When mutated, HRAS can act as an oncogene, causing normal cells to become cancerous. Somatic HRAS mutations have been associated with some cases of bladder, thyroid and kidney cancers and in nevi. Based on clinical evidence in melanoma with the related family member NRAS, downstream pathway MEK inhibitors may be a feasible treatment strategy. The effectiveness of MEK inhibitors for HRAS-mutant thyroid and bladder cancer patients has not yet been investigated.