FIGURE 5 from Activation of Kras<sup>G12D</sup> in Subset of Alveolar Type II Cells Enhances Cellular Plasticity in Lung Adenocarcinoma

Notch inhibition or Sox2 upregulation suppresses tumor sphere formation in 3D culture. A, Representative fluorescent microscopy images of cultures (n = 3) showing spheres formed in Matrigel at day 14 from lineage-labeled TdTomato+ type II cells obtained by FACS sorting from Sftpc-CreER; Rosa-Tdtm and Sftpc-CreER; LSL-Kras^G12D; Rosa-TdTomato mice. Sorting was carried out after 4 weeks of one dose of tamoxifen. B, Quantitative image analysis of A showing colony forming efficiency of lineage-labeled cells calculated by ImageJ software. Error bars represent the mean ± SEM values, and significance is defined as *, P ≤ 0.05; **, P ≤ 0.01; and ***, P ≤ 0.001.