Cyclopentadione-aniline conjugate suppresses proliferation and induces apoptosis in liver cancer cells via up-regulation of p38 phosphorylation

Abstract

Purpose: To investigate the effect of cyclopentadione-aniline conjugate (CAC) on proliferation of liver cancer cells. Methods: MTT assay and flow cytometry were used for the determination of the effect of CAC on cell proliferation and apoptosis. Western blotting was used to measure the influence of CAC on the expressions of various proteins, while Matrigel-coated Transwell assay was used for assessment of cell invasion. Results: CAC inhibited proliferation of liver cancer cells in a concentration-dependent manner. The degree of proliferation of HepG2 cells was 98, 89, 76, 66, 51, 42 or 36 %, on treatment with 0.25, 0.5, 1.0, 1.5, 2.0, 2.5 or 3.0 µM CAC, respectively. In H4TG cells, treatment with 0.25, 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 µM CAC decreased proliferation of cells to 99, 91, 79, 70, 54, 46 and 40 %, respectively. Apoptosis was induced in 34.56, 37.37 and 52.98 % cells, on treatment with 2.0, 2.5 and 3.0 µM CAC, respectively. The invasive potential of HepG2 cells was significantly decreased by CAC (p < 0.05). Marked decreases were observed in Bcl-2, MMP-2, MMP-9, c-ERK1/2 and phospho-Akt levels in CACtreated HepG2 cells. CAC treatment markedly upregulated Bax and phospho ERK1/2, but significantly downregulated phospho PI3K, phospho mTOR and phospho Akt in HepG2 cells (p < 0.05). However, the level of phospho p38 was decreased in CAC-treated cells. Conclusion: These results demonstrate that CAC inhibits proliferation of liver cancer cells via apoptosis induction. Thus, CAC can potentially be used for the treatment of liver cancer in humans