The survival kinase Akt and the tumor suppressor LKB1 elicit opposite effects on cell proliferation and tumorigenesis. The present study demonstrates that Akt acts as an upstream kinase of LKB1 to promote the phosphorylation at Ser334 and facilitate its binding to 14-3-3 proteins, resulting in a decreased interaction with STE20-related adaptor protein α (STRADα) and an enhanced nuclear accumula...

in this archival analysis of genetic & protein alterations in the p53 tumor suppressor gene, we used immunohistochemical methods for detection of these alterations. the tumor series includes: 61 paraffin embedded esophageal squamous cell carcinoma from a high incidence (ethnic) & a non-high incidence regions in iran.

The p53 tumor suppressor protein represents a target for viral and cellular oncoproteins, including adenovirus gene products. Recently, it was discovered that several proteins with structural and functional homologies to p53 exist in human cells. Two of them were termed p51 and p73. We have shown previously that the E1B 55-kDa protein (E1B-55 kDa) of adenovirus type 5 (Ad5) binds and inactivate...

E-cadherin is among tumor suppressor genes which mostly subjects to the down-regulation in squamous cell carcinoma of esophagus (SCCE). The gene is tightly associated with the tumor invasion and metastasis in multiple human cancers, especially SCCE. CpG islands’ methylation in the promoter region of E-cadherin is among the mechanisms that have been suggested for the E-cadherin silencing, howeve...

p53 is an oncosuppressor protein, which acts via transcriptional and non-transcriptional mechanisms. The transcriptional function of p53 is mediated by specific responsive elements. In the present study we found active responsive elements, specific for the p53 within the 5'flanking region and within the first intron of the gene encoding for the CD59 membrane inhibitor of reactive lysis, and wit...

Cells from organisms with renewable tissues can permanently withdraw from the cell cycle in response to diverse stress, including dysfunctional telomeres, DNA damage, strong mitogenic signals, and disrupted chromatin. This response, termed cellular senescence, is controlled by the p53 and RB tumor suppressor proteins and constitutes a potent anticancer mechanism. Nonetheless, senescent cells ac...

p53 is a key tumor suppressor protein that has numerous functions. Its primary mode of action has generally been ascribed to the induction of cell-cycle arrest, apoptosis, or senescence upon stress. Li et al. challenge this dogma with evidence that all three of these programs are dispensable for p53's tumor suppressive role.