To determine whether Itga1 expression is required for attachment on Col1, we depleted Itga1 in mesenchymal lung cancer cells (393P_ZEB1, 344SQ, and H1299) and found that Itga1 deficiency led to reduced attachment to Col1 and cell spreading on Col1-coated wells (Figure 2, A–C, and Supplemental Figure 2, A–F). This evidence concerns the gene ITGA1 and lung cancer.