Biological role of matrix stiffness in tumor growth and treatment

3D bioprinted microfluidic based osteosarcoma-on-a chip model as a physiomimetic pre-clinical drug testing platform for anti-cancer drugs

Standard chemotherapeutic regimen for osteosarcoma (OS) treatment often leads to poor therapeutic outcome, primarily due to lack of an adequate representative model reflecting native OS structural and cellular complexity, posing a translational gap. Three-dimensional bioprinting (3D-BP) represents an efficient and advanced technique for precise recapitulation of the structural and cellular complexity of OS tumor microenvironment (TME). In the present study, we employed a dual extrusion-based 3D-BP method to develop an improved in vitro OS model consisting of both tumor and stromal components. Additionally, a human physiomimetic microfluidic bioreactor is introduced to mimic the dynamic TME and provide physiologically relevant mechanical stimulation to the cells. The model named TC-OS Dynamic model, demonstrated close resemblance to native OS-TME, validated by in vitro studies. Continuous media flow provided mechanical stimulation in the form of shear stress, positively influencing the growth and aggressiveness of OS. Further, drug screening with the model anticancer drugs (doxorubicin, cis-platin, sorafenib) demonstrated enhanced sensitivity in TC-OS Dynamic model as compared to TC-OS Static model, emphasizing enhanced mass transfer, availability and distribution of anticancer drug due to continuous media flow. Overall, TC-OS Dynamic model holds significant potential as a platform in future for high throughput pre-clinical screening of anticancer drugs.

Interactions and communications in lung tumour microenvironment: chemo/radiotherapy resistance mechanisms and therapeutic targets

The lung tumour microenvironment (TME) is composed of various cell types, including cancer cells, stromal and immune cells, as well as extracellular matrix (ECM). These cells and surrounding ECM create a stiff, hypoxic, acidic and immunosuppressive microenvironment that can augment the resistance of lung tumours to different forms of cell death and facilitate invasion and metastasis. This environment can induce chemo/radiotherapy resistance by inducing anti-apoptosis mediators such as phosphoinositide 3-kinase (PI3K)/Akt, signal transducer and activator of transcription 3 (STAT3) and nuclear factor kappa B (NF-κB), leading to the exhaustion of antitumor immunity and further resistance to chemo/radiotherapy. In addition, lung tumour cells can resist chemo/radiotherapy by boosting multidrug resistance mechanisms and antioxidant defence systems within cancer cells and other TME components. In this review, we discuss the interactions and communications between these different components of the lung TME and also the effects of hypoxia, immune evasion and ECM remodelling on lung cancer resistance. Finally, we review the current strategies in preclinical and clinical studies, including the inhibition of checkpoint molecules, chemoattractants, cytokines, growth factors and immunosuppressive mediators such as programmed death 1 (PD-1), insulin-like growth factor 2 (IGF-2) for targeting the lung TME to overcome resistance to chemotherapy and radiotherapy.

Smart materials in pharmacological drug development: Neutrophils and its constituents for drug delivery and consequent antitumor effects

Neutrophil-based drug delivery systems for targeted therapy of cancer have been studied widely in the recent past. Chemotactic cytokines including colony-stimulating factors (CSFs) recruit various immune cells including the neutrophils to the tumor microenvironment (TME) leading to enhanced metastasis. These cytokines can be targeted effectively by immunotherapeutic agents such as checkpoint inhibitors and mAbs that can lead to systemic toxicity. To minimize the systemic adverse effects, camouflaged nanoparticles can be used significantly as alternative therapeutic agents. The neutrophil-interacting NPs and neutrophil membrane coated NPs have been exploited recently for their antitumor properties in vitro and pose limited systemic adverse effects in vivo. Neutrophil-derived exosomes derived from immune cells can efficiently escape immune-surveillance and pass through the blood-brain barrier. They possess several intrinsic properties in drug delivery as they are nano-sized, extremely biocompatible, non-immunogenic, biodegradable, stable and can carry targeting agents with limited toxicity and display antitumor properties. Also, neutrophil-based nanotherapy is dependent on factors such as neutrophil kinetics and the physicochemical properties of NPs such as size, shape, and surface chemistry. Therefore, neutrophil-based drug delivery for cancer therapy via the use of polymer nanoparticles is widely studied as their clinical appliance in nanomedicine is still at its infancy.

Mechanometabolism: recent findings on the intersection of cell adhesion, cell migration, and metabolism

Chemical and mechanical cues within the extracellular matrix (ECM) can initiate intracellular signaling that changes an array of fundamental cell functions. In recent work, studies of cell-ECM adhesion have deepened to include the influence of the physical ECM on cell metabolism. Since many biological processes involve metabolic programs, changes to cellular metabolism in response to cues in the ECM can have marked effects on cell health. In this review, we describe molecular mechanisms associated with cell-ECM adhesion that are key players in metabolism-induced changes to cell behaviors, including migration. We first review how changes to metabolite availability in the extracellular environment or manipulation of metabolic machinery in cells impact focal adhesions. We then connect this work to recent findings regarding the reverse relationship, namely, how the manipulation of focal adhesion proteins or integrins feeds back to alter cell metabolism. Finally, we consider the latest findings from studies that describe how the mechanical properties of the ECM, primarily stiffness and confinement, alter cellular metabolism. We identify key areas of future investigation that may elucidate the molecular drivers that permit cells to respond to mechanical and chemical ECM cues by reprogramming their metabolism to better inform future diagnostics and therapeutics for disease states.

Beyond mechanosensing: How cells sense and shape their physical environment during development

The role of mechanics as a regulator of cell behaviour and embryo development has been widely recognised. However, much of the focus in mechanobiology during embryo development has been on how the mechanical properties of a cell affect its behaviour and fate determination. We discuss the role of mechanosignalling in development and propose that an equally important aspect of embryo mechanobiology is understanding how dynamic changes in tissue mechanics are regulated. Comparably to how chemical signals influence the fate of responding tissues during embryonic induction, we suggest that embryonic cell populations can alter the mechanical properties of adjacent tissues in a process we name 'actuation'. Several examples of embryonic actuation and mechanical feedback are discussed.

Computational modeling of breast tissue mechanics and machine learning in cancer diagnostics: enhancing precision in risk prediction and therapeutic strategies

INTRODUCTION

Breast cancer remains a significant global health issue. Despite advances in detection and treatment, its complexity is driven by genetic, environmental, and structural factors. Computational methods like Finite Element Modeling (FEM) have transformed our understanding of breast cancer risk and progression.

AREAS COVERED

Advanced computational approaches in breast cancer research are the focus, with an emphasis on FEM's role in simulating breast tissue mechanics and enhancing precision in therapies such as radiofrequency ablation (RFA). Machine learning (ML), particularly Convolutional Neural Networks (CNNs), has revolutionized imaging modalities like mammograms and MRIs, improving diagnostic accuracy and early detection. AI applications in analyzing histopathological images have advanced tumor classification and grading, offering consistency and reducing inter-observer variability. Explainability tools like Grad-CAM, SHAP, and LIME enhance the transparency of AI-driven models, facilitating their integration into clinical workflows.

EXPERT OPINION

Integrating FEM and ML represents a paradigm shift in breast cancer management. FEM offers precise modeling of tissue mechanics, while ML excels in predictive analytics and image analysis. Despite challenges such as data variability and limited standardization, synergizing these approaches promises adaptive, personalized care. These computational methods have the potential to redefine diagnostics, optimize treatment, and improve patient outcomes.

Extracellular matrix: unlocking new avenues in cancer treatment

The extracellular matrix (ECM) plays a critical role in cancer progression by influencing tumor growth, invasion, and metastasis. This review explores the emerging therapeutic strategies that target the ECM as a novel approach in cancer treatment. By disrupting the structural and biochemical interactions within the tumor microenvironment, ECM-targeted therapies aim to inhibit cancer progression and overcome therapeutic resistance. We examine the current state of ECM research, focusing on key components such as collagen, laminin, fibronectin, periostin, and hyaluronic acid, and their roles in tumor biology. Additionally, we discuss the challenges associated with ECM-targeted therapies, including drug delivery, specificity, and potential side effects, while highlighting recent advancements and future directions. This review underscores the potential of ECM-focused strategies to enhance the efficacy of existing treatments and contribute to more effective cancer therapies.

Soft matrix promotes immunosuppression in tumor-resident immune cells via COX-FGF2 signaling

Mechanical forces of the tumor microenvironment change dynamically during key events of tumorigenesis such as invasion and metastasis. These changes in compressive forces often affect the breast cancer cell phenotype. However, it is lesser known how these dynamic mechanical forces in the tumor microenvironment affect the phenotypes of tumor infiltrated leukocytes (TIL) and their subsequent anticancer activities. Here we find, in primary patient-derived explant cultures (PDEC) containing resident TILs, that low compression promotes a change in the original identity of breast cancer cells from luminal to a more mesenchymal and undifferentiated state. These altered tumor cells induce an upregulation of immunosuppressive cytokines such as interleukin-10 (IL-10) and Transforming Growth Factor Beta (TGF-β), as well as polarization of macrophages towards pro-tumor M2(Gc)-type and depletion of CD8+ effector memory T-cells. These immunosuppressive events are mediated by tumor cell derived fibroblast growth factor 2 (FGF2) and prostaglandin E2 (PGE2). We also find that FGF2 rich areas in primary tumors show enrichment in M2-like-macrophages and diminished numbers of CD8 + T and B-cells. Our results suggest that low compressive forces in the tumor microenvironment induce local immunosuppression via FGF2 secretion arising from phenotypic plasticity of tumor cells.

Fibrogenesis-driven tumor progression in clear cell renal cell carcinoma: prognostic, therapeutic implications and the dual role of neuropilin-1

BACKGROUND

Clear cell renal cell carcinoma (ccRCC) is the predominant subtype of renal cancer, with a poor prognosis driven by therapy resistance and a propensity for recurrence. Tumor microenvironment (TME)-associated fibrosis accelerates disease progression by fostering immune evasion. Neuropilin-1 (NRP1), a key mediator in fibrotic signaling and cancer biology, has been implicated in these processes. However, the genetic correlation between fibrogenesis and ccRCC remains largely unexplored, necessitating a focused analysis of fibrogenesis-related genes (FRGs) to identify novel prognostic markers and therapeutic strategies.

METHODS

This study utilized an integrative bioinformatics framework to identify prognosis-associated fibrogenesis-related genes (pFRGs) and applied non-negative matrix factorization (NMF) to stratify ccRCC patients based on fibrotic signatures. A machine learning-derived prognostic model was developed to categorize patients into high-risk and low-risk groups, with tumor microenvironment (TME) features analyzed across these subgroups. The pro-tumorigenic role of NRP1 via the TGF-β/SMAD signaling pathway was validated in vitro and in vivo.

RESULTS

Twelve pFRGs were identified, with elevated expression correlating with reduced survival. NMF revealed two ccRCC subtypes with different fibrotic and immune profiles. The high-fibrosis subtype showed worse survival and a pro-tumorigenic TME. The risk model demonstrated robust predictive performance (AUCs: 0.738, 0.731, 0.711 for 1-, 2-, and 3-year survival). High-risk patients, marked by immune dysfunction, exhibited worse survival but greater immunotherapy sensitivity. Among the pFRGs, NRP1 was upregulated in ccRCC, and paradoxically associated with favorable prognosis in TCGA, primarily due to stromal enrichment. In vitro and in vivo experiments confirmed that NRP1 promotes ccRCC proliferation, migration, and invasion by enhancing TGF-β/SMAD-driven epithelial-mesenchymal transition (EMT).

CONCLUSION

Fibrosis is a critical driver of ccRCC progression, linking fibrogenesis-related genes to poor prognosis, immune suppression, and tumor aggressiveness. NRP1 was identified as a central regulator of fibrosis-induced tumor progression through the TGF-β/SMAD signaling pathway. Combining NRP1 inhibition with anti-fibrotic therapies presents a potential strategy for enhancing therapeutic outcomes in ccRCC.

Click chemistry-based quantification of extracellular matrix turnover for drug screening and regenerative medicine

This study presents a sensitive and cost-efficient method to quantify extracellular matrix (ECM) synthesis and degradation using copper-free click chemistry reactions to fluorescently label new ECM components. The approach enables spatial visualization and longitudinal measurement of specific ECM turnover in vitro. We validated the method across multiple platforms, including native cartilage explants and monolayer cultures of human mesenchymal stem cells and breast cancer cells. The technique also proved effective for osteoarthritis drug screening by detecting compounds that mitigate inflammation-induced ECM degradation. Compared to traditional biochemical or histological assays, this click chemistry-based technique offers higher sensitivity, lower sample requirements, and improved temporal resolution. Its versatility supports broad applications in tissue engineering, regenerative medicine, disease modeling, and high-throughput drug evaluation.

A comprehensive protocol for PDMS fabrication for use in cell culture

Cells exhibit remarkable sensitivity to the mechanical properties of their surrounding matrix, particularly stiffness changes, a phenomenon known as cellular mechanotransduction. In vivo, tissues exhibit a wide range of stiffness, from kilopascals (kPa) to megapascals (MPa), which can alter with aging and disease. Traditional cell culture methods employ plastic substrates with stiffness in the gigapascal range, which does not accurately mimic the physiological conditions of most biological tissues. Therefore, employing substrates that can be engineered to span a wide range of stiffnesses, closely resembling the native tissue environment, is crucial for obtaining results that more accurately reflect cellular responses in vivo. Polydimethylsiloxane (PDMS) substrates are widely used in cell culture for their ability to simulate tissue stiffness, but their optimization presents several challenges. Fabrication requires precise control over mixing, weighing, and curing to ensure reproducible mechanical properties. Inconsistent preparation can lead to improperly cured PDMS substrates, compromising experimental outcomes. Additionally, PDMS's inherent hydrophobicity poses challenges for cell attachment, necessitating surface modifications to enhance adhesion. Moreover, the risk of contamination during the sterilization process necessitates stringent protocols to maintain cell culture integrity. These challenges are further compounded by substrate autofluorescence which can cause difficulties when imaging cells. The aim of this study is to develop a standardized method for fabricating PDMS substrates with tuneable stiffness, ranging from kPa to MPa, suitable for diverse cell types using standard laboratory equipment. This method aims to minimize the complexity and equipment required for PDMS fabrication, ensuring reproducibility and ease of use. Achieving consistent and contaminant-free PDMS substrates will facilitate a broader adoption of these substrates in mechanobiology research and improve the relevance of in vitro models to in vivo conditions. Ultimately, contributing to a more comprehensive understanding of cellular responses to mechanical cues in health and disease.

Targeting CAFs and extracellular matrix (ECM) in lung cancer: Potential of adjuvants and nanoparticles

Cancer-associated fibroblasts (CAFs) are prominent components of the lung tumor stroma and are known to foster tumor growth, invasion, and metastasis through extracellular matrix (ECM) and tumor stroma remodeling. The interactions of CAFs with cancer cells and other stromal components contribute significantly to the aggressive nature of lung cancer and pose challenges to conventional treatment approaches. Simultaneously, the ECM, which contains numerous proteins and other molecules surrounding cancer cells, serves as more than just a structural scaffold. In lung cancer, alterations in ECM composition and organization not only promote tumor cell proliferation and survival but also impact drug penetration, immune cell infiltration, and therapeutic resistance. Targeting the intricate interplay between CAFs and the dynamic ECM in lung cancer represents a crucial frontier in oncology research. This review aims to delve deeply into the pivotal roles of CAFs and the ECM in the tumorigenesis and progression of lung cancer. Then, the potential of utilizing adjuvants, phytochemicals, and nanoparticles to modulate the functions of CAFs and remodel the ECM in the lung tumor will be reviewed.

Role of the tumor microenvironment in cancer therapy: unveiling new targets to overcome drug resistance

Cancer is a leading cause of death globally, with resistance to therapy representing a major obstacle to effective treatment. The tumor microenvironment (TME), comprising a complex network to cellular and non-cellular components including cancer-associated fibroblasts, immune cells, the extracellular matrix and region of hypoxia, is integral to cancer progression and therapeutic resistance. This review delves into the multifaceted interactions within the TME that contribute to tumor growth, survival and immune evasion. Key elements such as the role of cancer- associated fibroblasts in remodeling the extracellular matrix and promoting angiogenesis, the influence of immune cells such as tumor-associated macrophages in creating an immunosuppressive milieu and the impact of hypoxia conditions on metabolic adaptation and therapy resistance are thoroughly examined. This review evaluates current and emerging TME-targeted therapeutic strategies, including inhibitors of extracellular matrix components, modulators of immune cell activity and approached to alleviate hypoxia. Combination therapies that integrate TME-targeted agents with conventional treatments such as chemotherapy and immunotherapy are also discussed for their potential to enhance treatment efficacy and circumvent resistance mechanisms. By synthesising recent advances in TME research and therapeutic innovation, this paper aims to underscore the importance of TME in cancer therapy and highlight promising avenues for improving patient outcomes through targeted intervention.

Integrin signaling in tumor biology: mechanisms of intercellular crosstalk and emerging targeted therapies

Integrins, a family of transmembrane cell adhesion receptors, mediate intercellular and cell-extracellular matrix crosstalk via outside-in and inside-out signaling pathways. Integrins, categorized into 24 distinct combinations of α and β subunits, exhibit tissue-specific expression and perform unique or overlapping roles in physiological and pathophysiological processes. These roles encompass embryonic angiogenesis, tissue repair, and the modulation of tumor cell angiogenesis, progression, invasion, and metastasis. Notably, integrins are significant contributors to tumor development, offering valuable insights into the potential of integrin-targeted diagnostics and therapeutics. Currently, there are various preclinical and clinical trials aiming to harness integrin antagonists that are safe, efficacious, and exhibit low toxicity. Owing to the functional redundancy across integrin types and the complexity of the mechanisms of integrin-mediated multiple key processes associated with tumor biology, challenges exist that impede advancements in integrin-targeted therapy. Nevertheless, innovative strategies focused on integrin modulation represent significant breakthroughs for improving patient care and promoting comprehensive insights into the underlying mechanisms of tumor biology. This review elucidates the impact of integrins on three distinct cell types in multiple key processes associated with tumor biology and explores the emerging integrin-targeted therapeutic approaches for the treatment of tumors, which will provide ideas for optimal therapeutic approaches in the future.

Frizzled receptors: gatekeepers of Wnt signaling in development and disease

Frizzled (FZD) receptors are a subset of G-protein-coupled receptors (GPCRs), the largest class of human cell surface receptors and a major target of FDA-approved drugs. Activated by Wnt ligands, FZDs regulate key cellular processes such as proliferation, differentiation, and polarity, positioning them at the intersection of developmental biology and disease, including cancer. Despite their significance, FZD signaling remains incompletely understood, particularly in distinguishing receptor-specific roles across canonical and non-canonical Wnt pathways. Challenges include defining ligand-receptor specificity, elucidating signal transduction mechanisms, and understanding the influence of post translational modifications and the cellular context. Structural dynamics, receptor trafficking, and non-canonical signaling contributions also remain areas of active investigation. Recent advances in structural biology, transcriptomics, and functional genomics are beginning to address these gaps, while emerging therapeutic approaches-such as small-molecule modulators and antibodies-highlight the potential of FZDs as drug targets. This review synthesizes current insights into FZD receptor biology, examines ongoing controversies, and outlines promising directions for future research and therapeutic development.

Stiffening of a fibrous matrix after recovery of contracted inclusions

Disordered fibrous matrices in living tissues are subjected to forces exerted by cells that contract to pull on matrix fibers. To maintain homeostasis or facilitate disease progression, contracted cells often push on matrix fibers as they recover their original sizes. Recent advances have shown that matrix geometry encodes loading history into mechanical memory independently of plasticity mechanisms such as inter-fiber cohesion or fiber yielding. Conceptualizing cells as inclusions undergoing sequential contraction and recovery, prior work documented matrix remodeling surrounding a solitary recovered inclusion. However, because the remodeling induced by the contraction of multiple inclusions differs from that caused by a single contracted inclusion, we investigate how matrix remodeling occurs when multiple contracted inclusions recover simultaneously, a scenario that more accurately reflects real tissues containing many closely spaced cells. Using mechanics-based computational models of fibrous matrices embedded with clusters of inclusions, we studied the mechanical remodeling of the matrix during the simultaneous recovery of inclusions after contraction. The results revealed permanent mechanical remodeling of the matrix within the cluster, with stiffening observed in areas of the matrix enclosed by closely spaced inclusions. This stiffening was driven by microstructural changes in matrix geometry and was corroborated in experiments, where collagen matrices permanently remodeled by the contraction and recovery of closely spaced embedded cells also exhibited stiffening. By enriching the understanding of memory formation in fibrous matrices, this study opens new possibilities for estimating cell forces on matrix substrates and refining metamaterial design strategies.

Matrix Stiffness Regulates Mechanotransduction and Vascular Network Formation of hiPSC-Derived Endothelial Progenitors Encapsulated in 3D Hydrogels

The mechanical properties of the extracellular matrix (ECM), particularly stiffness, regulate endothelial progenitor responses during vascular development, yet their behavior in physiologically compliant matrices (<1 kPa) remains underexplored. Using norbornene-modified hyaluronic acid (NorHA) hydrogels with tunable stiffness (190-884 Pa), we investigated how hydrogel stiffness influences cell morphology, endothelial maturation, mechanotransduction, and microvascular network formation in human induced pluripotent stem cell-derived endothelial progenitors (hiPSC-EPs). Our findings reveal a stiffness-dependent tradeoff between mechanotransduction and vascular network formation. At intermediate stiffness (551 Pa), cells exhibited the greatest increase in endothelial marker CD31 expression and Yes-associated protein (YAP)/ transcriptional coactivator with PDZ-binding motif (TAZ) nuclear translocation, indicating enhanced mechanotransduction and endothelial maturation. However, this did not translate to superior plexus formation. Instead, the most compliant matrix (190 Pa) supported greater vascular connectivity, characterized by longer branches (∼0.03/volume vs. 0.015 at 551 Pa) and enhanced actin remodeling. 3D cell contraction measurements revealed a 15.6-fold higher basal displacement in compliant hydrogels, suggesting that cell-generated forces and matrix deformability collectively drive vascular morphogenesis. Unlike prior studies focusing on pathological stiffness ranges (>10 kPa), our results emphasize that vascularization is not solely driven by the most mechanotransductive environment but rather by a balance of compliance, contractility, and cell-induced remodeling. These findings underscore the need to design hydrogels that provide sufficient mechanotransduction for endothelial maturation while maintaining compliance to support dynamic vascular morphogenesis. This work provides a mechanically tuned framework for optimizing microenvironments to balance endothelial differentiation and vascular network formation in tissue engineering and regenerative medicine.

Filamented light (FLight) biofabrication of mini-tendon models show tunable matrix confinement and nuclear morphology

One hallmark of healthy tendon tissue is the high confinement of tenocytes between tightly packed, highly aligned collagen fibers. During tendinopathy, this organization becomes dysregulated, leading to cells with round-shaped morphology and collagen fibers which exhibit crimping and misalignment. The elongated nuclei in healthy tendons are linked to matrix homeostasis through distinct mechanotransduction pathways, and it is believed that the loss of nuclear confinement could upregulate genes associated with abnormal matrix remodeling. Replicating the cell and nuclear morphology of healthy and diseased states of tendon, however, remains a significant challenge for engineeredin vitrotendon models. Here we report on a high throughput biofabrication of mini-tendons that mimick the tendon core compartment based on the filamented light (FLight) approach. Each mini-tendon, with a length of 4 mm, was composed of parallel hydrogel microfilaments (2-5µm diameter) and microchannels (2-10µm diameter) that confined the cells. We generated four distinct matrices with varying stiffness (7-40 kPa) and microchannel dimensions. After 14 d of culture, 29% of tenocytes in the softest matrix with the largest microchannel diameter were aligned, exhibiting an average nuclear aspect ratio (nAR) of 2.1. In contrast, 84% of tenocytes in the stiffest matrix with the smallest microchannel diameter were highly aligned, with a mean nAR of 3.4. When tenocytes were culturedonthe FLight hydrogels (2D) as opposed to within the hydrogels three-dimensional (3D), the mean nAR was less than 1.9, indicating that nuclear morphology is significantly more confined in 3D environments. By tuning the stiffness and microarchitecture of the FLight matrix, we demonstrated that mechanical confinement can be modulated to exert control over the extent of nuclear confinement. This high-throughput, tunable platform offers a promising approach for studying the mechanobiology of healthy and diseased tendons and for eventual testing of drug compounds against tendinopathy.

Transient Receptor Potential Channels in Prostate Cancer: Associations with ERG Fusions and Survival

Calcium movement and concentration in the cell plays significant roles in normal physiology and in diseases such as cancer. The significance of this ion in oncogenesis suggests that membrane-relevant proteins are involved in its regulation and are deregulated in various cancers. These channels and transporters could be targets for therapeutic interventions. An evaluation of the expression of transient receptor potential (TRP) channels in prostate cancer was performed using publicly available genomic and proteome data. Two TRP family members with high expression in prostate cancers, TRPML2 and TRPM4, were chosen for further analysis the uncover the associations of their level of expression with clinical and pathologic prostate cancer characteristics. Several TRP channels were expressed in prostate cancers at the protein level including TRPM4, TRPML1, TRPML2, TRPC1 and TRPP3. At the mRNA level, MCOLN2 and TRPM4 were strongly expressed in a sub-set of prostate cancers. Cases with high MCOLN2 mRNA expression were associated with frequent ERG fusions and a trend for better survival outcomes. In contrast, prostate cancer cases with high TRPM4 mRNA expression were associated with lower ERG fusion frequency than cases with low TRPM4 mRNA expression. The prognosis of prostate cancers with high TRPM4 expression was not different from the prognosis with counterparts having low TRPM4 mRNA expression. TRP channels were expressed in sub-sets of prostate cancers. The two well-expressed channels of the super family, TRPML2 and TRPM4, have divergent associations with the most prevalent prostate cancer molecular aberrations, ERG fusions. These results imply diverse regulations of the TRP channels that would have to be taken into consideration when devising therapeutic interventions targeting individual channels.

High matrix stiffness promotes senescence of type II alveolar epithelial cells by lysosomal degradation of lamin A/C in pulmonary fibrosis

BACKGROUND

Cellular senescence is one of the key steps in the progression of pulmonary fibrosis, and the senescence of type II alveolar epithelial cells (AEC IIs) may potentially accelerate the progression of pulmonary fibrosis. However, the molecular mechanisms underlying cellular senescence in pulmonary fibrosis remain unclear.

METHODS

The researchers first conducted in vitro experiments to investigate whether AEC IIs cultured on high matrix stiffness would lead to cellular senescence. Next, samples from mouse pulmonary fibrosis models and clinical idiopathic pulmonary fibrosis (IPF) patients were tested to observe extracellular matrix deposition, lamin A/C levels, and cellular senescence status in lung tissue. Construct lamin A/C knockdown and overexpression systems separately in AEC IIs, and observe whether changes in lamin A/C levels lead to cellular senescence. Further explore the degradation mechanism of lamin A/C using protein degradation inhibitors.

RESULTS

In vitro experiments have found that high matrix stiffness promotes senescence of AEC IIs. In a mouse model of pulmonary fibrosis, AEC IIs were found to exhibit significant cellular senescence on day 21. In clinical IPF samples, it was found that senescent cells expressed low levels of lamin A/C. In the lamin A/C SiRNA knockdown system, it was further confirmed that AEC IIs with low levels of lamin A/C are more prone to cellular senescence. Under high matrix stiffness, lamin A/C in AEC IIs is degraded through the autophagy lysosome pathway. The use of chloroquine can effectively alleviate cellular senescence.

CONCLUSIONS

High matrix stiffness degrades lamin A/C in pulmonary fibrosis through lysosomal degradation pathways, promoting AEC II senescence. Inhibition the degradation of lamin A/C could alleviate AEC II senescence.

Mechanical signal-mediated mitochondria-endoplasmic reticulum contacts modulate Leydig cell testosterone biosynthesis during testis development

In males, 95% of testosterone is synthesized by Leydig cells, and a deficiency in this synthesis will cause metabolic disorders and multiple organ dysfunction. Testosterone deficiency is not only affected by aged or diseased Leydig cells, which have been studied extensively, but is also closely related to the development of the testis. At present, the focus on the mechanism of testis development includes epigenetic and hormone regulation. However, testicular development is constrained by the external tough tunica albuginea, suggesting that mechanical signals may also play an important role in the regulation of testis development; however, this is not yet well understood. In this in vitro study, we found that a gradual increase in extracellular substrate stiffness for testis development leads to the activation of mechanical signals to promote cytoskeleton remodeling. Eventually, the mechanical signal mediates changes in the mitochondrial-endoplasmic reticulum and affects the synthesis of testosterone in Leydig cells. Through organoid and animal experiments, we found that targeting mechanical signaling pathways that regulate testosterone biosynthesis is feasible. This provides a new angle for further exploration of testis development and new insights into how substrate stiffness affects the testis, raising new clues for clinical applications.

Gravitational forces and matrix stiffness modulate the invasiveness of breast cancer cells in bioprinted spheroids

The progression of breast cancer is influenced by the stiffness of the extracellular matrix (ECM), which becomes stiffer as cancer advances due to increased collagen IV and laminin secretion by cancer-associated fibroblasts. Intriguingly, breast cancer cells cultivated in two-dimensions exhibit a less aggressive behavior when exposed to weightlessness, or microgravity conditions. This study aims to elucidate the interplay between matrix stiffness and microgravity on breast cancer progression. For this purpose, three-dimensional spheroids of breast cancer cell lines (MCF-7 and MDA-MB-231) were formed. These spheroids were subsequently bioprinted in hydrogels of varying stiffness, obtained by the mixing of gelatin methacrylate and poly(ethylene) glycol diacrylate mixed at different ratios. The constructs were printed with a custom stereolithography (SLA) bioprinter converted from a low-cost, commercially available 3D printer. These bioprinted structures, encapsulating breast cancer spheroids, were then placed in a clinostat (microgravity simulation device) for a duration of seven days. Comparative analyses were conducted between objects cultured under microgravity and standard earth gravity conditions. Protein expression was characterized through fluorescent microscopy, while gene expression of MCF-7 constructs was analyzed via RNA sequencing. Remarkably, the influence of a stiffer ECM on the protein and gene expression levels of breast cancer cells could be modulated and sometimes even reversed in microgravity conditions. The study's findings hold implications for refining therapeutic strategies for advanced breast cancer stages - an array of genes involved in reversing aggressive or even metastatic behavior might lead to the discovery of new compounds that could be used in a clinical setting.

Nanomechanical characterization of soft nanomaterial using atomic force microscopy

Atomic force microscopy (AFM) is a promising method for generating high-spatial-resolution images, providing insightful perspectives on the nanomechanical attributes of soft matter, including cells, bacteria, viruses, proteins, and nanoparticles. AFM is widely used in biological and pharmaceutical sciences because it can scrutinize mechanical properties under physiological conditions. We comprehensively reviewed experimental techniques and fundamental mathematical models to investigate the mechanical properties, including elastic moduli and binding forces, of soft materials. To determine these mechanical properties, two-dimensional arrays of force-distance (f-d) curves are obtained through AFM indentation experiments using the force volume technique. For elasticity determination, models are divided into approach f-d curve-based models, represented by the Hertz model, and retract f-d curve-based models, exemplified by the Johnson-Kendall-Roberts and Derjaguin-Müller-Toporov models. Especially, the Chen, Tu, and Cappella models, developed from the Hertz model, are used for thin samples on hard substrates. Additionally, the establishment of physical or chemical bonds during indentation experiments, observable in retract f-d curves, is crucial for the adhesive properties of samples and binding affinity between antibodies (receptors) and antigens (ligands). Chemical force microscopy, single-molecule force spectroscopy, and single-cell force spectroscopy are primary AFM methods that provide a comprehensive view of such properties through retract curve analysis. Furthermore, this paper, structured into key thematic sections, also reviews the exemplary application of AFM across multiple scientific disciplines. Notably, cancer cells are softer than healthy cells, although more sophisticated investigations are required for prognostic applications. AFM also investigates how bacteria adapt to antibiotics, addressing antimicrobial resistance, and reveals that stiffer virus capsids indicate reduced infectivity, aiding in the development of new strategies to combat viral infections. Moreover, AFM paves the way for innovative therapeutic approaches in designing effective drug delivery systems by providing insights into the physical properties of soft nanoparticles and the binding affinity of target moieties. Our review provides researchers with representative studies applying AFM to a wide range of cross-disciplinary research.

Mimicking the Complexity of Solid Tumors: How Spheroids Could Advance Cancer Preclinical Transformative Approaches

Traditional 2D cell culture models present significant limitations in replicating the intricate architecture and microenvironment of in vivo solid tumors, which are essential for accurately studying cancer initiation, growth, progression, and metastasis. This underscores the need for the development of advanced preclinical models to accelerate research outcomes. Emerging 3D cell culture systems, particularly spheroid models, provide a more realistic representation of solid tumor properties by capturing the complex interactions occurring within the tumor microenvironment, including the extracellular matrix dynamics that influence cancer progression. Among solid tumors, breast cancer remains the most frequently diagnosed cancer among women globally and a leading cause of cancer-related mortality. Here we emphasize the value of breast cancer cell-derived spheroids in revealing differential molecular characteristics and understanding cancer cell properties during the early stages of invasion into adjacent tissues. Conclusively, this study underscores the urgent need to adopt 3D cell culture platforms, given their significant contributions to advanced cancer research and pharmaceutical targeting. This may well offer a transformative approach for preclinical studies and enhance our ability to test therapeutic efficiency in conditions that closely mimic the growth and progression of in vivo solid tumors.

Breast cancer extracellular matrix invasion depends on local mechanical loading of the collagen network

Active mechanical stresses in and around tumors affect cancer cell behavior and independently regulate cancer progression. To investigate the role of mechanical stress in breast cancer cell invasion, magnetic alginate beads loaded with iron oxide nanoparticles were coated with MDA-MB-231 breast cancer cells and embedded in a three-dimensional extracellular matrix (ECM) model subjected to an external magnetic field during culture. Bead displacement, cell shape and patterns of invasion of the collagen gel, and cell proliferation were assessed over 7 days of culture. The alginate beads swelled over the first 24 h in culture, creating circumferential stress akin to that created by tumor growth, while bead magnetic properties enabled local mechanical loading (compression, tension, and relaxation) and motion within the in vitro tissue constructs upon exposure to an external magnetic field. Beads displaced 0.2-1.6 mm through the collagen gels, depending on magnet size and distance, compressing the collagen network microstructure without gel mechanical failure. Invading cells formed a spatulate pattern as they moved into the compressed ECM region, with individual cells aligned parallel to the bead surface. During the first 24 hours of compressive magnetic force loading, invading cancer cells became round, losing elongation and ability to invade out from the bead surface, while still actively dividing. In contrast, cell invasion in unloaded constructs and in loaded constructs away from the compression region invaded as single cells, transversely outward from the bead surface. Finally, cell proliferation was 1.3× higher only after external magnet removal, which caused relaxation of mechanical stress in the collagen network. These findings indicate effects on breast cancer invasion of mechanical loading of ECM, both from compressive loading and from load relaxation. Findings point to the influence of mechanical stress on cancer cell behavior and suggest that relaxing mechanical stress in and around a tumor may promote cancer progression through higher proliferation and invasion.

Analytical methods in studying cell force sensing: principles, current technologies and perspectives

Mechanical stimulation plays a crucial role in numerous biological activities, including tissue development, regeneration and remodeling. Understanding how cells respond to their mechanical microenvironment is vital for investigating mechanotransduction with adequate spatial and temporal resolution. Cell force sensing-also known as mechanosensation or mechanotransduction-involves force transmission through the cytoskeleton and mechanochemical signaling. Insights into cell-extracellular matrix interactions and mechanotransduction are particularly relevant for guiding biomaterial design in tissue engineering. To establish a foundation for mechanical biomedicine, this review will provide a comprehensive overview of cell mechanotransduction mechanisms, including the structural components essential for effective mechanical responses, such as cytoskeletal elements, force-sensitive ion channels, membrane receptors and key signaling pathways. It will also discuss the clutch model in force transmission, the role of mechanotransduction in both physiology and pathological contexts, and biomechanics and biomaterial design. Additionally, we outline analytical approaches for characterizing forces at cellular and subcellular levels, discussing the advantages and limitations of each method to aid researchers in selecting appropriate techniques. Finally, we summarize recent advancements in cell force sensing and identify key challenges for future research. Overall, this review should contribute to biomedical engineering by supporting the design of biomaterials that integrate precise mechanical information.

Comparative Analysis of 3D Culture Methodologies in Prostate Cancer Cells

Three-dimensional (3D) cell culture models are increasingly utilized in cancer research to better replicate in vivo tumor microenvironments. This study examines the effects of different 3D scaffolding materials, including Matrigel, GelTrex, and the plant-based GrowDex, on prostate cancer cell lines, with a particular emphasis on neuroendocrine prostate cancer (NEPC). Four cell lines (LNCaP, LASCPC-01, PC-3, and KUCaP13) were cultured in these scaffolds to evaluate spheroid formation, cell viability, and gene expression. The results revealed that while all scaffolds supported cell viability, spheroid formation varied significantly: Matrigel promoted the most robust spheroids, especially for LASCPC-01, whereas GrowDex exhibited limitations for certain cell lines. Gene expression analysis indicated a consistent reduction in androgen receptor (AR) expression in LNCaP cells across all scaffolds, suggesting a potential shift towards a neuroendocrine phenotype. However, the expression of neuroendocrine markers varied depending on the scaffold and culture method, with the mini-domes method in Matrigel leading to decreased expression of both castration-resistant prostate cancer (CRPC) and NEPC markers. These findings highlight the scaffold-dependent variability in 3D culture outcomes and emphasize the need for standardized methodologies to ensure consistency and relevance in prostate cancer research.

Harnessing phytochemicals: Innovative strategies to enhance cancer immunotherapy

Cancer immunotherapy has revolutionized cancer treatment, but therapeutic ineffectiveness-driven by the tumor microenvironment and immune evasion mechanisms-continues to limit its clinical efficacy. This challenge underscores the need to explore innovative approaches, such as multimodal immunotherapy. Phytochemicals, bioactive compounds derived from plants, have emerged as promising candidates for overcoming these barriers due to their immunomodulatory and antitumor properties. This review explores the synergistic potential of phytochemicals in enhancing immunotherapy by modulating immune responses, reprogramming the tumor microenvironment, and reducing immunosuppressive factors. Integrating phytochemicals with conventional immunotherapy strategies represents a novel approach to mitigating resistance and enhancing therapeutic outcomes. For instance, nab-paclitaxel has shown the potential in overcoming resistance to immune checkpoint inhibitors, while QS-21 synergistically enhances the efficacy of tumor vaccines. Furthermore, we highlight recent advancements in leveraging nanotechnology to engineer phytochemicals for improved bioavailability and targeted delivery. These innovations hold great promise for optimizing the clinical application of phytochemicals. However, further large-scale clinical studies are crucial to fully integrate these compounds into immunotherapeutic regimens effectively.

Contrast agent dispersion visualized by CE-EUS may be a prediction tool for FOLFIRINOX chemotherapy effectiveness in patients with pancreatic adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) still has a dismal 5-year overall survival of 13 %. Chemotherapy is increasingly used as treatment in both (neo-) adjuvant and palliative conditions. However, the overall survival benefits of chemotherapy must be weighed against significant side effects leading to a reduction in quality of life. CE-EUS and elastography could provide additional information about the vascularization and elasticity of the pancreatic tumor. The aim of this study was to investigate if contrast-enhanced endoscopic ultrasound and/or elastography could be suitable to predict the effectiveness of FOLFIRINOX.

METHODS

Single center, prospective proof-of-concept study in which intravenous contrast agent was administered and strain ratio was calculated in patients undergoing EUS in their regular diagnostic work-up. Directly after contrast administration, a video of 120 s was recorded and afterwards tracked and fitted by a Modified Local Density Random Walk (mLDRW) model.

RESULTS

We included 17 patients. Based on cross-sectional imaging based RECIST criteria, chemotherapy treatment was effective in 11 patients and not effective in 6 patients. The contrast dispersion parameter (κ1) differed significantly between both groups in favor of the responders: 2.994 (IQR 1.670-5.170) vs 1.203 (IQR 0.953-1.756), p = 0.005. The elastography strain ratio was higher in the effectively treated group (20.9 vs 13.6, p = 0.138).

CONCLUSION

This proof-of-concept study showed that the dispersion parameter of the first wave of contrast was 2.5 times higher in patients in whom FOLFIRINOX was effective, suggesting that this parameter could possibly be a reliable prediction tool.

The first embryo, the origin of cancer and animal phylogeny. V. Cancer stem cells as the unifying biomechanical principle between embryology and oncology

The role of embryology in metazoan evolution is rooted deeply in the history of science. Viewing Neoplasia as an evolutionary engine provides a scientific basis for reexamining the disease cancer. Once the embryo is understood as a benign tumor with a pivotal role in the evolution of all animal forms, there will be an immediate paradigm shift in the search for cancer cure, potentially revealing insights that may be buried within the great developmental transitions of metazoans. This article discusses one of the unifying principles between embryology and oncology, namely cancer stem cells. Some considerations are also provided on the central role of physics and biomechanics in the assembly of the first embryo, which can be regarded as a differentiated benign tumor. Mechanical impregnation of the nucleus of a stem cell, culminating in a totipotent/multipotent cell, was a major event safeguarding the success of embryogenesis throughout evolution. Germ cells in the earliest ctenophore embryos underwent delayed differentiation, subsequent to the mechanical assembly of the embryo. Finally, a discussion is presented on the concept that cancer and embryogenesis (cancer and healthy stem cells) are two sides of the same coin, that is, of the same process. The only difference is that cancer stem cells reveal themselves in inappropriate contexts. Neoplasia is a free force, whereas cancer is a force contained by animal organization.

Design and characterization of an optical phantom for mesoscopic multimodal fluorescence lifetime imaging and optical coherence elastography

We developed a novel methodology for manufacturing multimodal, tissue-mimicking phantoms that exhibit both molecular and biomechanical contrast. This methodology leverages the immiscibility of silicone and hydrogels to create solid mesoscale phantoms with localized regions of precisely controlled fluorescence, including fluorescence lifetime properties, and adjustable stiffness, without requiring physical barriers. Mechanical, fluorescent, and optical characterization confirmed the tunability of the phantoms across a range of values relevant to biomedical applications. A macroscale 3D phantom was fabricated, and its properties were validated through fluorescence lifetime imaging (FLI) and optical coherence elastography (OCE). Validation demonstrated the successful tuning of both mechanical and fluorescence lifetime contrasts within a 3D structure, highlighting the feasibility of multimodal FLI-OCE. This new phantom manufacturing process is expected to support the development and validation of new multimodal imaging approaches to study molecular and biomechanical properties of the tumor microenvironment (TME), as well as their impact on therapeutic efficacy, and to enhance targeted therapies.

Increased Matrix Stiffness Promotes Slow Muscle Fibre Regeneration After Skeletal Muscle Injury

The global prevalence of skeletal muscle diseases has progressively escalated in recent years. This study aimed to explore the potential role of matrix stiffness in the repair mechanisms following skeletal muscle injury. We observed an increase in muscle stiffness, a significant rise in the number of type I muscle fibres and a notable elevation in mRNA expression levels of Myh7/2 alongside a decrease in Myh1/4 on day 3 post tibialis anterior muscle injury. To replicate these in vivo changes, C2C12 cells were cultured under high matrix stiffness conditions, and compared to those on low matrix stiffness, the C2C12 cells cultured on high matrix stiffness showed increased expression levels of Myh7/2 mRNA and production levels of MYH7/2, indicating differentiation into slow-twitch muscle fibre types. Furthermore, up-regulation of DRP1 phosphorylation along with elevated F-actin fluorescence intensity and RHOA and ROCK1 production indicates that high matrix stiffness induces cytoskeletal remodelling to regulate mitochondrial fission processes. Our data also revealed up-regulation in mRNA expression level for Actb, phosphorylation level for DRP1, mitochondrial quantity and MYH7/2 production level. Importantly, these effects were effectively reversed by the application of ROCK inhibitor Y-27632, highlighting that targeting cytoskeletal dynamics can modulate myogenic differentiation pathways within C2C12 cells. These findings provide valuable insights into how matrix stiffness influences fibre type transformation during skeletal muscle injury repair while suggesting potential therapeutic targets for intervention.

Matrix Stiffness-Mediated DNA Methylation in Endothelial Cells

Purpose

Altered tissue mechanics is a prominent feature of many pathological conditions including cancer. As such, much work has been dedicated to understanding how mechanical features of tissues contribute to pathogenesis. Interestingly, previous work has demonstrated that the tumor vasculature acquires pathological features in part due to enhanced tumor stiffening. To further understand how matrix mechanics may be translated into altered cell behavior and ultimately affect tumor vasculature function, we have investigated the effects of substrate stiffening on endothelial epigenetics. Specifically, we have focused on DNA methylation as recent work indicates DNA methylation in endothelial cells can contribute to aberrant behavior in a range of pathological conditions.

Methods

Human umbilical vein endothelial cells (HUVECs) were seeded on stiff and compliant collagen-coated polyacrylamide gels and allowed to form monolayers over 5 days. DNA methylation was assessed via 5-methylcytosine ELISA assays and immunofluorescent staining. Gene expression was assessed via qPCR on RNA isolated from HUVECs seeded on collagen-coated polyacrylamide gels of varying stiffness.

Results

Our work demonstrates that endothelial cells cultured on stiffer substrates exhibit lower levels of global DNA methylation relative to endothelial cells cultured on more compliant substrates. Interestingly, gene expression and DNA methylation dynamics suggest stiffness-mediated gene expression may play a role in establishing or maintaining differential DNA methylation levels in addition to enzyme activity. Additionally, we found that the process of passaging induced higher levels of global DNA methylation.

Conclusions

Altogether, our results underscore the importance of considering cell culture substrate mechanics to preserve the epigenetic integrity of primary cells and obtain analyses that recapitulate the primary environment. Furthermore, these results serve as an important launching point for further work studying the intersection tissue mechanics and epigenetics under pathological conditions.

Leveraging computational modeling to explore epithelial and endothelial cell monolayer mechanobiology

Endothelial cells (ENCs) and epithelial cells (EPCs) form monolayers whose barrier function is critical for the maintenance of physiological processes and extremely sensitive to mechanical cues. Computational models have emerged as powerful tools to elucidate how mechanical cues impact the behavior of these monolayers in health and disease. Herein, the importance of mechanics in regulating ENC and EPC monolayer behavior is established, highlighting similarities and differences in various biological contexts. Concurrently, computational approaches and their importance in accelerating mechanobiology studies are discussed, emphasizing their limitations and suggesting future directions. The aim is to inspire further synergies between cell biologists and modelers, which are crucial for accelerating cell mechanobiology research.

Forcing the code: tension modulates signaling to drive morphogenesis and malignancy

Development and disease are regulated by the interplay between genetics and the signaling pathways stimulated by morphogens, growth factors, and cytokines. Experimental data highlight the importance of mechanical force in regulating embryonic development, tissue morphogenesis, and malignancy. Force not only sculpts tissue movements to drive embryogenesis and morphogenesis but also modifies the context of biochemical signaling and gene expression to regulate cell and tissue fate. Not surprisingly, experiments have demonstrated that perturbations in cell tension drive malignancy and metastasis by altering biochemical signaling and gene expression through modifications in cytoskeletal tension, transmembrane receptor structure and function, and organelle phenotype that enhance cell growth and survival, alter metabolism, and foster cell migration and invasion. At the tissue level, tumor-associated forces disrupt cell-cell adhesions to perturb tissue organization, compromise vascular integrity to induce hypoxia, and interfere with antitumor immunity to foster metastasis and treatment resistance. Exciting new approaches now exist with which to clarify the relationship between mechanotransduction, biochemical signaling, and gene expression in development and disease. Indeed, gaining insight into these interactions is essential to unravel molecular mechanisms that regulate development and clarify the molecular basis of cancer.

Insights into the mechanisms, regulation, and therapeutic implications of extracellular matrix stiffness in cancer

The tumor microenvironment (TME) is critical for cancer initiation, growth, metastasis, and therapeutic resistance. The extracellular matrix (ECM) is a significant tumor component that serves various functions, including mechanical support, TME regulation, and signal molecule generation. The quantity and cross-linking status of ECM components are crucial factors in tumor development, as they determine tissue stiffness and the interaction between stiff TME and cancer cells, resulting in aberrant mechanotransduction, proliferation, migration, invasion, angiogenesis, immune evasion, and treatment resistance. Therefore, broad knowledge of ECM dysregulation in the TME might aid in developing innovative cancer therapies. This review summarized the available information on major ECM components, their functions, factors that increase and decrease matrix stiffness, and related signaling pathways that interplay between cancer cells and the ECM in TME. Moreover, mechanotransduction alters during tumorogenesis, and current drug therapy based on ECM as targets, as well as future efforts in ECM and cancer, are also discussed.

Prediction of tumor regression grade in far-advanced gastric cancer after preoperative immuno-chemotherapy using dual-energy CT-derived extracellular volume fraction

OBJECTIVES

This study examines the effectiveness of dual-energy CT (DECT) delayed-phase extracellular volume (ECV) fraction in predicting tumor regression grade (TRG) in far-advanced gastric cancer (FAGC) patients receiving preoperative immuno-chemotherapy.

MATERIALS AND METHODS

A retrospective analysis was performed on far-advanced gastric adenocarcinoma patients treated with preoperative immuno-chemotherapy at our institution from August 2019 to March 2023. Patients were categorized based on their TRG into pathological complete response (pCR) and non-pCR groups. ECV was determined using the delayed-phase iodine maps. In addition, tumor iodine densities and standardized iodine ratios were meticulously analyzed using the triple-phase enhanced iodine maps. Univariate analysis with five-fold cross-validation and Spearman correlation determined DECT parameters and clinical indicators association with pCR. The predictive accuracy of these parameters for pCR was evaluated using a weighted logistic regression model with five-fold cross-validation.

RESULTS

Of the 88 patients enrolled (mean age 60.8 ± 11.1 years, 63 males), 21 (23.9%) achieved pCR. Univariate analysis indicated ECV's significant role in differentiating between pCR and non-pCR groups (average p value = 0.021). In the logistic regression model, ECV independently predicted pCR with an average odds ratio of 0.911 (95% confidence interval, 0.798-0.994). The model, incorporating ECV, tumor area, and IDAV (the relative change rate of iodine density from venous phase to arterial phase), showed an average area under curves (AUCs) of 0.780 (0.770-0.791) and 0.766 (0.731-0.800) for the training and validation sets, respectively, in predicting pCR.

CONCLUSION

DECT-derived ECV fraction is a valuable predictor of TRG in FAGC patients undergoing preoperative immuno-chemotherapy.

CLINICAL RELEVANCE STATEMENT

This study demonstrates that DECT-derived extracellular volume fraction is a reliable predictor for pathological complete response in far-advanced gastric cancer patients receiving preoperative immuno-chemotherapy, offering a noninvasive tool for identifying potential treatment beneficiaries.

PIEZO1 mediates matrix stiffness-induced tumor progression in kidney renal clear cell carcinoma by activating the Ca2+/Calpain/YAP pathway

OBJECTIVE

The significance of physical factors in the onset and progression of tumors has been increasingly substantiated by a multitude of studies. The extracellular matrix, a pivotal component of the tumor microenvironment, has been the subject of extensive investigation in connection with the advancement of KIRC (Kidney Renal Clear Cell Carcinoma) in recent years. PIEZO1, a mechanosensitive ion channel, has been recognized as a modulator of diverse physiological processes. Nonetheless, the precise function of PIEZO1 as a transducer of mechanical stimuli in KIRC remains poorly elucidated.

METHODS

A bioinformatics analysis was conducted using data from The Cancer Genome Atlas (TCGA) and the Clinical Proteomic Tumor Analysis Consortium (CPTAC) to explore the correlation between matrix stiffness indicators, such as COL1A1 and LOX mRNA levels, and KIRC prognosis. Expression patterns of mechanosensitive ion channels, particularly PIEZO1, were examined. Collagen-coated polyacrylamide hydrogel models were utilized to simulate varying stiffness environments and study their effects on KIRC cell behavior in vitro. Functional experiments, including PIEZO1 knockdown and overexpression, were performed to investigate the molecular mechanisms underlying matrix stiffness-induced cellular changes. Interventions in the Ca2+/Calpain/YAP Pathway were conducted to evaluate their effects on cell growth, EMT, and stemness characteristics.

RESULTS

Our findings indicate a significant correlation between matrix stiffness and the prognosis of KIRC patients. It is observed that higher mechanical stiffness can facilitate the growth and metastasis of KIRC cells. Notably, we have also observed that the deficiency of PIEZO1 hinders the proliferation, EMT, and stemness characteristics of KIRC cells induced by a stiff matrix. Our study suggests that PIEZO1 plays a crucial role in mediating KIRC growth and metastasis through the activation of the Ca2+/Calpain/YAP Pathway.

CONCLUSION

This study elucidates a novel mechanism through which the activation of PIEZO1 leads to calcium influx, subsequent calpain activation, and YAP nuclear translocation, thereby contributing to the progression of KIRC driven by matrix stiffness.

Targeting the lung tumour stroma: harnessing nanoparticles for effective therapeutic interventions

Lung cancer remains an influential global health concern, necessitating the development of innovative therapeutic strategies. The tumour stroma, which is known as tumour microenvironment (TME) has a central impact on tumour expansion and treatment resistance. The stroma of lung tumours consists of numerous cells and molecules that shape an environment for tumour expansion. This environment not only protects tumoral cells against immune system attacks but also enables tumour stroma to attenuate the action of antitumor drugs. This stroma consists of stromal cells like cancer-associated fibroblasts (CAFs), suppressive immune cells, and cytotoxic immune cells. Additionally, the presence of stem cells, endothelial cells and pericytes can facilitate tumour volume expansion. Nanoparticles are hopeful tools for targeted drug delivery because of their extraordinary properties and their capacity to devastate biological obstacles. This review article provides a comprehensive overview of contemporary advancements in targeting the lung tumour stroma using nanoparticles. Various nanoparticle-based approaches, including passive and active targeting, and stimuli-responsive systems, highlighting their potential to improve drug delivery efficiency. Additionally, the role of nanotechnology in modulating the tumour stroma by targeting key components such as immune cells, extracellular matrix (ECM), hypoxia, and suppressive elements in the lung tumour stroma.

Towards a more objective and high-throughput spheroid invasion assay quantification method

Multicellular spheroids embedded in 3D hydrogels are prominent in vitro models for 3D cell invasion. Yet, quantification methods for spheroid cell invasion that are high-throughput, objective and accessible are still lacking. Variations in spheroid sizes and the shapes of the cells within render it difficult to objectively assess invasion extent. The goal of this work is to develop a high-throughput quantification method of cell invasion into 3D matrices that minimizes sensitivity to initial spheroid size and cell spreading and provides precise integrative directionally-dependent metrics of invasion. By analyzing images of fluorescent cell nuclei, invasion metrics are automatically calculated at the pixel level. The initial spheroid boundary is segmented and automated calculations of the nuclear pixel distances from the initial boundary are used to compute common invasion metrics (i.e., the change in invasion area, mean distance) for the same spheroid at a later timepoint. We also introduce the area moment of inertia as an integrative metric of cell invasion that considers the invasion area as well as the pixel distances from the initial spheroid boundary. Further, we show that principal component analysis can be used to quantify the directional influence of a stimuli to invasion (e.g., due to a chemotactic gradient or contact guidance). To demonstrate the power of the analysis for cell types with different invasive potentials and the utility of this method for a variety of biological applications, the method is used to analyze the invasiveness of five different cell types. In all, implementation of this high-throughput quantification method results in consistent and objective analysis of 3D multicellular spheroid invasion. We provide the analysis code in both MATLAB and Python languages as well as a GUI for ease of use for researchers with a range of computer programming skills and for applications in a variety of biological research areas such as wound healing and cancer metastasis.

High levels of fibrotic tumor components are associated with recurrence and intratumoral immune status in advanced colorectal cancer patients

The importance of collagen and elastin remains incompletely understood concerning tumor immunity in cancer tissues. This study explored the clinical significance of collagen and elastin deposition on tumor immunity in advanced colorectal cancer patients. The collagen and elastin contents were assessed simultaneously using elastic van Gieson (EVG) histochemical staining. Immunohistochemical staining was performed to measure the immune cell markers CD3, CD8, CD86, and CD163 in surgically resected primary tumors from 78 pT4 colorectal cancer patients. High collagen, elastin, and EVG scores are associated with aggressive characteristics and short disease-free survival. A high EVG score was identified as an independent predictor of poor disease-free survival. Furthermore, tumors with high collagen and EVG scores exhibited significantly fewer intratumoral CD3 + and CD8 + cells. Evaluating tumor fibrosis using the classical and straightforward EVG staining method could be a reliable predictor of recurrence in high-risk colorectal cancer patients with tumor immune tolerance.

Piezo1 Mediates Glycolysis-Boosted Pancreatic Ductal Adenocarcinoma Chemoresistance within a Biomimetic Three-Dimensional Matrix Stiffness

Pancreatic ductal adenocarcinoma (PDAC) is a lethal cancer with a very low 5-year survival rate, which is partially attributed to chemoresistance. Although the regulation of chemoresistance through biochemical signaling is well-documented, the influence of three-dimensional (3D) matrix stiffness is poorly understood. In this study, gelatin methacrylate (GelMA) hydrogels were reconstructed with stiffnesses spanning the range from normal to cancerous PDAC tissues, which are termed as the soft group and stiff group. The PDAC cell lines (Mia-PaCa2 and CFPAC-1) encapsulated in the stiff group displayed a chemoresistance phenotype and were prominent against gemcitabine. RNA-sequencing and bioinformatics analysis indicated that glycolysis was apparently enriched in the stiff group versus the soft group, which was also validated through assays of glucose uptake, lactate production, and the expression of GLUT2, HK2, and LDHA. A rescue assay with 2-deoxy-d-glucose and N-acetylcysteine demonstrated that glycolysis is involved in chemoresistance. Furthermore, the expression of Piezo1 and the content of Ca2+ were elevated in the stiff group. The addition of Yoda1 (Piezo1 agonist) in the soft group promoted glycolysis, whereas in the stiff group, treatment with GsMTx4 (Piezo1 inhibitor) inhibited glycolysis, which showcased that Piezo1 participated in 3D matrix stiffness-induced glycolysis. Taken together, Piezo1-mediated glycolysis was involved in PDAC chemoresistance triggered by the 3D matrix stiffness. Our study sheds light on the mechanism underlying chemoresistance in PDAC from the perspective of 3D mechanical cues.

Tumor Biomechanics-Inspired Future Medicine

Malignant tumors pose a significant global health challenge, severely threatening human health. Statistics from the World Health Organization indicate that, in 2022, there were nearly 20 million new cancer cases and 9.7 million cancer-related deaths. Therefore, it is urgently necessary to study the pathogenesis of cancer and explore effective diagnostic and treatment strategies. In recent years, research has highlighted the importance of mechanical cues in tumors, which have become a new hallmark of cancer and a key factor in regulating tumor behavior. This suggests that studying the mechanical properties of tumors may open potential new avenues for understanding the pathogenesis, diagnosis, and therapeutic intervention of cancer. This review summarizes the mechanical characteristics of tumors and the development of tumor diagnostics and treatments targeting specific mechanical factors. Finally, we propose new ideas and insights for the application of mechanomedicine in cancer diagnosis and treatment in the future.

The role of tumor microenvironment and self-organization in cancer progression: Key insights for therapeutic development

Introduction

The tumor microenvironment (TME) plays a pivotal role in cancer progression, influencing tumor initiation, growth, invasion, metastasis, and response to therapies. This study explores the dynamic interactions within the TME, particularly focusing on self-organization-a process by which tumor cells and their microenvironment reciprocally shape one another, leading to cancer progression and resistance. Understanding these interactions can reveal new prognostic markers and therapeutic targets within the TME, such as extracellular matrix (ECM) components, immune cells, and cytokine signaling pathways.

Methods

A comprehensive search method was employed to investigate the current academic literature on TME, particularly focusing on self-organization in the context of cancer progression and resistance across the PubMed, Google Scholar, and Science Direct databases.

Results

Recent studies suggest that therapies that disrupt TME self-organization could improve patient outcomes by defeating drug resistance and increasing the effectiveness of conventional therapy. Additionally, this research highlights the essential of understanding the biophysical properties of the TME, like cytoskeletal alterations, in the development of more effective malignancy therapy.

Conclusion

This review indicated that targeting the ECM and immune cells within the TME can improve therapy effectiveness. Also, by focusing on TME self-organization, we can recognize new therapeutic plans to defeat drug resistance.

Magnetic Resonance Elastography for Breast Cancer Diagnosis Through the Assessment of Tissue Biomechanical Properties

Background and Aim

Breast cancer and normal breast tissue exhibit different degrees of stiffness, indicating distinct biomechanical properties. Study results reveal that breast cancer tissue is several times stiffer than normal breast tissue. These variations can serve as indicative factors for imaging purposes. Depicting markers can significantly enhance the process of breast cancer diagnosis and treatment. This article provides a brief review of the biomechanical properties of breast cancer tissue, highlighting the role of the magnetic resonance elastography (MRE) technique in utilizing these properties for diagnosing breast cancer.

Methods

In breast MRE, low-frequency shear waves are employed to measure breast stiffness. This method not only offers a quantitative diagnosis but also generates an elastogram, determining the stiffness of each area through its colors.

Results

MRE represents a diagnostic technique with heightened sensitivity, based on depicting the viscoelasticity properties of breast tissue and describing tumors in terms of biomechanical properties. Combining tissue biomechanical properties, such as tissue stiffness, with contrast-enhanced breast Magnetic Resonance Imaging (MRI) leads to tumor diagnosis. The value of MRE in oncological imaging aims at the early detection of tumors and evaluating the prognosis of breast cancer.

Conclusion

Breast MRE can identify the reduction of interstitial pressure in tumors by detecting changes in tissue stiffness, making it an effective tool for monitoring treatment responses. This technique is safe, repeatable, and highly precise, significantly aiding in patient screening.

Spatial transcriptomics in breast cancer reveals tumour microenvironment-driven drug responses and clonal therapeutic heterogeneity

Breast cancer patients are categorized into three subtypes with distinct treatment approaches. Precision oncology has increased patient outcomes by targeting the specific molecular alterations of tumours, yet challenges remain. Treatment failure persists due to the coexistence of several malignant subpopulations with different drug sensitivities within the same tumour, a phenomenon known as intratumour heterogeneity (ITH). This heterogeneity has been extensively studied from a tumour-centric view, but recent insights underscore the role of the tumour microenvironment in treatment response. Our research utilizes spatial transcriptomics data from breast cancer patients to predict drug sensitivity. We observe diverse response patterns across tumour, interphase and microenvironment regions, unveiling a sensitivity and functional gradient from the tumour core to the periphery. Moreover, we find tumour therapeutic clusters with different drug responses associated with distinct biological functions driven by unique ligand-receptor interactions. Importantly, we identify genetically identical subclones with different responses depending on their location within the tumour ducts. This research underscores the significance of considering the distance from the tumour core and microenvironment composition when identifying suitable treatments to target ITH. Our findings provide critical insights into optimizing therapeutic strategies, highlighting the necessity of a comprehensive understanding of tumour biology for effective cancer treatment.

A highly potent bi-thiazole inhibitor of LOX rewires collagen architecture and enhances chemoresponse in triple-negative breast cancer

Lysyl oxidase (LOX) is upregulated in highly stiff aggressive tumors, correlating with metastasis, resistance, and worse survival; however, there are currently no potent, safe, and orally bioavailable small molecule LOX inhibitors to treat these aggressive desmoplastic solid tumors in clinics. Here we discovered bi-thiazole derivatives as potent LOX inhibitors by robust screening of drug-like molecules combined with cell/recombinant protein-based assays. Structure-activity relationship analysis identified a potent lead compound (LXG6403) with ∼3.5-fold specificity for LOX compared to LOXL2 while not inhibiting LOXL1 with a competitive, time- and concentration-dependent irreversible mode of inhibition. LXG6403 shows favorable pharmacokinetic properties, globally changes ECM/collagen architecture, and reduces tumor stiffness. This leads to better drug penetration, inhibits FAK signaling, and induces ROS/DNA damage, G1 arrest, and apoptosis in chemoresistant triple-negative breast cancer (TNBC) cell lines, PDX organoids, and in vivo. Overall, our potent and tolerable bi-thiazole LOX inhibitor enhances chemoresponse in TNBC, the deadliest breast cancer subtype.

Ovarian cancer cells exhibit diverse migration strategies on stiff collagenous substrata

In homoeostasis, the shape and sessility of untransformed epithelial cells are intricately linked together. Variations of this relationship in migrating cancer cells as they encounter different microenvironments are as yet ill understood. Here, we explore the interdependency of such traits in two morphologically distinct invasive ovarian cancer cell lines (OVCAR-3 and SK-OV-3) under mechanically variant contexts. We first established a metric toolkit that assessed traits associated with cell motion and shape, and rigorously measured their dynamical variation across trajectories of migration using a Shannon entropic distribution. Two stiffness conditions on polymerized collagen I with Young's moduli of 0.5 kPa (soft) and 20 kPa (stiff) were chosen. Both the epithelioid OVCAR-3 and mesenchymal SK-OV-3 cells on soft substrata exhibited slow and undirected migration. On stiff substrata, SK-OV-3 showed faster persistent directed motion. Surprisingly, OVCAR-3 cells on stiffer substrata moved even faster than SK-OV-3 cells but showed a distinct angular motion. The polarity of SK-OV-3 cells on stiff substrata was well correlated with their movement, whereas, for OVCAR-3, we observed an unusual "slip" behavior, wherein the axes of cell shape and movement were poorly correlated. Whereas SK-OV-3 and OVCAR-3 showed greater mean deformation on stiffer substrata, the latter was anticorrelated with variation in angular motion or the mean deviation between shape and motility axis for SK-OV-3 but poorly correlated for OVCAR-3. Moreover, on softer substrata OVCAR-3 and SK-OV-3 were relatively rigid but showed greater shape variation (with OVCAR-3 showing a higher fold change) on stiffer substrata. Our findings suggest that greater deformability on stiffer milieu allow epithelioid cells to overcome constraints on the congruence in axis of shape and motion seen for mesenchymal cells and display distinct motile behaviors across this phenotypic spectrum.

Tumor microenvironment and cancer metastasis: molecular mechanisms and therapeutic implications

The tumor microenvironment (TME) plays a crucial role in cancer development and metastasis. This review summarizes the current research on how the TME promotes metastasis through molecular pathways, focusing on key components, such as cancer-associated fibroblasts, immune cells, endothelial cells, cytokines, and the extracellular matrix. Significant findings have highlighted that alterations in cellular communication within the TME enable tumor cells to evade immune surveillance, survive, and invade other tissues. This review highlights the roles of TGF-β and VEGF signaling in promoting angiogenesis and extracellular matrix remodeling, which facilitate metastasis. Additionally, we explored how metabolic reprogramming of tumor and stromal cells, influenced by nutrient availability in the TME, drives cancer progression. This study also evaluated the therapeutic strategies targeting these interactions to disrupt metastasis. By providing a multidisciplinary perspective, this study suggests that understanding the molecular basis of the TME can lead to more effective cancer therapies and identify potential avenues for future research. Future research on the TME should prioritize unraveling the molecular and cellular interactions within this complex environment, which could lead to novel therapeutic strategies and personalized cancer treatments. Moreover, advancements in technologies such as single-cell analysis, spatial transcriptomics, and epigenetic profiling offer promising avenues for identifying new therapeutic targets and improving the efficacy of immunotherapies, particularly in the context of metastasis.

Mechanisms of assembly and remodelling of the extracellular matrix

The extracellular matrix (ECM) is the complex meshwork of proteins and glycans that forms the scaffold that surrounds and supports cells. It exerts key roles in all aspects of metazoan physiology, from conferring physical and mechanical properties on tissues and organs to modulating cellular processes such as proliferation, differentiation and migration. Understanding the mechanisms that orchestrate the assembly of the ECM scaffold is thus crucial to understand ECM functions in health and disease. This Review discusses novel insights into the compositional diversity of matrisome components and the mechanisms that lead to tissue-specific assemblies and architectures tailored to support specific functions. The Review then highlights recently discovered mechanisms, including post-translational modifications and metabolic pathways such as amino acid availability and the circadian clock, that modulate ECM secretion, assembly and remodelling in homeostasis and human diseases. Last, the Review explores the potential of 'matritherapies', that is, strategies to normalize ECM composition and architecture to achieve a therapeutic benefit.