Expression data from GNMT knockout mice

We report that 7 of 7 female Gnmt-/- mice developed hepatocellular carcinoma (HCC), the most common form of liver cancer, at the mean age of 16.1 months. In contrast, only one-third (2/6) of male Gnmt-/- mice had HCC, the remaining had either premature death or liver necrosis. Microarray analysis showed that genes involved in the following pathways were deregulated in different stages of tumorigenesis: S-adenosylmethionine (SAM)-dependent methyltransferases, metabolism, signal transduction, cell proliferation, cell adhesion and immune responses. This study reveals that GNMT plays an important role in the prevention of hapatotumorigenesis through regulating DNA methylaiton and oxidative stress signaling pathways. We postulate that GNMT is a stress-responsive protein and its expression may account for the gender difference of the susceptibility to liver cancer. Keywords: Gnmt knockout Liver tissues from wild-type or Gnmt knockout mice at young ages, devoloping dysplasia nodules or HCC were used for RNA extraction and hybridization on Affymetrix microarrays. For 11 weeks old mice, total RNA were mixed in equal proportion from 3 mice.