Organoid culture containing cancer cells and stromal cells reveals that podoplanin-positive cancer-associated fibroblasts enhance proliferation of lung cancer cells

New insights into cancer pathology learned from the dynamics of cancer-associated fibroblasts

Paget's "Seed and Soil" theory, proposed in 1889, emphasizes the importance of the microenvironment where cancer cells grow in metastatic sites. Over a century later, this concept remains a cornerstone in comprehending cancer biology and devising treatment strategies. The "Seed and Soil" theory, which initially explained how cancer spreads to distant organs, now also applies to the tumor microenvironment (TME) within primary tumors. This theory emphasizes the critical interaction between cancer cells ("seeds") and their surrounding environment ("soil") and how this interaction affects both tumor progression within the primary site and at metastatic sites. An important point to note is that the characteristics of the TME are not static but dynamic, undergoing substantial changes during tumor progression and after treatment with therapeutic drugs. Cancer-associated fibroblasts (CAFs), recognized as the principal noncancerous cellular component within the TME, play multifaceted roles in tumor progression including promoting angiogenesis, remodeling the extracellular matrix, and regulating immune responses. In this comprehensive review, we focus on the findings regarding how the dynamics of CAFs contribute to cancer progression and drug sensitivity. Understanding the dynamics of CAFs could provide new insights into cancer pathology and lead to important advancements in cancer research and treatment.

A patient-specific lung cancer assembloid model with heterogeneous tumor microenvironments

Cancer models play critical roles in basic cancer research and precision medicine. However, current in vitro cancer models are limited by their inability to mimic the three-dimensional architecture and heterogeneous tumor microenvironments (TME) of in vivo tumors. Here, we develop an innovative patient-specific lung cancer assembloid (LCA) model by using droplet microfluidic technology based on a microinjection strategy. This method enables precise manipulation of clinical microsamples and rapid generation of LCAs with good intra-batch consistency in size and cell composition by evenly encapsulating patient tumor-derived TME cells and lung cancer organoids inside microgels. LCAs recapitulate the inter- and intratumoral heterogeneity, TME cellular diversity, and genomic and transcriptomic landscape of their parental tumors. LCA model could reconstruct the functional heterogeneity of cancer-associated fibroblasts and reflect the influence of TME on drug responses compared to cancer organoids. Notably, LCAs accurately replicate the clinical outcomes of patients, suggesting the potential of the LCA model to predict personalized treatments. Collectively, our studies provide a valuable method for precisely fabricating cancer assembloids and a promising LCA model for cancer research and personalized medicine.

Engineered 3D ex vivo models to recapitulate the complex stromal and immune interactions within the tumor microenvironment

Cancer thrives in a complex environment where interactions between cellular and acellular components, surrounding the tumor, play a crucial role in disease development and progression. Despite significant progress in cancer research, the mechanism driving tumor growth and therapeutic outcomes remains elusive. Two-dimensional (2D) cell culture assays and in vivo animal models are commonly used in cancer research and therapeutic testing. However, these models suffer from numerous shortcomings including lack of key features of the tumor microenvironment (TME) & cellular composition, cost, and ethical clearance. To that end, there is an increased interest in incorporating and elucidating the influence of TME on cancer progression. Advancements in 3D-engineered ex vivo models, leveraging biomaterials and microengineering technologies, have provided an unprecedented ability to reconstruct native-like bioengineered cancer models to study the heterotypic interactions of TME with a spatiotemporal organization. These bioengineered cancer models have shown excellent capabilities to bridge the gap between oversimplified 2D systems and animal models. In this review article, we primarily provide an overview of the immune and stromal cellular components of the TME and then discuss the latest state-of-the-art 3D-engineered ex vivo platforms aiming to recapitulate the complex TME features. The engineered TME model, discussed herein, are categorized into three main sections according to the cellular interactions within TME: (i) Tumor-Stromal interactions, (ii) Tumor-Immune interactions, and (iii) Complex TME interactions. Finally, we will conclude the article with a perspective on how these models can be instrumental for cancer translational studies and therapeutic testing.

Bioengineered hydrogels enhance ex vivo preservation of patient-derived tumor explants for drug evaluation

Ex vivo patient-derived tumor slices (PDTS) are currently limited by short-term viability in culture. Here, we show how bioengineered hydrogels enable the identification of key matrix parameters that significantly enhance PDTS viability compared to conventional culture systems. As demonstrated using single-cell RNA sequencing and high-dimensional flow cytometry, hydrogel-embedded PDTS tightly preserved cancer, cancer-associated fibroblast, and various immune cell populations and subpopulations in the corresponding original tumor. Cell-cell communication networks within the tumor microenvironment, including immune checkpoint ligand-receptor interactions, were also maintained. Remarkably, our results from a co-clinical trial suggest hydrogel-embedded PDTS may predict sensitivity to immune checkpoint inhibitors (ICIs) in head and neck cancer patients. Further, we show how these longer term-cultured tumor explants uniquely enable the sampling and detection of temporal evolution in molecular readouts when treated with ICIs. By preserving the compositional heterogeneity and complexity of patient tumors, hydrogel-embedded PDTS provide a valuable tool to facilitate experiments targeting the tumor microenvironment.

Patient-derived organoids in human cancer: a platform for fundamental research and precision medicine

Cancer is associated with a high degree of heterogeneity, encompassing both inter- and intra-tumor heterogeneity, along with considerable variability in clinical response to common treatments across patients. Conventional models for tumor research, such as in vitro cell cultures and in vivo animal models, demonstrate significant limitations that fall short of satisfying the research requisites. Patient-derived tumor organoids, which recapitulate the structures, specific functions, molecular characteristics, genomics alterations and expression profiles of primary tumors. They have been efficaciously implemented in illness portrayal, mechanism exploration, high-throughput drug screening and assessment, discovery of innovative therapeutic targets and potential compounds, and customized treatment regimen for cancer patients. In contrast to conventional models, tumor organoids offer an intuitive, dependable, and efficient in vitro research model by conserving the phenotypic, genetic diversity, and mutational attributes of the originating tumor. Nevertheless, the organoid technology also confronts the bottlenecks and challenges, such as how to comprehensively reflect intra-tumor heterogeneity, tumor microenvironment, tumor angiogenesis, reduce research costs, and establish standardized construction processes while retaining reliability. This review extensively examines the use of tumor organoid techniques in fundamental research and precision medicine. It emphasizes the importance of patient-derived tumor organoid biobanks for drug development, screening, safety evaluation, and personalized medicine. Additionally, it evaluates the application of organoid technology as an experimental tumor model to better understand the molecular mechanisms of tumor. The intent of this review is to explicate the significance of tumor organoids in cancer research and to present new avenues for the future of tumor research.

Advanced lung organoids and lung-on-a-chip for cancer research and drug evaluation: a review

Lung cancer has become the primary cause of cancer-related deaths because of its high recurrence rate, ability to metastasise easily, and propensity to develop drug resistance. The wide-ranging heterogeneity of lung cancer subtypes increases the complexity of developing effective therapeutic interventions. Therefore, personalised diagnostic and treatment strategies are required to guide clinical practice. The advent of innovative three-dimensional (3D) culture systems such as organoid and organ-on-a-chip models provides opportunities to address these challenges and revolutionise lung cancer research and drug evaluation. In this review, we introduce the advancements in lung-related 3D culture systems, with a particular focus on lung organoids and lung-on-a-chip, and their latest contributions to lung cancer research and drug evaluation. These developments include various aspects, from authentic simulations and mechanistic enquiries into lung cancer to assessing chemotherapeutic agents and targeted therapeutic interventions. The new 3D culture system can mimic the pathological and physiological microenvironment of the lung, enabling it to supplement or replace existing two-dimensional culture models and animal experimental models and realize the potential for personalised lung cancer treatment.

Biophysics in tumor growth and progression: from single mechano-sensitive molecules to mechanomedicine

Evidence from physical sciences in oncology increasingly suggests that the interplay between the biophysical tumor microenvironment and genetic regulation has significant impact on tumor progression. Especially, tumor cells and the associated stromal cells not only alter their own cytoskeleton and physical properties but also remodel the microenvironment with anomalous physical properties. Together, these altered mechano-omics of tumor tissues and their constituents fundamentally shift the mechanotransduction paradigms in tumorous and stromal cells and activate oncogenic signaling within the neoplastic niche to facilitate tumor progression. However, current findings on tumor biophysics are limited, scattered, and often contradictory in multiple contexts. Systematic understanding of how biophysical cues influence tumor pathophysiology is still lacking. This review discusses recent different schools of findings in tumor biophysics that have arisen from multi-scale mechanobiology and the cutting-edge technologies. These findings range from the molecular and cellular to the whole tissue level and feature functional crosstalk between mechanotransduction and oncogenic signaling. We highlight the potential of these anomalous physical alterations as new therapeutic targets for cancer mechanomedicine. This framework reconciles opposing opinions in the field, proposes new directions for future cancer research, and conceptualizes novel mechanomedicine landscape to overcome the inherent shortcomings of conventional cancer diagnosis and therapies.

A novel ex vivo lung cancer model based on bioengineered rat lungs

Introduction: Two-dimensional cell cultures have contributed substantially to lung cancer research, but 3D cultures are gaining attention as a new, more efficient, and effective research model. A model reproducing the 3D characteristics and tumor microenvironment of the lungs in vivo, including the co-existence of healthy alveolar cells with lung cancer cells, is ideal. Here, we describe the creation of a successful ex vivo lung cancer model based on bioengineered lungs formed by decellularization and recellularization. Methods: Human cancer cells were directly implanted into a bioengineered rat lung, which was created with a decellularized rat lung scaffold reseeded with epithelial cells, endothelial cells and adipose-derived stem cells. Four human lung cancer cell lines (A549, PC-9, H1299, and PC-6) were applied to demonstrate forming cancer nodules on recellularized lungs and histopathological assessment were made among these models. MUC-1 expression analysis, RNA-seq analysis and drug response test were performed to demonstrate the superiority of this cancer model. Results: The morphology and MUC-1 expression of the model were like those of lung cancer in vivo. RNA sequencing revealed an elevated expression of genes related to epithelial-mesenchymal transition, hypoxia, and TNF-α signaling via NF-κB; but suppression of cell cycle-related genes including E2F. Drug response assays showed that gefitinib suppressed PC-9 cell proliferation equally well in the 3D lung cancer model as in 2D culture dishes, albeit over a smaller volume of cells, suggesting that fluctuations in gefitinib resistance genes such as JUN may affect drug sensitivity. Conclusions: A novel ex vivo lung cancer model was closely reproduced the 3D structure and microenvironment of the actual lungs, highlighting its possible use as a platform for lung cancer research and pathophysiological studies.

Periostin secreted from podoplanin-positive cancer-associated fibroblasts promotes metastasis of gastric cancer by regulating cancer stem cells via AKT and YAP signaling pathway

Cancer-associated fibroblasts (CAFs) are heterogeneous stromal cells present in the tumor microenvironment (TME), which play a critical role in gastric cancer (GC) progression. Here, we examined a subset of CAFs with high podoplanin (PDPN) expression, which is correlated with tumor metastasis and poor survival in GC patients. Animal models of gastric cancer liver metastasis monitored by micro-PET/CT confirmed that periostin (POSTN) derived from PDPN(+) CAFs regulated CAFs' pro-migratory ability. Mechanistically, PDPN(+) CAFs secreted POSTN to modulate cancer stem cells (CSCs) through FAK/AKT phosphorylation. Furthermore, POSTN could also activate FAK/YAP signaling in GC cells to produce increased amounts of IL-6, which in turn induced phosphorylation of PI3K/AKT in PDPN(+) CAFs. Prolonged PI3K/AKT pathway activation in PDPN(+) CAFs maintains the production of POSTN and the effect on CSC enrichment and GC cell migration. In conclusion, our study demonstrated a positive feedback loop between PDPN(+) CAFs and CSCs during GC progression and suggested a selective target for GC treatment.

Key aspects for conception and construction of co-culture models of tumor-stroma interactions

The tumor microenvironment is crucial in the initiation and progression of cancers. The interplay between cancer cells and the surrounding stroma shapes the tumor biology and dictates the response to cancer therapies. Consequently, a better understanding of the interactions between cancer cells and different components of the tumor microenvironment will drive progress in developing novel, effective, treatment strategies. Co-cultures can be used to study various aspects of these interactions in detail. This includes studies of paracrine relationships between cancer cells and stromal cells such as fibroblasts, endothelial cells, and immune cells, as well as the influence of physical and mechanical interactions with the extracellular matrix of the tumor microenvironment. The development of novel co-culture models to study the tumor microenvironment has progressed rapidly over recent years. Many of these models have already been shown to be powerful tools for further understanding of the pathophysiological role of the stroma and provide mechanistic insights into tumor-stromal interactions. Here we give a structured overview of different co-culture models that have been established to study tumor-stromal interactions and what we have learnt from these models. We also introduce a set of guidelines for generating and reporting co-culture experiments to facilitate experimental robustness and reproducibility.

Advances in Tumor Organoids for the Evaluation of Drugs: A Bibliographic Review

Tumor organoids are defined as self-organized three-dimensional assemblies of heterogeneous cell types derived from patient samples that mimic the key histopathological, genetic, and phenotypic characteristics of the original tumor. This technology is proposed as an ideal candidate for the evaluation of possible therapies against cancer, presenting advantages over other models which are currently used. However, there are no reports in the literature that relate the techniques and material development of tumor organoids or that emphasize in the physicochemical and biological properties of materials that intent to biomimicry the tumor extracellular matrix. There is also little information regarding the tools to identify the correspondence of native tumors and tumoral organoids (tumoroids). Moreover, this paper relates the advantages of organoids compared to other models for drug evaluation. A growing interest in tumoral organoids has arisen from 2009 to the present, aimed at standardizing the process of obtaining organoids, which more accurately resemble patient-derived tumor tissue. Likewise, it was found that the characteristics to consider for the development of organoids, and therapeutic responses of them, are cell morphology, physiology, the interaction between cells, the composition of the cellular matrix, and the genetic, phenotypic, and epigenetic characteristics. Currently, organoids have been used for the evaluation of drugs for brain, lung, and colon tumors, among others. In the future, tumor organoids will become closer to being considered a better model for studying cancer in clinical practice, as they can accurately mimic the characteristics of tumors, in turn ensuring that the therapeutic response aligns with the clinical response of patients.

Organoids for Modeling (Colorectal) Cancer in a Dish

Simple Summary

Despite remarkable progress in the treatment of cancer patients, the medical need for drugs with better efficacy is still unmet and high. In addition to accurate prediction of drug efficacy for individual patients, pathophysiologically relevant preclinical model systems with increased predictive power are urgently needed to reduce the high rate of clinical trial failure in oncology. Organoids grown from patient material represent exceptionally valuable model systems to mimic and study human diseased tissues such as tumors. Here, we elaborate an overview of innovative and advanced organoid model systems and highlight the exciting opportunities of organoids for personalized precision medicine and the field of immuno-oncology drug development.

Abstract

Functional studies of primary cancer have been limited to animal models for a long time making it difficult to study aspects specific to human cancer biology. The development of organoid technology enabled us to culture human healthy and tumor cells as three-dimensional self-organizing structures in vitro for a prolonged time. Organoid cultures conserve the heterogeneity of the originating epithelium regarding cell types and tumor clonality. Therefore, organoids are considered an invaluable tool to study and genetically dissect various aspects of human cancer biology. In this review, we describe the applications, advantages, and limitations of organoids as human cancer models with the main emphasis on colorectal cancer.

Cancer-associated fibroblasts in nonsmall cell lung cancer: From molecular mechanisms to clinical implications

Lung cancer is the common and leading cause of cancer death worldwide. The tumor microenvironment has been recognized to be instrumental in tumorigenesis. To have a deep understanding of the molecular mechanism of nonsmall cell lung carcinoma (NSCLC), cancer-associated fibroblasts (CAFs) have gained increasing research interests. CAFs belong to the crucial and dominant cell population in the tumor microenvironment to support the cancer cells. The interplay and partnership between cancer cells and CAFs contribute to each stage of tumorigenesis. CAFs exhibit prominent heterogeneity and secrete different kinds of cytokines and chemokines, growth factors and extracellular matrix proteins involved in cancer cell proliferation, invasion, metastasis and chemoresistance. Many studies focused on the protumorigenic functions of CAFs, yet many challenges about the heterogeneity of CAFS remain unresolved. This review comprehensively summarized the tumor-promoting role and molecular mechanisms of CAFs in NSCLC, including their origin, phenotypic changes and heterogeneity and their functional roles in carcinogenesis. Meanwhile, we also highlighted the updated molecular classifications based on the molecular features and functional roles of CAFs. With the development of cutting-edge platforms and further investigations of CAFs, novel therapeutic strategies for accurately targeting CAFs in NSCLC may be developed based on the increased understanding of the relevant molecular mechanisms.

Multiple Cell Cultures for MRI Analysis

Magnetic resonance imaging (MRI) is an imaging method that enables diagnostics. In recent years, this technique has been widely used for research using cell cultures used in pharmaceutical science to understand the distribution of various drugs in a variety of biological samples, from cellular models to tissues. MRI's dynamic development in recent years, in addition to diagnostics, has allowed the method to be implemented to assess response to applied therapies. Conventional MRI imaging provides anatomical and pathological information. Due to advanced technology, MRI provides physiological information. The use of cell cultures is very important in the process of testing new synthesized drugs, cancer research, and stem cell research, among others. Two-dimensional (2D) cell cultures conducted under laboratory conditions, although they provide a lot of information, do not reflect the basic characteristics of the tumor. To replicate the tumor microenvironment in science, a three-dimensional (3D) culture of tumor cells was developed. This makes it possible to reproduce in vivo conditions where, in addition, there is a complex and dynamic process of cell-to-cell communication and cell-matrix interaction. In this work, we reviewed current research in 2D and 3D cultures and their use in MRI studies. Articles for each section were collected from PubMed, ScienceDirect, Web of Science, and Google Scholar.

Organoids in lung cancer: A teenager with infinite growth potential

Despite the rapid advancement in lung cancer research, morbidity and mortality remain high in recent years. Therefore, deeper learning of the underlying molecular mechanisms of pathogenesis and discovery of novel effective therapeutic strategies of treatment in lung cancer research are around the corner. Among these, applying an efficient and reliable preclinical model would be a critical step that exists throughout the whole process. Traditional 2D models used in lung cancer research, including lung cancer cell lines and cell-derived xenograft models, cannot recapitulate the situations of patients due to the lack of a tumor microenvironment or tumor heterogeneity. Organoids, newly developed 3D in vitro structures, more comprehensively imitate the architecture, interaction and genetics of human organs. Cancer organoids, especially those derived from individual patients, can better resemble primary tumor tissues and thus have a greater potential for making breakthroughs in future cancer studies. Here, we mainly review recent advances in the methodologies and applications of lung cancer organoids, which are just developing but have huge potential.

Neoplastic synovial lining cells that coexpress podoplanin and CD90 overproduce CSF-1, driving tenosynovial giant cell tumor

Tenosynovial giant cell tumor (TCGT) is a rare neoplasm affecting the synovium of joints, bursae, and tendon sheaths. The overproduction of colony-stimulating factor-1 (CSF-1) by a minority of the tumor population works in a paracrine fashion to drive tumor growth. Pathology of the reactive, monocytic component has been well elucidated, whereas the populations of neoplastic cells and all the sources of CSF-1 overproduction are incompletely characterized. Podoplanin (PDPN), or gp38, is a cell surface glycoprotein that is expressed on fibroblast-like synovial cells and upregulated in rheumatoid arthritis and many cancers; it governs cell mobility, epithelial-mesenchymal transition, and other functions and is associated with lymphangiogenesis and poor prognosis in many solid tumors, which underscores its local and possible systemic effects. We found higher PDPN expression in TGCT than in internal controls of patients' healthy synovium. Flow cytometry partitioned PDPN^high cells into PDPN^high CD90⁺ and PDPN^high CD14⁺ populations. Quantitative real-time polymerase chain reaction analysis of the PDPN^high CD90⁺ cells revealed that CSF-1 expression was 10-fold higher than in PDPN^high CD14⁺ cells. Therefore, we conclude that the lining fibroblast-like synovial cells, which express PDPN^high CD90⁺ , are responsible for the overproduction of CSF-1 and for driving tumor growth.

Lung Cancer Organoids: The Rough Path to Personalized Medicine

Simple Summary

Lung cancer is very difficult to cure, especially when it has spread to other parts of the body. One of the main reasons that delay the identification of effective therapies is the complexity of lung cancer cells, which can be very different among individual patients. Organoids are small aggregates of tumor cells that are generated from lung tumors and used in cancer research laboratories to study the features of tumor cells. Organoids have unique properties, as they reproduce many characteristics of the tumor derived from each specific patient. Due to their capacity to reproduce individual tumor features in the laboratory setting, organoids are an excellent system to study lung cancer and to identify functional therapies. This review summarizes the challenges encountered by researchers in the field of lung cancer organoids and describes how the advances in organoid technology may allow the future development of individualized therapies for lung cancer patients.

Abstract

Lung cancer is the leading cause of cancer death worldwide. Despite significant advances in research and therapy, a dismal 5-year survival rate of only 10–20% urges the development of reliable preclinical models and effective therapeutic tools. Lung cancer is characterized by a high degree of heterogeneity in its histology, a genomic landscape, and response to therapies that has been traditionally difficult to reproduce in preclinical models. However, the advent of three-dimensional culture technologies has opened new perspectives to recapitulate in vitro individualized tumor features and to anticipate treatment efficacy. The generation of lung cancer organoids (LCOs) has encountered greater challenges as compared to organoids derived from other tumors. In the last two years, many efforts have been dedicated to optimizing LCO-based platforms, resulting in improved rates of LCO production, purity, culture timing, and long-term expansion. However, due to the complexity of lung cancer, further advances are required in order to meet clinical needs. Here, we discuss the evolution of LCO technology and the use of LCOs in basic and translational lung cancer research. Although the field of LCOs is still in its infancy, its prospective development will likely lead to new strategies for drug testing and biomarker identification, thus allowing a more personalized therapeutic approach for lung cancer patients.

Tumor organoids: applications in cancer modeling and potentials in precision medicine

Cancer is a top-ranked life-threatening disease with intratumor heterogeneity. Tumor heterogeneity is associated with metastasis, relapse, and therapy resistance. These factors contribute to treatment failure and an unfavorable prognosis. Personalized tumor models faithfully capturing the tumor heterogeneity of individual patients are urgently needed for precision medicine. Advances in stem cell culture have given rise to powerful organoid technology for the generation of in vitro three-dimensional tissues that have been shown to more accurately recapitulate the structures, specific functions, molecular characteristics, genomic alterations, expression profiles, and tumor microenvironment of primary tumors. Tumoroids in vitro serve as an important component of the pipeline for the discovery of potential therapeutic targets and the identification of novel compounds. In this review, we will summarize recent advances in tumoroid cultures as an excellent tool for accurate cancer modeling. Additionally, vascularization and immune microenvironment modeling based on organoid technology will also be described. Furthermore, we will summarize the great potential of tumor organoids in predicting the therapeutic response, investigating resistance-related mechanisms, optimizing treatment strategies, and exploring potential therapies. In addition, the bottlenecks and challenges of current tumoroids will also be discussed in this review.

The Patient-Derived Cancer Organoids: Promises and Challenges as Platforms for Cancer Discovery

The cancer burden is rapidly increasing in most countries, and thus, new anticancer drugs for effective cancer therapy must be developed. Cancer model systems that recapitulate the biological processes of human cancers are one of the cores of the drug development process. PDCO has emerged as a unique model that preserves the genetic, physiological, and histologic characteristics of original cancer, including inter- and intratumoral heterogeneities. Due to these advantages, the PCDO model is increasingly investigated for anticancer drug screening and efficacy testing, preclinical patient stratification, and precision medicine for selecting the most effective anticancer therapy for patients. Here, we review the prospects and limitations of PDCO compared to the conventional cancer models. With advances in culture success rates, co-culture systems with the tumor microenvironment, organoid-on-a-chip technology, and automation technology, PDCO will become the most promising model to develop anticancer drugs and precision medicine.

Scientific Validation and Clinical Application of Lung Cancer Organoids

Lung cancer organoid (LCO) is a novel model of lung cancer that facilitates drug screening. However, the success rate of LCOs varies from 7% to 87%, and the culture medium compositions are markedly different. Airway organoid media can be used for LCO cultures, but this promotes the overgrowth of normal cell organoids especially in LCOs from intrapulmonary lesions. Several modified media are specifically utilized for promoting the cancer cell's growth. For culturing high-purity LCOs, cancer cells from metastatic lesions and malignant effusions are used. Recently, single-cell RNA sequencing has identified previously unknown cell populations in the lungs and lung cancer. This sequencing technology can be used to validate whether the LCO recapitulates the heterogeneity and functional hierarchy of the primary tumor. Several groups have attempted to culture LCOs with mesenchymal cells and immune cells to recapitulate the tumor microenvironment. Disease modeling using LCO provides novel insight into the pathophysiology of lung cancer and enables high-throughput screening for drug discovery and prognosis prediction. An LCO model would help to identify new concepts as a basis for lung cancer targeting by discovering innovative therapeutic targets.

Tumor organoids: synergistic applications, current challenges, and future prospects in cancer therapy

Patient-derived cancer cells (PDCs) and patient-derived xenografts (PDXs) are often used as tumor models, but have many shortcomings. PDCs not only lack diversity in terms of cell type, spatial organization, and microenvironment but also have adverse effects in stem cell cultures, whereas PDX are expensive with a low transplantation success rate and require a long culture time. In recent years, advances in three-dimensional (3D) organoid culture technology have led to the development of novel physiological systems that model the tissues of origin more precisely than traditional culture methods. Patient-derived cancer organoids bridge the conventional gaps in PDC and PDX models and closely reflect the pathophysiological features of natural tumorigenesis and metastasis, and have led to new patient-specific drug screening techniques, development of individualized treatment regimens, and discovery of prognostic biomarkers and mechanisms of resistance. Synergistic combinations of cancer organoids with other technologies, for example, organ-on-a-chip, 3D bio-printing, and CRISPR-Cas9-mediated homology-independent organoid transgenesis, and with treatments, such as immunotherapy, have been useful in overcoming their limitations and led to the development of more suitable model systems that recapitulate the complex stroma of cancer, inter-organ and intra-organ communications, and potentially multiorgan metastasis. In this review, we discuss various methods for the creation of organ-specific cancer organoids and summarize organ-specific advances and applications, synergistic technologies, and treatments as well as current limitations and future prospects for cancer organoids. Further advances will bring this novel 3D organoid culture technique closer to clinical practice in the future.

Polycaprolactone Electrospun Scaffolds Produce an Enrichment of Lung Cancer Stem Cells in Sensitive and Resistant EGFRm Lung Adenocarcinoma

Simple Summary

The culture of lung cancer stem cells (LCSCs) is not possible using traditional flat polystyrene surfaces. The study of these tumor-initiating cells is fundamental due to their key role in the resistance to anticancer therapies, tumor recurrence, and metastasis. Hence, we evaluated the use of polycaprolactone electrospun (PCL-ES) scaffolds for culturing LCSC population in sensitive and resistant EGFR-mutated lung adenocarcinoma models. Our findings revealed that both cell models seeded on PCL-ES structures showed a higher drug resistance, enhanced levels of several genes and proteins related to epithelial-to-mesenchymal process, stemness, and surface markers, and the activation of the Hedgehog pathway. We also determined that the non-expression of CD133 was associated with a low degree of histological differentiation, disease progression, distant metastasis, and worse overall survival in EGFR-mutated non-small cell lung cancer patients. Therefore, we confirmed PCL-ES scaffolds as a suitable three-dimensional cell culture model for the study of LCSC niche.

Abstract

The establishment of a three-dimensional (3D) cell culture model for lung cancer stem cells (LCSCs) is needed because the study of these stem cells is unable to be done using flat surfaces. The study of LCSCs is fundamental due to their key role in drug resistance, tumor recurrence, and metastasis. Hence, the purpose of this work is the evaluation of polycaprolactone electrospun (PCL-ES) scaffolds for culturing LCSCs in sensitive and resistant EGFR-mutated (EGFRm) lung adenocarcinoma cell models. We performed a thermal, physical, and biological characterization of 10% and 15%-PCL-ES structures. Several genes and proteins associated with LCSC features were analyzed by RT-qPCR and Western blot. Vimentin and CD133 tumor expression were evaluated in samples from 36 patients with EGFRm non-small cell lung cancer through immunohistochemistry. Our findings revealed that PC9 and PC9-GR3 models cultured on PCL-ES scaffolds showed higher resistance to osimertinib, upregulation of ABCB1, Vimentin, Snail, Twist, Sox2, Oct-4, and CD166, downregulation of E-cadherin and CD133, and the activation of Hedgehog pathway. Additionally, we determined that the non-expression of CD133 was significantly associated with a low degree of histological differentiation, disease progression, and distant metastasis. To sum up, we confirmed PCL-ES scaffolds as a suitable 3D cell culture model for the study of the LCSC niche.

Establishment and drug screening of patient-derived extrahepatic biliary tract carcinoma organoids

BACKGROUND

Patient-derived organoids (PDO) have been proposed as a novel in vitro method of drug screening for different types of cancer. However, to date, extrahepatic biliary tract carcinoma (eBTC) PDOs have not yet been fully established.

METHODS

We collected six samples of gallbladder carcinoma (GBC) and one sample of extrahepatic cholangiocarcinoma (eCCA) from seven patients to attempt to establish eBTC PDOs for drug screening. We successfully established five GBC and one eCCA PDOs. Histological staining was used to compare structural features between the original tissues and cancer PDOs. Whole exome sequencing (WES) was performed to analyze the genetic profiles of original tissues and cancer PDOs. Drug screening, including gemcitabine, 5-fluorouracil, cisplatin, paclitaxel, infigratinib, and ivosidenib, was measured and verified by clinical effects in certain cases.

RESULTS

Different PDOs exhibited diverse growth rates during in vitro culture. Hematoxylin and eosin staining demonstrated that the structures of most cancer PDOs retained the original structures of adenocarcinoma. Immunohistological and periodic acid-schiff staining revealed that marker expression in cancer PDOs was similar to that of the original specimens. Genetic profiles from the four original specimens, as well as paired cancer PDOs, were analyzed using whole exome sequencing. Three of the four PDOs exhibited a high degree of similarity when compared to the original specimens, except for GBC2 PDO, which only had a concordance of 74% in the proportion of single nucleotide polymorphisms in the coding sequence. In general, gemcitabine was found to be the most efficient drug for eBTC treatment, as it showed moderate or significant inhibitory impact on cancer growth. Results from drug screening were confirmed to a certain extent by three clinical cases.

CONCLUSIONS

Our study successfully established a series of eBTC PDOs, which contributed to the field of eBTC PDOs. Additional enhancements should be explored to improve the growth rate of PDOs and to preserve their immune microenvironment.

Prognostic Value of Podoplanin in Various Tumors

Background:

The prognostic significance of podoplanin (PDPN) in tumor cells for cancer patients’ survival remains controversial. Therefore, we performed this meta-analysis to clarify the relationship between the podoplanin-positive tumor cells and cancer prognosis.

Method:

Eligible studies were identified by searching the Pubmed and EBSCO online databases up to August 2019. Hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated to evaluate the correlation between podoplanin expression and overall survival (OS) and/or disease-free survival (DFS) and odds ratios (ORs) with 95% CIs severed as the summarized statistics for clinicopathological characteristic.

Results:

A total of 2155 patients from 21 eligible studies were included. The results revealed that high expression of podoplanin was associated with a poor survival rate in cancer patients. Further subgroup analysis stratified by tumor type showed that podoplanin-positive tumor cell infiltration had a negative prognostic effect associated with survival in esophageal cancer and oropharyngeal cancer. In addition, high expression of these cells was significantly associated with N stage, T stage, TNM stage and vascular invasion.

Conclusion:

Our study suggests the over-expression of podoplanin might be a significant prognostic indicator for patients with esophageal and oropharyngeal cancer.

Screening and Identification of Key Genes for Activation of Islet Stellate Cell

Background

It has been demonstrated that activated islet stellate cells (ISCs) play a critical role in islet fibrogenesis and significantly contribute to the progression of type 2 diabetes mellitus. However, the key molecules responsible for ISCs activation have not yet been determined. This study aimed to identify the potential key genes involved in diabetes-induced activation of ISCs.

Method

Stellate cells were isolated from three 10-week-old healthy male Wistar rats and three Goto-Kakizaki (GK) rats. Cells from each rat were primary cultured under the same condition. A Genome-wide transcriptional sequence of stellate cells was generated using the Hiseq3000 platform. The identified differentially expressed genes were validated using quantitative real-time PCR and western blotting in GK rats, high fat diet (HFD) rats, and their controls.

Results

A total of 204 differentially expressed genes (DEGs) between GK. ISCs and Wistar ISCs (W.ISCs) were identified, accounting for 0.58% of all the 35,362 genes detected. After the Gene Ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment analyses, the mRNA levels of these genes were further confirmed by real-time PCR in cultured ISCs. We then selected Fos, Pdpn, Bad as the potential key genes for diabetes-induced activation of ISCs. Finally, we confirmed the protein expression levels of FOS, podoplanin, and Bad by western blotting and immunofluorescence in GK rats, HFD rats, and their controls. The results showed that the expression level of FOS was significantly decreased, while podoplanin and Bad were significantly increased in GK.ISCs and HFD rats compared with controls, which were consistent with the expression of α-smooth muscle actin.

Conclusions

A total of 204 DEGs were found between the GK.ISCs and W.ISCs. After validating the expression of potential key genes from GK rats and HFD rats, Fos, Pdpn, and Bad might be potential key genes involved in diabetes-induced activation of ISCs.

In Vitro 3D Cultures to Model the Tumor Microenvironment

Simple Summary

Tumor stroma is known to significantly influence cancer initiation and progression. In the last decade, 3D cell cultures have shown potential in modeling the tumor microenvironment. This review summarizes the main features of current 3D models, shedding light on their importance in the study of cancer biology and treatment.

Abstract

It is now well established that the tumor microenvironment plays a key role in determining cancer growth, metastasis and drug resistance. Thus, it is fundamental to understand how cancer cells interact and communicate with their stroma and how this crosstalk regulates disease initiation and progression. In this setting, 3D cell cultures have gained a lot of interest in the last two decades, due to their ability to better recapitulate the complexity of tumor microenvironment and therefore to bridge the gap between 2D monolayers and animal models. Herein, we present an overview of the 3D systems commonly used for studying tumor–stroma interactions, with a focus on recent advances in cancer modeling and drug discovery and testing.

Cancer-associated fibroblasts in non-small cell lung cancer: Recent advances and future perspectives

Non-small cell lung cancer (NSCLC) constitutes the majority of lung cancer, which is the leading cause of cancer-related deaths in the world. Nearly 70% of NSCLC patients were diagnosed at advanced stage with only 15% of five-year survival rate. Cancer-associated fibroblasts (CAFs) are the major component of tumor microenvironment and account for almost 70% of the cells in tumor tissues. By the crosstalk with cancer cells, CAFs reprogrammed cancer cell metabolism, remodeled extracellular matrix (ECM) and created a supportive niche for cancer stem cells. CAFs lead collective invasion of tumor cells and shape tumor immune microenvironment, promoting tumor metastasis and immune escape. In this review, we have summarized the progress of studies regarding CAFs influences on NSCLC in recent five years from the aspects of cell growth, metabolism, therapy resistance, invasion and metastasis and immune suppression. We have discussed the involved mechanisms and implications for the development of anti-NSCLC therapies. The current strategies of CAFs targeting and elimination have also been generalized. Only better understanding of the molecular biology of CAFs may contribute to the development of novel anti-NSCLC strategies.

Profiling of conditionally reprogrammed cell lines for in vitro chemotherapy response prediction of pancreatic cancer

BACKGROUND

The establishment of patient-derived models for pancreatic ductal adenocarcinoma (PDAC) using conventional methods has been fraught with low success rate, mainly because of the small number of tumour cells and dense fibrotic stroma. Here, we sought to establish patient-derived model of PDAC and perform genetic analysis with responses to anticancer drug by using the conditionally reprogrammed cell (CRC) methodology.

METHODS

We performed in vitro and in vivo tumourigenicity assays and analysed histological characteristics by immunostaining. We investigated genetic profiles including mutation patterns and copy number variations using targeted deep sequencing and copy-number analyses. We assessed the responses of cultured CRCs to the available clinical anticancer drugs based on patient responsiveness.

FINDINGS

We established a total of 28 CRCs from patients. Of the 28 samples, 27 showed KRAS mutations in codon 12/13 or codon 61. We found that somatic mutations were shared in the primary-CRC pairs and shared mutations included key oncogenic mutations such as KRAS (9 pairs), TP53 (8 pairs), and SMAD4 (3 pairs). Overall, CRCs preserved the genetic characteristics of primary tumours with high concordance, with additional confirmation of low-AF NPM1 mutation in CRC (35 shared mutations out of 36 total, concordance rate=97.2%). CRCs of the responder group were more sensitive to anticancer agents than those of the non-responder group (P < 0.001).

INTERPRETATION

These results show that a pancreatic cancer cell line model can be efficiently established using the CRC methodology, to better support a personalized therapeutic approach for pancreatic cancer patients.

FUNDING

2014R1A1A1006272, HI19C0642-060019, 2019R1A2C2008050, 2020R1A2C209958611, and 2020M3E5E204028211.

Developing a 3D B Cell Lymphoma Culture System to Model Antibody Therapy

Diffuse large cell B cell lymphoma (DLBCL) accounts for approximately 30%-40% of all non-Hodgkin lymphoma (NHL) cases. Current first line DLBCL treatment results in long-term remission in more than 60% of cases. However, those patients with primary refractory disease or early relapse exhibit poor prognosis, highlighting a requirement for alternative therapies. Our aim was to develop a novel model of DLBCL that facilitates in vitro testing of current and novel therapies by replicating key components of the tumor microenvironment (TME) in a three-dimensional (3D) culture system that would enable primary DLBCL cell survival and study ex vivo. The TME is a complex ecosystem, comprising malignant and non-malignant cells, including cancer-associated fibroblasts (CAF) and tumor-associated macrophages (TAM) whose reciprocal crosstalk drives tumor initiation and growth while fostering an immunosuppressive milieu enabling its persistence. The requirement to recapitulate, at least to some degree, this complex, interactive network is exemplified by the rapid cell death of primary DLBCL cells removed from their TME and cultured alone in vitro. Building on previously described methodologies to generate lymphoid-like fibroblasts from adipocyte derived stem cells (ADSC), we confirmed lymphocytes, specifically B cells, interacted with this ADSC-derived stroma, in the presence or absence of monocyte-derived macrophages (MDM), in both two-dimensional (2D) cultures and a 3D collagen-based spheroid system. Furthermore, we demonstrated that DLBCL cells cultured in this system interact with its constituent components, resulting in their improved viability as compared to ex-vivo 2D monocultures. We then assessed the utility of this system as a platform to study therapeutics in the context of antibody-directed phagocytosis, using rituximab as a model immunotherapeutic antibody. Overall, we describe a novel 3D spheroid co-culture system comprising key components of the DLBCL TME with the potential to serve as a testbed for novel therapeutics, targeting key cellular constituents of the TME, such as CAF and/or TAM.

Re-expression of REG family and DUOXs genes in CRC organoids by co-culturing with CAFs

Organoids derived from epithelial tumors have recently been utilized as a preclinical model in basic and translational studies. This model is considered to represent the original tumor in terms of 3D structure, genetic and cellular heterogeneity, but not tumor microenvironment. In this study, we established organoids and paired cancer-associated fibroblasts (CAFs) from surgical specimens of colorectal carcinomas (CRCs), and evaluated gene expression profiles in organoids with and without co-culture with CAFs to assess interactions between tumor cells and CAFs in tumor tissues. We found that the expression levels of several genes, which are highly expressed in original CRC tissues, were downregulated in organoids but re-expressed in organoids by co-culturing with CAFs. They comprised immune response- and external stimulus-related genes, e.g., REG family and dual oxidases (DUOXs), which are known to have malignant functions, leading tumor cells to proliferative and/or anti-apoptotic states and drug resistant phenotypes. In addition, the degree of differential induction of REG1 and DUOX2 in the co-culture system varied depending on CAFs from each CRC case. In conclusion, the co-culture system of CRC organoids with paired CAFs was able to partially reproduce the tumor microenvironment.

Mimicking Tumor Hypoxia in Non-Small Cell Lung Cancer Employing Three-Dimensional In Vitro Models

Hypoxia is the most common microenvironment feature of lung cancer tumors, which affects cancer progression, metastasis and metabolism. Oxygen induces both proteomic and genomic changes within tumor cells, which cause many alternations in the tumor microenvironment (TME). This review defines current knowledge in the field of tumor hypoxia in non-small cell lung cancer (NSCLC), including biology, biomarkers, in vitro and in vivo studies and also hypoxia imaging and detection. While classic two-dimensional (2D) in vitro research models reveal some hypoxia dependent manifestations, three-dimensional (3D) cell culture models more accurately replicate the hypoxic TME. In this study, a systematic review of the current NSCLC 3D models that have been able to mimic the hypoxic TME is presented. The multicellular tumor spheroid, organoids, scaffolds, microfluidic devices and 3D bioprinting currently being utilized in NSCLC hypoxia studies are reviewed. Additionally, the utilization of 3D in vitro models for exploring biological and therapeutic parameters in the future is described.

Microbiome dysbiosis in lung cancer: from composition to therapy

The correlations between microbiota dysbiosis and cancer have gained extensive attention and been widely explored. As a leading cancer diagnosis worldwide, lung cancer poses a great threat to human health. The healthy human lungs are consistently exposed to external environment and harbor a specific pattern of microbiota, sharing many key pathological and physiological characteristics with the intestinal tract. Although previous findings uncovered the critical roles of microbiota in tumorigenesis and response to anticancer therapy, most of them were focused on the intestinal microbiota rather than lung microbiota. Notably, the considerable functions of microbiota in maintaining lung homeostasis should not be neglected as the microbiome dysbiosis may promote tumor development and progression through production of cytokines and toxins and multiple other pathways. Despite the fact that increasing studies have revealed the effect of microbiome on the induction of lung cancer and different disease status, the underlying mechanisms and potential therapeutic strategies remained unclear. Herein, we summarized the recent progresses about microbiome in lung cancer and further discussed the role of microbial communities in promoting lung cancer progression and the current status of therapeutic approaches targeting microbiome to alleviate and even cure lung cancer.

The Detection of Plasma Soluble Podoplanin of Patients with Breast Cancer and Its Clinical Signification

Background

Podoplanin (PDPN) is a type-1 membrane sialoglycoprotein that is expressed in many cancer tumors including breast cancer; nonetheless, its roles in tumor occurrence, development, and metastasis are unclear. In this study, we aimed to investigate the clinical significance of plasma soluble PDPN (sPDPN) levels in patients with breast cancer and its significance in the diagnosis and metastasis.

Materials and Methods

Blood samples from healthy controls (CTL), patients with fibroadenomas of breast (FOB), and breast cancer (pathological type: invasive ductal carcinoma, IDC) were collected. sPDPN levels in the plasma of CTL and patients with FOB and IDC were measured by the ELISA.

Results

The plasma sPDPN levels in IDC patients (159 cases, 22.59±3.70 ng/mL) were higher than those in FOB patients (50 cases, 8.29±1.09 ng/mL; P<0.05) and CTL (100 cases, 1.21±0.12 ng/mL; P<0.0001). The sPDPN levels in patients at stage III and stage IV (30.08±4.66 ng/mL) were higher than in patients at stage I and stage II (11.84±1.12 ng/mL; P=0.005). The sPDPN levels in patients with high-moderate and moderate differentiation (17.50±3.02 ng/mL) were lower than those in patients with moderately low and low differentiation (35.73±4.26 ng/mL; P=0.026). The sPDPN levels in patients with metastasis (30.60±4.27 ng/mL) were much higher than those in patients without metastasis (13.02±1.30 ng/mL; P=0.017).

Conclusion

Plasma sPDPN may be used as a new marker for the determination of the clinical stage, differentiation degree, and metastasis status of breast cancer.

Patient-derived cell line, xenograft and organoid models in lung cancer therapy

Lung cancer accounts for most cancer-related deaths worldwide and has an overall 5-year survival rate of ~15%. Cell lines have played important roles in the study of cancer biology and potential therapeutic targets, as well as pre-clinical testing of novel drugs. However, most experimental therapies that have cleared preclinical testing using established cell lines have failed phase III clinical trials. This suggests that such models may not adequately recapitulate patient tumor biology and clinical outcome predictions. Here, we discuss and compare different pre-clinical lung cancer models, including established cell lines, patient-derived cell lines, xenografts and organoids, summarize the methodology for generating these models, and review their relative advantages and limitations in different oncologic research applications. We further discuss additional gaps in patient-derived pre-clinical models to better recapitulate tumor biology and improve their clinical predictive power.

In Vitro Modeling of the Tumor Microenvironment in Tumor Organoids

BACKGROUND

The tumor microenvironment (TME) represents the many components occupying the space within and surrounding a tumor, including cells, signaling factors, extracellular matrix, and vasculature. Each component has the potential to assume many forms and functions which in turn contribute to the overall state of the TME, and further contribute to the progression and disposition of the tumor itself. The sum of these components can drive a tumor towards progression, keep a migratory tumor at bay, or even control chemotherapeutic response. The wide potential for interaction that the TME is an integral part of a tumor's ecosystem, and it is imperative to include it when studying and modeling cancer in vitro. Fortunately, the development of tissue engineering and biofabrication technologies and methodologies have allowed widespread inclusion of TME-based factors into in vitro tissue-equivalent models.

METHODS

In this review, we compiled contemporary literature sources to provide an overview of the field of TME models, ranging from simple to complex.

RESULTS

We have identified important components of the TME, how they can be included in in vitro study, and cover examples across a range of cancer types.

CONCLUSION

Our goal with this text is to provide a foundation for prospective research into the TME.

Mimicking tumor hypoxia and tumor-immune interactions employing three-dimensional in vitro models

The heterogeneous tumor microenvironment (TME) is highly complex and not entirely understood. These complex configurations lead to the generation of oxygen-deprived conditions within the tumor niche, which modulate several intrinsic TME elements to promote immunosuppressive outcomes. Decoding these communications is necessary for designing effective therapeutic strategies that can effectively reduce tumor-associated chemotherapy resistance by employing the inherent potential of the immune system.While classic two-dimensional in vitro research models reveal critical hypoxia-driven biochemical cues, three-dimensional (3D) cell culture models more accurately replicate the TME-immune manifestations. In this study, we review various 3D cell culture models currently being utilized to foster an oxygen-deprived TME, those that assess the dynamics associated with TME-immune cell penetrability within the tumor-like spatial structure, and discuss state of the art 3D systems that attempt recreating hypoxia-driven TME-immune outcomes. We also highlight the importance of integrating various hallmarks, which collectively might influence the functionality of these 3D models.This review strives to supplement perspectives to the quickly-evolving discipline that endeavors to mimic tumor hypoxia and tumor-immune interactions using 3D in vitro models.

Patient-derived cancer modeling for precision medicine in colorectal cancer: beyond the cancer cell line

Since effective immunotherapeutic agents such as immune checkpoint blockade to treat cancer have emerged, the need for reliable preclinical cancer models that can evaluate and discover such drugs became stronger than ever before. The traditional preclinical cancer model using a cancer cell line has several limitations to recapitulate intra-tumor heterogeneity and in-vivo tumor activity including interactions between tumor-microenvironment. In this review, we will go over various preclinical cancer models recently discovered including patient-derived xenografts, humanized mice, organoids, organotypic-tumor spheroids, and organ-on-a-chip models. Moreover, we will discuss the future directions of preclinical cancer research.

Organoid of ovarian cancer: genomic analysis and drug screening

Ovarian cancer is the most common malignant tumors of the female reproductive system, and its standard treatments are cytoreductive surgery and platinum-based adjuvant chemotherapy. Great advances have been achieved in novel treatment strategies, including targeted therapy and immunotherapy. However, ovarian cancer has the highest mortality rate among gynecological tumors due to therapeutic resistance and the gap between preclinical data and actual clinical efficacy. Organoids are a 3D culture model that markedly affects gene analysis, drug screening, and drug sensitivity determination of tumors, especially when used in targeted therapy and immunotherapy. In addition, organoid can lead to advances in the preclinical research of ovarian cancer due to its convenient cultivation, good genetic stability, and high homology with primary tumors.