ErbB380Â kDa, a nuclear variant of the ErbB3 receptor, binds to the Cyclin D1 promoter to activate cell proliferation but is negatively controlled by p14ARF

► We characterize here ErbB380kDa, a nuclear variant of the ErbB3 receptor. ► This variant is devoid of the extracellular domain of the receptor. ► Nuclear ErbB380kDa binds the Cyclin D1 promoter and up-regulates proliferation. ► The tumor suppressor p14ARF negatively regulates this nuclear pathway. ► Nuclear ErbB3 could counteract cancer therapies targeting the EGF-R cytoplasmic pathways.