PERK mediates resistance to BRAF inhibition in melanoma with impaired PTEN

Targeting mutant BRaf in patients with melanomas harboring this oncogene has been highly successful as a first-line treatment, but other mutations may affect its efficacy and alter the route of acquired resistance resulting in recurrence and poor prognosis. As an evolving strategy, melanoma treatment needs to be expanded to include targets based on newly discovered emerging molecules and pathways. We here show that PERK plays a critical role in BRaf inhibitor-acquired resistance in melanoma with impaired PTEN. Inhibition of PERK by either shRNA or a pharmacological inhibitor blocked the growth of BRaf inhibitor-resistant melanoma with impaired PTEN in vitro and in vivo, suggesting an effective approach against melanomas with mutant BRaf and PTEN deficiency. Our current findings, along with our previous discovery that the AXL/Akt axis mediates resistance to BRaf inhibition in melanoma with wild-type PTEN, provide new insights toward a strategy for combating BRaf inhibition-acquired resistance in BRaf mutant melanoma with different PTEN statuses.