Poster Presentation HUPO 2019 - 18th Human Proteome Organization World Congress

Global proteomic and phosphoproteomic profiling to identify proteins and pathways that regulate cell survival in hypoxic conditions (#489)

Keshava K. Datta 1 , Rebekah Ziegman 1 , Harsha Gowda 1 2 3
  1. QIMR Berghofer Medical Research Institute, Herston, QLD, Australia
  2. Faculty of Medicine, University of Queensland, Brisbane, QLD, Australia
  3. School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, QLD, Australia

Hypoxia is a common feature in various solid tumors. Cancer cells in hypoxic environments are resistant to both chemotherapy and radiation. Hypoxia is also associated with immune suppression. Identification of proteins and pathways that regulate survival of cancer cells in hypoxic environments can reveal potential vulnerabilities that can be exploited to improve efficacy of anti-cancer therapy. Gene expression profiling studies have identified several hypoxia-induced genes. This includes well-known transcription factor hypoxia-inducible factor 1-alpha (HIF-1α). We carried out global proteome profiling and phosphoproteome profiling in melanoma cell lines to identify proteins and pathways that are induced by hypoxia. We used Q Exactive HF-X Hybrid Quadrupole-Orbitrap Mass Spectrometer for analysis and employed label free quantitation (LFQ) for global proteomic and phosphoproteomic comparison. As expected, several proteins that are known targets of hypoxia inducible factors (HIFs) were found to be overexpressed in the hypoxic models. In addition, several metabolic enzymes showed altered expression revealing metabolic reprogramming in hypoxic conditions. We also carried out global proteomic profiling of cells grown at different concentrations of oxygen. These studies revealed potential oxygen sensors that showed oxygen concentration dependent protein expression pattern. Phosphoproteomic profiling revealed kinase mediated signaling pathways that are induced in hypoxic conditions. Our data provides a comprehensive view of proteomic alterations in hypoxic conditions and reveals potential mechanisms that regulate cell survival in hypoxic environments. These mechanisms can be targeted to improve therapeutic outcomes in cancer treatment.