Background: P53 tumor suppressor gene mutation is one of the most common genetic alterations in human malignancies. The mutated from of the gene is stable and can be detected with immunohistochemistry methods. There is much controversy about the expression rate of this gene in malignant melanoma. Objective: To determine the frequency of the P53 antigen expression by sex, age, type and thickness...

Malignant gliomas are the most common and the most lethal primary brain tumors in adults. Among malignant gliomas, 60%-80% show loss of P14ARF tumor suppressor activity due to somatic alterations of the INK4A/ARF genetic locus. The tumor suppressor activity of P14ARF is in part a result of its ability to prevent the degradation of P53 by binding to and sequestering HDM2. However, the subsequent...

Members of the signal transducers and activators of transcription (STATs) family of proteins, which connect cytokine signaling to activation of transcription, are frequently activated in human cancers. Suppressors of cytokine signaling (SOCS) are transcriptional targets of activated STAT proteins that negatively control STAT signaling. SOCS1 expression is silenced in multiple human cancers sugg...

The tumor suppressor p53 is a multi-functional protein, its functions covering cell cycle control, apoptosis, senescence, genome integrity maintenance, metabolism, cellular reprogramming and autophagy. Regulation of p53 stability is a central process in controlling these p53 functions. Multiple E3 ligases that mediate p53 degradation through the ubiquitination proteasome pathway have been well ...

The INK4a gene encodes two distinct growth inhibitors--the cyclin-dependent kinase inhibitor p16Ink4a, which is a component of the Rb pathway, and the tumor suppressor p19Arf, which has been functionally linked to p53. Here we show that p19Arf potently suppresses oncogenic transformation in primary cells and that this function is abrogated when p53 is neutralized by viral oncoproteins and domin...

Introduction: Gastric carcinogenesis frequently affects tumor suppressor TP53 gene, resulting in increased expression of p53 protein and mutations towards later stages Carcinoma. Objectives: To analyze different gastric cancer to determine if it could be used as a biomarker allow targeted screening high risk groups with intestinal metaplasia. Methods: We retrieved 101 formalin fixed paraffin em...

MDM2 and MDMX are oncoproteins that negatively regulate the activity and stability of the tumor suppressor protein p53. The inhibitors of protein-protein interactions (PPIs) of MDM2-p53 and MDMX-p53 represent potential anticancer agents. In this study, a novel approach for identifying MDM2-p53 and MDMX-p53 PPI inhibitor candidates by affinity-based screening using a chemical array has been esta...

The p53 tumor suppressor gene is frequently mutated and the K-ras oncogene is occasionally mutated in primary specimens of human lung carcinomas. These mutated genes also cooperate in the immortalization and neoplastic transformation of rodent cells. To determine whether these mutations are necessary for maintenance of the immortalized and/or neoplastically transformed states of human bronchial...

Tumor suppressor p53 are frequently mutated in glioblastomas (GBMs) and appears to contribute, in part, to resistance to temozolomide (TMZ) and therapeutic drugs. WW domain-containing oxidoreductase WWOX (FOR or WOX1) is a proapoptotic protein and is considered as a tumor suppressor. Loss of WWOX gene expression is frequently seen in malignant cancer cells due to promoter hypermethylation, gene...