Figure 2.

Rapamycin enhances the direct CRT-induced cytotoxicity in clonogenic assays. E6/E7/Ras MOEs allowed to establish for 24 hours were treated with rapamycin at the indicated concentrations for an additional 24 hours. Cells were then dosed with cisplatin and radiation with rapamycin treatment continued concurrently. After 1 week, colonies were fixed, stained, and counted. Representative images of the colonies formed at each rapamycin concentration with equal cisplatin and radiation dosing in all conditions are shown in A. Average colony number at each concentration is shown in B, and average colony size is shown in C. Rapamycin was seen to enhance the direct CRT-induced cytotoxicity to this model HPV+ HNSCC cell line, with fewer (*P < .03, ** P < .01) and smaller (*P < .03, **P < .03) colonies forming in the presence of rapamycin.