CD90 combined with radiation on Colony forming efficiency in ESCC. Colony forming efficiency was used to detect the radiosensitivity of treated ESCC cells. The results showed that CD90 overexpressing cells have a stronger self-renewal ability (A,B), radiation inhibits the growth of tumor cells, however, CD90 overexpression can partly reverse these effects (C,D). Moreover, the SF data were fitted into the single-hit multi-target model formula. *, P<0.05.