Galectin-1 promotes the proliferation and metastasis of lung adenocarcinoma by activating the AKT/mTOR signaling pathway

LU Huihao; HUANG Chuhong; CHENG Zhen; DONG Jiali; CHEN Yuting; LI Shujun; SU Wenmei; YANG Zhixiong

doi:10.20227/j.cnki.2096-3610.2025.05.006

Abstract：Objective This study aimed to investigate the function and mechanism of Galectin-1(Gal-1)in lung adenocarcinoma.Methods ⑴Database information analysis:The relationship between Gal-1 expression level and patient prognosis was analyzed using the TCGA-LUAD database.⑵ In vitro cell experiments:①Lung adenocarcinoma cells A549 and H1299 were transfected with siRNA and divided into two groups:the Negative control(NC)group and the experimental group(siLGALS1-1,siLGALS1-2).The effects of Gal-1 on the proliferation of lung adenocarcinoma cells were explored using cell counting kit-8(CCK-8)proliferation assay and the colony formation assay.②The effects of Gal-1 on the migration and invasion of lung adenocarcinoma cells were explored using Transwell migration and invasion assays and a wound healing assay.⑶Molecular mechanism experiments:The downstream molecular mechanisms of Gal-1 were explored through enrichment pathway analysis and rescue experiments.⑷In vivo animal experiments:Lung adenocarcinoma cells from the NC group and the stable low-expression LGALS1 group were injected subcutaneously into 4-week-old female BALB/c nude mice,with 5 mice in each group,for a total of 10 mice.The in vivo biological function of Gal-1 in the lung adenocarcinoma model was verified by constructing a subcutaneous tumor model and performing immunohistochemistry experiments.⑸Clinical sample verification:The total RNA and total protein expression levels of Gal-1 in lung adenocarcinoma tissues and adjacent tissues were detected by qRT-PCR and Western blot analyses.Results ⑴ The results of the bioinformatics analysis of the TCGA-LUAD database showed that high expression of Gal-1 mRNA was associated with poor prognosis for patients(P<0.05).⑵ In vitro experiments showed that,compared with the NC group,Gal-1 knockdown significantly suppressed the proliferative ability of lung adenocarcinoma cells(P<0.001),significantly inhibited their colony-forming ability(P<0.01),and significantly inhibited their migratory and invasive abilities(P<0.05),while Gal-1 overexpression promoted tumor cell proliferation(P<0.001)and metastasis(P<0.05).⑶ Gal-1-related differentially expressed genes were enriched in the AKT/mTOR signaling pathway.The phosphorylation levels of AKT and mTOR were increased in lung adenocarcinoma cells overexpressing Gal-1,and the use of rescue experiments demonstrated that pharmacological inhibition of mTOR effectively attenuates the oncogenic effects induced by Gal-1 overexpression(P<0.01).⑷ Compared with the NC group,the subcutaneous tumor growth rate,subcutaneous tumor volume,and weight of mice in the stable low-expression LGALS1 group were significantly reduced(P<0.05),and the Ki67 expression level as well as the phosphorylation levels of AKT and mTOR in the subcutaneous tumor tissue of mice were reduced.⑸ Clinical sample validation showed that,compared with adjacent tissues,the levels of Gal-1 RNA and protein in lung adenocarcinoma tissues were significantly increased(P<0.001).Conclusion Gal-1 acts as a critical oncogenic regulator in lung adenocarcinoma and potentially promotes tumor cell proliferation and metastasis by activating the AKT/mTOR signaling pathway.