Chemoresistance, Radioresistance, and Androgen Deprivation Therapy Resistance in Prostate Cancer

One of the primary obstacles encountered in the clinical care of individuals suffering from advanced, life-threatening prostate cancer is the development of resistance to therapeutic interventions, including androgen deprivation therapy (ADT), chemotherapy, and radiation. To overcome this resistance, it is essential to possess a comprehensive comprehension of the underlying processes that drive the tumor microenvironment. This knowledge should extend beyond the androgen receptor (AR)-signaling pathway and include other factors that contribute to treatment resistance. By doing so, novel pharmacological targets may be identified. The tumor microenvironment facilitates crucial signaling pathways that enhance the survival and invasive capabilities of cancer cells by conferring resistance to apoptosis. Specifically, the phenomenon known as epithelial-mesenchymal transition (EMT), which is regulated by transforming growth factor-β (TGF-β), grants stem cell characteristics and facilitates the development of a migratory and invasive phenotype by enabling resistance to anoikis. The potential effectiveness of the main drug DZ-50 in treating advanced metastatic castration-resistant prostate cancer (mCRPC) lies in its ability to induce a therapeutic response driven by anoikis. The capacity for differentiated prostate tumor gland epithelium to undergo cellular de-differentiation into mesenchymal cells via EMT and subsequent re-differentiation through mesenchymal-epithelial transition (MET) has a remarkable role in the evolution of cancers. One notable attribute of the EMT landscape is the downregulation of E-cadherin, resulting in the disruption of adherent junctions. This event effectively evades apoptosis, triggered by detachment from the extracellular matrix, hence facilitating the metastatic potential and resistance to chemotherapy. Researchers are now investigating the potential linkages between AR and TGF-β signaling in order to develop more effective therapeutic approaches for the treatment of mCRPC. This chapter aims to explain the existing data about therapeutic resistance in individuals suffering from recurrent prostate cancer that is resistant to standard treatments.