Anti-cancer drugs usually work by inducing apoptosis. Unfortunately a significant body of evidence suggests that apoptosis may not be a good way to kill cancer cells? e.g. apoptosis causes rapid, caspase-dependent tumor repopulation of drug-resistant cells because apoptotic cells send growth promoting signals to neighboring cells that aren't killed and apoptosis causes non-immunogenic tumor cell killing thus reducing the likelihood of generating an effective anti-tumor immune response. Recent work from our lab suggests that it is feasible to regulate and change the mode of action of an apoptotic stimulus so that instead of killing by apoptosis, the cell dies by necroptosis. Necroptosis is a form of programmed necrosis, which does not involve caspases and is more immunogenic than apoptosis that may, therefore, be a better way to kill cancer cells. In this pilot grant we will test the central hypothesis that it is possible to manipulate a normal cell process, autophagy, in order to change the mode of action of anti-cancer drugs so that they kill human tumor cells by necroptosis instead of or as well as apoptosis. This work builds on previous studies from our group and is intended to develop pilot data establishing feasibility of our proposed approach. If we establish the feasibility of our central hypothesis, we should have a foundation to develop a larger project to test if it is possible and worthwhile to try to manipulate not only whether or not we kill cancer cells but also control how we kill them. To achieve these goals we have two aims. Aim 1. Test if the autophagy machinery regulates necroptosis in human cancer cells. Aim 2. Test if re-activation of necroptosis capacity in human tumor cells with RIPK3 silencing allows broadening of the autophagy regulation of necroptosis to more cancer cells. Upon completing this small pilot grant, we will be positioned to develop a larger project to test if we can change the current paradigm of cancer therapy to control the mechanism of tumor cell death as a way to improve cancer therapy.

R03CA229316

2018-08-01

2020-07-31