PT - JOURNAL ARTICLE AU - Agarwal, Banke AU - Bhendwal, Sanjay AU - Halmos, Balasz AU - Moss, Steven F. AU - Ramey, William G. AU - Holt, Peter R. TI - Lovastatin Augments Apoptosis Induced by Chemotherapeutic Agents in Colon Cancer Cells DP - 1999 Aug 01 TA - Clinical Cancer Research PG - 2223--2229 VI - 5 IP - 8 4099 - http://clincancerres.aacrjournals.org/content/5/8/2223.short 4100 - http://clincancerres.aacrjournals.org/content/5/8/2223.full SO - Clin Cancer Res1999 Aug 01; 5 AB - β-Hydroxy-β-methylglutaryl coA reductase inhibitors (HRIs) inhibit isoprenylation of several members of the Ras superfamily of proteins and therefore have important cellular effects, including the reduction of proliferation and increasing apoptosis. Significant toxicity at high doses has precluded the use of HRIs as a monotherapy for cancers. We therefore studied whether combinations of the HRI lovastatin with standard chemotherapeutic agents would augment apoptosis in colon cancer cells. In the colon cancer cell lines SW480, HCT116, LoVo, and HT29, lovastatin induced apoptosis with differing sensitivity. Pretreatment with lovastatin significantly increased apoptosis induced by 5-fluorouracil (5-FU) or cisplatin in all four cell lines. Lovastatin treatment resulted in decreased expression of the anti-apoptotic protein bcl-2 and increased the expression of the proapoptotic protein bax. The addition of geranylgeranylpyrophospate (10 μm) prevented lovastatin-induced augmentation of 5-FU and cisplatin-induced apoptosis; mevalonate (100 μm) was partially effective, whereas cotreatment with farnesyl pyrophosphate (100 μm) had no effect. These data imply that lovastatin acts by inhibiting geranylgeranylation and not farnesylation of target protein(s). Our data suggest that lovastatin may potentially be combined with 5-FU or cisplatin as chemotherapy for colon cancers.