It induces cell apoptosis by blocking anti-apoptotic pathways, while inhibiting tumor cell multiplication and malignant transformation through p27-cyclin-E-pRb-E2F1- cell cycle control and HIF-1alphaVEGF antiangiogenic pathways.
Overexpression of p53 may serve as an early risk marker for malignant transformation in HPV infected cells while the overexpression of PCNA may serve as a late marker for progression of LSCC.
We conclude that there was altered expression of p53, Rad50, and cyclin-E in the malignant transformation of gallbladder carcinoma in this methyl isocyanate gas-exposed cohort.
It was concluded that the combination of some biomarkers (additional chromosomes 11, high PCNA and DNA indices) may allow identification of more aggressive colorectal adenomas with increased ability to undergo malignant transformation.
These results suggest that the inactivation of the p16/cdk-cyclin/Rb cascade does not occur during malignant transformation but occurs during the immortalization by HPV in HPV-harbouring premalignant lesions, the in situ equivalent of immortalized cells.
The presence of oncogenic HPV DNAs (HPV-16/18) in cervical carcinomas and their normal and metastatic pelvic lymph nodes and the expression patterns of proliferating cell nuclear antigen (PCNA) in cervical carcinomas were retrospectively studied to elucidate the possible roles of them in malignant transformation and progression of the disease.