Recent advances in organoid technology have revolutionized cancer biology and therapeutic interventions, offering personalized immunotherapy treatment. Organoids, three-dimensional cell cultures derived from patient tumors, accurately replicate the tumor microenvironment, providing unprecedented insights into tumor-immune interactions and therapeutic responses. In this literature-based study, we discuss various culture methods for the diverse applications of organoids in cancer immunotherapy, including drug screening, personalized treatment strategies, and mechanistic studies. Additionally, we address the technological challenges associated with these methods and propose potential future solutions to accelerate the development of novel immunotherapeutic approaches. This review highlights the transformative potential of organoid models in advancing preclinical cancer immunotherapy modeling, screening, and evaluation, paving the way for more effective and personalized cancer treatments.
Cancer immunotherapy represents a transformative approach in oncology, harnessing the body’s immune system to recognize and eradicate cancer cells. Unlike traditional treatments such as chemotherapy and radiation, which non-specifically target rapidly dividing cells, immunotherapy offers a more precise mechanism, aiming to enhance the immune system’s natural ability to combat cancer. This specificity not only promises improved efficacy but also minimizes the adverse side effects commonly associated with conventional treatments. Clinically, immunotherapy has shown remarkable success in treating various cancers, including melanoma, non-small cell lung cancer, and certain types of lymphoma, marking a significant advancement in cancer care.
In recent years, the development of organoid culture systems has emerged as a pivotal tool for advancing cancer immunotherapy. Organoids, three-dimensional structures derived from patient tissues, closely mimic real organs’ architecture and function, providing a realistic platform for studying tumor biology and the tumor-immune microenvironment. These models bridge basic research and clinical application, significantly advancing our understanding of immune cell interactions within tumors. By co-culturing organoids with immune cells, researchers can observe cell migration and activation, test immune checkpoint inhibitors, and optimize immunotherapies before clinical trials.
Despite the promise of cancer immunotherapy, there remain substantial challenges that limit its efficacy for all patients. Tumor heterogeneity, immune evasion mechanisms, and variability in patient responses are significant obstacles. Additionally, the current preclinical models often fail to accurately replicate the complexity of human tumors, impeding the translation of promising therapies from bench to bedside. These limitations underscore the urgent need for more predictive and representative models to facilitate the development of effective immunotherapies.
This review aims to address the intersection of biotechnology and clinical application by exploring the role of organoid cultures in cancer immunotherapy. We will provide a comprehensive overview of the current landscape of immunotherapy, discuss the advancements and potential of organoid models in enhancing our understanding of the tumor-immune interface, and highlight how these models can be leveraged to overcome existing clinical challenges. Through this exploration, we aim to underscore the importance of integrating innovative biotechnological tools in the pursuit of more effective and personalized cancer treatments.
Immunotherapy is an advanced cancer treatment that leverages the patient’s immune system to combat malignancies. This strategy enhances or modifies immune functionality, improving its ability to detect and destroy cancer cells. The five main categories of immunotherapy are oncolytic virus therapies, cancer vaccines, cytokine therapies, immune checkpoint inhibitors, and adoptive cell transfer. Oncolytic virus therapies use genetically modified viruses to selectively infect and destroy cancer cells. The viruses replicate within the cancer cells, causing cell lysis and releasing new viral particles to infect neighboring cells, turning tumors into a more antigenic form and triggering a systemic immune response. Cancer vaccines stimulate the immune system to target tumor-associated antigens (TAAs) on cancer cells. Administered via intradermal injection, they activate dendritic cells, which present the antigens to T cells, leading to the proliferation of cytotoxic T lymphocytes (CTLs) that seek out and kill cancer cells, while helper T cells enhance the overall immune response. Cytokine therapies use small proteins that play vital roles in immune signaling to enhance the anticancer immune response, boosting T cell activation, promoting antigen presentation, and modulating the tumor microenvironment. Immune checkpoint inhibitors block interactions between checkpoint proteins and their ligands, such as PD-1/PD-L1 and CTLA-4/CD80, preventing inhibitory signals and allowing T cells to maintain their cytotoxic activity, improving their ability to recognize and eliminate cancer cells. Adoptive cell transfer (ACT) involves infusing patients with genetically modified T cells tailored to recognize cancer-specific antigens, engineered with T cell receptors (TCRs) or chimeric antigen receptors (CARs), which enhances their ability to target and destroy cancer cells.
The use of patient-derived organoids in personalized cancer immunotherapy has shown great promise. These organoids retain the genetic and functional characteristics of the original tumors, allowing for the tailoring of immunotherapeutic strategies to each patient’s unique cancer profile. By testing different immunotherapies on these personalized models, clinicians can predict the most effective treatments, improving patient outcomes. Case studies, such as those involving colorectal and breast cancer, have demonstrated that organoid-based approaches can accurately guide personalized treatment plans, leading to significant tumor regression and enhanced clinical results.
Votanopoulos et al. engineered a novel 3D mixed melanoma/lymph node organoid system to enable personalized immunotherapy screening by preserving tumor heterogeneity and the immune microenvironment. Surgically obtained matched melanoma and lymph node biospecimens from the same patients were dissociated, incorporated into an extracellular matrix-based hydrogel, and biofabricated into immune-enhanced patient tumor organoids (iPTOs). This method retained the original tumor’s stroma and immune cells without sorting. The organoids were screened with various immunotherapies (nivolumab, pembrolizumab, ipilimumab, and dabrafenib/trametinib) over 72 h, and their responses were assessed using live/dead staining and quantitative metabolism assays. Histology and immunohistochemistry confirmed the resemblance between the original tumor and the organoid cells. In a pilot study, autologous peripheral T cells activated by iPTOs successfully killed tumor cells in naïve PTOs, indicating the generation of adaptive immunity. The study demonstrated a high establishment success rate (90%) and a strong correlation (85%) between iPTO response and clinical outcomes, showcasing its potential as a personalized immunotherapy testing platform.
Forsythe et al. (2021) conducted a pioneering study to evaluate the efficacy of immunotherapy for appendiceal cancer using a personalized organoid model, addressing the scarcity of clinical trial data due to the cancer’s low incidence. They created patient tumor organoids (PTOs) with and without enrichment from immune components and treated them with pembrolizumab, ipilimumab, or nivolumab. The study showed that immunotherapy responses were observed in some cases, particularly with pembrolizumab and nivolumab, but not with ipilimumab. This research demonstrates the potential of immunotherapy for appendiceal cancer and the usefulness of immunocompetent organoids in selecting patients for clinical trials in rare cancers.
The organoid model for immunotherapy incorporates key cellular components to faithfully replicate aspects of the tumor microenvironment. Derived from patient tumor biopsies, tumor cells form the foundational component, preserving genetic and phenotypic characteristics essential for modeling personalized cancer scenarios. Immune cells such as T cells, natural killer (NK) cells, and macrophages play a crucial role in studying immune-tumor interactions and can be autologous, ensuring the model’s relevance to individual patient responses. Cancer-associated fibroblasts (CAFs), which provide structural support and secrete signaling molecules, mimic the tumor’s supportive microenvironment and influence immune cell behavior. Endothelial cells within the organoid form vascular-like structures, enabling investigations into angiogenesis and the infiltration dynamics of immune cells within the tumor environment. Together, these components create a comprehensive model that enhances our understanding and testing of immunotherapeutic strategies against cancer.
There are multiple organoid culture strategies for modeling the tumor immune microenvironment, which can be broadly categorized into reconstitution approaches and holistic approaches. The reconstitution approach involves reconstituting the tumor microenvironment with immune components, such as in submerged Matrigel culture. This method incorporates specific elements of the tumor and immune system into a controlled environment, allowing interactions between cancer cells and immune cells. In contrast, holistic approaches aim to maintain the native tumor microenvironment (TME) with its immune components intact. Examples include microfluidic 3D culture and air-liquid interface (ALI) culture. These methods preserve the complexity and heterogeneity of the TME, more closely mimicking patient conditions. By maintaining the original structure and composition of the tumor and its surrounding immune cells, holistic approaches provide a more accurate representation of how tumors interact with the immune system in the body, thereby enhancing the relevance of findings from organoid studies to clinical scenarios.
The extracellular matrix (ECM) forms the structural foundation for organoid formation, comprising proteins such as collagen, laminin, and fibronectin. Matrigel, a widely used hydrogel, mimics natural ECM properties by supporting cell attachment, growth, and differentiation within organoids. Additionally, ECM components play a crucial rol
