Both HPV positive and HPV negative cervical cancers are associated with cell cycle disruption; however, the contribution of the individual oncogenic drivers in cervical cancer is elusive. Therefore, utilization of informative cell lines with or without the HPV genome, can provide insights on these mechanisms. The goal of the current study was to characterize the metabolomic profiles of four distinct cervical cell lines and identify biochemical similarities and differences, reflecting specific pathways of carcinogenesis.
A normal cervical (HCK1T) and three cervical cancer cell lines, one HPV negative (C33A), and two HPV positive (SiHa HPV16+) and HeLa HPV18+) were used. Metabolites were detected utilizing a Waters ACQUITY ultra-performance liquid chromatography (UPLC) and a Thermo Scientific Q-Exactive high resolution-accurate mass spectrometer interfaced with a heated electrospray ionization (HESI-II) source and Orbitrap mass analyzer operated at 35,000 mass resolution. Welch’s two-sample t-test was used to identify biochemicals that differed significantly
The dataset documented a total of 462 biochemicals, 439 known compounds and 23 of unknown structural identity. An altered carbohydrate metabolism was documented in the two HPV-positive cell lines exhibiting features of the Warburg metabolism. This is consistent with the role of HPV E6 in promoting Warburg metabolism, by stabilizing expression of the glycolytic mediator HIF-1. SiHa and HeLa cells exhibited purine salvage pathway activity, while C33A cells uniquely showed accumulation of cytidine, through a novel mechanism. SiHa and C33A cells exhibited similar profiles in the Cysteine/Glutathione pathway. Analysis of lipid levels revealed distinct metabolic profiles among the four cell lines. To identify other associated changes independent from cervical cancer-derived transformed cells, we sorted the dataset by significance of changes of normal HCK1T cells, relative to other cells. This revealed a large number of changes, with striking increases in dipeptide levels. This may represent a unique pathway to provide alternate sources to increase fuel growth. Finally, several of the 23 identified unnamed biochemicals, exhibited discrete profiles in each of the four cell lines, suggesting cell-line specific utilization.
The metabolomic profiling of normal, HPV positive and HPV negative cervical cancer cells provides novel mechanistic insights into cervical carcinogenesis. Collectively, the data reflect highly dynamic differences among the cellular groups that will help elucidate both unique and common aspects of perturbed growth profiles of cervical cancer.