AP-1 transcription factor network explains diverse patterns of cellular plasticity in melanoma
SummaryCellular plasticity associated with fluctuations in transcriptional programs allows individual cells in a tumor to adopt heterogeneous differentiation states and switch phenotype during their adaptive responses to therapies. Despite increasing knowledge of such transcriptional programs, the molecular basis of cellular plasticity remains poorly understood. Here, we combine multiplexed transcriptional and protein measurements at population and single-cell levels with multivariate statistical modeling to show that the state of AP-1 transcription factor network plays a unifying role in explaining cellular plasticity in melanoma. We find that a tightly regulated balance between AP-1 factors cJUN, FRA2, FRA1 and cFOS determines the intrinsic diversity of differentiation states and adaptive responses to MAPK inhibitors in individual melanoma cells. Perturbing this balance through genetic depletion of specific AP-1 proteins, or by MAPK inhibitors, shifts cellular heterogeneity in a predictable fashion. Thus, AP-1 may serve as a critical node for manipulating cellular plasticity with potential therapeutic implications.