Augmenter of liver regeneration gene expression in human colon cancer cell lines and clinical tissue samples

Augmenter of liver regeneration (ALR) is an hepatotrophic factor responsible for the increased regenerative capacity of mammalian liver and ALR gene expression has been well-documented in liver cirrhosis and hepatocellular carcinoma tissue samples. The present study aimed to quantify and evaluate ALR gene expression in human colon cancer cell lines and tissue samples.

Total RNA was isolated from 6 colorectal cancer cell lines and 23 primary colorectal tumors, cDNA was prepared and ALR mRNA expression analysis was performed using quantitative real-time PCR.

ALR mRNA expression was confirmed in all 6 colorectal cancer cell lines (SW480, SW620, DLD-1, RKO, COLO-205 and HTC-116) and an epithelial one (WISH). DLD-1 cell line showed the highest ALR mRNA levels, followed by RKO, COLO-205, HCT-116, SW480, SW620 and WISH cell lines. ALR gene expression levels were detected in all cancer tissue samples (N=23), being significantly increased in well/moderately compared to poorly differentiated tumors (p=0.0208). ALR gene expression levels were increased in Dukes' stage A/B compared to stage C tumors, at a non significant level (p=0.2842). ALR mRNA levels were slightly higher in colon cancer tissues compared to adjacent non-neoplastic ones (N=19), at a non significant level (p=0.2122).

The present study verified for the first time the ALR gene expression in both human colon cancer cell lines and clinical samples. Enhanced ALR gene expression was negatively correlated with advanced histopathological grade and stage in both colon cancer cell lines and human tissue samples, implicating ALR participation at the early stage of colon malignant progression.