Increased N-glycosylation of PSMA by GnT-V enhances tumor malignancy through interacting with JAK2 and the subsequent STAT3-mediated transcriptional activation in prostate cancer.

Prostate-specific membrane antigen (PSMA), a membrane glycoprotein with high specificity, has emerged as an effective target for imaging and therapy in prostate cancer. Despite its potential, the role and molecular mechanism underlying PSMA glycosylation and overexpression remain to be fully clarified. In this study, we performed a comprehensive analysis of site-specific N-glycosylation patterns of PSMA, revealing that β1,6-GlcNAc branching at N121 and N336, catalyzed by GnT-V, is crucial for its expression. We found that the degradation of non-N-glycosylated PSMA predominantly occurs through the autophagy-lysosome pathway. Notably, androgen deprivation was shown to upregulate the expression of PSMA and GnT-V, simultaneously activating the transcription factor STAT3. Co-immunoprecipitation assay confirmed a direct interaction between PSMA and JAK2, which facilitates the activation of STAT3. This, in turn, drives the overexpression of PSMA and promotes its aberrant N-glycosylation, thereby advancing prostate cancer progression. Importantly, combined inhibition of STAT3 and N-glycosylation demonstrated a synergistic effect in reducing tumor viability. Our findings elucidate a novel positive feedback loop involving JAK2/STAT3/GnT-V/PSMA axis, contributing to the malignancy of prostate cancer and providing a foundation for innovative therapeutic strategies targeting this pathway.