Inositol hexaphosphate inhibits growth and induces differentiation of PC-3 human prostate cancer cells.
We investigated the effects of inositol hexaphosphate (InsP6) on growth inhibition and differentiation of human prostate cancer cells PC-3 in vitro. A significant dose- and time-dependent growth inhibition was observed as tested by the MTT-incorporation assay (P < 0.05 at 1 mM InsP6 after 24 h treatment, P < 0.01 at 0.1 mM after 3 days). DNA synthesis as determined by [3H]thymidine incorporation assay was also suppressed by InsP6 in a dose-dependent manner, occurring as early as 3 h after treatment and continuing up to 48 h (P < 0.01 at 1 mM InsP6). A 9- to 10-fold increase (P < 0.01) in expression of HLA class I molecule associated with tumor immunosurveillance and cell differentiation was induced by InsP6. The marker for prostatic cell differentiation, prostate acid phosphatase, was significantly (P < 0.05) increased after 48 h treatment at 0.5-5 mM InsP6. Since InsP6 strongly inhibits growth and induces differentiation in human prostate cancer cells in vitro, in vivo studies using a tumor xenograft model and a prostate carcinogenesis model are warranted to validate the efficacy of InsP6 in the treatment and prevention of prostate cancer.
Shamsuddin
A M
AM
Department of Pathology, University of Maryland School of Medicine, Baltimore 21201, USA.
Yang
G Y
GY
D000135:Acid Phosphatase / Q000032:analysis*; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D004247:DNA / Q000096:biosynthesis; D015395:Histocompatibility Antigens Class I / Q000032:analysis; D006801:Humans; D008297:Male; D010833:Phytic Acid / Q000494:pharmacology* / Q000627:therapeutic use; D011471:Prostatic Neoplasms / Q000188:drug therapy / Q000473:pathology* / Q000517:prevention & control; D014407:Tumor Cells, Cultured
D015395:Histocompatibility Antigens Class I; D010833:Phytic Acid; D004247:DNA; D000135:Acid Phosphatase