In situ probing changes in fatty-acyl chain length and desaturation of lipids in cancerous areas using mass spectrometry imaging.

Abstract

Aberrant changes in the expression levels and structure of lipids may shape tumor microenvironment. In this study, we have performed mass spectrometry imaging and profiling analysis of 63 tissues of five types of cancer, namely, breast, colorectal, esophageal, lung, and gastric cancer, using in situ liquid extraction electrosonic spray ionization mass spectrometry imaging. Alteration of fatty-acyl chain length of unsaturated phosphatidylcholines, phosphatidylinositols, and phosphatidylserines and of chain length of (un)saturated fatty acids are associated with different cancerous areas of five types of cancer. The ratios of the same fatty-acyl carbon atom lipids with one double bond difference and the ratios of the same chain-length fatty acids with one double bond difference exhibited significant differences among the cancerous areas of five types of cancer. Our data may reveal that there were different lipid metabolism networks among five types of cancer.