ART4 and cancer: One of the most well-known oncogenes in cancer is SPP1 (secreted phosphoprotein 1, which encodes the protein Osteopontin (OPN), a non-collagenous bone matrix protein belonging to the Small Integrin-Binding Ligand N-linked Glycoprotein (SIBLING) family of glycoproteins, which plays an extensive role in several stages of tumor development [3], wherein its increased secretion has been found to be correlated with higher risks of malignancy in various forms of cancer [4].