Osteopontin (SPP1) is an important component of the ECM in bone, and high expression and secretion of osteopontin in numerous cancer types — including breast, prostate, lung, gastrointestinal, hepatocellular, cervical, and bladder cancers — have been clinically correlated with poor prognosis and shortened survival times (64–73). This evidence concerns the gene SPP1 and urinary bladder cancer.