The Escherichia coli protein toxin cytotoxic necrotizing factor 1 induces epithelial mesenchymal transition

Area of Science:

• Microbiology
• Molecular Biology
• Cancer Research

Background:

• Toxigenic bacteria produce protein toxins with carcinogenic signatures.
• Few toxins have been proven to promote cancer induction or progression.
• Epithelial to mesenchymal transition (EMT) is critical for tumor malignancy.

Purpose of the Study:

• To investigate the effect of cytotoxic necrotising factor 1 (CNF1) on intestinal epithelial cells.
• To elucidate the molecular mechanisms by which CNF1 influences cell behavior.
• To determine the role of the microenvironment in CNF1-mediated carcinogenic traits.

Main Methods:

• Exposure of intestinal epithelial cells to CNF1.
• Analysis of EMT markers including ZEB1, Snail1, E-cadherin, and β-catenin.
• Assessment of mTOR pathway activation, wound healing, and invasion assays.
• Investigation of CNF1 effects in the presence of inflammatory factors.

Main Results:

• CNF1 induces EMT in intestinal epithelial cells.
• CNF1 up-regulates ZEB1 and Snail1, delocalizes E-cadherin and β-catenin, and activates mTOR.
• CNF1 promotes accelerated wound healing and invasion.
• Nontransformed epithelial cells require inflammatory factors alongside CNF1 to exhibit mesenchymal traits.

Conclusions:

• CNF1 promotes carcinogenic traits in intestinal epithelial cells by inducing EMT.
• The cellular microenvironment and cell type significantly influence CNF1's ability to promote cancer.
• CNF1's role in cancer progression is context-dependent, requiring specific conditions for full carcinogenic potential.