Nanoparticle-mediated cytokine targeting to overcome immunosuppression and improve immunotherapy in prostate cancer

Background. Prostate Cancer (PC) is a leading cause of cancer deaths among men worldwide. Mortality is mainly due to metastatic disease, especially to the bones, with no effective therapies available. Overcoming resistance of advanced disease to current immunotherapeutic strategies is challenging. Interleukin (IL)-30/IL-27p28 promotes PC-Stem-like-Cell tumorigenicity and dissemination to the bone marrow (BM), and fosters PC immune evasion through induction of cancer-cell expression of KIT Ligand, TLR3, Myd88, Foxp3, PD-L1, and mediators that promote myeloid-derived cell (MDC) accumulation and suppressive functions. IL-30 knock-down decreases intra-tumoral MDCs and prevents or delays PC onset and progression. Hypothesis. IL-30 is involved in cross-talk between cancer cells and MDCs and has a crucial role in the immunosuppressive microenvironment that restrains T-cell immune reactivity during PC progression. Targeting IL-30 might restore immune-reactivity and improve responses to anti-cancer immunotherapies. Aims of the Project are: −Definition of the mechanisms underlying the role of IL-30 in shaping the tumour microenvironment (TME) during PC progression, and in particular, in the regulation of cross-talk between cancer cells and MDCs. −Determination of production of and response to IL-30 by intra-tumoral and peripheral MDCs, and analysis of effects of IL-30 on MDC and T lymphocyte survival, differentiation, recruitment and functions. −Determination of whether IL-30 targeting rescues the TME from immunosuppression, boosts immune reactivity, and hinders tumour progression, using a murine model of PC that mimics human PC. −Improvement of responses to selective targeting of negative checkpoint regulators by co-targeting IL-30 in PC and its TME. −Determination of effectiveness of a co-targeting approach in human PC-derived 3D-organoids and 2-Organ-(PC/BoneMarrow)-Chip that reproduces the microenvironment, genetic and immunophenotypic features of the primary tumour and BM from a specific patient. Experimental Design plans: −Determination of IL-30 regulation of the immune-related gene signature and PC progression in Ptennull/EIIa-p28f/fmice, where loss of PTEN in the prostatic epithelium is associated with loss of IL-30. −Determination of the impact of IL-30 on the viability and immune signature of a PC-derived 3D-organoid co-culture with MDCs and T lymphocytes. −Targeting of IL-30 in PC in Ptennullmice using newly designed asymmetric lipid nanocomplexes loaded with the Cas9/gRNA that targets IL-30, and conjugated with anti-PSCA-Abs that will be delivered to tumour sites. −Determination of whether targeting of IL-30 in PC of Ptennull mice or patient-derived organoid co-cultures with autologous MDCs and T lymphocytes, and 2-Organ-(PC/BoneMarrow)-Chip models, can improve responses to checkpoint blockade with Cas9g/RNA targeting PD-L1, or different negative checkpoint regulators. Expected Results. Definition of the mechanisms whereby IL-30 shapes the TME during PC progression, and of the proof of concept that targeting IL-30 restores immune reactivity, improves responses to immunotherapy and prevents/inhibits PC progression and metastases. Impact on cancer lies on −robust preliminary data on the effectiveness of knocking-out IL-30 to abrogate immunosuppression, −the use of a murine and two patient-derived in vitro models to test the therapeutic strategy, which allows achieving results in a short time frame. This study paves the way to patient-tailored immunotherapy for advanced PC, by using FDA-approved, next-generation nanocomplexes for selective co-targeting of IL-30 and negative checkpoint regulators, to limit side effects and improve patient benefits.