Extended Data Fig. 3: Microenvironmental dynamics within intracranial SCLC tumors.
From: Neuronal activity-dependent mechanisms of small cell lung cancer pathogenesis
a, Representative neurofilament (top) and Ki67 (bottom) immunohistochemistry of two human samples of SCLC brain metastasis in regions within (red box, zoomed in on right panel) and outside (yellow box, zoomed in on middle panel) 100 µm distance from neurofilament. Scale bar on left = 100 µm; scale bar on middle and right = 50 µm. b, Comparison of local nuclear density as a measure of proliferative history in human SCLC brain metastases for n = 9 patients. Regions are grouped by distance to axons immunostained for neurofilament (less than or greater than 100 µm, p = 0.0044). c, Representative immunofluorescent images of murine SCLC brain allografts (GFP, green) with neurons labeled with MAP2 (red) and NeuN (white). Scale bar = 50 µm (left), 20 µm (right). d, Representative images of proliferation rate (Ki67, red) of murine SCLC allografts (GFP, green) assessed in regions deprived of (left) or enriched for (right) neurons. Scale bar = 50 µm. e, Quantification of data in d, illustrating increased proliferation in neuron-rich compared to neuron-poor areas (n = 6 animals, p < 0.0001). Analysis with two-tailed paired t-test for b, e. ****P < 0.0001, ***P < 0.001, **P < 0.01, *P < 0.05.
