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Updated: Sep 26, 2026

An Orthotopic Murine Model of Human Prostate Cancer Metastasis
Published on: September 18, 2013
PC-SPES inhibits cell proliferation by modulating p21, cyclins D, E and B and multiple cell cycle-related genes in
Xiaohua Lu1, Junqiao Guo, Tze-chen Hsieh
1Department of Biochemistry and Molecular Biology, Basic Sciences Building, New York Medical College, Valhalla, NY 10595, USA.
Abstract:
PC-SPES is an herbal mixture, with evidence of clinical efficacy against prostate cancer (CaP), recently attracting tremendous attention. Using immunoblot and cell cycle specific cDNA array analyses, we investigated effects of PC-SPES on LNCaP, a hormone-dependent prostate cancer cell line. PC-SPES inhibited expression of cyclins D and E, inhibited Rb phosphorylation, switching it to a G1-to-S inhibitory state. Moreover, cDNA array analysis showed that PC-SPES caused up-regulation of p21(WAF1/CIP1) and decreased expression of cyclin B, Nedd8, cdc2, skp1, PCNA, MAD2L1, cyclin H, CKS2, E2F, Rbx1, MCM2, MCM5, Mpp2, Cullin-Cul4A, Cks1p9 and McM7, which are involved in cell cycle progression. Taken together, our results provide a mechanistic explanation for antiproliferative and antitumor effects of PC-SPES, suggesting that induction of CDK inhibitors and downregulation of cyclins leads to dephosphorylation of Rb and growth arrest.
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