OBJECTIVETo investigate the mechanisms of the effects of solanine on human androgen-independent prostate cancer cell line PC-3 in vitro.

METHODSPC-3 cells were treated with solanine at the concentration of 0, 30, 40 and 50 microg/ml, and the cell activity was measured by CCK-8 at 12, 24 and 48 hours after the treatment. At 24 hours, the cell cycle and apoptosis were detected by flow cytometry and fluorescence microscopy, and the protein expressions of I(kappa)B(alpha) and Bcl-2 determined by Western blot.

RESULTSSolanine suppressed the growth of PC-3 cells in a dose- and time-dependent manner in vitro, with significant differences among different concentration and time groups (P < 0.05). The cycle of the PC-3 cells was arrested in the S phase (P < 0.05), with a significantly higher rate of apoptosis in the treated groups than in the controls (P < 0.05). The protein expression of I(kappa)B(alpha) was obviously up-regulated and that of Bcl-2 down-regulated in all the solanine concentration groups.

CONCLUSIONSolanine has an anti-prostate cancer effect by inhibiting PC-3 cell proliferation, arresting the S phase, inducing cell apoptosis, up-regulating the protein expression of I(kappa)B(alpha) and down-regulating that of Bcl-2.

Apoptosis ; drug effects ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Humans ; I-kappa B Proteins ; metabolism ; Male ; NF-KappaB Inhibitor alpha ; Prostatic Neoplasms ; metabolism ; pathology ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Solanine ; pharmacology

OBJECTIVETo investigate the effect of solanine on the growth of human prostate cancer cell xenograft in nude mice.

METHODSHuman prostate cancer Du145 cells were injected into the subcutaneous layers on the back of nude mice. After a week, the mice bearing subcutaneous tumor graft were randomly divided into solanine treatment group and saline control group for treatment for 3 weeks. The tumor grafts were then harvested to evaluate the inhibition rate. The mRNA and protein expressions of cell cycle-related genes in the tumors were detected by qRT-PCR and Western blotting, respectively, and tumor cell apoptosis was detected using TUNEL method.

RESULTSThe tumor growth rate in solanine-treated group was significantly slower than that in the control group (P<0.01). The mRNA and protein expressions of C-myc, cyclin D1, cyclin E1, CDK2, CDK4 and CDK6 were significantly inhibited by solanine. Solanine significantly up-regulated p21 mRNA and protein expression in the tumors and induced a higher apoptosis rate of the tumor cells than saline (P<0.01).

CONCLUSIONThe tumor-inhibition effect of solanine is probably mediated by regulating the expressions of genes related with G1/S cell cycle arrest and cell apoptosis.

Animals ; Apoptosis ; Cyclin-Dependent Kinases ; metabolism ; Cyclins ; metabolism ; G1 Phase Cell Cycle Checkpoints ; Humans ; Male ; Mice ; Mice, Nude ; Neoplasm Transplantation ; pathology ; Prostatic Neoplasms ; drug therapy ; pathology ; S Phase ; Solanine ; pharmacology