ABSTRACT: Asporin, a small leucine-rich proteoglycan encoded by the ASPN gene, is a vital player in cancer biology. Its oncogenic role in gastric cancer (GC) has been well-documented, particularly in promoting proliferation, apoptosis resistance, and migration/invasion. Nevertheless, ASPN's function in regulating glycolysis and stemness in GC cells remains underexplored. Here, we initially analyzed published transcriptomic datasets, confirming overexpression of ASPN in GC tissues compared with noncancerous stomach tissues. Furthermore, results from bioinformatics demonstrated that differentially expressed genes (DEGs) linked to ASPN expression regulate epithelial-mesenchymal transition (EMT) and stemness-related pathways. Notably, ASPN expression predicted poor patient survival. Using ASPN-deficient HGC27 and GCIY GC cell lines, which express high ASPN levels, we conducted comprehensive cell biology assays. ASPN knockdown significantly impaired GC cell viability, reduced their migratory and invasive capacities, and increased apoptosis. We also observed that ASPN deficiency disrupted glycolysis and diminished the stemness of GC cells, reflected in reduced colony and sphere formation capacity and lower expression of stemness markers. Functionally, HIF1α overexpression partially rescued the deficits from ASPN loss, positioning HIF1α as a key downstream effector. To validate our in vitro findings, we employed a xenograft GC mouse model. Consistent with our in vitro data, ASPN-deficient GC cells displayed reduced tumor growth and stemness in vivo. In conclusion, our data suggest that ASPN is oncogenic in GC, enhancing proliferation, migration, invasion, glycolysis, and stemness while inhibiting apoptosis. These findings define a crucial oncogenic function of ASPN and underscore the therapeutic potential of targeting the ASPN-HIF1α axis in GC.
