BACKGROUND The prognostic significance of p53 aberration in hepatocellular carcinoma (HCC) remains inconclusive. This systematic review and meta-analysis aimed to provide comprehensive evidence on the association of p53 alterations with recurrence-free survival (RFS) and overall survival (OS) in HCC patients. METHODS Systematic literature searches were conducted until July 2010. Meta-analysis...

Coordinate loss of one copy of the p53 gene and mutation of the remaining copy occur in colorectal carcinomas and in many other human malignancies. However, the prevalence of p53 gene mutations in carci nomas which maintain both parental copies of p53 has not previously been evaluated. Moreover, it is not known whether p53 gene mutations are limited to malignant tumors or whether they can also ...

The p53 tumor suppressor gene is critical in regulating cell prolifera tion following DNA damage, and disruption of p53 protein function by mutation has been implicated as a factor responsible for resistance of tumor cells to chemotherapeutic agents. Our studies were initiated by asking whether the translational product otthepSS gene is associated with cisplatin resistance in the 2780CP human o...

p53 is a frequent target for mutation in human tumors, and mutant p53 proteins can actively contribute to tumorigenesis. We employed a three-dimensional culture model in which nonmalignant breast epithelial cells form spheroids reminiscent of acinar structures found in vivo, whereas breast cancer cells display highly disorganized morphology. We found that mutant p53 depletion is sufficient to p...

Mutations of p53 gene occur in approximately 50% of human cancers, and accumulated p53 protein may be an appropriate target molecule to use for cancer immunotherapy. Indeed, mutated or nonmutated p53-derived peptides can induce HLA class I-restricted and tumor cell-reactive CTLs in vitro. However, to our knowledge, evidence that p53-derived peptides are truly recognized by CTLs at tumor sites h...

Mice with a germ line p53 mutation (p53(Ala135Val/wt)) display increased susceptibility to lung, skin, and colon carcinogenesis. Here, we show that p53(Ala135Val/wt) mice developed ovarian tumors significantly more rapidly than their wild-type littermates after 7,12-dimethylbenz(a)anthracene (DMBA) treatment. Approximately 50% of the ovarian tumors in p53(wt/wt) mice and 23% in p53(Ala135Val/wt...

P53 is considered one of the most important defense proteins against cancer.Although the p53 mutation is associated with many cancers, its mutation is never found in Kaposi’s sarcoma (KS), raising a possibility that functional p53 may play a role in KS development. To assess the role of p53 in Kaposi’s sarcoma tumor, shRNA-mediated gene silencing was used to knockdown p53 expression. We examine...

Little is known about the genetic and molecular events leading to the early stages of human astrocytoma formation. To examine this issue, we analyzed the significance of sequential accumulation of two somatic point mutations (R267W and E258D) in the TP53 gene during the initiation of astrocytoma in a patient born with a single germ-line p53 point mutation (R283H). We adapted a p53 transcription...

Coordinate loss of one copy of the p53 gene and mutation of the remaining copy occur in colorectal carcinomas and in many other human malignancies. However, the prevalence of p53 gene mutations in carci nomas which maintain both parental copies of p53 has not previously been evaluated. Moreover, it is not known whether p53 gene mutations are limited to malignant tumors or whether they can also ...

Oncogenic transformation by adenovirus E1A and E1B-55K requires E1B-55K inhibition of p53 activity to prevent E1A-induced apoptosis. During viral infection, E1B-55K and E4orf6 substitute for the substrate-binding subunits of the host cell cullin 5 class of ubiquitin ligases, resulting in p53 polyubiquitinylation and proteasomal degradation. Here we show that E1B-55K alone also functions as an E...