SPHK1 and neoplasm: Furthermore, a group of differential proteins including protein disulfide isomerase A6 (PDIA6), sphingosine kinase 1 (Sphk1), Anx4a, vimentin, tubulin alpha-1C chain, beta-centractin, alph-actinin-4, ras-related protein Rap-2c, and tropomyosin beta chain showed a close relationship with motility and the cytoskeleton, which may modulate the invasion and migration of tumor cells.