Network 1 with 24 proteins (ACTB, AHCY, ALDH2, ANXA2, ANXA5, ATP5B, COMT, ECHS1, GSTO1, GSTP1, HNRNPC, HSP90AB1, HSPA5, HSPA8, HSPB1, HSPD1, PPA1, RPSA, RUVBL2, SNRNP200, TUBA1B, TUBB4B, UBA1, YWHAZ), network 2 with 15 proteins (ALB, ANXA3, APRT, CTSD, DST, GANAB, GSS, KRT16, EB1, MVP, NDUFS3, NME1, OPA1, PRDX3, SPECC1L), and network 3 with five proteins (ACTR3, GCC2, KRT19, NME1, SUCLA2) are associated with cancer as top disease (p < 0.022) as well as with v-myc avian myelocytomatosis viral oncogene homolog (MYC, p < 0.001) as upstream regulator. The gene discussed is CTSD; the disease is cancer.