Key points are not available for this paper at this time.
Abstract Prostate cancer (PCa) is American men's second most common cancer. Although taxane-based chemotherapy is the last line of defense for Metastatic Castration Resistant Prostate Cancer (mCRPC), it invariably fails due to chemoresistance. The protein-specific membrane antigen (PSMA) has been an effective target for the imaging and therapy of mCRPC. Although PSMA radioligand therapy (PSMA-RLT) is a theranostics option for men with advanced PCa, about 30% have a limited response due to neuroendocrine-like PCa (NEPC), which lacks PSMA expression. Enolase (ENO) is a promising theranostic alternative due to its cell surface localization in many human tumors. We observed that chemosensitive PCa cell lines expressing NEPC markers express both ENO-1 and ENO-2; however, docetaxel-resistant NEPC-like cells only express ENO-1 and have a metabolic vulnerability due to the loss of ENO-2. We hypothesize that ENO-1 is expressed on the surface of NEPC-like cell lines and can be targeted with small molecule inhibitors (SMIs) that could potentially be used as theranostics agents. Additionally, we have observed changes in the expression and localization of ENO-1 in NEPC-like cell lines under different glucose concentrations. Our data show that under high glucose conditions, found on metabolically active metastatic tumors, ENO-1 is highly expressed on the cell surface, making it a promising candidate target for theranostics. However, low glucose conditions inhibit the activity of the c-MYC oncogene resulting in ENO-1 downregulation and upregulation of MBP1, the small splice variant of ENO1 that blocks the transcriptional activity of c-MYC. Our efforts to confirm ENO-1 surface expression on NEPC-like cell lines entailed using confocal microscopy, cell fractionation analysis followed by Western blotting, and Flow cytometric cell surface staining. We also evaluated the cytotoxicity of SMIs designed to target ENO-1 in chemoresistant NEPC-like cell lines using MTT viability assays, clonogenic assays, and Hoffman Modulation microscopy imaging. Our long-term goal is to identify an alternative treatment for patients with NEPC by establishing ENO-1 as a novel theranostics target. Citation Format: Krystal Rubi Santiago Torres, Carlos A. Casiano, Frankis Almaguel, Alfonso Duran, Kristen Whitley. Surface localization of enolase-1 (ENO-1) as an attractive theranostic target in docetaxel-resistant neuroendocrine-like prostate cancer cells abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 4697.
Torres et al. (Fri,) studied this question.