Overexpression of a dominant negative Ras-specific GEF protein has been reported to phenotypically revert several phenotypes in K-ras transformed murine fibroblasts, including Ras-GTP level, morphology, anchorage independent growth, reduction of Ras-dependent tumor formation in nude mice, glucose dependence and mitochondrial dysfunction [15]–[17]. The gene discussed is KRAS; the disease is neoplasm.