Be Easy and Chill: Melanoma Cells Tell Lymph Node Fibroblasts to Relax.

Melanomas coopt tumor-draining lymph nodes to support metastatic potential and install immunosuppression. The specific mechanisms that mediate lymph node education, however, remain incompletely understood. In this issue, Rovera and colleagues describe the deactivation of contractile lymph node fibroblasts by dedifferentiated melanoma cells, leading to lymph node expansion and enhanced melanoma invasive potential. Fibroblastic reticular cell relaxation depended upon inhibition of constitutive JAK1/STAT3 and YAP/TAZ signaling, which was mediated in part by tumor secretion of the inflammatory cytokine, IL1. These data support an emerging hypothesis that intrinsic melanoma heterogeneity feeds forward to drive microenvironmental adaptations that mediate invasion and progression. See related article by Rovera et al., p. 1774.