According to the current knowledge, CSCs are the key factor in tumour initiation and development, metastasis, and recurrence.16 CSCs and normal stem cells share similar signalling pathways and transcription factors, including NANOG and SOX2.17 These proteins have been found overexpressed in cells of variety of precancerous and cancerous lesions, exhibiting an important function during carcinogenesis. This evidence concerns the gene SOX2 and neoplasm.