By using cell lines of gastric cancer, cervical cancer, and prostate cancer, we found that within the nucleus, NONO served as a co-factor essential for c-Myc transactivation in regulating expression of GALNT6 and MGAT1. Meanwhile, mRNA stability of GALNT2, GALNT6, and hnRNPU was maintained by cytoplasmic NONO, suggesting the dual NONO activity in regulating c-Myc transactivation and mRNA stabilization essential for protein glycosylation and cancer progression. This evidence concerns the gene MGAT1 and gastric cancer.