Role of stem cells in oral cancer

Stem cells are undifferentiated cells that have the ability to perpetuate themselves through self-renewal, repairing of damaged tissue and to generate mature cells of a particular tissue through differentiation. In humans, there are broadly two types of stem cells embryonic stem cells, which are derived from the inner cell mass of the blastocyst, are omnipotent and maintain their telomerase length thus capable of unlimited self-renewal. The second one is adult stem cells which are tissue specific have less capacity for self-renewal and ability to maintain their telomeres is limited and not sufficient to prevent their senescence therefore are at high risk of malignant transformation. Because over expression of telomerase activity in normal mesenchymal stem cells is correlated with accumulation of mutations.4,5