- The candidate tumor suppressor gene BLU, located at the commonly deleted region 3p21.3, is an E2F-regulated, stress-responsive gene and inactivated by both epigenetic and genetic mechanisms in nasopharyngeal carcinoma. Qiu, G.H., Tan, L.K., Loh, K.S., Lim, C.Y., Srivastava, G., Tsai, S.T., Tsao, S.W., Tao, Q. Oncogene (2004)