Further investigation showed that the PGK2 protein abundance quantified by FragPipe is highly correlated with the PGK1 protein abundance (Fig. 4d), whereas the PGK2 mRNA abundance does not correlate with PGK1 mRNA abundance in the same tumor cohort, and all tumors had very low PGK2 mRNA abundance, including more than half with no PGK2 mRNA detection (Fig. 4e). Here, PGK1 is linked to neoplasm.