Immunohistochemistry (IHC) assay showed that the PLCD1 expression was significantly downregulated in tumors tissue from the miR-191 agomir group and upregulated in tumors tissue from the miR-191 antagomir group, suggesting that miR-191 promotes OSCC tumor growth in vivo by regulating protein expression of PLCD1 (Fig. 6D). This evidence concerns the gene PLCD1 and neoplasm.