Huntingtin Over-Expression Does Not Alter Overall Survival in Murine Cancer Models

A reduced incidence of various forms of cancer has been reported in Huntingtons disease (HD) patients and may be due to pro-apoptotic effects of mutant huntingtin. We tested this hypothesis by assessing the effects of huntingtin protein over-expression on survival in two murine cancer models. We generated yeast artificial chromosome (YAC) HD mice containing human huntingtin transgenes with various CAG tract lengths (YAC18, YAC72, YAC128) on either an Msh2 or p53 null background, which have increased cancer incidence. In both mouse models of cancer, the over-expression of either mutant or wild-type huntingtin had no significant effect on overall survival. These results do not support the hypothesis that mutant huntingtin expression is protective against cancer.