Search results for "Yin Yang 1"

Frequent Alteration of the Yin Yang 1/Raf-1 Kinase Inhibitory Protein Ratio in Hepatocellular Carcinoma

2011

The transcription factor Yin Yang 1 (YY1) can favor several aspects of tumorigenesis. In turn, Raf-1 Kinase Inhibitor Protein (RKIP) inhibits the oncogenic activities of MAPK and NF-κB pathways and promotes drug-induced apoptosis. Mutual influences between YY1 and RKIP may exist, and there are already separate evidences that relevant increases in YY1 and reductions in RKIP occur in hepatocellular carcinoma (HCC). However, the levels of the two factors have never been concomitantly examined in HCC. We evaluated by RT-PCR the mRNA levels of YY1, YY1AP, RKIP, and survivin in 35 clinical HCCs (91% HCV-related), in their adjacent cirrhotic tissues and in 6 healthy livers. Immunohistochemical ana…

Yin Yang 1 and raf-1 Kinase Inhibitory Protein Status in Hepatocellular carcinoma: Future Perspectives

2010

We focus on to the role of the transcription factors NF-κB and Yin Yang 1 (YY1) and of Raf-1 kinase inhibitory protein (RKIP) in hepatocellular carcinoma (HCC). YY1, whose expression is enhanced by NF-κB, favors tumorigenesis. RKIP inhibits the oncogenic activities of MAPK and NF-κB pathways and promotes drug-induced apoptosis. Mutual influences between YY1 and RKIP may exist and there is separate evidence that relevant increases in YY1 and reductions in RKIP occur in HCC. In a recent study on clinical HCC, we found that, indeed, the ratio of YY1 to RKIP mRNA and protein expression is very frequently profoundly inverted in tumors compared with adjacent tissues. Hyperactivation of YY1 in tum…

Alteration of the YY1/RKIP ratio is a frequent event in hepatocellular carcinoma

2009

Induction of Apoptosis and Chemosensitization by the Histone Deacetylase Inhibitor Trichostatin in Hepatocellular Carcinoma Cells: Molecular Analysis…

2011

The mRNA and protein levels of RKIP are reduced and those of YY1 increased in clinical HCC. Loss, mutation, or promoter hypermethylation of the RKIP gene may not account for the downregulation of RKIP in HCC. Histone deacetylation can silence gene expression and play a significant role in hepatocarcinogenesis. The histone deacetylase inhibitor (HDACI) trichostatin induced cell growth inhibition and proapoptotic effects in HA22T/VGH and HepG2 HCC cells; it also exhibited synergy with doxorubicin. Treatment with trichostatin caused histone hyperacetylation and down- or upregulated expression of different genes (such as β-catenin, cyclin D1, hTERT, XIAP, and IL-6). These changes might, at leas…