ABSTRACT
The effect of curcumin on JAK-STAT signaling pathway was investigated in hepatoma cell lines Huh7 and Hep3B. Curcumin inhibited cell proliferation and induced apoptosis of both cell lines, but Huh7 cells were more sensitive to curcumin than Hep3B cells. Curcumin (50 micromol x L(-1)) significantly increased phosphorylations of p38 (T180/Y182) and STAT-1 (S727) in Huh7 and Hep3B cells, and caused relocalization of phosphorylated-STAT-1 (Y701) from cytoplasm to nucleus in Hep3B cells. In addition, curcumin (25 and 50 micromol x L(-1)) dramatically suppressed the phosphorylation level of STAT-1 (Y701) and resulted in a significant reduction of nuclear phosphorylated-STAT-1 (Y701) in Huh7 cells.
Subject(s)
Humans , Antineoplastic Agents, Phytogenic , Pharmacology , Apoptosis , Carcinoma, Hepatocellular , Metabolism , Pathology , Cell Line, Tumor , Cell Proliferation , Curcuma , Chemistry , Curcumin , Pharmacology , Janus Kinases , Metabolism , Liver Neoplasms , Metabolism , Pathology , Phosphorylation , Plants, Medicinal , Chemistry , STAT1 Transcription Factor , Metabolism , Signal Transduction , p38 Mitogen-Activated Protein Kinases , MetabolismABSTRACT
In the present study, shRNA plasmid of pSi-p21 targeting p21 mRNA was constructed and the effect of p21 shRNA on curcumin-induced apoptosis of human hepatoma Huh7 cells was investigated. The effect of curcumin on the expression of p21 mRNA and protein and the silence efficiency of pSi-p21 were detected with RT-PCR and Western blotting. The effect of pSi-p21 on curcumin-induced apoptosis of Huh7 cells was evaluated with DAPI staining. The results showed that curcumin significantly upregulated p21 mRNA and protein expression, which was knocked down by pSi-p21 of Huh7 cells. DAPI staining results showed that pSi-p21 significantly decreased curcumin-induced apoptosis of Huh7 cells. The data suggested that curcumin induced apoptosis of Huh7 cells via upregulation of p21 expression.