[Can Analysis of Cellular Lipidome Contribute to Discrimination of Tumour and Non-tumour Colon Cells?]

Colon cancer development is often characterized by abnormalities in lipid synthesis and metabolism, which may influence energetic balance, structure and function of biological membranes, or production of specific mediators and cell signalling. The changes in lipid profile and metabolism (lipidome) may significantly affect cell behaviour and response to therapy. Permanent epithelial cell lines at various stages of cancer development are used for better understanding of this topic on cellular and molecular levels. In our study, we hypothesized that detailed analyses of colon cancer cell line lipidomes may help to identify major alterations in the amount and profile of specific lipid classes/species, which can contribute to their different response to various stimuli.

Cellular lipids were isolated from six human epithelial cell lines derived from tissues at various stages of tumour development. Liquid chromatography coupled with tandem mass spectometry analyses were performed in order to determine amount and mass profiles of all phospholipid (PL), lysophospholipid (lysoPL) and sphingolipid classes. The data was statistically evaluated (cluster and discrimination analyses) with respect to mutual comparison of cell lines and to significantly discriminating lipid types.

The results of cluster analysis arranged cell lines in order corresponding to their level of transformation (normal cells, adenoma, carcinoma and lymph node metastasis). The results of discrimination analyses revealed the most discriminating lipid types and distinction in PL: lysoPL ratios. Particularly, significant correlation of the amount and profiles of both specific lysoPL and sphingolipid classes with cell transformation level were observed. Similar approaches are now applied to compare lipidomes of colon epithelial cells isolated from tumour vs. non-tumour samples of colon cancer patients.

Our results indicate that a) selected cancer cell lines are suitable model for lipidomic studies that can serve as a basis for subsequent clinical research, b) cellular lipidome analyses may help to discriminate tumour and non-tumour cells in clinical samples, where specific types of lipids could serve as biomarkers.Key words: colon cancer - cell lines - liquid chromatography - mass spektrometry - phospholipids - sphingolipids - bioinformatics The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. This work was supported by Czech Health Research Council, grant No. AZV 15-30585A.Submitted: 19. 3. 2018Accepted: 18. 4. 2018.