Aspirin-Induced Chemoprevention and Response Kinetics Are Enhanced by PIK3CA Mutations in Colorectal Cancer Cells

作者:Zumwalt Timothy J; Wodarz Dominik; Komarova Natalia L; Toden Shusuke; Turner Jacob; Cardenas Jacob; Burn John; Chan Andrew T; Boland C Richard; Goel Ajay*
来源:Cancer Prevention Research, 2017, 10(3): 208-218.
DOI:10.1158/1940-6207.CAPR-16-0175

摘要

This study was designed to determine how aspirin influences the growth kinetics and characteristics of cultured colorectal cancer cells that harbor a variety of different mutational backgrounds, including PIK3CA-and KRAS-activating mutations, and the presence or absence of microsatellite instability. Colorectal cancer cell lines (HCT116, HCT116 + Chr3/5, RKO, SW480, HCT15, CACO2, HT29, and SW48) were treated with pharmacologically relevant doses of aspirin (0.5-10 mmol/L) and evaluated for proliferation and cell-cycle distribution. These parameters were fitted to a mathematical model to quantify the effects and understand the mechanism(s) by which aspirin modifies growth in colorectal cancer cells. We also evaluated the effects of aspirin on key G0-G1 cell-cycle genes that are regulated by the PI3K-Akt pathway. Aspirin decelerated growth rates and disrupted cell-cycle dynamics more profound-ly in faster growing colorectal cancer cell lines, which tended to be PIK3CA mutants. Additionally, microarray analysis of 151 colorectal cancer cell lines identified important cell-cycle regulatory genes that are downstream targets of PIK3 and were also dysregulated by aspirin treatment (PCNA and RB1). Our study demonstrated what clinical trials have only speculated, that PIK3CA-mutant colorectal cancers are more sensitive to aspirin. Aspirin inhibited cell growth in all colorectal cancer cell lines regardless of mutational background, but the effects were exacerbated in cells with PIK3CA mutations. Mathematical modeling combined with bench science revealed that cells with PIK3CA-mutations experience significant G0-G1 arrest and explains why patients with PIK3CA mutant colorectal cancers may benefit from aspirin use after diagnosis.