Mechanistically, MYC suppression is associated with transcriptional regulation by ASCL1, while MYCL upregulation appears to occur within a permissive epigenetic landscape rather than through genomic amplification. Together, these findings identify MYCL as a lineage-specific regulator that drives and maintains neuroendocrine identity and define a MYC family regulatory switch in which MYCL replaces MYC to stabilize neuroendocrine lineage programs in advanced prostate cancer.
We further identify ASCL1 and INSM1 as upstream regulators of MYCL, establishing a conserved neuroendocrine transcriptional axis. Together, these findings define MYCL as a lineage-specific regulator that drives neuroendocrine identity and plasticity in advanced prostate cancer.
Multivariate analysis also confirmed that co-expression of MYC/MYCL/MYCN was significantly associated with the prognosis of lung, gastric, liver, and breast cancers. Taken together, our results demonstrate that the MYC family can function not only as an oncogene but also as a tumor suppressor gene in various cancers, which could be used to develop a novel approach to cancer treatment.