"Similarly, Kuenzi et al., have reported increased p53-ser15 phosphorylation but decreased expression of p53 in fungal alkaloid, militarinone A treated N2a cells XREF_BIBR, indicating the activation of p53 by increased phosphorylation at ser15 might reduce p53 level in curcumin treated N2a cells."
"Expression of exogenous Plk1 and p53 in lung carcinoma H1299 cells deficient in p53 greatly decreased the p53 mediated transcription of the p53 responsive p21, MDM2, and BAX promoters, whereas the kinase deficient mutant Plk1 failed to reduce the transcriptional activity of p53 [XREF_BIBR], suggesting that Plk1 mediated negative regulation of p53 might be a fundamental mechanism for the role of Plk1 in oncogenesis."
"While transfection with empty vector and subsequent forskolin treatment again showed significant downregulation of p53 protein, p53 overexpression completely abrogated forskolin induced downregulation of p53 and showed no significant difference in p53 protein levels between forskolin stimulation and vehicle control."
"13 These phenotypes seen in HPV16E6 expressing human cells have been reproduced using other means to inactivate p53 including expression of dominant negative p53 alleles and RNAi mediated depletion of p53 protein expression, XREF_BIBR - XREF_BIBR demonstrating that the phenotypes are likely derived from the effects of HPV16E6 on p53."
"Expression of antisense p53 RNA decreased p53 protein levels and delayed p53 accumulation following c-Myc activation."
"Expression of exogenous Plk1 and p53 in p53 deficient lung carcinoma H1299 cells greatly decreased the p53 mediated transcription from the p53 responsive p21 (WAF1), MDM2, and BAX promoters, whereas the kinase deficient mutant form of Plk1 failed to reduce the transcriptional activity of p53."
"Here we showed that underlying the process of GADD45A kd enhanced chemo-sensitivity, the TP53 expression was decreased not only in wild-type (U87) but also in mutant (U373, T98) TP53 expressing GBM cells."
"By immunoblot analysis, transient expression of p53-shRNA reduced endogenous p53 protein levels by 65%."
"Decreased p53 levels and mutations in p53 have been linked to high incidences of cancer, thus p53 levels being elevated act as a mechanism of tumor suppression."
"U50488HCl alone did not affect p53 expression however, in combination with L-779,976, the p53 levels significantly decreased."
"Interestingly, CD133 + cells were shown to overexpress miR-130b, a miR able to target and to lower the levels of p53 induced nuclear protein 1 (TP53 and NP1) : reducing TP53 and NP1 levels into CD133 + cells, increased their tumorigenicity [XREF_BIBR]."