S4 Video -

(A, B), transition from lesions/neoplasms to sheet growth. Another structural model from EGFR+ patient 4843 of what we referred to as a “transition zone”, with proSPC-presenting AT2-like cells, presumed to be neoplasms, directly adjacent to sheet-like growth of enlarged CK7-overexpressing cells (Fig 4). Cells in sheets like these take on a “dripping” or “melting wax” appearance suggestive of shedding cells with size dysregulation. The enlarged cells show loss of AT2-like differentiation in their proSPC staining. Presumptive neoplasms have both sparse proSPC puncta, unlike AT2 cells, and also negligible CK7 staining. In this way we delineated neoplasms simply by the property that they can never pass curation as models using methods we used for either normal AT2 cells, or for tumor cells. A., Cell bodies shown in rainbow, with proSPC staining introduced in the green channel during the last half of the video to illustrate the full transition of the pathology from more AT2-like neoplasms to presentation of proSPC only at the joints of large shedding cells. Note that regions of the tumor cell model possess proSPC process-like staining, but no evidence of neoplasms from which they are connected to neighbors, suggesting the process-like staining at cell junctions between tumor cells is a connection between tumor cells. B., cell bodies shown in white translucent, and nuclei shown in rainbow, with abundant stromal controls in white stone. Flybys show long fiber structures and elongated stromal nuclei of unknown type that we commonly observed in LA (yellow circle, with long pause) proSPC (green), CK7 (red). (ZIP)