Project description:Polycyclic aromatic hydrocarbons (PAHs), such as benzo[a]pyrene (BaP), are produced by the incomplete combustion of organic matter and thus are present in tobacco smoke, charbroiled food and diesel exhaust. The nematode Caenorhabditis elegans lacks the genetic components of the classical mammalian cytochrome P450 (CYP)-mediated BaP-diol-epoxide metabolism pathway thus CYP1A1 or CYP1A2 together with human epoxide hydrolase (EPHX) was introduced into the worm genome, thereby allowing to study potential physiological, genomic and transcriptional changes after BaP exposure in these CYP-humanised C. elegans strains. Whole genome sequencing revealed a higher frequency of T>G base substitution mutations in worms expressing human CYP1A1;EPHX thereby demonstrating the amenity of introducing human genes into the C. elegans genome and their utility to serve as a model for environmental carcinogenesis and pharmacological research.
Project description:Inhibitors directed towards PARP1 and PARP2 are approved agents for the treatment of BRCA-related cancers. Other members of the PARP family have also been implicated in cancer and are being assessed as therapeutic targets in cancer and other diseases. In fact, an inhibitor of PARP7 (RBN-2397) has now reached early-stage human clinical trials. Here, we performed a genome-wide CRISPR screen for genes that modify the response of cells to RBN-2397. We identify the polycyclic aromatic hydrocarbon receptor AHR and multiple components of the cohesin complex as determinants of resistance to this agent. Activators and inhibitors of AHR modulate the cellular response to PARP7 inhibition, suggesting potential combination therapy approaches.
Project description:Cellular responses to carcinogens are typically studied in transformed cell lines, which do not reflect the physiological status of normal tissues. To address this question, we have characterized the transcriptional program and cellular responses of normal human lung WI-38 fibroblasts upon exposure to the ultimate carcinogen benzo[a]pyrene diol epoxide (BPDE). Exposure to BPDE induces a strong inflammatory response in WI-38 primary fibroblasts. Whole-genome microarray analysis shows induction of several genes related to the production of inflammatory factors, including those that encode interleukins (ILs), growth factors, and enzymes related to prostaglandin synthesis and signaling. This is the first demonstration that a strong inflammatory response is triggered in primary fibroblasts in response to a reactive diol epoxide derived from a polycyclic aromatic hydrocarbon.