ABSTRACT
Objective To investigate genes and involved biological processes closely associated with stem cell markers of colorectal cancer-epithelial cell adhesion molecule (EpCAM) + and CD44+.Methods By the bioinformatics method,with microarray data of colorectal cancer from gene expression omnibus (GEO) database and R2 platform,the genes significantly related with CD44 and EpCAM expression were screened out.The differences in expression of related genes were analyzed on the basis of gender,family history of cancer,alcohol and Dukes stage.The expression of related genes in colorectal cancer was compared with that of other tumors and healthy subjects.At same time,the pathways of the genes and Kyoto encyclopedia of genes and genomes (KEGG) of CD44 and EpCAM significantly related genes were analyzed with gene ontology (GO) and KEGG method.Single factor analysis of variance and Chi-square test of four-fold table with correction for continuity were used for statistical analysis by R2 platform embedded statistical tools.Results The expressions of CD44 and EpCAM were detected in all 315 colorectal cancer samples.A total of 888 and 6 316 genes were screened out which were significantly associated with CD44 and EpCAM expression.CD44 was positively correlated with EpCAM.There was no obvious correlation between the expression of five genes which expressed in all 315 tissues and gender family history of cancer,alcohol and Dukes stage (all P＞0.05).By further compared with the expression in other tumors and tissues,the expressions of two genes solute carrier family 12,member 2 (SLC12A2) and proteome of centriole 1 centriolar protein B (POC1B) in colorectal tumor were significantly higher than that in other tumors (F=289.422、128.456,all P＜0.01),and its expression in colorectal cancer was obviously higher than that in tissues of health subjects (F=349.519、128.456,all P＜0.01).GO analysis indicated there were 15 GO semantics related with both CD44 and EpCAM.The genes related with CD44 and EpCAM were analyzed by KEGG access pathway method,while seven and 10 pathways were found to be statistically significant (all P＜0.01).Conclusions CD44 and FpCAM commonly expressed in colorectal cancer.The genes related with CD44 and EpCAM expression are involved in multiple tumor biological processes.