Fig. 6: Effects of DSP gene disruption in melanoma and keratinocyte monocultures and cocultures.
From: Desmosome mutations impact the tumor microenvironment to promote melanoma proliferation
a, Keratinocytes were engineered to stably express either NTC shRNA or DSP shRNA constructs; melanoma cells were not genetically engineered. These cell types were grown and characterized independently or as cocultures (first three plates). Alternatively, melanoma cells were characterized in keratinocyte-conditioned medium (final plate). Cells were stained using specific antibodies and characterized using proliferation assays. b, 5-Ethynyl-2′-deoxyuridine (EdU) assay of melanoma cell proliferation (A375), shown for keratinocyte and melanocyte cocultures in which keratinocytes stably expressed NTC shRNA (dark gray) versus DSP shRNA (light gray) for 2, 4, 6 or 8 days. Each violin plot summarizes five distinct fields per well × three biological replicates for n = 15 replicate measurements. Significance was determined using a two-sided, two-sample t-test, Bonferroni-corrected for multiple testing (****P < 6 × 10−5). c, CyQUANT assay of melanoma cell proliferation when grown in conditioned medium from keratinocytes stably expressing either NTC shRNA (dark gray) or DSP shRNA (light gray). Results for three different melanoma cell lines are shown (A375, metastatic; WM1862 and WM1552C, nonmetastatic). Each violin plot summarizes six conditioned-medium measurements. Significance was determined using a two-sided, two-sample t-test, Bonferroni-corrected for multiple testing (*P = 0.020, **P = 0.009, ****P = 1.08 × 10−8). d, Suggested model in which desmosome mutations in keratinocytes lead to decoupling of keratinocyte-melanoma cells and decreased keratinocyte adhesion, which in turn promotes melanocyte proliferation.
