OBJECTIVETo investigate the effect of Zilongjin (ZLJ) on human androgen-dependent type of prostate cancer cell line LNCaP.

METHODSMTT assay, flow cytometry and fluorescence microscopy were used to observe the effect of ZLJ in anti-proliferation, cell cycle arresting and apoptosis induction. RT-PCR was used to examine the effect of ZLJ on expressions of prostate marker gene (PSA), androgen receptor (AR), apoptosis related genes (bcl-2 and bax), and Western blot assay was used to detect the effect on protein expression of bcl-2 and bax.

RESULTSZLJ could cause apparent inhibition on proliferation, induce G0/G1 phase arresting and apoptosis in time- and dose-dependent manner on LNCaP cells. The concentration for inhibiting cell growth by 50% (IC50) in 72 hrs was 0.79 mg/ml. ZLJ could down-regulate the expression of PSA, AR, bcl-2 genes and lower bcl-2 protein expression, but showed ineffective on bax protein expression.

CONCLUSIONZLJ displays its anti-tumor effects by way of inhibiting the cell proliferation, arresting the G0/G1 phase, inducing apoptosis, down-regulating PSA, AR, bcl-2 gene expression and lowering bcl-2 protein expressions.

Antineoplastic Agents, Phytogenic ; pharmacology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Humans ; Male ; Neoplasms, Hormone-Dependent ; metabolism ; pathology ; Prostate-Specific Antigen ; biosynthesis ; genetics ; Prostatic Neoplasms ; metabolism ; pathology ; Proto-Oncogene Proteins c-bcl-2 ; biosynthesis ; genetics ; Receptors, Androgen ; biosynthesis ; genetics