Abundance, fatty acid composition and saturation index of neutral lipids are significantly different between isogenic primary and metastatic colon cancer cell lines

Abstract

Lipid droplets, the dynamic organelles that store triglycerides (TG) and cholesterol esters (CE), are highly accumulated in colon cancer cells. This work studies the TG and CE subspecies profile in colon carcinoma cells lines, SW480 derived from primary tumor, and SW620 derived from a metastasis of the same tumor. It was previously reported that the total TG and CE content is dramatically higher in SW620 cells; however, TG and CE subspecies profile has not been investigated in detail. The presented work confirms that total TG and CE content is significantly higher in SW620 cells. Moreover, the FA-composition of TGs is significantly altered in SW620 cells, with significant decrease in the abundance of saturated triglycerides. This resulted in significantly decreased TG saturation index in SW620 cells. The saturation index of CEs was also significantly decreased in SW620 cells. The saturation indices of some other major lipid classes were either similar or only moderately different between SW480 and SW620 cells. We also compared the expression of metabolic genes that may regulate these changes in the lipidomic profiles.