Extended Data Fig. 7: The combined inhibition of XPO1, MEK, and PI3K inhibits cell growth to the same degree as KRAS inhibition. The combined inhibition of KRAS, AKT, and SRC has the highest antitumor activity; DLC1 expression makes a critical contribution to this antitumor activity.
a Photomicrographs of colonies quantified in Fig. 7a. Scale bar = 2 mm. Anchorage-independent colonies growth in responses to treatment with the KRAS inhibitor sotorasib alone or in the combination of the indicated drugs treatment. The combined inhibition of XPO1, PI3K, and MEK have similar colonies growth inhibition as KRAS inhibition. The combined inhibition of KRAS, AKT, and SRC had greater colonies growth inhibition compared to KRAS inhibition alone. b Xenograft tumors after 3 weeks of treatment with the indicated inhibitors quantified in Fig. 7b. c Quantitation of agar colonies (>0.4 mm) after the indicated drugs treatment. Bar graphs represent mean value and error bars represent SD. N = 3 independent experiments. p = 0.0004 for control versus KRAS-G12Ci, p = 0.0022 for control versus MEKi+PI3Ki, p = 0.0112 for KRAS-G12Ci versus MEKi+PI3Ki, and p = 0.0146 for KRAS-G12Ci versus KRAS-G12Ci+AKTi+SRCi. d Excised xenograft tumors after treatment with the indicated inhibitors. In the NCI-H23 xenograft tumors, combined inhibition of KRAS, AKT, and SRC has the highest antitumor activity in DLC1 expressed tumors. Most of the antitumor activity was attributable to DLC1 protein expression, as the isogenic DLC1-KO line was much less susceptible to the three-drug combination. e,f Quantitation (e) of agar colonies (>0.4 mm) after the indicated drugs treatment, as photomicrographs of colonies shown (f). In figure E, bar graphs represent mean value and error bars represent SD. N = 3 independent experiments. p = 0.0071 for MEKi+PI3Ki versus KRAS-G12Ci and p = 0.0069 for KRAS-G12Ci versus KRAS-G12Ci+AKTi+SRCi. In Figure F, hotomicrographs of anchorage-independent colonies growth in responses to treatment with KRAS inhibitor sotorasib and with the indicated inhibitors in NCI-H23 parental line and isogenic DLC1-KO line. Scale bar = 2 mm. For the statistical analysis for Figures C and E, parametric unpaired one tailed t-test with Welch’s correction was performed using Prism software, and no adjustments were made for multiple comparisons.
