Abstract 326P
Background
Metabolites involved in glutathione (GSH) metabolism, such as cysteine, γ-glutamylcysteine, and glutathione, are elevated in advanced clear cell renal cell carcinoma (ccRCC), correlating with poorer survival outcomes. Glutamate-cysteine ligase catalytic subunit (GCLC), a pivotal enzyme in GSH synthesis, serves as the rate-limiting step. Despite extensive research on GCLC's roles in tumor progression and metastasis across diverse cancers, its specific contribution to RCC metastasis remains inadequately investigated.
Methods
Through differential gene analysis of proteomics and transcriptomics, GO analysis, KEGG pathway analysis, TCGA database analysis, clinical sample studies, in vitro and in vivo experiments using a mouse lung metastasis model, this study comprehensively investigates the role and molecular mechanisms of glutathione metabolism pathway-related proteins in renal cancer metastasis at clinical, molecular, cellular, and animal levels.
Results
In vitro Transwell migration and in vivo tail vein transfer experiments confirmed Renca-Lu3 cells' strong lung metastatic potential. Proteomic analysis of glutathione metabolism pathways in Renca and Renca-Lu3 cells revealed significant GCLC down-regulation. TCGA database analysis further supported the association of GCLC with RCC progression and prognosis. Immunohistochemical RCC tissues showed markedly reduced GCLC expression in metastatic RCC, which correlated with patient survival. In vitro assays (MTT proliferation, transwell migration, and scratch assays) demonstrated that GCLC inhibits proliferation, migration, and invasion of renal carcinoma cells. In vivo experiments using a tail vein metastasis model confirmed GCLC suppressive effect on renal carcinoma. Western blot analysis confirmed that key apoptotic markers were influenced by GCLC variations during anoikis, with significant down-regulation of GCLC observed in renal cancer cells after anoikis treatment.
Conclusions
GCLC functions as a novel tumor suppressor gene in RCC. Inactivation of GCLC enhances resistance to anoikis, promoting RCC cell metastasis and systemic dissemination, leading to the formation of distant metastases throughout the body.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
2023 Jiangsu Province Graduate Research Innovation Plan (KYCX23_2101), National Natural Science Foundation of China (82172777).
Disclosure
All authors have declared no conflicts of interest.