CEACAM Gene Family: A Circuitous Journey towards Metastasis in Breast Cancer

Abstract

The ubiquitous up-regulation of CEACAM6 in colon, pancreatic, breast and lung cancer is well established. This protein is known for its invasive and metastatic properties in pancreatic adenocarcinoma as well as in breast cancer. We propose that the overexpression of CEACAM5 and CEACAM6 are a pre-requisite for invasive and metastatic behavior of breast cancer. We have conducted bioinformatics studies to compare the expression profiles of CEA gene family members in sets of RNA-seq data for MCF10A (non-tumorigenic epithelial cell line) and MCF7 (human breast cancer cell line) obtained from European Nucleotide Archives. RNA-seq data was mapped using HISAT2 followed by alignment and abundance analysis using Stringtie and visualized using ballgown package in R software environment. Specifically, we observed a 4.5-fold upregulation in CEACAM5 expression while 7-fold increase was recorded for CEACAM6 expression. We propose that the up-regulation of both these proteins in MCF7 cell line compared to MCF10A implicates their inconspicuous role in tumorigenesis, enhanced invasiveness and thus, leading to increased propensity towards breast cancer metastasis. Further studies are required in breast cancer cell lines and appropriate animal models to validate these in silico observations.