Inhibitory effects ofN-(4-hydrophenyl) retinamide on liver cancer and malignant melanoma cells

Abstract

To investigate the effect of N-(4-hydrophenyl) retinamide (4-HPR), the derivative of retinoic acid, on inhibition of migration, invasion, cell growth, and induction of apoptosis in hepatocellular carcinoma cells (HCCs) and malignant melanoma cells. 4-HPR was chemically synthesized. Cellular migration and invasion were assayed by Borden chamber experiment. Cell growth was assayed by MTT chromometry. Apoptosis effect was measured using Hoechst 32258 staining and flow cytometry. Gene transfection was performed with lipofectamine. We observed that the migration of HCC and melanoma cells was significantly suppressed by 4-HPR and the migration cells were reduced to 58+/-5.03 (control 201+/-27.2, P<0.05, n = 4) in SMMC 7721-k3 HCC, and to 254+/-25.04 (control 302+/-30.1, P<0.05, n = 4) in melanoma cells after 6-h incubation with 4-HPR. The invasion through reconstituted basement membrane was also significantly reduced by 4-HPR treatment to 11.2+/-3.3 in SMMC 7721-k3 HCC (control 27+/-13.1), and to 24.3+/-3.2 in melanoma cells (control 67.5+/-10.1, P<0.05, n = 3). Cell growth, especially in melanoma cells, was also significantly inhibited. Furthermore, 3 micromol/L of 4-HPR induced apoptosis in B16 melanoma cells (37.11+/-0.94%) more significantly than all-trans retinoic acid (P<0.05), but it failed to induce apoptosis in SMMC 7721-k3 HCC. The mechanism for 4-HPR-induced apoptosis was not clear, but we observed that 4-HPR could regulate p27(kip1), and overexpression of cerebroside sulfotransferase (CST) diminished the apoptosis induced by 4-HPR in melanoma cells. 4-HPR is a potent inhibitor of HCC migration and inducer of melanoma cell apoptosis. CST and p27(kip1) expression might be associated with 4-HPR-induced apoptosis.