Disruption in cholesterol homeostasis by free fatty acid promote colon cancer by modulating CCL20

Background: Colorectal cancer (CRC) displays metabolically flexible but dysregulated lipid homeostasis, involving increased lipid synthesis, altered fatty acid uptake, enhanced storage, and remodeling of membranes and cholesterol pools. These processes interact with inflammatory signaling networks and may support cancer progression. CCL20, a chemokine elevated in lipid-rich and inflammatory CRC microenvironments, has been implicated in tumor progression, but its relationship with lipid metabolic regulation remains unclear. This study examines possible interactions between lipid metabolism and CCL20 signaling, and specifically its effects on lipid accumulation, membrane biophysics, and cholesterol metabolic programs in CRC models. Methods: CRC cell lines (Caco2, DLD1, HCT116) were exposed to free fatty acids (FFAs) differing in chain length (C12, C16) and saturation (C16:0, C18:1(9)). CCL20 production was quantified by ELISA. FFA uptake was assessed using Lauric acid (C12) and palmitic acid (C16). Lipid accumulation was assessed by BODIPY mean fluorescence intensity normalized to cell size. Membrane fluidity was measured using Laurdan generalized polarization (GP) and fluorescence imaging. Total, cellular and secreted cholesterol, as well as ratio of esterified and free cholesterol ratios were measured alongside expression of cholesterol-associated enzymes, including HMGCR, SOAT2, and SREBP2. CCL20-overexpressing HCT116 cells were included to validate effects of CCL20. Results: Data indicate that FFAs of differing lengths may variably modulate CCL20 expression. Distinct patterns of FFA internalization and accumulation, and membrane fluidity shifts were observed in CRC cell line with differential CCL20 signaling. Levels of cholesterol and expression of key metabolic enzymes were found to be associated with CCL20 modulation. Conclusions: These findings establish a clear link between lipid metabolism and CCL20 expression and function in CRC cells. Ongoing studies aim to validate these observations and develop a unified model of CCL20-driven metabolic regulation in colorectal cancer.