pattern in NEPC in contrast to CRPC, indicating the epigenetic nature of neuroen­docrine differentiation (NED). Furthermore, it was shown that the suppressed genes in NEPC mouse models had a higher concentration of PRC2 target genes and were linked to unfavorable outcomes [41]. This implies that the overexpression of EZH2 has a functional importance in this context. The N-Myc-downregulated genes in the MYCN-driven NEPC models have a notable enrichment of epigenetic targets asso­ciated with EZH2/PRC2 [45, 46]. Based on the acquired evidence, N-Myc interacts with SUZ12 polycomb repressive complex 2 subunit (SUZ12) and EZH2, altering the activity pathway of PRC2 to suppress androgen receptor signaling and thereby contributing to the emergence of NED.It is worth noting that an increase in the expression of EZH2 has been found in tumors that originate from prostate basal cells with overexpression of N-Myc and myrAKT1 [6, 47]. Moreover, the upregula- tion of EZH2 in NEPC tumors was conrmed in a more extensive collection of patient tumors and in organoids obtained from needle biopsies of metastatic lesions originating from end-stage prostate cancer patients [48, 49]. The endeavor to com­prehend the molecular functioning of EZH2 in NEPC tumors has been pursued through various studies. An intriguing observation lies in the concurrent elevation of H3K27me3 alongside overexpression of EZH2in NEPC tumors, indicating the epi­genetic regulatory role of EZH2in these tumors. One direct objective of EZH2in NEPC tumors, subject to epigenetic silencing, is the inhibition of a pro-angiogenic inhibitor known as thrombospondin 1 (TSP1), as the reduction in TSP1 expression correlates with heightened EZH2 markers and NED [50, 51]. Given the more pro­nounced role of EZH2 in NEPC models compared to CRPC tumors, enzymatic EZH2 inhibitors exhibit improved efcacy in NEPC tumors [48]. Nevertheless, in order to achieve a 50% growth inhibition, the therapy still requires the administra­tion of large dosages of the inhibitors, roughly 5μM.This observation implies that methylation-independent PRC2 activities may play a signicant part in the process. Notably, several studies have shown a clear association between the androgen recep­tor and EZH2-mediated epigenetic suppression in NEPC cells lacking the androgen receptor. Furthermore, it has been indicated that utilizing EZH2 inhibitors reinstates the transcription of the androgen receptor [52, 53]. While the reduction of EZH2 and its enzymatic inhibitors elicit contrasting effects in androgen receptor-positive cells, both of these alterations lead to an increase in androgen receptor levels within NEPC cells. It appears that as prostate cancer progresses to NEPC, the role of androgen receptor activation mediated by EZH2 diminishes, which could contribute to the emergence of the AR-negative nature of NEPC cells. However, recent nd­ings indicate that EZH2 inhibitors have the potential to restore the sensitivity of NEPC cells to ARPI, hence conrming the rationale for their combined administra­tion. The concurrent administration of GSK503 and enzalutamide had a synergistic impact on the inhibition of tumor development in post-castration double knockout (DKO) models with Pten and Rb1 deletion [7].

RNA–STING–ISG activation, leading to an increase in genes associated with anti­gen presentation, Th1 chemokine signaling, and interferon response [72, 73]. This includes the upregulation of programmed cell death protein 1 (PD-L1), which is reliant on stimulator of interferon genes (STING) activation. Consequently, EZH2 inhibition signicantly enhances the migration of activated CD8+ T cells within tumors and boosts the presence of M1 tumor-associated macrophages, effectively overturning resistance to PD-1 CPI treatment. Their research highlights EZH2’s substantial role as a suppressor of anti-tumor immunity and its impact on the effec­tiveness of CPI treatment. These ndings propose EZH2 inhibition as a viable thera­peutic approach for augmenting the response of prostate cancer to PD-1 CPI treatment [74].