Abstract 6499: Miniaturized 3D cancer models for measuring efficacy of cancer therapeutics

Abstract Whilst Chimeric Antigen Receptor T-cell (CAR-T) therapy has been proven beneficial in treatinghaematological malignancies and melanoma, their clinical success against the majority of solidtumour types has been limited thus far. The need for physiologically relevant 3D, complex in vitromodels of cancer is steadily increasing due to the emergence of drugs targeting the immunesystem and the tumor microenvironment (TME). Current in vivo and in vitro models are notsufficiently representative of the human (TME) and can fail to accurately predict the clinicaloutcome of immunotherapies. Furthermore, an increasing interest in precision treatment of cancerpatients and the rise of anticancer therapies used in combination has highlighted the need forlarge-throughput 3D efficacy tests capable of maximizing data generation using very smallquantities of 3D tumour models, especially including those from clinical samples. To this aim, microfluidic and organ-on-a-chip technologies can facilitate mechanistic studies and, at the sametime, miniaturize investigation of therapy efficacy on relevant human tumor samples.This work aimed to develop novel, high-throughput and miniaturized efficacy assays todemonstrate CAR-T mediated cytotoxicity using the Her2 receptor, a common target over-expressed on many types of solid tumors. Her2+ and Her2- expressing cancer cells were culturedin 3D within UpScale3D microfluidic platforms (ScreenIn3D Ltd). Hundreds of spheroids wereformed within 48 hours and, subsequently, CAR-Ts with low and high affinity for the target(RoukenBio) were co-cultured with the spheroids over 72-hour incubation at the desired E:T ratio.Viability staining and cell type specific markers were used as readouts. Results showed that CAR-T quickly targeted, disaggregated and specifically killed high Her2+ expressing cells in 3D models.In contrast, CAR-T cells did not elicit statistically significant cytotoxicity in low/non-Her2+expressing spheroids. Immunotherapy treatment was compared to cytotoxicity elicited bychemotherapy agent carboplatin.This versatile microfluidic platform offers high quality and multiplexed efficacy screening assays onspheroid co-cultures, organoids and primary tumour fragments. The platform is designed for self-generation of multiple drug concentration gradients, offering a unique system to miniaturize drugcombination studies using patient’s tissue and, at the same time, creating cost-effective and fastimmune-oncology assays for extensive drug combination studies and precision medicine drugdiscovery. Citation Format: Jamie Hodgson, Hannah Findlay, Timothy London, Agapitos Patakas, Michele Zagnoni, Karla Paterson, Ronan Mellin. Miniaturized 3D cancer models for measuring efficacy of cancer therapeutics [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 6499.