GRN and neoplasm: Importantly, the expression level of PGRN was significantly higher in PTC cells than that in normal thyroid follicular epithelial cells, and the highest expression level was in BCPAP cells derived from poorly differentiated [40], which indicated that the expression level of PGRN may be related to the degree of tumor differentiation, meanwhile involved in the malignant regulation of tumor, so that reflecting the malignant degree of tumor.