Altered membrane amino acids composition in human colorectal cancer tissue

Abstract

AbstractCancer transformation is characterized by changes in cell metabolism, which can alter the structure and function of cell membrane components, including integral membrane proteins. Qualitative and quantitative estimations of integral membrane protein are necessary for studies aimed at understanding their modifications under pathological conditions. Herein, we used a high-performance liquid chromatography (HPLC)-based approach that involved selective hydrolysis of isolated tissue cell membrane proteins to peptides, resolution by chromatography and determination of the amino acid content (phenylalanine (Phe), tyrosine (Tyr), cysteine (Cys) and lysine (Lys)) in individual peptides. The results demonstrate decrease in peptide levels and their amino acids content in integral membrane proteins in human colorectal cancer tissue. Therefore, cancer transformation causes a decrease in the levels of integral membrane proteins, which may in turn lead to an increase in the levels of other charged molecules on the cell surface, such as phospholipids. It might lead to the reconstruction and functional rearrangement of the cell membrane, for example: the permeability, electric properties, fluidity etc.