Colorectal Cancer Patient-Derived 2D and 3D Models Efficiently Recapitulate Inter- and Intratumoral Heterogeneity

Decellularized tissues as platforms for digestive system cancer models

The extracellular matrix (ECM) is a multifunctional network of macromolecules that regulate various cellular functions and physically support the tissues. Besides physiological conditions, the ECM also changes during pathological conditions such as cancer. As tumor cells proliferate, notable changes occur in the quantity and makeup of the surrounding ECM. Therefore, the role of this noncellular component of tissues in studies of tumor microenvironments should be considered. So far, many attempts have been made to create 2-dimensional (2D) or 3-dimensional (3D) models that can replicate the intricate connections within the tumor microenvironment. Decellularized tissues are proper scaffolds that imitate the complex nature of native ECM. This review aims to summarize 3D models of digestive system cancers based on decellularized ECMs. These ECM-based scaffolds will enable us to study the interactive communication between cells and their surrounding environment which brings new potential for a better understanding of the pathophysiology of cancer.

Exploring the potential of thiophene derivatives as dual inhibitors of β-tubulin and Wnt/β-catenin pathways for gastrointestinal cancers in vitro

Background

Gastrointestinal cancer poses a considerable global health risk, encompassing a heterogeneous spectrum of malignancies that afflict the gastrointestinal tract. It is significant to develop efficacious therapeutic agents, as they are indispensable for both the treatment and prevention of this formidable disease.

Methods

In this study, we synthesized a novel thiophene derivative, designated as compound 1312. An assessment was performed to investigate its anti-proliferative activity in several cancer cell lines (GES-1, EC9706, SGC7901, and HT-29). Furthermore, we performed molecular biology techniques to investigate the inhibitory impact of compound 1312 on gastrointestinal cell lines SGC-7901 and HT-29.

Results

Our findings reveal that compound 1312 exhibits significant efficacy in suppressing colony formation of cancer cells. Notably, it triggers cell cycle arrest at the G2/M phase in gastrointestinal cell lines SGC7901 and HT-29. Compound 1312 was confirmed to exert inhibitory effects on cell migration and invasion in SGC7901. Additionally, the compound elicits apoptotic cell death through the activation of the DNA repair enzyme poly (ADP-ribose) polymerase (PARP) and the caspase signaling cascade. Furthermore, in vitro experiments revealed that compound 1312 effectively suppresses both the β-tubulin cytoskeletal network and the Wnt/β-catenin signaling pathway. These multifaceted anti-cancer activities highlight the potential of compound 1312 as a promising therapeutic agent for the treatment of gastrointestinal malignancies.

Conclusion

This study indicates the promising potential of compound 1312 as a prospective candidate agent for gastrointestinal cancer treatment. Further comprehensive investigations are needed to explore its therapeutic efficacy in greater detail.

Distinct molecular profiles drive multifaceted characteristics of colorectal cancer metastatic seeds

Metastasis of primary tumors remains a challenge for early diagnosis and prevention. The cellular properties and molecular drivers of metastatically competent clones within primary tumors remain unclear. Here, we generated 10-16 single cell-derived lines from each of three colorectal cancer (CRC) tumors to identify and characterize metastatic seeds. We found that intrinsic factors conferred clones with distinct metastatic potential and cellular communication capabilities, determining organ-specific metastasis. Poorly differentiated or highly metastatic clones, rather than drug-resistant clones, exhibited poor clinical prognostic impact. Personalized genetic alterations, instead of mutation burden, determined the occurrence of metastatic potential during clonal evolution. Additionally, we developed a gene signature for capturing metastatic potential of primary CRC tumors and demonstrated a strategy for identifying metastatic drivers using isogenic clones with distinct metastatic potential in primary tumors. This study provides insight into the origin and mechanisms of metastasis and will help develop potential anti-metastatic therapeutic targets for CRC patients.

Integration of pan-omics technologies and three-dimensional in vitro tumor models: an approach toward drug discovery and precision medicine

Despite advancements in treatment protocols, cancer is one of the leading cause of deaths worldwide. Therefore, there is a need to identify newer and personalized therapeutic targets along with screening technologies to combat cancer. With the advent of pan-omics technologies, such as genomics, transcriptomics, proteomics, metabolomics, and lipidomics, the scientific community has witnessed an improved molecular and metabolomic understanding of various diseases, including cancer. In addition, three-dimensional (3-D) disease models have been efficiently utilized for understanding disease pathophysiology and as screening tools in drug discovery. An integrated approach utilizing pan-omics technologies and 3-D in vitro tumor models has led to improved understanding of the intricate network encompassing various signalling pathways and molecular cross-talk in solid tumors. In the present review, we underscore the current trends in omics technologies and highlight their role in understanding genotypic-phenotypic co-relation in cancer with respect to 3-D in vitro tumor models. We further discuss the challenges associated with omics technologies and provide our outlook on the future applications of these technologies in drug discovery and precision medicine for improved management of cancer.

A PDA-Functionalized 3D Lung Scaffold Bioplatform to Construct Complicated Breast Tumor Microenvironment for Anticancer Drug Screening and Immunotherapy

2D cell culture occupies an important place in cancer progression and drug discovery research. However, it limitedly models the "true biology" of tumors in vivo. 3D tumor culture systems can better mimic tumor characteristics for anticancer drug discovery but still maintain great challenges. Herein, polydopamine (PDA)-modified decellularized lung scaffolds are designed and can serve as a functional biosystem to study tumor progression and anticancer drug screening, as well as mimic the tumor microenvironment. PDA-modified scaffolds with strong hydrophilicity and excellent cell compatibility can promote cell growth and proliferation. After 96 h treatment with 5-FU, cisplatin, and DOX, higher survival rates in PDA-modified scaffolds are observed compared to nonmodified scaffolds and 2D systems. The E-cadhesion formation, HIF-1α-mediated senescence decrease, and tumor stemness enhancement can drive drug resistance and antitumor drug screening of breast cancer cells. Moreover, there is a higher survival rate of CD45+ /CD3+ /CD4+ /CD8+ T cells in PDA-modified scaffolds for potential cancer immunotherapy drug screening. This PDA-modified tumor bioplatform will supply some promising information for studying tumor progression, overcoming tumor resistance, and screening tumor immunotherapy drugs.

[Metformin inhibits self-renewal of colorectal cancer stem cells by inhibiting mitochondrial oxidative phosphorylation]

OBJECTIVE

To investigate the mechanism of metformin for inhibiting self-renewal of colorectal cancer stem cells (CSCs).

METHODS

CSCs were sorted from Wnt reporter- transfected colorectal cancer patient-derived organoids (PDOs) by fluorescence-activated cell sorting (FACS) and treated with metformin. The changes in self-renewal of the cells were assessed using sphere formation, colony formation and limiting dilution assays. The mRNA expressions of genes related with stemness and differentiation and Wnt target genes was detected by qRT-PCR. Wnt activity was assessed using flow cytometry in the CSCs. Seahorse analysis was used to evaluate cellular oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) after metformin treatment. Mitochondrial membrane potential levels were detected with TMRE staining, and reactive oxygen species (ROS) levels were detected using MitoSOX staining. Galactose (10 mmol/L), metformin (10 μmol/L), NAC (5 mmol/L), and galactose+metformin were used to modulate ROS levels in the CSCs, and sphere-formation assay and flow cytometry were used to assess the changes in self- renewal capacity and Wnt activity. The effect of lentiviral transfection of yeast NADH dehydrogenase NDI1 on TMRE staining, MitoSOX staining and Wnt activity in the CSCs were analyzed with flow cytometry.

RESULTS

Metformin significantly decreased the capacities of CSCs to form spheres, colonies and xenografts and reduced Wnt activity in the cells (P < 0.01). The mRNA levels of stemness-related genes and Wnt target genes decreased significantly while those of differentiation-related genes increased in metformin-treated CSCs (P < 0.05), which also showed significantly decreased OCR, TMRE and ROS levels with enhanced ECAR (P < 0.001). Galactose significantly increased sphereforming capacity, ROS levels and Wnt activity of the cells, and these effects were significantly inhibited by metformin (P < 0.05). Transfection of the CSCs with NDI1 significantly attenuated the inhibitory effects of metformin on proportion of CSCs and Wnt signaling pathway activity.

CONCLUSION

Metformin reduces mitochondrial oxidative phosphorylation and ROS levels by inhibiting mitochondrial complex Ⅰ, thereby suppressing Wnt signaling pathway to reduce selfrenewal ability of colorectal CSCs.

Colonic stem cells from normal tissues adjacent to tumor drive inflammation and fibrosis in colorectal cancer

BACKGROUND

In colorectal cancer (CRC), the normal tissue adjacent to tumor (NAT) communicates actively with the tumor. Adult stem cells from the colon play a crucial role in the development of the colonic epithelium. In the tumor microenvironment, however, it is unclear what changes have occurred in colonic stem cells derived from NAT.

METHODS

Using an intestinal stem cell culture system, we cultured colonic cells from NAT and paired CRC tissue, as well as cells from healthy tissue (HLT). Clonogenicity and differentiation ability were used to compare the function of clones from NAT, HLT and CRC tissues. RNA high-throughput sequencing of these clones was used to identify the molecular characteristics of NAT-derived clones. Coculture of clones from HLT and CRC was used to assess molecular changes.

RESULTS

We found that the morphological characteristics, clonogenic ability, and differentiation ability of NAT-derived clones were consistent with those of HLT-derived clones. However, NAT-derived clones changed at the molecular level. A number of genes were specifically activated in NAT. NAT-derived clones enriched pathways related to inflammation and fibrosis, including epithelial mesenchymal transition (EMT) pathway and TGF-beta signaling pathway. Our results also confirmed that NAT-derived clones could recruit fibroblasts in mice. In addition, HLT-derived clones showed high expression of FOSB when cocultured with tumor cells.

CONCLUSIONS

Our results demonstrate that colonic stem cells from NAT in the tumor microenvironment undergo changes at the molecular level, and these molecular characteristics can be maintained in vitro, which can induce fibrosis and an inflammatory response. Video Abstract.

Standard: Human intestinal cancer organoids

Intestinal cancer is one of the most frequent and lethal types of cancer. Modeling intestinal cancer using organoids has emerged in the last decade. Human intestinal cancer organoids are physiologically relevant in vitro models, which provides an unprecedented opportunity for fundamental and applied research in colorectal cancer. "Human intestinal cancer organoids" is the first set of guidelines on human intestinal organoids in China, jointly drafted and agreed by the experts from the Chinese Society for Cell Biology and its branch society: the Chinese Society for Stem Cell Research. This standard specifies terms and definitions, technical requirements, test methods for human intestinal cancer organoids, which apply to the production and quality control during the process of manufacturing and testing of human intestinal cancer organoids. It was released by the Chinese Society for Cell Biology on 24 September 2022. We hope that the publication of this standard will guide institutional establishment, acceptance and execution of proper practocal protocols, and accelerate the international standardization of human intestinal cancer organoids for clinical development and therapeutic applications.

The applications and techniques of organoids in head and neck cancer therapy

Head and neck cancer (HNC) is one of the most common cancers on the planet, with approximately 600,000 new cases diagnosed and 300,000 deaths every year. Research into the biological basis of HNC has advanced slowly over the past decades, which has made it difficult to develop new, more effective treatments. The patient-derived organoids (PDOs) are made from patient tumor cells, resembling the features of their tumors, which are high-fidelity models for studying cancer biology and designing new precision medicine therapies. In recent years, considerable effort has been focused on improving "organoids" technologies and identifying tumor-specific medicine using head and neck samples and a variety of organoids. A review of improved techniques and conclusions reported in publications describing the application of these techniques to HNC organoids is presented here. Additionally, we discuss the potential application of organoids in head and neck cancer research as well as the limitations associated with these models. As a result of the integration of organoid models into future precision medicine research and therapeutic profiling programs, the use of organoids will be extremely significant in the future.

In vitro models to study human gut-microbiota interactions: Applications, advances, and limitations

In vitro models of the human gut help compensate for the limitations of animal models in studying the human gut-microbiota interaction and are indispensable in the clarification the mechanism of microbial action or in the high-throughput screening and functional evaluation of probiotics. The development of these models constitutes a rapidly developing field of research. From 2D¹ to 3D² and from simple to complex, several in vitro cell and tissue models have been developed and continuously improved. In this review, we categorized and summarized these models and described their development, applications, advances, and limitations by using specific examples. We also highlighted the best ways to select an appropriate in vitro model, and we also discussed which variables to consider when imitating microbial and human gut epithelial interactions.