Moreover, the protein levels of immunohistochemistry (IHC) staining obtained from the Human Protein Atlas (HPA) database showed that the expression of four of the hub genes (CRYAB, FAM189A2, ANGPTL1 and PPP1R12B) were significantly lower in tumour tissues than in normal tissues (Fig. 15), which was consistent with that at the transcriptional level. This evidence concerns the gene PPP1R12B and neoplasm.