Insulin-like growth factor binding protein-3 serves as a biomarker for resistance to enzalutamide in prostate cancer.

Enzalutamide resistance (EnzR) is a major challenge in the current treatment of castration-resistant prostate cancer, as tumors frequently progress to drug resistance after an initially effective treatment. Therefore, there is an urgent need to characterize the genes alterations that accompany EnzR in prostate cancer and to identify new therapeutic targets. In this study, we analyzed a total of 1273 publicly available transcriptomics datasets from patients who underwent prostate cancer surgery. We investigated transcriptomic changes after enzalutamide (ENZ) treatment, identified key genes involved in the process of EnzR, and developed EnzR scores to predict tumor progression. We further investigated the role of IGFBP3 in the regulation of EnzR in prostate cancer. The effect of IGFBP3 expression level on the malignant degree of EnzR cells was explored in vitro. In addition, we explored the downstream mechanism of IGFBP3 involvement in EnzR. We found that epithelial-mesenchymal transition (EMT), cancer stem cell-like properties, and neuroendocrine transformation occurred in tumor cells after ENZ treatment. Subsequently, we developed and validated EnzR scores to predict prostate cancer tumor progression. Furthermore, we experimentally confirmed that IGFBP3 promotes the proliferation of drug-resistant cells and enhances ENZ resistance via EMT signaling. Overall, we established a new EnzR scoring model through multidimensional analysis of EnzR patterns. This model can accurately predict the clinical prognosis of prostate cancer patients after surgery. Moreover, IGFBP3 can be used as a potential therapeutic target for ENZ resistance in prostate cancer.