GSK3 inhibition circumvents and overcomes acquired lorlatinib resistance in ALK-rearranged non-small-cell lung cancer

Anaplastic lymphoma kinase (ALK) fusion is found in ~3%–5% of patients with non-small-cell lung cancers (NSCLCs). Although the third-generation ALK tyrosine kinase inhibitor (TKI) lorlatinib shows high clinical efficacy in ALK-positive NSCLC, most of the patients eventually relapse with acquired resistance. Recently, drug-tolerant persister (DTP) cells have been considered an important seed of acquired resistance cells. In this study, we established lorlatinib intermediate resistant cells from a patient-derived cell model. Glycogen synthase kinase 3 (GSK3) inhibitions significantly suppressed lorlatinib intermediate resistant cell growth. GSK3 inhibition also sensitized acquired resistance cells derived from alectinib-treated patients with or without secondary mutations to lorlatinib. Therefore, GSK3 plays a crucial role in developing acquired resistance against lorlatinib in ALK-positive NSCLC mediated by lorlatinib intermediate resistant cells and could be a potential molecular target to prevent acquired lorlatinib resistance and overcome ALK-TKI resistance.