We examined HINT1 and IκBα expression in HCC cell lines and determined the effect of HINT1 overexpression and knockdown on IκBα protein and mRNA expression in these cell lines.
RT-PCR assays revealed that the messenger RNA (mRNA) transcript levels of Hint1 were markedly lower than those of primary HCC tissues and non-metastatic lymph nodes (P < 0.01).
Hypermethylation of Hint1 was evaluated by the methylation specific PCR (MSP) method in 40 patients with HCC (tumor and paired adjacent non-tumor tissues) from Taiwan, 22 cases of normal liver tissue (14 from Taiwan and 8 from the US).
Therefore, decreased expression of the Hint1 gene through epigenetic silencing may play a role in enhancing the growth of a subset of human hepatoma by increasing the expression of genes controlled by the transcription factors beta-catenin, USF2, and NFkappaB.