SPP1 and neoplasm: Many other genes in the MRS model, such as PFN2, HAVCR1, CDCA8, CYP26B1, TTK, SPP1, STC2, and CBX2 play vital roles in regulating and participating in the progression of different cancers, thereby affecting tumor cell proliferation, migration, and invasion and epithelial–mesenchymal transition (45–52).