We previously reported that a recombinant adenovirus, carrying a pro-apoptotic gene (PUMA) under the regulation of Ets/AP1 (RAS-responsive elements) suppressed the growth of cancer cells harboring hyperactiveKRAS.
The Raf-MEK-ERK1/2 pathway is hyper-activated in a large fraction of colorectal cancers due to mutations in K-Ras and we show that treatment of CRC cell lines with MEK inhibitors causes an increase in Cdx2 expression.
These studies establish germline KRAS mutations as a cause of human disease and infer that the constellation of developmental abnormalities seen in Noonan syndrome spectrum is, in large part, due to hyperactive Ras.