Piezo1 Mechano-Activation Is Augmented by Resveratrol and Differs between Colorectal Cancer Cells of Primary and Metastatic Origin

Impact of stroma remodeling on forces experienced by cancer cells and stromal cells within a pancreatic tumor tissue

Remodeling (re-engineering) of a tumor's stroma has been shown to improve the efficacy of anti-tumor therapies, without destroying the stroma. Even though it still remains unclear which stromal component/-s and what characteristics hinder the reach of nanoparticles deep into cancer cells, we hypothesis that mechanisms behind stroma's resistance to the penetration of nanoparticles rely heavily on extrinsic mechanical forces on stromal cells and cancer cells. Our hypothesis has been formulated on the basis of our previous study which has shown that changes in extracellular matrix (ECM) stiffness with tumor growth influence stresses exerted on fibroblasts and cancer cells, and that malignant cancer cells generate higher stresses on their stroma. This study attempts to establish a distinct identification of the components' remodeling on the distribution and magnitude of stress within a tumor tissue which ultimately will impact the resistance of stroma to treatment. In this study, our objective is to construct a three-dimensional in silico model of a pancreas tumor tissue consisting of cancer cells, stromal cells, and ECM to determine how stromal remodeling alters the stresses distribution and magnitude within the pancreas tumor tissue. Our results show that changes in mechanical properties of ECM significantly alter the magnitude and distribution of stresses within the pancreas tumor tissue. Our results revealed that these stresses are more sensitive to ECM properties as we see the stresses reaching to a maximum of 22,000 Pa for softer ECM with Young's modulus of 250 Pa. The stress distribution and magnitude within the pancreas tumor tissue does not show high sensitivity to the changes in mechanical properties of stromal cells surrounding stiffer cancer cells (PANC-1 with Young's modulus of 2400 Pa). However, softer cancer cells (MIA-PaCa-2 with (Young's modulus of 500 Pa) increase the stresses experienced by stiffer stromal cells and for stiffer ECM. By providing a unique platform to dissect and quantify the impact of individual stromal components on the stress distribution within a tumor tissue, this study serves as an important first step in understanding of which stromal components are vital for an efficient remodeling. This knowledge will be leveraged to overcome a tumor's resistance against the penetration of nanoparticles on a per-patient basis.

Superhydrophobic Array Devices for the Enhanced Formation of 3D Cancer Models

During the metastatic cascade, cancer cells travel through the bloodstream as circulating tumor cells (CTCs) to a secondary site. Clustered CTCs have greater shear stress and treatment resistance, yet their biology remains poorly understood. We therefore engineered a tunable superhydrophobic array device (SHArD). The SHArD-C was applied to culture a clinically relevant model of CTC clusters. Using our device, we cultured a model of cancer cell aggregates of various sizes with immortalized cancer cell lines. These exhibited higher E-cadherin expression and are significantly more capable of surviving high fluid shear stress-related forces compared to single cells and model clusters grown using the control method, helping to explain why clustering may provide a metastatic advantage. Additionally, the SHArD-S, when compared with the AggreWell 800 method, provides a more consistent spheroid-forming device culturing reproducible sizes of spheroids for multiple cancer cell lines. Overall, we designed, fabricated, and validated an easily tunable engineered device which grows physiologically relevant three-dimensional (3D) cancer models containing tens to thousands of cells.

Role of STIM1 in stretch-induced signaling in human airway smooth muscle

Alteration in the normal mechanical forces of breathing can contribute to changes in contractility and remodeling characteristic of airway diseases, but the mechanisms that mediate these effects in airway cells are still under investigation. Airway smooth muscle (ASM) cells contribute to both contractility and extracellular matrix (ECM) remodeling. In this study, we explored ASM mechanisms activated by mechanical stretch, focusing on mechanosensitive piezo channels and the key Ca2+ regulatory protein stromal interaction molecule 1 (STIM1). Expression of Ca2+ regulatory proteins, including STIM1, Orai1, and caveolin-1, mechanosensitive ion channels Piezo-1 and Piezo-2, and NLRP3 inflammasomes were upregulated by 10% static stretch superimposed on 5% cyclic stretch. These effects were blunted by STIM1 siRNA. Histamine-induced [Ca2+]i responses and inflammasome activation were similarly blunted by STIM1 knockdown. These data show that the effects of mechanical stretch in human ASM cells are mediated through STIM1, which activates multiple pathways, including Piezo channels and the inflammasome, leading to potential downstream changes in contractility and ECM remodeling.NEW & NOTEWORTHY Mechanical forces on the airway can contribute to altered contractility and remodeling in airway diseases, but the mechanisms are not clearly understood. Using human airway smooth muscle cells exposed to cyclic forces with static stretch to mimic breathing and static pressure, we found that the effects of stretch are mediated through STIM1, resulting in the activation of multiple pathways, including Piezo channels and the inflammasome, with potential downstream influences on contractility and remodeling.

Pleiotropic physiological functions of Piezo1 in human body and its effect on malignant behavior of tumors

Mechanosensitive ion channel protein 1 (Piezo1) is a large homotrimeric membrane protein. Piezo1 has various effects and plays an important and irreplaceable role in the maintenance of human life activities and homeostasis of the internal environment. In addition, recent studies have shown that Piezo1 plays a vital role in tumorigenesis, progression, malignancy and clinical prognosis. Piezo1 is involved in regulating the malignant behaviors of a variety of tumors, including cellular metabolic reprogramming, unlimited proliferation, inhibition of apoptosis, maintenance of stemness, angiogenesis, invasion and metastasis. Moreover, Piezo1 regulates tumor progression by affecting the recruitment, activation, and differentiation of multiple immune cells. Therefore, Piezo1 has excellent potential as an anti-tumor target. The article reviews the diverse physiological functions of Piezo1 in the human body and its major cellular pathways during disease development, and describes in detail the specific mechanisms by which Piezo1 affects the malignant behavior of tumors and its recent progress as a new target for tumor therapy, providing new perspectives for exploring more potential effects on physiological functions and its application in tumor therapy.

Spatial distribution of tumor-associated macrophages in an orthotopic prostate cancer mouse model

Mounting evidence suggests that the immune landscape within prostate tumors influences progression, metastasis, treatment response, and patient outcomes. In this study, we investigated the spatial density of innate immune cell populations within NOD.SCID orthotopic prostate cancer xenografts following microinjection of human DU145 prostate cancer cells. Our laboratory has previously developed nanoscale liposomes that attach to leukocytes via conjugated E-selectin (ES) and kill cancer cells via TNF-related apoptosis inducing ligand (TRAIL). Immunohistochemistry (IHC) staining was performed on tumor samples to identify and quantify leukocyte infiltration for different periods of tumor growth and E-selectin/TRAIL (EST) liposome treatments. We examined the spatial-temporal dynamics of three different immune cell types infiltrating tumors using QuPath image analysis software. IHC staining revealed that F4/80+ tumor-associated macrophages (TAMs) were the most abundant immune cells in all groups, irrespective of time or treatment. The density of TAMs decreased over the course of tumor growth and decreased in response to EST liposome treatments. Intratumoral versus marginal analysis showed a greater presence of TAMs in the marginal regions at 3 weeks of tumor growth which became more evenly distributed over time and in tumors treated with EST liposomes. TUNEL staining indicated that EST liposomes significantly increased cell apoptosis in treated tumors. Additionally, confocal microscopy identified liposome-coated TAMs in both the core and periphery of tumors, highlighting the ability of liposomes to infiltrate tumors by "piggybacking" on macrophages. The results of this study indicate that TAMs represent the majority of innate immune cells within NOD.SCID orthotopic prostate tumors, and spatial density varies widely as a function of tumor size, duration of tumor growth, and treatment of EST liposomes.

Modeling Physical Forces Experienced by Cancer and Stromal Cells Within Different Organ-Specific Tumor Tissue

Mechanical force exerted on cancer cells by their microenvironment have been reported to drive cells toward invasive phenotypes by altering cells' motility, proliferation, and apoptosis. These mechanical forces include compressive, tensile, hydrostatic, and shear forces. The importance of forces is then hypothesized to be an alteration of cancer cells' and their microenvironment's biophysical properties as the indicator of a tumor's malignancy state. Our objective is to investigate and quantify the correlation between a tumor's malignancy state and forces experienced by the cancer cells and components of the microenvironment. In this study, we have developed a multicomponent, three-dimensional model of tumor tissue consisting of a cancer cell surrounded by fibroblasts and extracellular matrix (ECM). Our results on three different organs including breast, kidney, and pancreas show that: A) the stresses within tumor tissue are impacted by the organ specific ECM's biophysical properties, B) more invasive cancer cells experience higher stresses, C) in pancreas which has a softer ECM (Young modulus of 1.0 kPa) and stiffer cancer cells (Young modulus of 2.4 kPa and 1.7 kPa) than breast and kidney, cancer cells experienced significantly higher stresses, D) cancer cells in contact with ECM experienced higher stresses compared to cells surrounded by fibroblasts but the area of tumor stroma experiencing high stresses has a maximum length of 40 μm when the cancer cell is surrounded by fibroblasts and 12 μm for when the cancer cell is in vicinity of ECM. This study serves as an important first step in understanding of how the stresses experienced by cancer cells, fibroblasts, and ECM are associated with malignancy states of cancer cells in different organs. The quantification of forces exerted on cancer cells by different organ-specific ECM and at different stages of malignancy will help, first to develop theranostic strategies, second to predict accurately which tumors will become highly malignant, and third to establish accurate criteria controlling the progression of cancer cells malignancy. Furthermore, our in silico model of tumor tissue can yield critical, useful information for guiding ex vivo or in vitro experiments, narrowing down variables to be investigated, understanding what factors could be impacting cancer treatments or even biomarkers to be looking for.

TRAIL-conjugated liposomes that bind natural killer cells to induce colorectal cancer cell apoptosis

Natural killer (NK) cell functionality is a strong indicator of favorable prognosis in cancer patients, making NK cells an appealing therapeutic target to prevent lymph node dissemination. We engineered liposomes that are conjugated with anti-CD335 antibodies for NK cell targeting, and the apoptotic ligand TRAIL to kill cancer cells. Liposomes were made using a thin film hydration method followed by extrusion to approximately 100 nm in diameter and conjugation of proteins via thiol-maleimide click chemistry. TRAIL/anti-CD335 liposomes successfully bound to isolated NK cells. Once piggybacked to the surface of NK cells, these "Super Natural Killer Cells" were able to more effectively kill oxaliplatin-resistant SW620 cells and metastatic COLO205 colorectal cancer cells via TRAIL-mediated apoptosis compared to NK cells alone. Importantly, Super NK cells were more effective under physiological levels of fluid shear stress found in the lymphatics. Liposome biodistribution after intravenous administration confirmed the sustained presence of liposomes within the spleen and tumor draining mesenteric lymph nodes for at least 4 days. These results demonstrate the enhanced apoptotic effects of NK cells armored with liposomal TRAIL against clinically relevant colorectal cancer cells, providing the groundwork for in vivo treatment studies in mouse models of colorectal cancer metastasis.

Computational identification of potential inhibitors targeting cdk1 in colorectal cancer

Introduction: Despite improved treatment options, colorectal cancer (CRC) remains a huge public health concern with a significant impact on affected individuals. Cell cycle dysregulation and overexpression of certain regulators and checkpoint activators are important recurring events in the progression of cancer. Cyclin-dependent kinase 1 (CDK1), a key regulator of the cell cycle component central to the uncontrolled proliferation of malignant cells, has been reportedly implicated in CRC. This study aimed to identify CDK1 inhibitors with potential for clinical drug research in CRC. Methods: Ten thousand (10,000) naturally occurring compounds were evaluated for their inhibitory efficacies against CDK1 through molecular docking studies. The stability of the lead compounds in complex with CDK1 was evaluated using molecular dynamics simulation for one thousand (1,000) nanoseconds. The top-scoring candidates' ADME characteristics and drug-likeness were profiled using SwissADME. Results: Four hit compounds, namely, spiraeoside, robinetin, 6-hydroxyluteolin, and quercetagetin were identified from molecular docking analysis to possess the least binding scores. Molecular dynamics simulation revealed that robinetin and 6-hydroxyluteolin complexes were stable within the binding pocket of the CDK1 protein. Discussion: The findings from this study provide insight into novel candidates with specific inhibitory CDK1 activities that can be further investigated through animal testing, clinical trials, and drug development research for CRC treatment.

Dual Affinity Nanoparticles for the Transport of Therapeutics from Carrier Cells to Target Cells under Physiological Flow Conditions

In this study, a novel two-stage nanoparticle delivery platform was developed based on the dual functionalization of a liposome with moieties that have fundamentally different strengths of adhesion and binding kinetics. The essential concept of this system is that the nanoparticles are designed to loosely bind to the carrier cell until they come into contact with the target cell, to which they bind with greater strength. This allows the nanoparticle to be transferred from one cell to another, circulating for longer periods of time in the blood and delivering the therapeutic agent to the target circulating tumor cell. Liposomes were prepared using the lipid cake and extrusion technique, then functionalized with E-selectin (ES), anti-cell surface vimentin antibody fragments, and TRAIL via click chemistry. The binding of dual affinity (DA) liposomes was confirmed with the neutrophil-like cell line PLB985, the colorectal cancer cell line HCT116, and healthy granulocytes isolated from peripheral whole blood under physiologically relevant fluid shear stress (FSS) in a cone-and-plate viscometer. Transfer of the DA liposomes from PLB985 to HCT116 cells under FSS was greater compared to all of the control liposome formulations. Additionally, DA liposomes demonstrated enhanced apoptotic effects on HCT116 cells in whole blood under FSS, surpassing the efficacy of the ES/TRAIL liposomes previously developed by the King Lab.

Integration of Patient-Derived Organoids and Organ-on-Chip Systems: Investigating Colorectal Cancer Invasion within the Mechanical and GABAergic Tumor Microenvironment

Three-dimensional (3D) in vitro models are essential in cancer research, but they often neglect physical forces. In our study, we combined patient-derived tumor organoids with a microfluidic organ-on-chip system to investigate colorectal cancer (CRC) invasion in the tumor microenvironment (TME). This allowed us to create patient-specific tumor models and assess the impact of physical forces on cancer biology. Our findings showed that the organoid-on-chip models more closely resembled patient tumors at the transcriptional level, surpassing organoids alone. Using 'omics' methods and live-cell imaging, we observed heightened responsiveness of KRAS mutant tumors to TME mechanical forces. These tumors also utilized the γ-aminobutyric acid (GABA) neurotransmitter as an energy source, increasing their invasiveness. This bioengineered model holds promise for advancing our understanding of cancer progression and improving CRC treatments.

Mechanosensitive ion channels in apoptosis and ferroptosis: focusing on the role of Piezo1

Mechanosensitive ion channels sense mechanical stimuli applied directly to the cellular membranes or indirectly through their tethered components, provoking cellular mechanoresponses. Among others, Piezo1 mechanosensitive ion channel is a relatively novel Ca2+-permeable channel that is primarily present in non-sensory tissues. Recent studies have demonstrated that Piezo1 plays an important role in Ca2+-dependent cell death, including apoptosis and ferroptosis, in the presence of mechanical stimuli. It has also been proven that cancer cells are sensitive to mechanical stresses due to higher expression levels of Piezo1 compared to normal cells. In this review, we discuss Piezo1-mediated cell death mechanisms and therapeutic strategies to inhibit or induce cell death by modulating the activity of Piezo1 with pharmacological drugs or mechanical perturbations induced by stretch and ultrasound. [BMB Reports 2023; 56(3): 145-152].