Induction of the Epithelial-to-Mesenchymal Transition of Human Colorectal Cancer by Human TNF-β (Lymphotoxin) and its Reversal by Resveratrol

Abstract

Objective: Tumor necrosis factor-beta (TNF-β), as an inflammatory mediator that has been shown to promote tumorigenesis, induces NF-κB. Natural multi-targeted agent resveratrol in turn shows anti-inflammatory and anti-cancer properties. Epithelial-to-mesenchymal transition (EMT) allows cancer cells to turn into a motile state with invasive capacities and is associated with metastasis and development of cancer stem cells (CSC). However, TNF-β-induced EMT and the anti-invasion mechanism of resveratrol on CRC are not yet completely understood. Methods: We investigated the underlying molecular mechanisms of resveratrol on TNF-β/TNF-βR-induced EMT and migration of CRC cells (HCT116, RKO, SW480) in monolayer or 3D alginate cultures. Results: TNF-β, similar to TNF-α, induced significant cell proliferation, morphological change, from an epithelial to a spindle-like mesenchymal shape with the formation of filopodia and lamellipodia associated with the expression of EMT parameters (elevated vimentin and slug, reduced E-cadherin), increased migration/invasion, and formation of CSC in all CRC cells. Interestingly, these effects were dramatically decreased in the presence of resveratrol or anti-TNF-βR with TNF-β co-treatment, inducing biochemical changes to the mesenchymal-epithelial transition (MET), with a planar cell surface and suppressed formation of CSC cells. This was associated with a significant increase in apoptosis. Furthermore, we found that resveratrol suppressed TNF-β-induced NF-κB and NF-κB-regulated gene biomarkers associated with growth, proliferation, and invasion. Finally, TNF-βR interacts directly with focal adhesion kinase (FAK) and NF-κB. Conclusion: These results suggest that resveratrol down-regulates TNF-β/TNF-βR-induced EMT, at least in part via specific suppression of NF-κΒ and FAK in CRC cells.

Evidence That Calebin A, a Component of Curcuma Longa Suppresses NF-κB Mediated Proliferation, Invasion and Metastasis of Human Colorectal Cancer Induced by TNF-β (Lymphotoxin)

“…Phosphorylation of the p65-NF-κB subunit by IKKs/IκBα is a major activation step in the canonical NF-κB pathway, followed by nuclear translocation and DNA binding to modulate gene transcription [61]. Moreover, our findings are also consistent with those that have shown that numerous natural substances mediate their anti-tumorigenic potential through targeting the NF-κB pathway [19,42,[62][63][64], thereby stimulating tumor cell apoptosis and suppressing proliferation and migration. Indeed, Calebin A has recently been shown to suppress the activation of the p65-NF-κB pathway in several cell types, thereby suppressing cell growth and enhancing apoptosis [27].…”

“…Indeed, previous studies have shown that Calebin A inhibits constitutive NF-κB activation as well as negatively regulating TNF-α and LPS-induced NF-κB activation [27]. We could previously show in TNF-β-stimulated CRC cells that NF-κB is a major target for the natural substance resveratrol in suppressing CRC tumor cell malignity [12,13,36,63]. Interestingly, a recent study could show that Calebin A mediates its anti-tumorogenic properties by inhibiting P300/CBP-associated factor (PCAF), which serves as transcriptional co-activator for both p53 and NF-kB [32,65].…”

Calebin A Potentiates the Effect of 5-FU and TNF-β (Lymphotoxin α) against Human Colorectal Cancer Cells: Potential Role of NF-κB

“…Interestingly, previous works have shown that the chemoresistant CRC cells expressed increased several biomarkers of CSC and of epithelial-to-mesenchymal-transition (EMT), a higher capacity to become more tumor malignity (motility, proliferation, drug resistance) and developed colonospheres. It has been demonstrated that other natural compounds like curcumin, resveratrol and/or 5-FU significantly decreased CSC-and EMT-biomarkers expression in CRC cells [16,58,59]. Importantly, it is to be expected that Calebin A as a natural anti-tumor agent has a crucial target on the cancer stem cells in the tumor cell populations.…”

Mechanisms of the Epithelial–Mesenchymal Transition and Tumor Microenvironment in Helicobacter pylori-Induced Gastric Cancer

“…During this process, epithelial cells undergo a series of biochemical changes, which lead to the loss of polarity and migratory capacity of cells, resulting in cell shape changes (cell elongation). EMT promotes the transformation of immobile epithelial cells into motile mesenchymal cells, enhancing the metastatic properties [69,70]. Further, adherens and tight junctions become impaired, resulting in a mesenchymal phenotype [12,[71][72][73].…”