Figure 4.KRAS insertion mutants promoted in vivo growth of NIH3T3 cells. In vivo tumorgenic assay in nude mice showed that tumors formed in the sites implanted with NIH3T3 cells expressing KRAS mutants (G12V, ¹⁰G¹¹, or ¹¹GA¹²) were consistently larger than that implanted with wild-type KRAS (WT) and empty vector (EV) controls. By western blotting, the expression of KRAS protein in the NIH3T3 transfectants and tumors dissected from the xenografts (T1–T5) was detected.