Sox2 is necessary for androgen ablation-induced neuroendocrine differentiation from Pten null Sca-1(+) prostate luminal cells

Prostate adenocarcinoma undergoes neuroendocrine differentiation to acquire resistance toward anti-hormonal therapies. The underlying mechanisms have been investigated extensively, among which Sox2 has been shown to play a critical role. However, genetic evidence in mouse models for prostate cancer to support the crucial role of Sox2 is missing. The adult mouse prostate luminal cells contain both castration-resistant Sox2-expressing Sca-1(+) cells and castration-responsive Sca-1(−) cells. We show that both types of the luminal cell are susceptible to oncogenic transformation induced by loss of function of the tumor suppressor Pten. The tumors derived from the Sca-1(+) cells are predisposed to castration resistance and castration-induced neuroendocrine differentiation. Genetic ablation of Sox2 suppresses neuroendocrine differentiation but does not impact the castration resistant property. This study provides direct genetic evidence that Sox2 is necessary for androgen ablation-induced neuroendocrine differentiation of Pten null prostate adenocarcinoma, corroborates that the lineage status of the prostate cancer cells is a determinant for its propensity to exhibit lineage plasticity, and supports that the intrinsic features of cell-of-origin for prostate cancers can dictate their clinical behaviors.