The Role of Mechanical Properties and Structure of Type I Collagen Hydrogels on Colorectal Cancer Cell Migration

A Novel Multicompartment Barrier-Free Microfluidic Device Reveals the Impact of Extracellular Matrix Stiffening and Temozolomide on Immune-Tumor Interactions in Glioblastoma

The immune system plays a crucial role in shaping the glioblastoma tumor microenvironment, characterized by its complexity and dynamic interactions. Understanding the tumor-immune crosstalk is essential for advancing cancer research and therapeutic development. Here, a novel multicompartment, barrier-free microfluidic device is presented that overcomes the limitations of existing models by enabling direct tumor-immune interactions without physical barriers, preserving natural immune cell infiltration. This platform supports the independent and simultaneous culture of tumor and immune cells, replicating the healthy-tumoral stroma interface, and allows investigating the effect of matrix stiffness and chemotherapy on both populations. The findings reveal that increased collagen concentration promotes tumor invasiveness while impairing immune cell infiltration. Additionally, temozolomide treatment reduces immune cell motility but enhances anti-tumor immune responses. These insights highlight the critical roles of extracellular matrix mechanics and chemotherapy in tumor progression and immune modulation, establishing this device as a powerful tool for studying glioblastoma-immune dynamics and evaluating therapeutic strategies.

Decoupling chemical and mechanical signaling in colorectal cancer cell migration

Colorectal cancer metastasis is governed by a variety of chemical and mechanical signaling that are largely influenced by cancer-associated fibroblasts (CAFs) in the tumor microenvironment. Here, we deconvolute the chemical from mechanical signaling in the case of the colon cancer cell line HCT-116 and CAFs. We examined three chemoattractants (CXCL12, TGF-β, and activin A) which allegedly are secreted by CAFs and induce HCT-116 cell migration. None of the chemoattractants tested resulted in enhanced migration of HCT-116 in a 2D transwell assay, at low cell density. Similarly, CAF-conditioned media also did not lead to enhanced HCT-116 migration, while CAFs co-cultured in the transwell assay did lead to increased HCT-116 migration. This result suggests that either high cell densities are required for chemotaxis, and/or a reciprocal two-way signaling network between CAFs and HCT-116 is necessary to induce chemotaxis. Surprisingly, we find that HCT-116 cells exhibit enhanced migration along the axis of mechanical stress in a 3D collagen matrix, at very high cell densities. This migration is independent of whether the strain is induced mechanically or by CAFs. By comparing purely mechanical and purely chemical migration to a 3D co-culture of CAFs and HCT-116 containing both chemical and mechanical cues, it is concluded that HCT-116 migration is dominated by mechanical signaling, while chemical cues are less influential.

EMT-related cell-matrix interactions are linked to states of cell unjamming in cancer spheroid invasion

Epithelial-to-mesenchymal transitions (EMT) and unjamming transitions provide two distinct pathways for cancer cells to become invasive, but it is still unclear to what extent these pathways are connected. Here, we addressed this question by performing 3D spheroid invasion assays on epithelial-like (A549) and mesenchymal-like (MV3) cancer cell lines in collagen-based hydrogels, where we varied both the invasive character of the cells and matrix porosity. We found that the onset time of invasion was correlated with the matrix porosity and vimentin levels, while the spheroid expansion rate correlated with MMP1 levels. Spheroids displayed solid-like (non-invasive) states in small-pore hydrogels and fluid-like (strand-based) or gas-like (disseminating cells) states in large-pore hydrogels or for mesenchymal-like cells. Our findings are consistent with different unjamming states as a function of cell motility and matrix confinement predicted in recent models for cancer invasion, but show that cell motility and matrix confinement are coupled via EMT-related matrix degradation.

Innovative theranostic hydrogels for targeted gastrointestinal cancer treatment

Gastrointestinal tumors are the main causes of death among the patients. These tumors are mainly diagnosed in the advanced stages and their response to therapy is unfavorable. In spite of the development of conventional therapeutics including surgery, chemotherapy, radiotherapy and immunotherapy, the treatment of these tumors is still challenging. As a result, the new therapeutics based on (nano)biotechnology have been introduced. Hydrogels are polymeric 3D networks capable of absorbing water to swell with favorable biocompatibility. In spite of application of hydrogels in the treatment of different human diseases, their wide application in cancer therapy has been improved because of their potential in drug and gene delivery, boosting chemotherapy and immunotherapy as well as development of vaccines. The current review focuses on the role of hydrogels in the treatment of gastrointestinal tumors. Hydrogels provide delivery of drugs (both natural or synthetic compounds and their co-delivery) along with gene delivery. Along with delivery, hydrogels stimulate phototherapy (photothermal and photodynamic therapy) in the suppression of these tumors. Besides, the ability of hydrogels for the induction of immune-related cells such as dendritic cells can boost cancer immunotherapy. For more specific cancer therapy, the stimuli-responsive types of hydrogels including thermo- and pH-sensitive hydrogels along with their self-healing ability have improved the site specific drug delivery. Moreover, hydrogels are promising for diagnosis, circulating tumor cell isolation and detection of biomarkers in the gastrointestinal tumors, highlighting their importance in clinic. Hence, hydrogels are diagnostic and therapeutic tools for the gastrointestimal tumors.

Correlating Ultrastructural Changes in the Invasion Area of Colorectal Cancer with CT and MRI Imaging

The cancer invasion of the large intestine, a destructive process that begins within the mucous membrane, causes cancer cells to gradually erode specific layers of the intestinal wall. The normal tissues of the intestine are progressively replaced by a tumour mass, leading to the impairment of the large intestine's proper morphology and function. At the ultrastructural level, the disintegration of the extracellular matrix (ECM) by cancer cells triggers the activation of inflammatory cells (macrophages) and connective tissue cells (myofibroblasts) in this area. This accumulation and the functional interactions between these cells form the tumour microenvironment (TM). The constant modulation of cancer cells and cancer-associated fibroblasts (CAFs) creates a specific milieu akin to non-healing wounds, which induces colon cancer cell proliferation and promotes their survival. This review focuses on the processes occurring at the "front of cancer invasion", with a particular focus on the role of the desmoplastic reaction in neoplasm development. It then correlates the findings from the microscopic observation of the cancer's ultrastructure with the potential of modern radiological imaging, such as computer tomography (CT) and magnetic resonance imaging (MRI), which visualizes the tumour, its boundaries, and the tissue reactions in the large intestine.

Clonorchis sinensis infection induces pathological changes in feline bile duct epithelium and alters biliary microbiota composition

BACKGROUND

Clonorchis sinensis is a zoonotic liver fluke that inhabits the bile ducts of the human liver for prolonged periods, leading to cholangiocarcinoma. Recent research indicates associations between altered biliary microbiota and bile duct disorders. However, the impacts of C. sinensis infection on bile duct epithelium and subsequent effects on biliary microbiota remain unknown.

METHODS

Feline bile duct samples were collected from both uninfected and C. sinensis-infected cats. Histopathological examination was performed to assess epithelial changes, fibrosis, mucin and cell proliferation using hematoxylin-eosin staining and immunohistochemistry. Additionally, biliary microbiota composition was analyzed through 16S rRNA gene sequencing. Statistical analyses were conducted to compare the microbial diversity and relative abundance between infected and uninfected samples.

RESULTS

Histopathological analysis of infected feline bile ducts revealed prominent epithelial hyperplasia characterized by increased cell proliferation. Moreover, periductal fibrosis and collagen fibrosis were observed in infected samples compared to uninfected controls. Biliary microbial richness decreased with disease progression compared to uninfected controls. Streptococcus abundance positively correlated with disease severity, dominating communities in cancer samples. Predictive functional analysis suggested that C. sinensis may promote bile duct lesions by increasing microbial genes for carbohydrate metabolism, replication, and repair.

CONCLUSIONS

This study provides comprehensive insights into the pathological effects of C. sinensis infection on feline bile duct epithelium and its influence on biliary microbiota composition. These novel findings provide insight into C. sinensis pathogenesis and could inform therapeutic development against human clonorchiasis. Further research is warranted to elucidate the underlying mechanisms driving these changes and their implications for host-parasite interactions.

Biomimetic Hydrogel Strategies for Cancer Therapy

Recent developments in biomimetic hydrogel research have expanded the scope of biomedical technologies that can be used to model, diagnose, and treat a wide range of medical conditions. Cancer presents one of the most intractable challenges in this arena due to the surreptitious mechanisms that it employs to evade detection and treatment. In order to address these challenges, biomimetic design principles can be adapted to beat cancer at its own game. Biomimetic design strategies are inspired by natural biological systems and offer promising opportunities for developing life-changing methods to model, detect, diagnose, treat, and cure various types of static and metastatic cancers. In particular, focusing on the cellular and subcellular phenomena that serve as fundamental drivers for the peculiar behavioral traits of cancer can provide rich insights into eradicating cancer in all of its manifestations. This review highlights promising developments in biomimetic nanocomposite hydrogels that contribute to cancer therapies via enhanced drug delivery strategies and modeling cancer mechanobiology phenomena in relation to metastasis and synergistic sensing systems. Creative efforts to amplify biomimetic design research to advance the development of more effective cancer therapies will be discussed in alignment with international collaborative goals to cure cancer.

Reducing Inert Materials for Optimal Cell-Cell and Cell-Matrix Interactions within Microphysiological Systems

In the pursuit of achieving a more realistic in vitro simulation of human biological tissues, microfluidics has emerged as a promising technology. Organ-on-a-chip (OoC) devices, a product of this technology, contain miniature tissues within microfluidic chips, aiming to closely mimic the in vivo environment. However, a notable drawback is the presence of inert material between compartments, hindering complete contact between biological tissues. Current membranes, often made of PDMS or plastic materials, prevent full interaction between cell types and nutrients. Furthermore, their non-physiological mechanical properties and composition may induce unexpected cell responses. Therefore, it is essential to minimize the contact area between cells and the inert materials while simultaneously maximizing the direct contact between cells and matrices in different compartments. The main objective of this work is to minimize inert materials within the microfluidic chip while preserving proper cellular distribution. Two microfluidic devices were designed, each with a specific focus on maximizing direct cell-matrix or cell-cell interactions. The first chip, designed to increase direct cell-cell interactions, incorporates a nylon mesh with regular pores of 150 microns. The second chip minimizes interference from inert materials, thereby aiming to increase direct cell-matrix contact. It features an inert membrane with optimized macropores of 1 mm of diameter for collagen hydrogel deposition. Biological validation of both devices has been conducted through the implementation of cell migration and cell-to-cell interaction assays, as well as the development of epithelia, from isolated cells or spheroids. This endeavor contributes to the advancement of microfluidic technology, aimed at enhancing the precision and biological relevance of in vitro simulations in pursuit of more biomimetic models.

Human Dermal Decellularized ECM Hydrogels as Scaffolds for 3D In Vitro Skin Aging Models

Biomaterials play an important role in the development of advancing three dimensional (3D) in vitro skin models, providing valuable insights for drug testing and tissue-specific modeling. Commercial materials, such as collagen, fibrin or alginate, have been widely used in skin modeling. However, they do not adequately represent the molecular complexity of skin components. On this regard, the development of novel biomaterials that represent the complexity of tissues is becoming more important in the design of advanced models. In this study, we have obtained aged human decellularized dermal extracellular matrix (dECM) hydrogels extracted from cadaveric human skin and demonstrated their potential as scaffold for advanced skin models. These dECM hydrogels effectively reproduce the complex fibrillar structure of other common scaffolds, exhibiting similar mechanical properties, while preserving the molecular composition of the native dermis. It is worth noting that fibroblasts embedded within human dECM hydrogels exhibit a behavior more representative of natural skin compared to commercial collagen hydrogels, where uncontrolled cell proliferation leads to material shrinkage. The described human dECM hydrogel is able to be used as scaffold for dermal fibroblasts in a skin aging-on-a-chip model. These results demonstrate that dECM hydrogels preserve essential components of the native human dermis making them a suitable option for the development of 3D skin aging models that accurately represent the cellular microenvironment, improving existing in vitro skin models and allowing for more reliable results in dermatopathological studies.

Investigating the Impact of Mechanical Properties and Cell-Collagen Interaction on NIH3T3 Function: A Comparative Study on Different Substrates and Culture Environments

This study investigates the intricate dynamics of matrix stiffness, substrate composition, and cell-cell interactions and elucidates their cumulative effects on fibroblast behavior in different culture contexts. Three primary substrate types were examined: non-coated, collagen-coated, and collagen hydrogel, within both two-dimensional (2D) monolayer and three-dimensional (3D) spheroid cultures. The research provides several key insights. First, 3D spheroid culture, which promotes robust cell-cell interactions, emerges as a critical factor in maintaining fibroblast functionality. Second, substrate stiffness significantly influences results, with the soft collagen hydrogel showing superior support for fibroblast function. Notably, fibroblasts cultured on collagen hydrogel in 2D exhibit comparable functionality to those in 3D, highlighting the importance of substrate mechanical properties. Third, surface composition, as exemplified by collagen coating, showed a limited effect compared to the other factors studied. These findings provide a basis for innovative applications in regenerative medicine, tissue engineering, and drug testing models, and offer valuable insights into harnessing the potential of fibroblasts and advancing biomedical sciences.