A link between chronic inflammation and cancer has been established, but the mechanisms of carcinogenesis in inflammatory environments remain poorly understood. Here we define carcinogenesis briefly as a series of events that produce persistent, non-lethal damage followed by proliferation of the aberrant cells. Inflammation may influence this process by providing cues that allow cells to survive in the face of significant DNA damage as well as cues that foster cell proliferation. Hence, the focus of this work is to elucidate the cell signaling states associated with genotoxicity in hepatocytes under conditions of chronic inflammation by using a set of extracellular cues, both soluble and matrix-related, which can be varied systematically to create a diverse range of intracellular signaling states and phenotypic outcomes. Specifically, we hypothesize that changes in the extracellular matrix which occur during inflammation aid in promoting cell survival and proliferation in the presence of inflammatory cytokines. We further speculate that this environment could rescue apoptotic cells by upregulating inhibitors of apoptosis proteins, even after chromatin cleavage has begun, producing DNA translocations and potentiating genotoxicity. To test this hypothesis, cytokines such as TNF, TRAIL, and FasL will be used to mimic the inflammatory environment, and the effects of matrix stiffening and increases cell adhesion site densities, which occur with increased inflammation, will be mimicked using synthetic polymers and peptides. Flow cytometry will be used to assess phenotypic states by measuring activated caspases, cleaved PARP, and BrdU incorporation in addition to other markers.
Beer, N.R., Wheeler, E.K., Lee-Houghton, L., Watkins, N., Nasarabadi, S., Hebert, N., Leung, P., Arnold, D.W., Bailey, C.G., Colston, B.W. “On-Chip Single-Copy Real-Time Reverse-Transcription PCR in Isolated Picoliter Droplets.” Anal. Chem. 80(6):1854-1858 (2008).