Organoid engineering promises to revolutionize medicine with wide ranging applications of scientific, engineering, and clinical interest, including precision and personalized medicine, gene editing, drug development, disease modeling, cellular therapy, and a basic understanding of human development. Organoids are a three-dimensional (3D), miniature, caricature of a target organ, are initiated with stem/progenitor cells, and are extremely promising tools to model organ function. The biological basis for organoids is that they foster stem cell-self renewal, differentiation, and self-organization, recapitulating tissue structure or function better than 2D systems. In this review, we first discuss the importance of epithelial organs and the general properties of epithelial cells to provide context for the liver, pancreas, and gall bladder and rationale for organoid cultures. Next, we develop a general framework to understand self-organization, tissue hierarchy, and organoid cultivation. For each of these areas, we provide historical context, and review both a wide range of biological and/or biophysical/mathematic perspectives that enhances understanding of organoids. Next, we review existing techniques and progress in hepatobiliary and pancreatic organoid engineering. To do this, we review organoids from both primary tissues, cell lines, and stem cells, and introduce engineering studies when applicable. Noninvasive assessment of 1 organoids can reveal underlying biology and enable improved assays for growth, metabolism, and function. Applications of organoid for cell therapy are also discussed. Taken together, we establish a broad strong scientific foundation for organoids and provide an in-depth review of hepatic, biliary and pancreatic organoids.

The retina, a crucial part of the eye, is made up of various cells and structures that are essential for the conversion of a light stimulus into an electric signal for the brain to develop an image. The different cells of the retina including the retinal pigment epithelium, rods and cones, and the retinal ganglion cells together are involved in the transduction of light and the formation of connections with the optic nerve. This is a complex and efficient system with distinct layers of cells being involved in the absorbing of unnecessary light stimulus and providing physiological support. Retinal disorders are most prevalent in people above the age of 50 and cases of blindness are in the millions, making the need for better treatment options a pressing matter. Shortage of donors and patient incompatibility are reasons for which the focus has moved to the use of stem cells and tissue engineering as an alternative treatment option. Induced pluripotent stem cells can be engineered to differentiate into retinal cells using supplements like SMAD antagonists and retinoic acid. Inactivating motor proteins and using Wnt/BMP4 antagonists facilitate the development of retinal neural characteristics to give three-dimensional retinal organoids. Microfluidics provides vascularization for better nutrient supply to make improved functional tissue models. Retinal organoids are hence promising for drug discovery and development, disease modeling, transplant alternatives, and developmental biology.

Hashimoto thyroiditis, also known as chronic autoimmune thyroiditis or chronic lymphocytic thyroiditis, is an autoimmune illness in which thyroid cells are damaged by immunological mechanisms involving cells and antibodies. Thyroid peroxidase and/or thyroglobulin autoantibodies in the serum are biochemical indicators of the condition, with females having a higher incidence than males and increasing with age. It's the leading cause of hypothyroidism in affluent countries. Inadequate dietary iodine intake, on the other hand, is the most common cause of hypothyroidism worldwide. The development of antithyroid antibodies that target the thyroid tissue, causing gradual fibrosis, is the pathogenesis of Hashimoto thyroiditis. The diagnosis can be difficult, and as a result, the problem is frequently not detected until late in the disease process. The most prevalent laboratory findings are raised TSH and low thyroxine (T4) levels, as well as enhanced antithyroid peroxidase (anti-TPO) antibodies. The pathogenesis, diagnosis, and management of Hashimoto thyroiditis are discussed in this article.

Microfluidic systems offer controlled microenvironments for cell-to-cell and cell-to-stromainteractions, which have precise physiological, biochemical, and mechanical features. The opti-mization of their conditions to best resemble tumor microenvironments constitutes an experimentalmodeling challenge, particularly regarding carcinogenesis in the central nervous system (CNS), giventhe specific features of the blood–brain barrier (BBB). Gel-free 3D microfluidic cell culture systems(gel-free 3D-mFCCSs), including features such as self-production of extracellular matrices, providesignificant benefits, including promoting cell–cell communication, interaction, and cell polarity. Theproposed microfluidic system consisted of a gel-free culture device inoculated with human brainmicrovascular endothelial cells (HBEC5i), glioblastoma multiforme cells (U87MG), and astrocytes(ScienCell 1800). The gel-free 3D-mFCCS showed a diffusion coefficient of 4.06 × 10−9 m2·s−1, and itreconstructed several features and functional properties that occur at the BBB, such as the vasculo-genic ability of HBEC5i and the high duplication rate of U87MG. The optimized conditions of thegel-free 3D-mFCCS allowed for the determination of cellular proliferation, invasion, and migration,with evidence of both physical and biochemical cellular interactions, as well as the production ofpro-inflammatory cytokines. In conclusion, the proposed gel-free 3D-mFCCSs represent a versatileand suitable alternative to microfluidic systems, replicating several features that occur within tumormicroenvironments in the CNS. This research contributes to the characterization of microfluidicapproaches and could lead to a better understanding of tumor biology and the eventual developmentof personalized therapies. (PDF) A Versatile Microfluidic Device System that Lacks a Synthetic Extracellular Matrix Recapitulates the Blood-Brain Barrier and Dynamic Tumor Cell Interaction. Available from: https://www.researchgate.net/publication/384802118_A_Versatile_Microfluidic_Device_System_that_Lacks_a_Synthetic_Extracellular_Matrix_Recapitulates_the_Blood-Brain_Barrier_and_Dynamic_Tumor_Cell_Interaction#fullTextFileContent [accessed Oct 10 2024].

A key component of efforts to identify the biological and drug-specific aspects that contribute to therapeutic failure or unexpected exposure-associated toxicity is the study of drug-intestinal barrier interactions. While methods supporting such assessments are widely described for human therapeutics, there is relatively little information available for similar evaluation in support of veterinary pharmaceuticals. There is, therefore, a critical need to develop novel approaches for evaluating drug-gut interactions in veterinary medicine. Three-dimensional (3D) organoids can address these difficulties in a reasonably affordable system that circumvents the need for more invasive in vivo assays in live animals. However, a first step in the development of such systems is understanding organoid interactions in a 2D monolayer. Given the importance of orally administered medications for meeting the therapeutic need of companion animals, we demonstrate growth conditions under which canine colonoid-derived intestinal epithelial cells survive, mature, and differentiate into confluent cell systems with high monolayer integrity. We further examine the applicability of this canine colonoid-derived 2D model to assess the permeability of three structurally diverse, passively absorbed β-blockers (e.g., propranolol, metoprolol, and atenolol). Both absorptive and secretive apparent permeability (Papp) of these drugs at two different pH conditions were evaluated in canine colonoid-derived monolayers and were compared with that of Caco-2 cells. This proof-of-concept study provides promising preliminary results with regard to the utility of canine-derived organoid monolayers for species-specific assessments of therapeutic drug passive permeability.

Hormones must be balanced and dynamically controlled for the Female Reproductive Tract (FRT) to function correctly during the menstrual cycle, pregnancy, and delivery. Gamete selection and successful transfer to the uterus, where it implants and pregnancy occurs, is supported by the mucosal epithelial lining of the FRT ovaries, uterus, cervix, fallopian tubes, and vagina. Successful implantation and placentation in humans and other animals rely on complex interactions between the embryo and a receptive female reproductive system. The FRT's recent breakthroughs in three-dimensional (3D) organoid systems now provide critical experimental models that match the organ's physiological, functional, and anatomical characteristics in vitro. This article summarizes the current state of the art on organoids generated from various parts of the FRT. The current analysis examines recent developments in the creation of organoid models of reproductive organs, as well as their future directions.

The emergence of three-dimensional human organoids has opened the door for development of patient-derived cancer organoid (PDO) models, which closely recapitulate parental tumor tissue. Mainstays of preclinical cancer modeling include in vitro cell lines and patient-derived xenografts, but these models lack the cellular heterogeneity seen in human tumors. Moreover, xenograft establishment is resource- and time-intensive, rendering these models difficult to use to inform clinical trials and decisions. PDOs, however, can be created efficiently and retain tumor-specific properties such as cellular heterogeneity, cell-cell and cell-stromal interactions, tumor microenvironment, and therapeutic responsiveness. PDO models and drug screening protocols have been described for several solid tumors and, more recently, for gliomas. Since PDOs can be developed in clinically relevant timeframes and share many characteristics of parent tumors, they may enhance the ability to provide precision oncologic care for patients. This review explores the current literature on cancer organoids, highlighting the history of PDO development, organoid models of glioma, and potential clinical applications of PDOs.

Recent advances in organoid technology have revolutionized cancer biology and thera-peutic interventions, offering personalized immunotherapy treatment. Organoids, three-dimensional cell cultures derived from patient tumors, accurately replicate the tumor microenvi-ronment, providing unprecedented insights into tumor-immune interactions and therapeutic re-sponses. In this literature-based study, we discuss various culture methods for the diverse appli-cations of organoids in cancer immunotherapy, including drug screening, personalized treatment strategies, and mechanistic studies. Additionally, we address the technological challenges asso-ciated with these methods and propose potential future solutions to accelerate the development of novel immunotherapeutic approaches. This review highlights the transformative potential of or-ganoid models in advancing preclinical cancer immunotherapy modeling, screening, and evalua-tion, paving the way for more effective and personalized cancer treatments.

Early detection of neurological conditions is critical for timely diagnosis and treatment. Identifying cellular-level changes is essential for implementing therapeutic interventions prior to symptomatic disease onset. However, monitoring brain tissue directly through biopsies is invasive and high-risk. Bodily fluids such as blood or cerebrospinal fluid contain information in many forms, including proteins and nucleic acids. Particularly, cell-free DNA (cfDNA) has potential as a versatile neurological biomarker. Yet, our knowledge of cfDNA released by brain tissue and how cfDNA changes in response to deleterious events within the brain is incomplete. Mapping changes in cfDNA to specific cellular events is difficult in vivo, where many tissues contribute to circulating cfDNA. Organoids are tractable systems for examining specific changes consistently in a human background. However, few studies have investigated cfDNA released from organoids. Here, we examined cfDNA isolated from cerebral organoids. We found that cerebral organoids release quantities of cfDNA sufficient for downstream analysis with droplet-digital PCR and whole-genome sequencing. Further, gene ontology analysis of genes aligning with sequenced cfDNA fragments revealed association with terms related to neurodevelopment and autism spectrum disorder. We conclude that cerebral organoids hold promise as tools for the discovery of cfDNA biomarkers related to neurodevelopmental and neurological disorders.

Arboviruses of medical and veterinary significance have been identified on all 7 continents with every human and animal population at risk for exposure. Like arboviruses, chronic neurodegenerative diseases like Alzheimer’s and Parkinson’s disease are found wherever there are humans. Viral parkinsonism has been documented for a variety of human pathogens though there are few studies that evaluate the effects of viral infection on degenerative neurological diseases. Significant differences in baseline gene and protein expression have been determined between Human Induced Pluripotent Stem Cell lines derived from a non-Parkinson’s disease individual and from an individual with reported Parkinson’s disease. While the organoids generated from each cell line were physically indistinguishable, significant differences were observed in gene and protein expression for neurotransmission and immunity. It was hypothesized that these inherent differences would impact cerebral organoid responses to viral infection. In this preliminary observational study, cerebral organoids from a non-Parkinson’s and Parkinson’s patient were infected with Chikungunya virus and observed for 2 weeks. Parkinson’s organoids lost mass and exhibited a dysfunctional antiviral response. Neurotransmission data from both non-Parkinson’s and Parkinson’s organoids had dysregulation of IL-1, IL-10, IL-6. These cytokines are associated with mood and could be contributing to persistent depression seen in patients following CHIKV infection. Both organoid types had increased expression of CCR5 and CXCL10 which are linked to demyelination, highlighting a potential mechanism for virus-associated parkinsonism. The dysfunctional antiviral response of Parkinson’s organoids highlights the need for more research in neurotropic infections in a neurologically compromised host.

The development of 3D cerebral brain organoids which accurately resemble aspects of the human brain permits a more accurate characterization of physiological processes and neurological diseases. Cerebral organoids can be grown from stem cell lines with various genetic backgrounds allowing multiple neurodegenerative diseases to be modeled. While dysfunction in neurotransmission of patients with neurodegenerative diseases is expected, the impact of chronic neurodegeneration on the response to viral infection of the CNS is poorly understood. For instance, several mosquito-borne viruses like Dengue virus and West Nile Virus cause post-viral parkinsonism. How CNS infection might impact a host with inherent CNS dysfunction such as Parkinson’s Disease in poorly understood. This preliminary, observational study aimed to understand dysfunction in intrinsic and innate expression of a patient with a neurodegenerative disease and a non-affected individual in relation to potential viral infection in the CNS. Cerebral organoids were generated from human induced pluripotent stem cells with a normal genetic background or with idiopathic Parkinson’s Disease. After differentiation and maturation, organoid size, gene expression and immunofluorescence were evaluated to assess neurotransmission and innate immunity. While there was no significant difference in size of the organoids with a normal or Parkinson’s genetic background, gene expression studies identified multiple differences in innate immunity and neurotransmission. Immunofluorescence also identified differences in protein expression related to neurotransmission and innate immunity. Of note, organoids derived from a Parkinson’s patient exhibited endogenous up-regulation of dopamine and muscarinic acetylcholine receptors, GABA, glycine, and glutamate targets, and the majority of cytokines. This expression pattern suggests a chronic state of neuroexcitation and neuroinflammation in this population of organoids.

Articular chondrocytes are surrounded by chondroitin sulfate proteoglycan, which attracts an abundant volume of interstitial water. The articular cartilage is compressed with joint-loading and weight-bearing stresses, followed by a bulging of the tissue during times of off-loading. Thus, osmotic pressure in articular cartilage is higher than in other tissues due to the fixed charged density and altered between loading and off-loading due to change in water content. Another unique characteristic of the articular cartilage is that it has longitudinal depth: surface, middle, and deep zones. Since each zone composes unique components of extracellular matrices, each zone has a various level of the osmotic pressure. It was unclear how changes in osmotic pressure affected chondrocyte homeostasis and matrix accumulation in specific longitudinal zone. We hypothesized that change in extrinsic osmotic pressure alters metabolic functions and histogenesis of extracellular matrix by zone-specific chondrocytes. We compared the gene expression of matrix related typical anabolic and catabolic molecules produced by zone specific articular chondrocytes and the immunohistology of these corresponding genes. Since the newly synthesized matrix needed a space to accumulate, we used a chondrocyte-spheroid model formed by longitudinal depth zone-derived cells and altered extrinsic osmotic pressure by changing media containing different osmotic pressures. Anabolic molecules upregulated continuously at high osmotic pressure and transiently by switching back the osmotic pressure from high to low. Each zone derived chondrocytes showed zone specific level of the gene expression. The spheroids once exposed to the high osmotic pressure accumulated extracellular matrices with empty spaces.

Prior to clinical trials, preclinical testing of oncology drug candidates is performed by evaluating drug candidates with in vitro and in vivo platforms. For in vivo testing, animal models are used to evaluate the toxicity and efficacy of drug candidates. However, animal models often display poor translational results as many drugs that pass preclinical testing fail when tested in humans, with oncology drugs exhibiting especially poor acceptance rates. The FDA Modernization Act 2.0 promotes alternative preclinical testing techniques, presenting the opportunity to use higher complexity in vitro models as an alternative to in vivo testing, including 3D cell culture models. 3D tissue cultures address many of the shortcomings of 2D cultures by more closely replicating the tumour microenvironment through a combination of realistic drug diffusion, paracrine signaling, cellular phenotype, and vascularization that can better mimic native human tissue. This review will discuss the common forms of 3D cell culture, including cell spheroids, organoids, organs-on-a-chip, and 3D bioprinted tissues. Their advantages and limitations will be presented, aiming to discuss the use of these 3D models to accurately represent human tissue and as an alternative to animal testing. The use of 3D culture platforms for preclinical drug development is expected to accelerate as these platforms continue to improve in complexity, reliability, and translational predictivity.

Lung cancer is the leading cause of global cancer-related mortality resulting in ~1.8 million deaths annually. Systemic, molecular targeted, and immune therapies have provided significant improvements of survival outcomes for patients. However, drug resistance usually arises and there is an urgent need for novel therapy screening and personalized medicine. 3D patient-derived organoid (PDO) models have emerged as a more effective and efficient alternative for ex vivo drug screening than 2D cell culture and patient-derived xenograft (PDX) models. In this review, we performed an extensive search of lung cancer PDO-based ex vivo drug screening studies. Lung cancer PDOs were successfully established from fresh or biobanked sections/biopsy of lung tumors, PDXs, and pleural affusion. PDOs were subject to ex vivo drug screening with chemotherapy, targeted therapy and immune therapy agents. PDOs mainly recapitulated the genomic alterations, transcriptomic landscape and drug sensitivity of primary tumors. Although sample sizes of the previous studies were limited and some technical challenges remained, PDOs showed promise to screen novel therapy drugs. With the technical advance of high throughput, tumor-on-chip, combined microenvironment, and air-liquid interface (ALI), the drug screening using PDOs would serve better for precision care of lung cancer patients.

Recent advancements in vascular organoid (VO) and vessel-on-chip (VoC) technologies have revolutionized our approach to studying cardiovascular diseases (CVDs), offering unprecedented insights through more physiologically relevant models. VOs generated from human pluripotent stem cells exhibit remarkable self-organization capabilities, forming complex three-dimensional structures that closely mimic human blood vessel architecture and function, while VoCs engineered with groundbreaking microfluidic systems that meticulously recreate the physical and functional attributes of blood vessels. These innovative constructs serve as powerful tools for investigating vascular development, disease progression, and therapeutic efficacy. By enabling the creation of patient-specific VOs and VoCs, they pave the way for personalized medicine approaches, allowing researchers to delve into genetic variations, intricate cellular interactions, and dynamic processes with exceptional resolution. The synergy between VOs and VoCs with cutting-edge technologies such as single-cell sequencing and high-resolution imaging has further amplified their potential, unveiling novel mechanisms underlying CVDs and identifying promising therapeutic targets. Herein, we summarize different types of VOs and VoCs and present an extensive overview on the generation and applications of VOs and VoCs in CVDs. We will also highlight clinical and translational challenges and future perspectives around VOs and VoCs.

The tumor organoid (tumoroid) model in three-dimensional (3D) culture systems has been developed to reflect more closely the in vivo tumors than 2D-cultured tumor cells. Notably, extracellular vesicles (EVs) are efficiently collectible from the culture supernatant of gel-free tumoroids. Matrix metalloproteinase (MMP) 3 is a multi-functional factor playing crucial roles in tumor progression. However, roles of MMP3 within tumor growth and EVs have not unveiled. Here, we investigated the protumorigenic roles of MMP3 on integrities of tumoroids and EVs. We generated MMP3-knockout (KO) cells using the CRISPR/Cas9 system from rapidly metastatic LuM1 tumor cells. Moreover, we established fluorescent cell lines with palmitoylation signal-fused fluorescent proteins (tdTomato and enhanced GFP). Then we confirmed the exchange of EVs between cellular populations and tumoroids. LuM1-tumoroids released large EVs (300-1000 nm) and small EVs (50-200 nm) while the knockout of MMP3 resulted in the additional release of broken EVs from tumoroids. The loss of MMP3 leads to a significant reduction in tumoroid size and to the development of the necrotic area within tumoroids. MMP3 and CD9 (a category-1 EV marker tetraspanin protein) were significantly down-regulated in MMP3-KO cells and their EV fraction. These weakened phenotypes by MMP3 KO were markedly rescued by the addition of MMP3-rich EVs or conditioned medium (CM) collected from LuM1-tumoroids, which caused a dramatic rise in the expression of MMP3, CD9, and Ki-67 (a marker of proliferating cells) in the MMP3-null/CD9-low tumoroids. Notably, MMP3 enriched in tumoroids-derived EVs and CM deeply penetrated into recipient MMP3-KO tumoroids, resulting in a remarkable enlargement of solid tumoroids, while MMP3-null EVs did not. These data demonstrate that EVs can mediate molecular transfer of MMP3 resulting in increasing the proliferation and CD9+ tumorigenesis, indicating crucial roles of MMP3 in tumor progression.

Despite improvements in participation in population-based screening programs, colorectal cancer remains a major cause of cancer-related mortality worldwide. Targeted interventions are desirable to reduce the health and economic burden of this disease. Two-dimensional monolayers of colorectal cancer cell lines represent the traditional in vitro models for disease and are often used for diverse purposes, including delineation of molecular pathways associated with disease aetiology or to gauge drug efficacy. The lack of complexity in such models, chiefly the limited epithelial cell diversity and differentiation, attenuated mucus production, lack of microbial interactions and mechanical stresses, has driven interest in development of more holistic and physiologically relevant in vitro model systems. In particular, established ex vivo patient-derived explant and patient-derived tumour xenograft models have been supplemented by progress in organoid and microfluidic organ-on-a-chip cultures. Here we discuss the applicability of advanced culturing technologies, such as organoid systems, as models for colorectal cancer and for testing chemotherapeutic drug sensitivity and efficacy. We highlight current challenges associated with organoid technologies and discuss their future for more accurate disease modelling and personalized medicine.

Alzheimer’s disease (AD), the most common cause of dementia, is characterized by disruptions in memory, cognition, and personality, significantly impacting morbidity and mortality rates among older adults. However, the exact pathophysiological mechanism of AD remains unknown, and effective treatment options for AD are still lacking. Human induced pluripotent stem cells (iPSC) are emerging as promising platforms for disease research, offering the ability to model genetic mutations associated with various conditions. Patient-derived iPSCs are useful for modeling neurodegenerative and neurodevelopmental disorders. In this study, we generated AD iPSCs from peripheral blood mononuclear cells obtained from a 65-year-old patient with AD carrying the E682K mutation in the amyloid precursor protein (APP) gene. Cerebral organoids derived from AD iPSCs recapitulated the AD phenotype, exhibiting significantly increased levels of tau protein. Our analysis revealed that an iPSC disease model of AD is a valuable assessment tool for pathophysiological research and drug screening.

Excess consumption of a high-fat diet has been identified as one of the contributing factors for obesity. Women are at higher risk for adult obesity than men, predisposing them to a different set of detrimental disease conditions. Furthermore, aging studies show that physiological decline also has a serious impact on changes in the endocrine properties of white adipose tissue. Howev-er, there is still relatively little known about the factors associated with obesity and aging and their compounding impact on women’s health. To investigate adipocytokine secretion profile changes, female C3H/HeJ mice were induced to obesity through long-term consumption of a high-fat diet. Weight gain measurements and Echo MRI analysis of fat composition showed in-creases were a due solely to the high fat content in the diet. Adipocytokine secretions were ana-lyzed in media conditioned from harvested visceral fat tissue that was organ cultured ex-vivo. Adipocytokine analysis across diets and age showed significant increases in Adiponectin and Leptin secretion in high-fat diets, accelerated increases in Resistin secretion with high-fat diets. Aging induced increased secretion of Lipcalin-2, Pentraxin-3 and Serpin E1, MCP-1 and ICAM-1, regardless of diet. Furthermore, comparisons of organoid cultured protein secretions and flash-frozen tissue samples differed greatly, suggesting the WAT organoid cultures may yield information more reflective of in situ conditions. Taken together, our results show that diet and aging significantly impact secretions from adipose tissue, that may contribute to women’s health issues.

Researchers in different disciplines studied liver’s genetic expression of organogenesis in embryogenesis; however, organogenesis has not been studied as an independent and a complementary process during adult liver regeneration. This paper reviewed studies and extracted information related to organogenesis in adult liver regeneration because of organogenesis’ important role in cancer and tissue regeneration.

Late-stage epithelial ovarian cancer (EOC) involves widespread dissemination of malignant disease throughout the peritoneal cavity, often accompanied by ascites. EOC metastasis relies on the formation of multicellular aggregates, called spheroids. Given that Liver Kinase B1 (LKB1) is required for EOC spheroid viability and LKB1 loss in EOC cells decreases tumor burden in mice, we investigated whether the LKB1 complex controls invasive properties of human EOC spheroids. LKB1 signalling was antagonized through CRISPR/Cas9 genetic knockout of LKB1 and/or RNAi-dependent targeting of STE20-related kinase adaptor protein (STRAD; an LKB1 activator). EOC spheroids expressing nuclear GFP (green) or mKate2 (red) constructs were embedded in Matrigel for real-time live-cell invasion monitoring. Migration and invasion were also assessed in spheroid culture using Transwell chambers, spheroid reattachment, and mesothelial clearance assays. The loss of LKB1 and STRAD signalling decreased cell invasion through Matrigel and Transwell membranes, as well as mesothelial cell clearance. In the absence of LKB1, zymographic assays identified a loss of matrix metalloproteinase (MMP) activity, whereas spheroid reattachment assays found that coating plates with fibronectin restored the invasive potential. A three-dimensional EOC organoid model demonstrated that organoid area was greatly reduced by LKB1 loss. Overall, our data indicated that LKB1 and STRAD facilitated EOC metastasis by promoting MMP activity and fibronectin expression. Given that LKB1 and STRAD are crucial for EOC metastasis, targeting LKB1 and/or STRAD could disrupt the dissemination of EOC, making inhibitors of the LKB1 pathway an alternative therapeutic strategy for EOC patients.

Researchers have developed and used several three-dimensional (3D) culture systems, including spheroids, organoids, and tumoroids. Drug resistance is a crucial issue involving recurrence in cancer patients. Many studies on anticancer drugs have been done in 2D culture systems, where-as 3D cultured tumoroids have many advantages for assessing drug sensitivity and resistance. Here, we aim to investigate whether Cisplatin (a DNA crosslinker), Imatinib (a multiple tyro-sine kinase inhibitor), and 5-Fluorouracil (5-FU: an antimetabolite) alter tumoroid growth of metastatic colorectal cancer (mCRC). To establish a liquid-based 3D multiplexing reporter assay system, LuM1 (a murine mCRC cell line) was stably transfected with the Mmp9 promoter-driven ZsGreen reporter gene, which was designated as LuM1/m9 cells and cultured in NanoCulture Plate (NCP), a 3D culture device. The larger tumoroids were not sensitive to Cisplatin and ex-pressed ABCG2 (a marker of cancer stem cells, a.k.a. a drug efflux transporter), whereas smaller cell-aggregates were more sensitive to Cisplatin. Both Imatinib and Cisplatin significantly in-creased tumoroid growth (larger than 300 μm2) and Mmp9 promoter activity and were not cytotoxic to the mCRC tumoroids. On the other hand, 5-FU was cytotoxic to the tumoroids and significantly inhibited tumoroid growth, although not completely. Thus, platinum resistance and imatinib resistance in mCRC were modeled using the liquid-based 3D cultured tumoroid system. The tumoroid culture is useful and easily accessible for the assessment of drug sensitivity and resistance.