CXCR4, a potential predictive marker for docetaxel sensitivity in gastric cancer.

UNLABELLED The aim of this study was to explore predictive genes involved in docetaxel sensitivity of gastric cancer. MATERIALS AND METHODS Microarray analysis was performed to explore various gene expression levels between parental and docetaxel-resistant cells. A panel of 11 genes selected according to microarray analysis were validated and tested further in 11 cancer cell lines, resulting in 4 genes, CXCR4, CDK6, USP15 and CDH1. Histoculture drug response assay (HDRA) was used to examine docetaxel sensitivity, while qRT-PCR was used to measure the mRNA levels of the genes in 25 surgically dissected gastric cancer specimens. RESULTS Only CXCR4 mRNA levels in gastric cancer tissues were correlated with docetaxel sensitivity (R(2)=0.23, p=0.019) and significantly higher in resistant specimens (p=0.038). AMD3100, a CXCR4 antagonist, enhanced the docetaxel cytotoxicity in vitro. CONCLUSION CXCR4 mRNA expression levels may be a potential predictive biomarker in gastric cancer.