Induction of the intestinal stem cell signature gene SMOC-2 is required for L1-mediated colon cancer progression.
A ShvabG HaaseA Ben-ShmuelNancy S GavertT BrabletzS DedharA Ben-Ze'evPublished in: Oncogene (2015)
Overactivation of Wnt-β-catenin signaling, including β-catenin-TCF target gene expression, is a hallmark of colorectal cancer (CRC) development. We identified the immunoglobulin family of cell-adhesion receptors member L1 as a β-catenin-TCF target gene preferentially expressed at the invasive edge of human CRC tissue. L1 can confer enhanced motility and liver metastasis when expressed in CRC cells. This ability of L1-mediated metastasis is exerted by a mechanism involving ezrin and the activation of NF-κB target genes. In this study, we identified the secreted modular calcium-binding matricellular protein-2 (SMOC-2) as a gene activated by L1-ezrin-NF-κB signaling. SMOC-2 is also known as an intestinal stem cell signature gene in mice expressing Lgr5 in cells at the bottom of intestinal crypts. The induction of SMOC-2 expression in L1-expressing CRC cells was necessary for the increase in cell motility, proliferation under stress and liver metastasis conferred by L1. SMOC-2 expression induced a more mesenchymal like phenotype in CRC cells, a decrease in E-cadherin and an increase in Snail by signaling that involves integrin-linked kinase (ILK). SMOC-2 was localized at the bottom of normal human colonic crypts and at increased levels in CRC tissue with preferential expression in invasive areas of the tumor. We found an increase in Lgr5 levels in CRC cells overexpressing L1, p65 or SMOC-2, suggesting that L1-mediated CRC progression involves the acquisition of a stem cell-like phenotype, and that SMOC-2 elevation is necessary for L1-mediated induction of more aggressive/invasive CRC properties.
Keyphrases
- stem cells
- induced apoptosis
- cell cycle arrest
- gene expression
- signaling pathway
- poor prognosis
- genome wide
- oxidative stress
- endoplasmic reticulum stress
- epithelial mesenchymal transition
- endothelial cells
- copy number
- binding protein
- cell proliferation
- dna methylation
- cell death
- cell adhesion
- long non coding rna
- cystic fibrosis
- metabolic syndrome
- skeletal muscle
- staphylococcus aureus
- bone marrow
- adipose tissue
- insulin resistance
- toll like receptor
- single cell
- high fat diet induced