TNF-α augments CXCL10/CXCR3 axis activity to induce Epithelial-Mesenchymal Transition in colon cancer cell

Chronic inflammation-induced metastases have long been regarded as one of the significant obstacles in treating cancer. Tumor necrosis factor-alpha (TNF-alpha), a main inflammation mediator within tumor microenvironment, affects tumor development by inducing multiple chemokines to establish a complex network. Recent reports have revealed that CXCL10/CXCR3 axis affects cancer cells invasiveness and metastases, and Epithelial-mesenchymal transition (EMT) is the main reason for frequent proliferation and distant organ metastases of colon cancer (CC) cells, However, it is unclear whether TNF-alpha- mediated chronic inflammation can synergically enhance EMT-mediated CC metastasis through promoting chemokine expression. According to this study, TNF-alpha activated the PI3K/Akt and p38 MAPK parallel signal transduction pathways, then stimulate downstream NF-KB pathway p65 into the nucleus to activate CXCL10 transcription. CXCL10 enhanced the metastases of CC-cells by triggering small GTPases such as RhoA and cdc42. Furthermore, overexpression of CXCL10 significantly enhanced tumorigenicity and mobility of CC cells in vivo. We further clarified that CXCL10 activated the PI3K/Akt pathway through CXCR3, resulting in suppression of GSK-3 beta phosphorylation and leading to upregulation of Snail expression, thereby regulating EMT in CC cells. These outcomes lay the foundation for finding new targets to inhibit CC metastases.

Automated summary

Chronic inflammation-induced metastases in cancer have been a significant obstacle in treatment. Recent studies have shown that TNF-alpha activates PI3K/Akt and p38 MAPK pathways to enhance CXCL10 transcription, promoting metastases in colon cancer cells. CXCL10, in turn, regulates EMT in colon cancer cells via the PI3K/Akt pathway, offering a new potential target for inhibiting colon cancer metastases.