathologic parameters. Tissue sections from 50 formalin-fixed and paraffin-embedded tumor specimens were examined. The standard streptavidin-biotin immunoperoxidase method was used for immunostaining of p53 protein and p2[WAF1/CIP1] protein.The extent of positive p53 and p21 [WAF1/CIP1] staining was graded semiquantitatively. The clinicopathologic and prognostic features were statistically analyzed. Over-expression of p53 and p2l [WAF1/CIP1] were found in 27 cases [54%] and 22 cases [44%] respectively. Statistical analyses revealed a highly significant correlation between p21 [WAF1/CIP1] and p53 immunopositivity [p=0.003]; but no significant correlation could be calculated between p53 or p21 [WAF1/CIP1] proteins expression with the Clinicopathological parameters such as [age, sex, tumor size, gender, TNM staging, and vascular invasion] except there was significant statistical correlation of p53 expression with tumor type [p<0.05]. Our investigation results suggest that p53 and p2l [WAF1/CIP1] immunoexpression are common findings in colorectal cancer and the induction of p21 [WAF1/CIP1] occur in a p53-dependent or independent pathways