Organoid-immune cell culture modeling of therapeutic responses in cholangiocarcinoma

Intrahepatic cholangiocarcinoma (iCCA) is a devastating liver cancer with limited therapeutic options. While immune checkpoint inhibitors (ICIs) alone are ineffective in iCCA, the combination of ICIs with standard chemotherapy has recently become the new standard-of-care (soc). However, ~75% of iCCA patients present with primary resistance to the soc, emphasizing the critical need to identify underlying mechanisms of resistance and design more effective ICI combinations. Tumor genotype plays a critical role in iCCA immunogenicity, therapeutic resistance, and composition of the tumor microenvironment (TME), highlighting the need for precision models that (1) capture the genetic complexity of primary tumors, (2) reproduce patient-specific tumor- TME interactions, and (3) enable high-throughput immunotherapy screening. Current preclinical models fail to fully recapitulate these features. To address this gap, we have developed a novel co-culture system that allows the simultaneous reconstitution of iCCA patient-derived organoids (PDOs) with multiple autologous TME components, here called PDOTs. Our PDOT system integrates key stromal and immune components, providing a more physiologically relevant platform for immunotherapy testing. Our preliminary data show that iCCA PDOTs: (1) preserve the malignant programs and spatial cellular interactions of primary tumors; (2) reproduce real-life clinical response; and (3) identify surrogates of resistance to current ICIs that can be targeted to improve therapeutic efficacy. Based on these exciting preliminary data, our objective is to demonstrate the translational utility of our newly developed PDOT system in guiding the personalized design of effective immunotherapies that will ultimately improve the outcome, quality of life, and prognosis of patients afflicted by this devastating disease. Our central hypothesis is that PDOTs faithfully model the malignant programs and mechanisms of resistance to the soc chemoimmunotherapy in iCCA, and thus represent a valuable platform to test the preclinical efficacy of rational combination strategies able to improve patient responses. Thanks to the strategic position of Mt Sinai Hospital – a leading US center in the number of new liver cancer patients evaluated annually, including iCCA, – we are uniquely positioned to pursue the following Specific Aims. In Aim 1, we will establish a biobank of 50 iCCA PDOs and matched autologous immune and stromal components to assess their molecular and functional fidelity to primary tumors. In Aim 2, we will use PDOTs derived from 36 biopsies of iCCA patients prior to soc treatment to uncover cellular and molecular mechanisms of resistance and design rational combination therapies that improve patient responses. With over 70% of iCCA patients displaying primary resistance to the current ICI- based soc, investigating mechanisms of innate resistance presents a major unmet need in this disease. The completion of this study will provide an unprecedented framework to accelerate the development of precision immuno-oncology therapies for patients with iCCA and potentially other cancers, and open new horizons into translational studies aimed at developing more effective combination strategies in a patient-specific way. Project Number: 1R01CA285425-01A1 | Fiscal Year: 2026 | NIH Institute/Center: National Cancer Institute (NCI) | Principal Investigator: Daniela Sia (+1 co-PI) | Institution: ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI, NEW YORK, NY | Award Amount: $628,394 | Activity Code: R01 | Study Section: Special Emphasis Panel[ZRG1 CTH-B (55)] View on NIH RePORTER: https://reporter.nih.gov/project-details/11296375