Pd35-04 Targeting Lineage Reprogramming in Neuroendocrine Prostate Cancer: The Role of Nitric Oxide-Modulated Molecular Interactions

You have accessJournal of UrologyProstate Cancer: Basic Research & Pathophysiology III (PD35)1 May 2024PD35-04 TARGETING LINEAGE REPROGRAMMING IN NEUROENDOCRINE PROSTATE CANCER: THE ROLE OF NITRIC OXIDE-MODULATED MOLECULAR INTERACTIONS Fakiha Firdaus, Osmel Companioni Napoles, Khushi Shah, Ranjith Ramasamy, and Himanshu Arora Fakiha FirdausFakiha Firdaus , Osmel Companioni NapolesOsmel Companioni Napoles , Khushi ShahKhushi Shah , Ranjith RamasamyRanjith Ramasamy , and Himanshu AroraHimanshu Arora View All Author Informationhttps://doi.org/10.1097/01.JU.0001009396.21455.74.04AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Neuroendocrine prostate cancer (NEPC) is a highly aggressive and therapy-resistant subtype of prostate cancer. The resistance to most chemo and radiotherapy options in NEPC has been linked to lineage reprogramming, a mechanism through which the cancer cells manipulate their phenotype to become metastatic. However, the key molecular interactions that could re-regulate the lineage reprogramming and reduce the NEPC stemness remain understudied and are the basis of this study. In this context, our studies have explored the role of Nitric oxide (NO), a small, short-lived molecule produced by nitric oxide synthases, against castration-resistant prostate cancer (CRPC) and how it has efficacy in reducing the secondary tumors and restoring transcriptional network in CRPC. In this study, we delineated the NO-modulated molecular interactions that are specific to lineage reprogramming in NEPC models. METHODS: For the in vitro study, we treated Primary prostate cancer (Pca) cells line, LNCaP, CRPC cells (22RV1), and NEPC cell lines DU145 and H660 with NO donor, S-nitrosoglutathione (GSNO) at the dosage of 50 uM for 2-4 days. We sorted ALDH+ cancer stem cells by flow cytometry. These cells were used to perform colony formation and apoptosis assays. For the in vivo study, castrated SCID mice were grafted with H660 cells to generate NEPC murine models (two groups). Group 1 received vehicle (Control), and group 2 received GSNO treatment (10mg/kg/day intraperitoneally (ip)). Treatment was performed daily for six weeks, and tumor growth was measured once a week. Blood, lungs, spleen, liver, bones, and tumors were harvested for further study. Moreover, tumors from the control group were subjected to sorting for ALDH+ and ALDH- cells and were grafted to another set of castrated SCID mice which were again divided into control and GSNO treatment groups. The treatment was conducted for about 6 weeks before humanely euthanizing the mice and collecting blood, lungs, spleen, liver, bones and tumors for further study. RESULTS: For the in-vitro study, we observed that the most significant reduction in ALDH+ cells was observed in NEPC cells only, compared to Primary or CRPC cell lines. Additionally, colony formation and apoptosis assay results highlighted similar observations (a significant reduction in number of colonies and an increase in overall apoptosis in ALDH+ cells derived from NEPC cells). In-vivo results highlighted that treatment with GSNO reduced the overall NEPC tumor burden (p<0.05) as compared to the control. Moreover, the metastasis was reduced in the brain (p<0.05) in the GSNO treatment group. Importantly, in ALDH+ tumor grafts that received GSNO treatment in the second in-vivo experiment demonstrated a significant reduction in lung and liver metastasis despite this group not showing an overall difference in the tumor burden. Furthermore, the RNA sequencing analysis of ALDH+ tumors highlighted important molecular interactions; we found an important interaction between DOT1L-nMYC, which is centrally regulated by E2 ligases within NEPC stem cells. We demonstrated that ALDH+ tumor grafts subjected to GSNO treatment could increase the E2 ligases and, therefore, inhibit DOT1L and nMYC. CONCLUSIONS: This study shows that exogenous treatment with nitric oxide donor suppresses the NEPC stem cells and the expression of MYC and DOT1L in these cells by increasing the ubiquitin ligases. Source of Funding: American Cancer Society; Sylvester Cancer Center © 2024 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 211Issue 5SMay 2024Page: e726 Advertisement Copyright & Permissions© 2024 by American Urological Association Education and Research, Inc.Metrics Author Information Fakiha Firdaus More articles by this author Osmel Companioni Napoles More articles by this author Khushi Shah More articles by this author Ranjith Ramasamy More articles by this author Himanshu Arora More articles by this author Expand All Advertisement PDF downloadLoading ...