RAC1 and psoriasis: In thyroid cancer, overexpression of Cdc42 increases production of lactic acid and polarization of M2 macrophages, which function to inhibit T cells and allow cancer cells to proliferate uninhibited.230 Cdc42 is also thought to have an essential role in the regulation of epileptic seizures, as pretreatment with ML141, a Cdc42 inhibitor, was found to reduce seizure severity.231 Finally, in the skin, constitutively active Rac1 (RACV12) in mice resulted in the development of lesions similar to human psoriasis and inhibition prevented psoriasis hyperplasia in xenografts.