Abstract
Currently, the mechanisms of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) resistance have been a focus of clinical research. Despite that most of the mechanisms of acquired EGFR TKI resistance have been revealed, about 30% of non-small-cell lung cancer (NSCLC) cases have not been fully elucidated, especially for lung adenocarcinoma (LUAD). Recently, LPCAT1, an important enzyme of phospholipid metabolism, has been found to bridge the gap between the oncogene and metabolic reprogramming. In NSCLC, LPCAT1 has been shown to participate in progression and metastasis. However, little is known about the role of LPCAT1 in acquired EGFR TKI resistance. In this study, elevated LPCAT1 expressions were observed in an EGFR TKI-resistant cell line (PC-9R) relative to a corresponding EGFR TKI-sensitive cell line (PC-9). In vivo and in vitro gene functional studies showed that LPCAT1 contributed to the pathogenesis of gefitinib resistance in LUAD, where an LPCAT1-EGFR positive feedback loop formed and then regulated its downstream signaling molecules of the EGFR/PI3K/AKT signaling pathway. The results provided novel insights into the acquired resistance mechanism of EGFR TKI from the perspective of phospholipid metabolism. These findings suggest LPCAT1 may serve as a potential therapeutic target for patients with EGFR TKI-resistant NSCLC.