FGF12 Enhances Prostate Cancer Cell Survival via the YB1-lncRNA Axis.

Treatment-induced neuroendocrine prostate cancer (t-NEPC) is a highly aggressive and therapy-resistant subtype of prostate cancer characterized by lineage plasticity and poor response to standard chemotherapy and androgen deprivation therapy. Although transcriptional mechanisms driving t-NEPC have been extensively studied, the contribution of post-transcriptional regulation remains less defined. Here, we report fibroblast growth factor 12 (FGF12) as a critical post-transcriptional regulator of t-NEPC progression. Transcriptomic analyses of patient biopsies, patient-derived xenografts, and prostate cancer cell models consistently demonstrated elevated FGF12 expression in t-NEPC, which was further validated by immunohistochemistry in archival specimens. Functional assays revealed that FGF12 expression conferred survival of cancer cells to chemotherapeutic agents, including etoposide and camptothecin. Integrative RNA sequencing and affinity purification-mass spectrometry showed that FGF12 mediates these functions mainly through interaction with the RNA-binding protein YB1, leading to stabilization of oncogenic long noncoding RNAs, including NEAT1 and MALAT1, whereas RNA silencing of YB1 abrogated the ability of FGF12 to upregulate these transcripts. Collectively, these findings uncover a previously unrecognized FGF12-YB1-lncRNA signaling axis that drives t-NEPC progression. Targeting this pathway may provide new therapeutic opportunities for patients with this aggressive disease.