PTEN and nasopharyngeal carcinoma: A recent study suggested that miR-222 was up-regulated in nasopharyngeal carcinoma (NPC) tissues and malignant cell lines compared with adjacent normal samples and cell lines; moreover, miR-222 up-regulation significantly increased cell growth and conferred radioresistance by targeting phosphatase and tensin homolog (PTEN) in NPC cells [15].