Investigation of the significance and role of androgen receptor expression in basal/squamous type urothelial carcinoma cell line J82 cells

Urothelial carcinoma is a prevalent malignancy that exhibits a distinct sex disparity, with a higher incidence in males. Among the various molecular subtypes, the basal/squamous subtype is associated with poor prognosis and therapeutic resistance. Androgen receptor (AR) signaling has been implicated in the pathogenesis of urothelial carcinoma; however, its precise role remains unclear, particularly in basal/squamous-type urothelial carcinoma. The present study sought to ascertain the functional role of AR in Ba/Sq-type UC by employing J82 cells, a prominent cell line representing this subtype. J82 cells stably expressing the AR (J82-FLAG-AR) were established via retroviral transduction. Gene and protein expression analyses were conducted using quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting, respectively, following dihydrotestosterone (DHT) treatment. A series of experiments were conducted to investigate the interaction between the androgen receptor (AR) and enhancer of zeste homolog 2 (EZH2), as well as their impact on cell proliferation and p21 expression. The results indicated that AR expression in J82 cells led to a decrease in the expression of epithelial markers (CLDN1, CLDN4) and an increase in the expression of the luminal marker GATA3 and cyclin-dependent kinase inhibitor p21. DHT treatment suppressed the proliferation of J82-FLAG-AR cells, accompanied by the upregulation of p21. Co-immunoprecipitation demonstrated the interaction of AR with EZH2, and combined treatment with DHT and the EZH2 inhibitor GSK126 further elevated p21 expression. However, this combination did not enhance the antiproliferative effect beyond that of DHT alone. AR expression in basal/squamous-type urothelial carcinoma cells promotes p21-mediated growth inhibition while simultaneously reducing epithelial markers, suggesting a dual role in suppressing proliferation and potentially promoting epithelial-mesenchymal transition. These findings contribute to our understanding of AR's complex role of AR in UC, and provide insights into potential therapeutic strategies targeting AR.