Long non-coding RNA polymorphisms and prediction of response to chemotherapy based on irinotecan in patients with metastatic colorectal cancer.

BACKGROUND

Colorectal cancer is the fourth cause of cancer related death. Drug resistance and toxicity remain major clinical issues. HOTAIR and MALAT1 are long non-coding RNAS that affect cellular proliferation, apoptosis and drug resistance; their up-regulation has been linked with a poor prognosis.

OBJECTIVE

Investigation of the association between rs4759314 HOTAIR and rs3200401 MALAT1 polymorphisms and irinotecan-based chemotherapy in terms of drug efficacy and toxicity.

METHODS

Samples from 98 patients receiving different regimens of irinotecan-based therapy were included. Efficacy and toxicity were evaluated. KRAS mutation, rs3200401 HOTAIR and rs4759314 MALAT1 polymorphisms genotyping in the tumors and peripheral blood respectively were performed with PCR.

RESULTS

Neither rs3200401 MALAT1 nor rs4759314 HOTAIR polymorphism are associated with response to treatment regimens. Rs4759314 was also not associated with increased toxicity in patients receiving irinotecan-based regimens. CT genotype of rs3200401 was associated with significantly reduced overall survival. An association between KRAS mutation and AG/GG genotypes in the rs4759314 was detected.

CONCLUSIONS

CT genotype of rs3200401 MALAT1 polymorphism could serve as a toxicity biomarker. Carriers of the G allele of the rs4759314 HOTAIR are more likely to be carriers of KRAS mutations too. However, further studies in larger patient populations are required.