First Author | Ahmad R | Year | 2017 |
Journal | Oncogene | Volume | 36 |
Issue | 47 | Pages | 6592-6604 |
PubMed ID | 28783170 | Mgi Jnum | J:252671 |
Mgi Id | MGI:6101011 | Doi | 10.1038/onc.2017.259 |
Citation | Ahmad R, et al. (2017) Loss of claudin-3 expression induces IL6/gp130/Stat3 signaling to promote colon cancer malignancy by hyperactivating Wnt/beta-catenin signaling. Oncogene 36(47):6592-6604 |
abstractText | The hyperactivated Wnt/beta-catenin signaling acts as a switch to induce epithelial to mesenchymal transition and promote colorectal cancer. However, due to its essential role in gut homeostasis, therapeutic targeting of this pathway has proven challenging. Additionally, IL-6/Stat-3 signaling, activated by microbial translocation through the dysregulated mucosal barrier in colon adenomas, facilitates the adenoma to adenocarcinomas transition. However, inter-dependence between these signaling pathways and key mucosal barrier components in regulating colon tumorigenesis and cancer progression remains unclear. In current study, we have discovered, using a comprehensive investigative regimen, a novel and tissue-specific role of claudin-3, a tight junction integral protein, in inhibiting colon cancer progression by serving as the common rheostat of Stat-3 and Wnt-signaling activation. Loss of claudin-3 also predicted poor patient survival. These findings however contrasted an upregulated claudin-3 expression in other cancer types and implicated role of the epigenetic regulation. Claudin-3-/- mice revealed dedifferentiated and leaky colonic epithelium, and developed invasive adenocarcinoma when subjected to colon cancer. Wnt-signaling hyperactivation, albeit in GSK-3beta independent manner, differentiated colon cancer in claudin-3-/- mice versus WT-mice. Claudin-3 loss also upregulated the gp130/IL6/Stat3 signaling in colonic epithelium potentially assisted by infiltrating immune components. Genetic and pharmacological studies confirmed that claudin-3 loss induces Wnt/beta-catenin activation, which is further exacerbated by Stat-3-activation and help promote colon cancer. Overall, these novel findings identify claudin-3 as a therapeutic target for inhibiting overactivation of Wnt-signaling to prevent CRC malignancy. |