Impact of Tumor LINE-1 Methylation Level and Neoadjuvant Treatment and Its Association with Colorectal Cancer Survival.

Abstract

Recent studies suggest that long-interspersed nucleotide element-1 (LINE-1) hypomethylation is commonly found in colorectal cancer (CRC), and is associated with worse prognosis. However, the utility of LINE-1 methylation on the prognosis of CRC is still controversial, and may be due to the fact that some clinical and pathological features may affect LINE-1 methylation. Thus, the aim of this study was to assess the prognostic value of tumor LINE-1 methylation in CRC, through their association with the CRC clinical and pathological characteristics. Survival of sixty-seven CRC patients was evaluated according to the median of tumor LINE-1 methylation, as well as pathological and oncological variables. We also studied the association between LINE-1 methylation and pathological features, and finally, we assessed the overall and disease-free survival of LINE1 methylation, stratified by neoadjuvant treatment and further checked by multivariate Cox regression to assess the statistical interactions. LINE-1 was hypomethylated in the CRC tumor with respect to the tumor adjacent-free area (p