Subsequent RT-qPCR assays demonstrated that VAV3, CHGA, GREM1, USP2, WNT9B, and CTSH exhibited significantly lower expression levels in the four tumor cell lines than those in the HK2 cell line (P < 0.05; Figure 9B), corroborating the findings presented in Figure 9A. This evidence concerns the gene CHGA and neoplasm.