Developing\nMultiple Media Approach to Investigate\nReproducible Characteristic VOCs of Lung Cancer Cells

Cellular volatile organic compound (VOC) detection is\ncrucial for\nstudying lung cancer biomarkers. However, the reported VOC biomarkers\nfrom the same cell line seem to be inconsistent across different research\ngroups. It is possibly related to the variation in culture media,\nand the result obtained by a conventional single medium approach (SMA)\ndepends on what medium is used in the cell experiment. This study\nproposes a multiple media approach (MMA) to investigate reproducible\ncharacteristic VOCs of lung cancer cells. Using solid-phase microextraction–gas\nchromatography–mass spectrometry (SPME-GC-MS) in combination\nwith untargeted analysis, we conducted two independently repetitive\nexperiments to compare lung cancer cells (A549) and normal lung cells\n(BEAS-2B) under three culture media conditions (RPMI 1640, DMEM, and\nHam’s F12). Both experiments indicated that, compared with\n62–96 VOCs obtained by the SMA, only two VOCs (3-methyl-1-butanol\nand 2-methyl-1-butanol) were reproducibly achieved by the MMA. Moreover,\ntheir concentrations were significantly lower in lung cancer cells\nthan in normal cells. Further targeted analysis confirmed the downregulation\ntrend of both VOCs in subcutaneous and primary tumor tissues from\nthe lung cancer model mouse. The present work demonstrated that the\nMMA cell experiment, just like the multicenter trials for cell lines,\ncan facilitate the discovery of reproducible characteristic VOCs.\nThis provides a cellular experimental basis and scientific evidence\nfor lung cancer biomarker investigation and even breath biopsy technique\ndevelopment.