Consistent with the finding that knocking down wild-type HRAS or NRAS can reduce tumor growth of some KRAS mutation-positive cancer cells [23], knocking down wild-type KRAS also reduced tumor growth over time (Fig 1C), resulting in a statistically significant 91% reduction in tumor weight at endpoint compared to scramble shRNA control cells (Fig 1D and 1E). This evidence concerns the gene HRAS and cancer.