TNF-alpha Induces Pro-Inflammatory Factors in Colorectal Cancer Microenvironment

Objective: The tumor microenvironment has a crucial role in organizing cancer malignancy, progression, drug resistance and survival. It consists of cellular and non-cellular components. These non-cellular components such as cytokines, extracellular matrix, growth factors and metabolites are responsible for shifting the action from pro-cancer to anti-cancer effects. Twenty percent of all cancers occur in association with chronic inflammation via cytokines. Even cancers that are not caused by chronic inflammation, present high levels of cytokine expression pattern in their tumor microenvironment. Tumor necrosis factor-alpha (TNF-α) and some interleukins are characterized as pro-tumorigenic cytokines and they were involved in cancer by presenting their ability to activate the oncogenic transcription factors. The aim of this study is to evaluate the remodeling of colorectal cancer tumor microenvironment by TNF-α. Material and Methods: TNF-α (5ng/ml) was applied to HT-29 colorectal cancer cells, then human soluble factors were determined by using Human Cytokine Group 1, 8 plex Panel (Bio-Rad Laboratories Inc. USA) and Magpix Luminex instrument and xPONENT software (version 4.2, Luminex Corp, Austin, Texas, US). The results were normalized to total protein concentration estimated via Bradford assay. Results: Current research highlights the effect of TNF-α on the tumor microenvironment. Interleukin-6 and interleukin -8 soluble factors were higher in TNF-α treated colorectal cancer cells when compared with untreated control group. Conclusion: The results of the study show that TNF-α is responsible for elevating the levels of interleukin-6 and interleukin-8, which are associated with inflammation in the tumor microenvironment. Key words: Colorectal Cancer, Tumor Microenvironment, Cytokines, TNF-α, Interleukin-6, interleukin -8