The role of E2F targets in oncogene-induced replication stress tolerance as potential new targets for cancer therapy (360G-Wellcome-211926_Z_18_Z)

In human cells, deregulated G1/S transcription, the transcriptional wave that commits cells to the cell cycle, is at the basis of many cancers and it is governed by the transcription factor E2F2. Oncogenes such as c-myc, deregulate G1/S transcription leading to uncontrolled cellular proliferation. We will induce expression of the oncogene c-myc in epithelial human cells, that directly leads to the increase in levels of E2F transcription. Unscheduled S-phase entry leads to replication stress and DNA damage, and thus genomic instability, which may lead to cell death or drive cancer initiation if the DNA damage repair is impaired. Paradoxically, this increased E2F-dependent transcription provides also a mechanism for replication stress tolerance to protect cells from catastrophic genomic instability. Some cancers have very high levels of replication stress, and by understanding how these cells are able to tolerate such high levels, we may be able to target these buffers for new cancer therapeutics. A large scale screen is being performed in the lab to identify these targets. I will investigate the role of one of these targets. Preliminary work in the lab and previous work in yeast suggests that the Smc5/6 complex may be such a candidate for oncogene-induced tolerance.