Two ELP variants, that is, Tat-A1E28 (A1 represent one-unit AP1and E28 represent repeat of [(VPGVG)5(VPGFG)2-(VPGVG)3(VPGGG)3 (VPGAG)]2) and Tat-A4V48 (V48 indicates 48 pentapeptide repeat of VPGVG) were used as tumor specific delivery system. The gene discussed is TAT; the disease is neoplasm.