Effects of Green Tea and EGCG on IL‐8 Inflammatory Responses in LPS and TNF‐α‐Induced, Differentiated HT‐29 Human Colon Cancer Cells

Abstract

Colon cancer incidence has been linked to inflammation and lifestyle factors, including diet. Green tea (GT) and epigallocatechin‐3‐gallate (EGCG), the main flavonoid component of GT, have been reported to have anti‐inflammatory and cancer preventive effects in numerous model systems. Populations that consume GT have been found to have a reduced risk of colon cancer incidence, which is the reason for exploring the anti‐inflammatory effects of GT in this study. The purpose of this research was to determine the effects of GT or EGCG on inflammation in a human colon cancer (HT‐29) cell line. Aqueous GT and EGCG extracts were prepared and matched for total phenol content by the Folin‐Ciocalteu method. Cell viability was determined by the MTT assay. Differentiation was induced by sodium butyrate and confirmed by the alkaline phosphatase assay. Inflammation was induced in the HT‐29 cells by LPS 0127:B8 (1 ng/ml) and TNF‐α(100 pg/ml). Interleukin 8 (IL‐8) concentration was measured by ELISA. Results of the IL‐8 ELISA indicate that increasing levels of GT (0.005, 0.01 and 0.05 mg/ml) and EGCG (0.005, 0.01 and 0.05 mg/ml) cause a dose dependent decreases in IL‐8 concentrations after co‐treatment with LPS and TNF‐α. GT and EGCG demonstrated anti‐inflammatory effects in this cell line, suggesting potential benefits relative to human colon cancer.This project was supported by the people of the state of North Carolina.Grant Funding Source: North Carolina State Appropriations