 Furthermore, it explains why lung cancer and other solid tumors are completely refractory to treatments based on these compounds that are effective therapies for some types of leukemia.The role of BRG1 in sensitivity or resistance to anti-cancer drugs had been recently highlighted by the elucidation of the mechanisms of action of darinaparsin, an arsenic-based anti-cancer drugs.Darinaparsin has been shown to induce phosphorylation of BRG1, which leads to its exclusion from chromatin.