PCK2通过SLC38A2介导的谷氨酰胺摄取促进非小细胞肺癌细胞恶性表型OA

To investigate the molecular mechanism by which phosphoenolpyruvate carboxykinase 2(PCK2)regulates glutamine transport under low-glucose conditions and its impact on the malignant behaviors of non-small cell lung cancer(NSCLC)cells.Methods:Stable PCK2 knockdown(KD group)and negative control(NC group)cell lines(n=3 for all experiments)were established in the human NSCLC A549 cell line..The impact of PCK2 on the transcription and protein expression of solute carrier family 38 member 2(SLC38A2)were assessed using PRM proteomics,Western blotting,and dual-luciferase reporter assays.Cell proliferation(MTT),migration(wound healing),and apoptosis(flow cytometry)were analyzed via MTT assay,scratch wound healing assay,and flow cytometry,respectively under low-glucose conditions(1000 mg/L).Functional rescue experiments were performed by establishing a Gln supplementation group(KD+Gln group)and an SLC38A2 overexpression group(KD+SLC38A2 group).Results:Upon PCK2 knockdown,SLC38A2 promoter activity decreased by approximately 60％(P＜0.000 1)and its protein expression was significantly reduced(P＜0.01).Under low-glucose conditions,cell proliferation was inhibited in the KD group.The 24-hour migration rate(≈ 20％)was significantly lower than that in the NC group(≈ 55％,P＜0.000 1),while the apoptosis rate(≈ 13％)was significantly higher(NC group≈ 4.5％,P＜0.0001).Both glutamine supplementation and SLC38A2 overexpression significantly reversed these phenomena,restoring migration rates to approximately 50％(P＜0.01 vs.KD)and reducing apoptosis to about 5.5％(P＜0.0001 vs.KD).Conclusion:Under low-glucose stress,PCK2 maintains Gln uptake by regulating SLC38A2 expression at the transcriptional level,thereby promoting the proliferation,migration,and survival of NSCLC cells.