PRKAA2 Promotes Tumor Growth and Inhibits Ferroptosis through SLC7A11/GSH/GPX4 Pathway in Non-Small Cell Lung Cancer

Abstract

Non-small cell lung cancer (NSCLC) is the most pervasive sort of lung cancer with deadly outcome. According to recent studies, a number of neoplastic disorders and ferroptosis are intimately connected. This study aims to identify the role of key ferroptosis-related gene (protein kinase AMP-activated catalytic subunit alpha 2, PRKAA2) and explore new directions for the diagnosis and treatment of NSCLC. The PRKAA2 expression and its influence on survival were analyzed in multiple public databases (TCGA, TIMER2.0, and GEPIA). And PRKAA2 mRNA level in NSCLC cells were examined by qRT-PCR. Silencing of PRKAA2 (sh-PRKAA2) were used to cell transfection. CCK-8, EdU, and flow cytometry assays were used to measure cell proliferation and apoptosis. The protein levels of ferroptosis markers (SLC7A11, GPX4, and NRF2) were determined by western blotting. Meanwhile, the related ferroptosis analysis, such as malondialdehyde (MDA) and glutathione (GSH), reactive oxygen species (ROS), iron, and Fe²⁺ levels were also detected in the transfected cells. Moreover, the relationship between PRKAA2 expression and SLC7A11 was analyzed. NSCLC xenograft mouse models were used for in vivo verification of the PRKAA2 function. Here, our data revealed that PRKAA2 was upregulated in NSCLC cells. Additionally, PRKAA2 strengthened cell proliferation and attenuated apoptosis and ferroptosis of NSCLC cells. The depletion of PRKAA2 enhanced the erastin-induced inhibition effect on cell growth, and notably increased the levels of MDA, ROS, iron, and Fe²⁺, while decreased GSH level in NSCLC cells. In the mechanism exploration, we discovered that PRKAA2 could activate the SLC7A11/GSH/GPx4 antioxidant pathway. The rescue experiments showed that SLC7A11 abrogated the inhibitive impacts of PRKAA2 repression on cellular proliferation, cell apoptosis, and ferroptosis in NSCLC. Besides, animal experiments proved that PRKAA2 enhanced NSCLC tumor growth in vivo. The results discovered that PRKAA2 accelerated the malignant progression, diminished apoptosis and ferroptosis in NSCLC through SLC7A11/GSH/GPX4 pathway. This study provide a novel target in the application of PRKAA2 for NSCLC treatment.

Keywords: NSCLC; PRKAA2; SLC7A11; ferroptosis.