Transcriptomic Analysis of Calcium Remodeling in Colorectal Cancer

Colorectal cancer (CRC) cells undergo the remodeling of intracellular Ca(2+) homeostasis, which contributes to cancer hallmarks such as enhanced proliferation, invasion and survival. Ca(2+) remodeling includes critical changes in store-operated Ca(2+) entry (SOCE) and Ca(2+) store content. Some changes have been investigated at the molecular level. However, since nearly 100 genes are involved in intracellular Ca(2+) transport, a comprehensive view of Ca(2+) remodeling in CRC is lacking. We have used Next Generation Sequencing (NGS) to investigate differences in expression of 77 selected gene transcripts involved in intracellular Ca(2+) transport in CRC. To this end, mRNA from normal human colonic NCM460 cells and human colon cancer HT29 cells was isolated and used as a template for transcriptomic sequencing and expression analysis using Ion Torrent technology. After data transformation and filtering, exploratory analysis revealed that both cell types were well segregated. In addition, differential gene expression using R and bioconductor packages show significant differences in expression of selected voltage-operated Ca(2+) channels and store-operated Ca(2+) entry players, transient receptor potential (TRP) channels, Ca(2+) release channels, Ca(2+) pumps, Na(+)/Ca(2+) exchanger isoforms and genes involved in mitochondrial Ca(2+) transport. These data provide the first comprehensive transcriptomic analysis of Ca(2+) remodeling in CRC.