Immunofluorescence of Ki-67 shows proliferation of epithelial cells showing size dysregulation.

KRAS+ patient ID’s as indicated, with behaviors shown observed in both genotypes. Green, Ki-67, red, CK7, cyan, DNA. Bottom row, a higher density scan of the sample for patient 4846 displays the structural details of unusual proliferation centers in dividing tumor cells of varying size and DNA content. Scale, 50 μm, top and middle rows, 10 μm, bottom row. Normal AT2 cells have such a small fraction of proliferating cells that they were undetectable in the objective. (PDF)