Periostin – an unexplored tumor marker of oral squamous cell carcinoma

Cancer is a multi-hit multi-step process that ultimately leads to malignant transformation. Genes encoding for extracellular matrix, proteins of epidermal development, and cell adhesion molecules are mostly altered in oral squamous cell carcinoma. Of late, the paradigm for diagnosis has shifted from clinical status to molecular one. This is because molecular changes occur immediately, whereas clinical changes take a long time to show up. Hence, by evaluating various markers of cancer, its progression, severity, resistance, and prognosis can be predicted way before the clinical signs occur. These markers are present either in the tumors or hosts and help to distinguish between normal and dysplastic tissue. They generally increase during the disease progression or relapse, and decrease when the disease goes into remission. They can also be detected in blood, plasma and saliva apart from tissues. Periostin is one such molecule that gets altered, and hence can be used as a marker. Studies on the expression of periostin in oral cancer are very few; therefore, an attempt is made to throw some light on this novel protein and its role in oral cancer. It can be used in target therapy solely or as an adjunct in treating oral squamous cell carcinoma.