Proinflammatory Cytokines IL-6 and TNF-α Increased Telomerase Activity through NF-κB/STAT1/STAT3 Activation, and Withaferin A Inhibited the Signaling in Colorectal Cancer Cells. (6th June 2017)

• Record Type: Journal Article
• Authors: Chung, Seyung S.; Wu, Yong; Okobi, Quincy; Adekoya, Debbie; Atefi, Mohammad; Clarke, Orette; Dutta, Pranabananda; Vadgama, Jaydutt V.
• Other Names: Tsuji Fumio Academic Editor.
• Is Part Of: Mediators of inflammation. Volume 2017(2017)
• Publication Date: 2017-06-06
• Subjects: Inflammation -- Mediators -- Periodicals; Biological response modifiers -- Periodicals; Inflammation (Pathologie) -- Médiateurs; Immunomodulateurs; Biological response modifiers; Inflammation -- Mediators; Immunology; Autacoids; Immunologic Factors; Cell Adhesion Molecules; Cell Communication; Cytokines; Inflammation; Periodicals; Electronic journals; 616.0473
• DOI: 10.1155/2017/5958429
• Languages: English
• ISSNs: 0962-9351

Abstract

Abstract : There are increasing evidences of proinflammatory cytokine involvement in cancer development. Here, we found that two cytokines, IL-6 and TNF- α, activated colorectal cancer cells to be more invasive and stem-like. Combined treatment of IL-6 and TNF- α phosphorylated transcription factors STAT3 in a synergistic manner. STAT3, STAT1, and NF- κ B physically interacted upon the cytokine stimulation. STAT3 was bound to the promoter region of human telomerase reverse transcriptase (hTERT). IL-6 and TNF- α stimulation further enhanced STAT3 binding affinity. Stem cell marker Oct-4 was upregulated in colorectal cancer cells upon IL-6 and TNF- α stimulation. Withaferin A, an anti-inflammatory steroidal lactone, inhibited the IL-6- and TNF- α -induced cancer cell invasion and decreased colonosphere formation. Notably, withaferin A inhibited STAT3 phosphorylation and abolished the STAT3, STAT1, and NF- κ B interactions. Oct-4 expression was also downregulated by withaferin A inhibition. The binding of STAT3 to the hTERT promoter region and telomerase activity showed reduction with withaferin A treatments. Proinflammatory cytokine-induced cancer cell invasiveness is mediated by a STAT3-regulated mechanism in colorectal cancer cells. Our data suggest that withaferin A could be a promising anticancer agent that effectively inhibits the progression of colorectal cancer.