The mdm2 gene is positively regulated by p53 through a p53-responsive DNA element in the first intron of the mdm2 gene. mdm2 binds p53, thereby abrogating the ability of p53 to activate the mdm2 gene, and thus forming an autoregulatory loop of mdm2 gene regulation. Although the mdm2 gene is thought to act as an oncogene by blocking the activity of p53, recent studies indicate that mdm2 can act ...

KAI1 is a tumor metastasis suppressor gene that is capable of inhibiting the metastatic process in animals. The expression of the KAI1 gene also is found to be down-regulated during the tumor progression of prostate, breast, lung, bladder, and pancreatic cancers in humans, and this down-regulation appears to be at or posttranscription level. We have found that the tumor suppressor gene p53 can ...

Zebrafish carrying heterozygous mutations for 17 different ribosomal protein (rp) genes are prone to developing malignant peripheral nerve sheath tumors (MPNSTs), a tumor type that is seldom seen in laboratory strains of zebrafish. Interestingly, the same rare tumor type arises in zebrafish that are homozygous for a loss-of-function point mutation in the tumor suppressor gene p53. For these rea...

OBJECTIVE To determine the frequency of p53 gene mutation and protein expression in Oral Squamous Cell Carcinoma (OSCC) and to establish correlation between the two. STUDY DESIGN Analytical study. PLACE AND DURATION OF STUDY Histopathology Department and Molecular Biology Laboratory, Armed Forces Institute of Pathology (AFIP), Rawalpindi, from May 2010 to May 2011. METHODOLOGY Thirty diag...

BACKGROUND Alterations in the p53 tumor suppressor gene constitute one of the most frequent genetic events associated with the development of human cancers. Determination of an individual's p53 status may be of value in early diagnosis, prediction of response to treatment, and for the detection of minimal residual cancer. Recent studies have also revealed that specific mutations affecting the p...

The p53 tumor suppressor gene is an important target for the gene therapy of cancers, and clinical trials targeting this gene have been conducted. Some cancers, however, are refractory to p53 gene therapy. Therefore, it has been combined with other therapies, including chemotherapy and radiotherapy, to enhance the cytopathic effect of p53 induction. The p33 gene cooperates with p53 to block cel...

Abortive infection of BALB/c mouse embryo fibroblasts differing in p53 gene status (p53(+/+) versus p53(-/)(-)) with simian virus 40 (SV40) revealed a quantitatively and qualitatively decreased transformation efficiency in p53(-/-) cells compared to p53(+/+) cells, suggesting a supportive effect of wild-type (wt) p53 in the SV40 transformation process. SV40 transformation efficiency also was lo...

To elucidate the biological significance of the p53 gene expression in human hepatocellular carcinoma (HCC), the p53 protein was studied in 184 resected unifocal primary HCCs, including 102 small (< or = 5 cm) and 82 large HCCs (> 5 cm), using immunocytochemistry. The p53 mRNA expression was analyzed in 69 cases using Northern hybridization. The p53 protein, which was detected in 58 HCCs (31.5%...

Overexpression of wild-type p53 gene in malignant cell iines has been shown to inhibit cell proliferation in a number of cases. However, endogenous p53 protein seems to play little role in normal cell-cycle control as suggested by the normal development of p53 null mice, and by the low p53 protein levels expressed in most cell types. Recently, increased expression of endogenous p53 protein has ...