FDA issued guidance on 10 April 2025 to phase out animal trials in favor of organoids and organ-on-a-chip systems. This pivotal move was swiftly followed by the National Institutes of Health (NIH) on April 29th, when it inaugurated the Office of Research Innovation, Validation, and Application (ORIVA). The establishment of ORIVA aims to spearhead the advancement of human-centric organ-on-a-chip technologies, marking a major stride toward more accurate, ethical, and efficient research methods in the biomedical field. Compared to traditional 2D cell cultures and animal models, organ-on-a-chip systems enable precise control of hydrodynamic parameters and biomechanical microenvironments. This review systematically elaborates on applications of single-organ, multi-organ, and organoid-on-a-chip technologies in modeling complex diseases, host–microbiome interactions, inter-organ physiological networks, and quantitative prediction of pharmacokinetics, toxicity responses, and personalized therapies. Furthermore, the core challenges in translating these technologies to pharmaceutical development and clinical practice are critically analyzed. With interdisciplinary integration of materials engineering, biosensing, and artificial intelligence, organ-on-a-chip technologies are transcending the limitations of conventional preclinical research. Their strategic value as "patient surrogates" is poised to accelerate breakthroughs in precision medicine and rare disease treatments.

Human tumor organoids represent a paradigm shift in cancer modeling, overcoming critical limitations of conventional systems by faithfully recapitulating genetic heterogeneity, three-dimensional architecture, and tumor microenvironment dynamics of patient tumors. Our review explores how human tumor organoids serve as a transformative preclinical platform, bridging the gap between basic research and clinical translations. We highlight recent advances in tumor organoid generation, spanning patient-derived organoids to genetically engineered platforms from normal tissue and human pluripotent stem cells, and their applications in deciphering carcinogenesis, clonal evolution, and metastatic mechanisms. We further examine technological innovations in culture systems that enhance the interpretability and translatability of tumor phenotypes and drug responses. We present an in-depth exploration of how integrated tumor microenvironment co-culture systems—combining immune cells, cancer-associated fibroblasts, and vascular components–enable novel investigations into tumor-stroma-immune crosstalk. Clinically, human tumor organoid biobanks have shown great promise in predicting personalized therapy responses. Emerging technologies like organoids-on-chip platforms, three-dimensionally bioprinting and artificial intelligence-driven analytics are enhancing high-throughput drug screening efficiency and biomarker identification. Despite advances, complete microenvironmental modeling remains challenging, particularly in replicating vascular complexity and systemic immune responses. Future advancements will demand convergence of synthetic biology, functional genomics, and machine learning to transform human tumor organoids from static avatars into dynamic “living biosensors”. In summary, this review provides an in-depth exploration of the organoid field and presents a clear and actionable framework for positioning tumor organoids as indispensable tools in functional precision medicine—a strategy that ultimately bridges mechanistic discoveries with clinical translation.

Impaired wound healing and pathological scarring remain major clinical challenges, with immune cell dysregulation being a key driver of disease progression. Conventional in vitro models fail to recapitulate human immune responses, limiting their translational relevance. In recent years, advances in tissue engineering and microfluidic technologies have driven growing efforts to incorporate immune cells into in vitro models, thereby improving their ability to mimic pathological microenvironments. Among these, organ-on-a-chip technology stands out for its capacity to replicate dynamic perfusion, mechanical stimulation, and multicellular crosstalk—features critical for modeling immune-mediated wound repair. This review systematically summarizes recent progress in immune cell-integrated models of aberrant wound healing, including two-dimensional co-cultures, three-dimensional static cultures, organoid systems, and organ-on-a-chip platforms. We highlight core strategies for immune cell integration and their roles in recapitulating key pathological processes such as inflammation and fibrosis. Despite ongoing challenges in cell source stability, model standardization, and long-term culture viability, emerging strategies (e.g., organ-on-a-chip combined with three-dimensional bioprinting or modular design) offer new opportunities for creating biomimetic, high-throughput platforms for wound research. This review aims to facilitate the adoption of immune-integrated in vitro models in wound healing research, deepen mechanistic understanding of immune-driven pathology, and accelerate the development of precision therapeutics.

The ketogenic diet (KD), an emerging nutritional intervention for cancer, reprograms cellular energy metabolism from glucose to ketone bodies, including acetoacetate (AcAc), acetone (Ac), and β-hydroxybutyrate (BHB). However, the mechanisms connecting ketone body signal sensing to tumor growth suppression remain elusive. Here, we show that RagC, a key component of mTORC1 pathway, senses BHB but not AcAc and Ac, to dictate tumor suppression. KD-derived BHB inhibits mTORC1 activity by promoting β-hydroxybutyrylation (Kbhb) of RagC at lysine 349 (K348 in mice). Mechanistically, RagC-K349bhb is dynamically catalyzed by p300 and erased by SIRT1, disrupting RagC interaction with Raptor/mTOR and blocking mTORC1 recruitment to lysosomes. Clinically, BHB-mediated RagC-K349bhb suppresses colorectal cancer (CRC) growth via mTORC1 inhibition in both RagC-K348R knockin mice and CRC patient-derived samples. Thus, we identify a BHB sensing mechanism by mTORC1 and highlight the potential role of RagC-K349bhb as a therapeutic target for BHB-based CRC treatment.

Meibomian glands (MGs) are holocrine glands that secrete lipids to maintain the homeostasis of the ocular surface, and their dysfunction leads to dry eye disease. Herein, we established long-term 3D organoid culture for murine and human MGs, which retained the cell lineages and lipid-producing ability. The organoids mimicked the drug treatment responses and generated functional MGs after orthotopic transplantation. Inspired by organoid cultures, we found FGF10 eye drops could rescue all-trans retinoic acid-induced MG dysfunction in mice. Besides, nicotinamide uniquely hampered the human MG organoid expansion by inhibiting FGF10 signaling. Single-cell atlas and lipidome not only aligned the delineated cell types and featured lipids between human MGs and organoids, but also highlighted MAPK signaling inhibition enhanced acinar cell differentiation and functional maturation of MG organoids. In summary, this study established an organoid platform to explore epithelial homeostasis and dysfunction of MGs, facilitating drug development and regenerative medicine for dry eye disease.