Figure 2.

Phenotypic analysis of lung cancer cell lines harboring HER2 alterations and their afatinib‐resistant sublines. A, Western blot analysis showed that the Calu3‐ARH cells exhibited downregulation of E‐cadherin and upregulation of N‐cadherin and vimentin, while the H1781‐ARS and H1781‐ARH cells exhibited upregulation of ALDH1. B, The images of the cells show that the Calu3‐ARH cells exhibited a spindle‐like shape. The H1781‐ARS and H1781‐ARH cells were non‐adhesive and capable of forming sphere‐like clusters. C, mRNA expressions of the putative cancer stem cell markers ALDHA1,ABCB1 and CD44 were examined by quantitative reverse‐ transcription PCR. ALDH1A1 was overexpressed in the H1781‐ARS and H1781‐ARH cells, while ABCB1 was overexpressed in the H2170‐ARS and H2170‐ARH cells