Piezo-type mechanosensitive ion channel component 1 (Piezo1) in human cancer

Piezo1, the new actor in cell volume regulation

All animal cells control their volume through a complex set of mechanisms, both to counteract osmotic perturbations of the environment and to enable numerous vital biological processes, such as proliferation, apoptosis, and migration. The ability of cells to adjust their volume depends on the activity of ion channels and transporters which, by moving K+, Na+, and Cl- ions across the plasma membrane, generate the osmotic gradient that drives water in and out of the cell. In 2010, Patapoutian's group identified a small family of evolutionarily conserved, Ca2+-permeable mechanosensitive channels, Piezo1 and Piezo2, as essential components of the mechanically activated current that mediates mechanotransduction in vertebrates. Piezo1 is expressed in several tissues and its opening is promoted by a wide range of mechanical stimuli, including membrane stretch/deformation and osmotic stress. Piezo1-mediated Ca2+ influx is used by the cell to convert mechanical forces into cytosolic Ca2+ signals that control diverse cellular functions such as migration and cell death, both dependent on changes in cell volume and shape. The crucial role of Piezo1 in the regulation of cell volume was first demonstrated in erythrocytes, which need to reduce their volume to pass through narrow capillaries. In HEK293 cells, increased expression of Piezo1 was found to enhance the regulatory volume decrease (RVD), the process whereby the cell re-establishes its original volume after osmotic shock-induced swelling, and it does so through Ca2+-dependent modulation of the volume-regulated anion channels. More recently we reported that Piezo1 controls the RVD in glioblastoma cells via the modulation of Ca2+-activated K+ channels. To date, however, the mechanisms through which this mechanosensitive channel controls cell volume and maintains its homeostasis have been poorly investigated and are still far from being understood. The present review aims to provide a broad overview of the literature discussing the recent advances on this topic.

Targeting Nrf2 signaling pathways in the role of bladder cancer: From signal network to targeted therapy

Bladder cancer (BC) is the most common malignancy of the urinary system and often recurs after tumor removal and/or is resistant to chemotherapy. In cancer cells, the activity of the signaling pathway changes significantly, affecting a wide range of cell activities from growth and proliferation to apoptosis, invasion and metastasis. Nrf2 is a transcription factor that plays an important role in cellular defense responses to a variety of cellular stresses. There is increasing evidence that Nrf2 acts as a tumor driver and that it is involved in the maintenance of malignant cell phenotypes. Abnormal expression of Nrf2 has been found to be common in a variety of tumors, including bladder cancer. Over-activation of Nrf2 can lead to DNA damage and the development of bladder cancer, and is also associated with various pathological phenomena of bladder cancer, such as metastasis, angiogenesis, and reduced toxicity and efficacy of therapeutic anticancer drugs to provide cell protection for cancer cells. However, the above process can be effectively inhibited or reversed by inhibiting Nrf2. Therefore, Nrf2 signaling may be a potential targeting pathway for bladder cancer. In this review, we will characterize this signaling pathway and summarize the effects of Nrf2 and crosstalk with other signaling pathways on bladder cancer progression. The focus will be on the impact of Nrf2 activation on bladder cancer progression and current therapeutic strategies aimed at blocking the effects of Nrf2. To better determine how to promote new chemotherapy agents, develop new therapeutic agents, and potential therapeutic targets.

Piezo channels in the intestinal tract

The intestine is the largest mechanosensitive organ in the human body whose epithelial cells, smooth muscle cells, neurons and enteroendocrine cells must sense and respond to various mechanical stimuli such as motility, distension, stretch and shear to regulate physiological processes including digestion, absorption, secretion, motility and immunity. Piezo channels are a newly discovered class of mechanosensitive ion channels consisting of two subtypes, Piezo1 and Piezo2. Piezo channels are widely expressed in the intestine and are involved in physiological and pathological processes. The present review summarizes the current research progress on the expression, function and regulation of Piezo channels in the intestine, with the aim of providing a reference for the future development of therapeutic strategies targeting Piezo channels.

The post-chemotherapy changes of tumor physical microenvironment: Targeting extracellular matrix to address chemoresistance

The tumor physical microenvironment (TPME) contributes to cancer chemoresistance in both mechanical and mechanobiological approaches. Along with chemotherapy, the tumor microenvironment undergoes dramatic changes, most of which can regulate TPME through extracellular matrix (ECM) remodeling and related signaling pathways. However, there is still no discussion about the post-chemotherapy TPME changes mediated by ECM remodeling, and consequent impact on chemoresistance. Herein, we summarize the TPME alterations induced by chemotherapy and corresponding influence on chemotherapy response of cancer cells in context of ECM. The response of cancer cell to chemotherapy, imposed by post-chemotherapy ECM, are discussed in both mechanical (ECM physical features) and mechanobiological (ECM-responsive signaling pathways) manner. In the end, we present ECM remodeling and related signaling pathways as two promising clinic strategies to relieve or overcome chemoresistance induced by TPME change, and summarize the corresponding therapeutic agents currently being tested in clinical trials.

Mechanosensitive Cation Channel Piezo1 Is Involved in Renal Fibrosis Induction

Renal fibrosis, the result of different pathological processes, impairs kidney function and architecture, and usually leads to renal failure development. Piezo1 is a mechanosensitive cation channel highly expressed in kidneys. Activation of Piezo1 by mechanical stimuli increases cations influx into the cell with slight preference of calcium ions. Two different models of Piezo1 activation are considered: force through lipid and force through filament. Expression of Piezo1 on mRNA and protein levels was confirmed within the kidney. Their capacity is increased in the fibrotic kidney. The pharmacological tools for Piezo1 research comprise selective activators of the channels (Yoda1 and Jedi1/2) as well as non-selective inhibitors (spider peptide toxin) GsMTx4. Piezo1 is hypothesized to be the upstream element responsible for the activation of integrin. This pathway (calcium/calpain2/integrin beta1) is suggested to participate in profibrotic response induced by mechanical stimuli. Administration of the Piezo1 unspecific inhibitor or activators to unilateral ureter obstruction (UUO) mice or animals with folic acid-induced fibrosis modulates extracellular matrix deposition and influences kidney function. All in all, according to the recent data Piezo1 plays an important role in kidney fibrosis development. This channel has been selected as the target for pharmacotherapy of renal fibrosis.

PIEZO2 expression is an independent biomarker prognostic for gastric cancer and represents a potential therapeutic target

Gastric cancer (GC) is one of the most prevalent malignant tumors of the gastrointestinal system in the globe. The effect of PIEZO2 on the immune function and pathological features of gastric cancer remains to be explored. The Online database of cancer genes and GSE54129 have been used to analyze the clinical characteristics of PIEZO2 expression. We looked at the relationship between PIEZO2 and the immune systems of GC patients. The TIDE algorithm was used to explore the value of PIEZO2 in immunotherapy. Investigated the enrichment of PIEZO2 gene ontology and associated signal pathways using Online gene databases. The results show that overexpression of PIEZO2 was identified as an independent risk factor for patients with GC who had poor overall survival. Individuals may have a better prognosis if they had poorly differentiated GC and increased PIEZO2 expression (P < 0.05). We demonstrated a strong correlation between PIEZO2 and immune cells. The majority of immune checkpoint and immunological-related genes were associated with PIEZO2 expression. And PIEZO2 might be used as an immunotherapy target. Finally, the differential PIEZO2 genes in GC were mostly implicated in the processes of inflammation, immunological response, and tumor metastasis, according to functional analysis. PIEZO2 has a negative correlation with cell stemness and mutation levels in patients with GC and a positive correlation with immune cell infiltration and gene expression in the tumor microenvironment. These findings point to PIEZO2 as a potential new immunotherapy target of GC.

Extracellular Matrix Cues Regulate Mechanosensing and Mechanotransduction of Cancer Cells

Extracellular biophysical properties have particular implications for a wide spectrum of cellular behaviors and functions, including growth, motility, differentiation, apoptosis, gene expression, cell-matrix and cell-cell adhesion, and signal transduction including mechanotransduction. Cells not only react to unambiguously mechanical cues from the extracellular matrix (ECM), but can occasionally manipulate the mechanical features of the matrix in parallel with biological characteristics, thus interfering with downstream matrix-based cues in both physiological and pathological processes. Bidirectional interactions between cells and (bio)materials in vitro can alter cell phenotype and mechanotransduction, as well as ECM structure, intentionally or unintentionally. Interactions between cell and matrix mechanics in vivo are of particular importance in a variety of diseases, including primarily cancer. Stiffness values between normal and cancerous tissue can range between 500 Pa (soft) and 48 kPa (stiff), respectively. Even the shear flow can increase from 0.1-1 dyn/cm2 (normal tissue) to 1-10 dyn/cm2 (cancerous tissue). There are currently many new areas of activity in tumor research on various biological length scales, which are highlighted in this review. Moreover, the complexity of interactions between ECM and cancer cells is reduced to common features of different tumors and the characteristics are highlighted to identify the main pathways of interaction. This all contributes to the standardization of mechanotransduction models and approaches, which, ultimately, increases the understanding of the complex interaction. Finally, both the in vitro and in vivo effects of this mechanics-biology pairing have key insights and implications for clinical practice in tumor treatment and, consequently, clinical translation.

Autophagy modulation changes mechano-chemical sensitivity of T24 bladder cancer cells

Bladder cancer cells possess unique adaptive capabilities: shaped by their environment, cells face a complex chemical mixture of metabolites and xenobiotics accompanied by physiological mechanical cues. These responses might translate into resistance to chemotherapeutical regimens and can largely rely on autophagy. Considering molecules capable of rewiring tumor plasticity, compounds of natural origin promise to offer valuable options. Fungal derived metabolites, such as bafilomycin and wortmannin are widely acknowledged as autophagy inhibitors. Here, their potential to tune bladder cancer cells´ adaptability to chemical and physical stimuli was assessed. Additionally, dietary occurring mycotoxins were also investigated, namely deoxynivalenol (DON, 0.1-10 µM) and fusaric acid (FA, 0.1-1 mM). Endowing a Janus' face behavior, DON and FA are on the one side described as toxins with detrimental health effects. Concomitantly, they are also explored experimentally for selective pharmacological applications including anticancer activities. In non-cytotoxic concentrations, bafilomycin (BAFI, 1-10 nM) and wortmannin (WORT, 1 µM) modified cell morphology and reduced cancer cell migration. Application of shear stress and inhibition of mechano-gated PIEZO channels reduced cellular sensitivity to BAFI treatment (1 nM). Similarly, for FA (0.5 mM) PIEZO1 expression and inhibition largely aligned with the modulatory potential on cancer cells motility. Additionally, this study highlighted that the activity profile of compounds with similar cytotoxic potential (e.g. co-incubation DON with BAFI or FA with WORT) can diverge substantially in the regulation of cell mechanotransduction. Considering the interdependence between tumor progression and response to mechanical cues, these data promise to provide a novel viewpoint for the study of chemoresistance and associated pathways.

PIEZO1 is essential for the survival and proliferation of acute myeloid leukemia cells

INTRODUCTION

Leukemogenesis is a complex process that interconnects tumoral cells with their microenvironment, but the effect of mechanosensing in acute myeloid leukemia (AML) blasts is poorly known. PIEZO1 perceives and transmits the constraints of the environment to human cells by acting as a non-selective calcium channel, but very little is known about its role in leukemogenesis.

RESULTS

For the first time, we show that PIEZO1 is preferentially expressed in healthy hematopoietic stem and progenitor cells in human hematopoiesis, and globally overexpressed in AML cells. In AML subtypes, PIEZO1 expression associates with favorable outcomes as better overall (OS) and disease-free survival (DFS). If PIEZO1 is expressed and functional in THP1 leukemic myeloid cell line, its chemical activation doesn't impact the proliferation, differentiation, nor survival of cells. However, the downregulation of PIEZO1 expression dramatically reduces the proliferation and the survival of THP1 cells. We show that PIEZO1 knock-down blocks the cell cycle in G0/G1 phases of AML cells, impairs the DNA damage response pathways, and critically increases cell death by triggering extrinsic apoptosis pathways.

CONCLUSIONS

Altogether, our results reveal a new role for PIEZO1 mechanosensing in the survival and proliferation of leukemic blasts, which could pave the way for new therapeutic strategies to target AML cells.

Bibliometric analysis of the global research status and trends of mechanotransduction in cancer

BACKGROUND

The development of cancer is thought to involve the dynamic crosstalk between the tumor cells and the microenvironment they inhabit. Such crosstalk is thought to involve mechanotransduction, a process whereby the cells sense mechanical cues such as stiffness, and translate these into biochemical signals, which have an impact on the subsequent cellular activities. Bibliometric analysis is a statistical method that involves investigating different aspects (including authors' names and affiliations, article keywords, journals and citations) of large volumes of literature. Despite an increase in mechanotransduction-related research in recent years, there are currently no bibliometric studies that describe the global status and trends of mechanotransduction-related research in the cancer field.

AIM

To investigate the global research status and trends of mechanotransduction in cancer from a bibliometric viewpoint.

METHODS

Literature on mechanotransduction in cancer published from January 1, 1900 to December 31, 2022 was retrieved from the Web of Science Core Collection. Excel and GraphPad software carried out the statistical analysis of the relevant author, journal, organization, and country information. The co-authorship, keyword co-occurrence, and keyword burst analysis were visualized with VOSviewer and CiteSpace.

RESULTS

Of 597 publications from 745 institutions in 45 countries were published in 268 journals with 35510 citation times. With 270 articles, the United States is a well-established global leader in this field, and the University of California system, the most productive (n = 36) and influential institution (n = 4705 citations), is the most highly active in collaborating with other organizations. Cancers was the most frequent publisher with the highest H-index. The most productive researcher was Valerie M. Weaver, with 10 publications. The combined analysis of concurrent and burst keywords revealed that the future research hotspots of mechanotransduction in cancer were related to the plasma membrane, autophagy, piezo1/2, heterogeneity, cancer diagnosis, and post-transcriptional modifications.

CONCLUSION

Mechanotransduction-related cancer research remains a hot topic. The United States is in the leading position of global research on mechano-oncology after almost 30 years of investigations. Research group cooperations exist but remain largely domestic, lacking cross-national communications. The next big topic in this field is to explore how the plasma membrane and its localized mechanosensor can transduce mechanical force through post-transcriptional modifications and thereby participate in cellular activity regulations and cancer development.

The role of non-canonical Hippo pathway in regulating immune homeostasis

The Hippo pathway is a crucial signaling pathway that is highly conserved throughout evolution for the regulation of organ size and maintenance of tissue homeostasis. Initial studies have primarily focused on the canonical Hippo pathway, which governs organ development, tissue regeneration, and tumorigenesis. In recent years, extensive research has revealed that the non-canonical Hippo pathway, centered around Mst1/2 as its core molecule, plays a pivotal role in immune response and function by synergistically interacting with other signal transduction pathways. Consequently, the non-canonical Hippo pathway assumes significant importance in maintaining immune system homeostasis. This review concentrates on the research progress of the non-canonical Hippo pathway in regulating innate immune cell anti-infection responses, maintaining redox homeostasis, responding to microenvironmental stiffness, and T-cell differentiation.

The cation-leaky hereditary stomatocytosis syndromes: A tale of six proteins

This review concerns a series of dominantly inherited haemolytic anaemias in which the membrane of the erythrocyte 'leaks' the univalent cations, compromising the osmotic stability of the cell. The majority of the conditions are explained by mutations in one of six genes, coding for multispanning membrane proteins of different structure and function. These are: RhAG, coding for an ammonium carrier; SLC4A1, coding for the band 3 anion exchanger; PIEZO1, coding for a mechanosensitive cation channel; GLUT1, coding for a glucose transporter; KCNN4, coding for an internal-calcium-activated potassium channel; and ABCB6, coding for a porphyrin transporter. This review describes the five clinical syndromes associated with genetic defects in these genes and their variable genotype/phenotype relationships.

Joining forces: crosstalk between mechanosensitive PIEZO1 ion channels and integrin-mediated focal adhesions

Both integrin-mediated focal adhesions (FAs) and mechanosensitive ion channels such as PIEZO1 are critical in mechanotransduction processes that influence cell differentiation, development, and cancer. Ample evidence now exists for regulatory crosstalk between FAs and PIEZO1 channels with the molecular mechanisms underlying this process remaining unclear. However, an emerging picture is developing based on spatial crosstalk between FAs and PIEZO1 revealing a synergistic model involving the cytoskeleton, extracellular matrix (ECM) and calcium-dependent signaling. Already cell type, cell contractility, integrin subtypes and ECM composition have been shown to regulate this crosstalk, implying a highly fine-tuned relationship between these two major mechanosensing systems. In this review, we summarize the latest advances in this area, highlight the physiological implications of this crosstalk and identify gaps in our knowledge that will improve our understanding of cellular mechanosensing.

Piezo1 in skin wound healing and related diseases: Mechanotransduction and therapeutic implications

Skin wound healing is a multifaceted and intricate process involving inflammation, tissue proliferation, and scar formation, all of which are accompanied by the continuous application of mechanical forces. Mechanotransduction is the mechanism by which the skin receives and reacts to physical signals from the internal and external environment, converting them into intracellular biochemical signals. This intricate process relies on specialized proteins known as mechanotransducers, with Piezo1 being a critical mechanosensitive ion channel that plays a central role in this process. This article provides an overview of the structural characteristics of Piezo1 and summarizes its effects on corresponding cells or tissues at different stages of skin trauma, including how it regulates skin sensation and skin-related diseases. The aim is to reveal the potential diagnostic and therapeutic value of Piezo1 in skin trauma and skin-related diseases. Piezo1 has been reported to be a vital mediator of mechanosensation and transduction in various organs and tissues. Given its high expression in the skin, Piezo1, as a significant cell membrane ion channel, is essential in activating intracellular signaling cascades that trigger several cellular physiological functions, including cell migration and muscle contraction. These functions contribute to the regulation and improvement of wound healing.

A review of the pathophysiology and the role of ion channels on bronchial asthma

Asthma is one of the main non-communicable chronic diseases and affects a huge portion of the population. It is a multifactorial disease, classified into several phenotypes, being the allergic the most frequent. The pathophysiological mechanism of asthma involves a Th2-type immune response, with high concentrations of allergen-specific immunoglobulin E, eosinophilia, hyperreactivity and airway remodeling. These mechanisms are orchestrated by intracellular signaling from effector cells, such as lymphocytes and eosinophils. Ion channels play a fundamental role in maintaining the inflammatory response on asthma. In particular, transient receptor potential (TRP), stock-operated Ca2+ channels (SOCs), Ca2+-activated K+ channels (IKCa and BKCa), calcium-activated chloride channel (TMEM16A), cystic fibrosis transmembrane conductance regulator (CFTR), piezo-type mechanosensitive ion channel component 1 (PIEZO1) and purinergic P2X receptor (P2X). The recognition of the participation of these channels in the pathological process of asthma is important, as they become pharmacological targets for the discovery of new drugs and/or pharmacological tools that effectively help the pharmacotherapeutic follow-up of this disease, as well as the more specific mechanisms involved in worsening asthma.

Slowed Intestinal Transit Induced by Less Mucus in Intestinal Goblet Cell Piezo1-Deficient Mice through Impaired Epithelial Homeostasis

Mucus secreted by goblet cells (GCs) may play an important role in intestinal transit function. Our previous study found that Piezo1 protein is essential for GC function; however, the effect of GC Piezo1 on intestinal transit function is unclear. Our study aimed to investigate the effect of Piezo1 in GCs on intestinal transit and the potential mechanism. We compared intestinal mucus, fecal form, intestinal transit time, intestinal epithelial cell composition, and stem cell function in WT and GC-specific Piezo1-deficient (Piezo1ΔGC) mice. Our results revealed a correlation between mucus and intestinal transit: the less mucus there was, the slower the intestinal transit. Piezo1 deficiency in GCs led to decreased mucus synthesis and also disrupted the ecological niche of colon stem cells (CSCs). Through organoid culture, we found that the capacity of proliferation and differentiation in Piezo1ΔGC mouse CSCs was significantly decreased, which also led to a reduced source of GCs. Further studies found that the reduced Wnt and Notch signals in colon crypts might be the potential mechanism. These results indicated the importance of GC Piezo1 in intestinal transit function, which acts by maintaining the homeostasis of intestinal epithelial cells and mucus.

3D porous sodium alginate-silk fibroin composite bead based in vitro tumor model for screening of anti-cancer drug and induction of magneto-apoptosis

The development of 3D scaffold-based in vitro tumor models can help to address the limitations of cell culture and animal models for designing and screening anticancer drugs. In this study, in vitro 3D tumor models using sodium alginate (SA) and sodium alginate/silk fibroin (SA/SF) porous beads were developed. The beads were non-toxic and A549 cells had a high tendency to adhere, proliferate, and form tumor-like aggregates within SA/SF beads. The 3D tumor model based on these beads had better efficacy for anti-cancer drug screening than the 2D cell culture model. Additionally, the SA/SF porous beads loaded with superparamagnetic iron oxide nanoparticles were used to explore their magneto-apoptosis ability. The cells exposed to a high magnetic field were more likely to undergo apoptosis than those exposed to a low magnetic field. These findings suggest that the SA/SF porous beads and SPIONs loaded SA/SF porous beads-based tumor models could be useful for drug screening, tissue engineering, and mechanobiology studies.

Jatrorrhizine inhibits Piezo1 activation and reduces vascular inflammation in endothelial cells

Vascular inflammation is a common pathological basis underlying many cardiovascular diseases. As such, the treatment of vascular inflammation has attracted increasing attention. The Piezo1 pathway has long been shown to play an important role in the development of vascular inflammation. Jatrorrhizine (Jat) is an effective component of Rhizoma Coptidis. It is commonly used in the treatment of inflammatory diseases and is a potential drug for the treatment of vascular inflammation. However, its mechanism of action on vascular inflammation remains unclear, as is the effect of Jat on Piezo1. Therefore, we conducted a series of studies on the effect of jatrorrhizine on vascular inflammation in vivo and in vitro. In this study, the effect of Jat treatment on H₂O₂-induced endothelial cell inflammation was investigated in vitro, and the potential mechanism of Jat was explored. In in vivo experiments, we investigated the effect of jatrorrhizine on vascular inflammation induced by carotid artery ligation and its effect on the Piezo1 signaling pathway. We found that Jat could reduce the severity of carotid intimal hyperplasia and local vascular inflammation in mice. In the H₂O₂-induced inflammation model, cell proliferation and migration were significantly inhibited, and the expression of pro-inflammatory factors was reduced. Importantly, the addition of Jat to endothelial Piezo1 knockout did not produce further significant inhibition. We believe that the role of Jat in the treatment of vascular inflammation may be related to Piezo1. And we believe that Jat has great potential in the treatment of vascular inflammation and cardiovascular diseases.

TOLLIP-mediated autophagic degradation pathway links the VCP-TMEM63A-DERL1 signaling axis to triple-negative breast cancer progression

Triple-negative breast cancer (TNBC) is the most challenging breast cancer subtype to treat due to the lack of effective targeted therapies. Transmembrane (TMEM) proteins represent attractive drug targets for cancer therapy, but biological functions of most members of the TMEM family remain unknown. Here, we report for the first time that TMEM63A (transmembrane protein 63A), a poorly characterized TMEM protein with unknown functions in human cancer, functions as a novel oncogene to promote TNBC cell proliferation, migration, and invasion in vitro and xenograft tumor growth and lung metastasis in vivo. Mechanistic investigations revealed that TMEM63A localizes in endoplasmic reticulum (ER) and lysosome membranes, and interacts with VCP (valosin-containing protein) and its cofactor DERL1 (derlin 1). Furthermore, TMEM63A undergoes autophagy receptor TOLLIP-mediated autophagic degradation and is stabilized by VCP through blocking its lysosomal degradation. Strikingly, TMEM63A in turn stabilizes oncoprotein DERL1 through preventing TOLLIP-mediated autophagic degradation. Notably, pharmacological inhibition of VCP by CB-5083 or knockdown of DERL1 partially abolishes the oncogenic effects of TMEM63A on TNBC progression both in vitro and in vivo. Collectively, these findings uncover a previously unknown functional and mechanistic role for TMEM63A in TNBC progression and provide a new clue for targeting TMEM63A-driven TNBC tumors by using a VCP inhibitor.Abbreviations: ATG16L1, autophagy related 16 like 1; ATG5, autophagy related 5; ATP5F1B/ATP5B, ATP synthase F1 subunit beta; Baf-A1, bafilomycin A₁; CALCOCO2/NDP52, calcium binding and coiled-coil domain 2; CANX, calnexin; DERL1, derlin 1; EGFR, epidermal growth factor receptor; ER, endoplasmic reticulum; ERAD, endoplasmic reticulum-associated degradation; HSPA8, heat shock protein family A (Hsp70) member 8; IP, immunoprecipitation; LAMP2A, lysosomal associated membrane protein 2; NBR1, NBR1 autophagy cargo receptor; OPTN, optineurin; RT-qPCR, reverse transcription-quantitative PCR; SQSTM1/p62, sequestosome 1; TAX1BP1, Tax1 binding protein 1; TMEM63A, transmembrane protein 63A; TNBC, triple-negative breast cancer; TOLLIP, toll interacting protein; VCP, valosin containing protein.

Orthodontic Compression Enhances Macrophage M2 Polarization via Histone H3 Hyperacetylation

Orthodontic tooth movement is a complex periodontal remodeling process triggered by compression that involves sterile inflammation and immune responses. Macrophages are mechanically sensitive immune cells, but their role in orthodontic tooth movement is unclear. Here, we hypothesize that orthodontic force can activate macrophages, and their activation may be associated with orthodontic root resorption. After force-loading and/or adiponectin application, the migration function of macrophages was tested via scratch assay, and Nos2, Il1b, Arg1, Il10, ApoE, and Saa3 expression levels were detected using qRT-PCR. Furthermore, H3 histone acetylation was measured using an acetylation detection kit. The specific inhibitor of H3 histone, I-BET762, was deployed to observe its effect on macrophages. In addition, cementoblasts were treated with macrophage-conditioned medium or compression force, and OPG production and cellular migration were measured. We further detected Piezo1 expression in cementoblasts via qRT-PCR and Western-blot, and its effect on the force-induced impairment of cementoblastic functions was also analyzed. Compressive force significantly inhibited macrophage migration. Nos2 was up-regulated 6 h after force-loading. Il1b, Arg1, Il10, Saa3, and ApoE increased after 24 h. Meanwhile, higher H3 histone acetylation was detected in the macrophages subjected to compression, and I-BET762 dampened the expression of M2 polarization markers (Arg1 and Il10). Lastly, even though the activated macrophage-conditioned medium showed no effect on cementoblasts, compressive force directly impaired cementoblastic function by enhancing mechanoreceptor Piezo1. Compressive force activates macrophages; specifically, it causes M2 polarization via H3 histone acetylation in the late stage. Compression-induced orthodontic root resorption is macrophage-independent, but it involves the activation of mechanoreceptor Piezo1.

PIEZO1-Related Physiological and Pathological Processes in CNS: Focus on the Gliomas

PIEZO1 is ubiquitously expressed in cells in different kinds of tissues throughout the body, which can sense physical or mechanical stimuli and translate them into intracellular electrochemical signals to regulate organism functions. In particular, PIEZO1 appears in complex interactive regulatory networks as a central node, governing normal and pathological functions in the body. However, the effect and mechanism of the activation or expression of PIEZO1 in diseases of the central nervous system (CNS) remain unclear. On one hand, in CNS diseases, pathophysiological processes in neurons and glial are often accompanied by variations in the mechanical properties of the cellular and extracellular matrix stiffness. The expression of PIEZO1 can therefore be upregulated, in responding to mechanical stimulation, to drive the biological process in cells, which in turns indirectly affects the cellular microenvironment, resulting in alterations of the cellular status. On the other hand, it may have contradictory effects with the change of active patterns and/or subcellular location. This review highlights the biological processes involved with PIEZO1 in CNS cells, with special emphasis on its multiple roles in glioma-associated phenotypes. In conclusion, PIEZO1 can be used as an indicator to assess the malignancy and prognosis of patients with gliomas, as well as a therapeutic target for clinical application following fully exploring the potential mechanism of PIEZO1 in CNS diseases.

Mechanosensitive Ion Channels and Their Role in Cancer Cells

Mechanical forces are an inherent element in the world around us. The effects of their action can be observed both on the macro and molecular levels. They can also play a prominent role in the tissues and cells of animals due to the presence of mechanosensitive ion channels (MIChs) such as the Piezo and TRP families. They are essential in many physiological processes in the human body. However, their role in pathology has also been observed. Recent discoveries have highlighted the relationship between these channels and the development of malignant tumors. Multiple studies have shown that MIChs mediate the proliferation, migration, and invasion of various cancer cells via various mechanisms. This could show MIChs as new potential biomarkers in cancer detection and prognosis and interesting therapeutic targets in modern oncology. Our paper is a review of the latest literature on the role of the Piezo1 and TRP families in the molecular mechanisms of carcinogenesis in different types of cancer.

Piezo1 activation facilitates ovarian cancer metastasis via Hippo/YAP signaling axis

Ovarian cancer (OC) is a highly malignant cancer with great metastatic potential. Here we aimed to investigate the role of Piezo1, a gene related to the mechanical environment of the tumor, in promoting the metastasis of OC. We performed Piezo1 knockdown in A-1847 cells using small hairpin RNAs, and the cells were inoculated subcutaneously in nude mice. Piezo1 knockdown decreased the tumor growth rate of OC tumor xenografts in mice and reduced cell migration in vitro. Metastasis in the lung was also attenuated after Piezo1 knockdown as revealed by HE staining of the lung tissues, which was concomitant with downregulation of E-Cadherin and vimentin and upregulation of N-Cadherin analyzed using western blot analysis, suggesting suppressed epithelial-to-mesenchymal transition. Migration of Piezo1-knockdown cells was also analyzed for their migratory capabilities using the scratch assay. We also analyzed the key proteins in the Hippo/YAP signaling pathway using western blot after treating A-1847 and 3AO cells with a Piezo1 inducer, Yoda1. Piezo1 inducer Yoda1 activated Hippo/YAP signal in OC cells. In conclusion, Piezo1 is overexpressed in OC tissues and contributes to OC tumor growth and metastasis. Suppression of Piezo1 is a potential therapeutic strategy for OC.

Biological role of matrix stiffness in tumor growth and treatment

In recent years, the biological role of changes in physical factors in carcinogenesis and progression has attracted increasing attention. Matrix stiffness, also known as ECM stress, is a critical physical factor of tumor microenvironment and remains alternating during carcinogenesis as a result of ECM remodeling through activation of cancer-associated fibroblasts and extracellular collagen accumulation, crosslinking and fibrosis. Different content and density of extracellular collagen in ECM endows matrix with varying stiffness. Physical signals induced by matrix stiffness are transmitted to tumor cells primarily by the integrins receptor family and trigger a series of mechanotransduction that result in changes in tumor cell morphology, proliferative capacity, and invasive ability. Importantly, accumulating evidence revealed that changes in matrix stiffness in tumor tissues greatly control the sensitivity of tumor cells in response to chemotherapy, radiotherapy, and immunotherapy through integrin signaling, YAP signaling, and related signaling pathways. Here, the present review analyzes the current research advances on matrix stiffness and tumor cell behavior with a view to contributing to tumor cell growth and treatment, with the hope of improving the understanding of the biological role of matrix stiffness in tumors.

Mechanosensitive Ion Channel PIEZO1 Signaling in the Hall-Marks of Cancer: Structure and Functions

Simple Summary

Tumor cells obtain various unique characteristics, which known as hallmarks of cancers, including sustained proliferative signaling, apoptosis resistance, and metastasis. These characteristics are crucial for tumor cells survival and for supporting their rapid growth. Studies have revealed that tumorigenesis is also accompanied by alteration in mechanical properties. Tumor cells could sense various mechanical forces, such as compressive force, shear stress, and portal vein pressure, which in turn could affect tumor progression. Piezo1 is a mechanically sensitive ion channel protein that can be activated mechanically, and is closely related to various diseases. Recent studies showed that Piezo1 is overexpressed in numerous tumors and is associated with poor prognosis. Furthermore, previous studies revealed that Piezo1 mediates these cancer hallmarks, and thus links up mechanical forces with tumor progression. Therefore, the discovery of Piezo1 provides a new insight for elucidating the mechanism of tumor progression under a mechanical microenvironment.

Abstract

Tumor cells alter their characteristics and behaviors during tumorigenesis. These characteristics, known as hallmarks of cancer, are crucial for supporting their rapid growth, need for energy, and adaptation to tumor microenvironment. Tumorigenesis is also accompanied by alteration in mechanical properties. Cells in tumor tissue sense mechanical signals from the tumor microenvironment, which consequently drive the acquisition of hallmarks of cancer, including sustained proliferative signaling, evading growth suppressors, apoptosis resistance, sustained angiogenesis, metastasis, and immune evasion. Piezo-type mechanosensitive ion channel component 1 (Piezo1) is a mechanically sensitive ion channel protein that can be activated mechanically and is closely related to various diseases. Recent studies showed that Piezo1 mediates tumor development through multiple mechanisms, and its overexpression is associated with poor prognosis. Therefore, the discovery of Piezo1, which links-up physical factors with biological properties, provides a new insight for elucidating the mechanism of tumor progression under a mechanical microenvironment, and suggests its potential application as a tumor marker and therapeutic target. In this review, we summarize current knowledge regarding the role of Piezo1 in regulating cancer hallmarks and the underlying molecular mechanisms. Furthermore, we discuss the potential of Piezo1 as an antitumor therapeutic target and the limitations that need to be overcome.

The role of mechanosensitive ion channels in the gastrointestinal tract

Mechanosensation is essential for normal gastrointestinal (GI) function, and abnormalities in mechanosensation are associated with GI disorders. There are several mechanosensitive ion channels in the GI tract, namely transient receptor potential (TRP) channels, Piezo channels, two-pore domain potassium (K2p) channels, voltage-gated ion channels, large-conductance Ca²⁺-activated K⁺ (BKCa) channels, and the cystic fibrosis transmembrane conductance regulator (CFTR). These channels are located in many mechanosensitive intestinal cell types, namely enterochromaffin (EC) cells, interstitial cells of Cajal (ICCs), smooth muscle cells (SMCs), and intrinsic and extrinsic enteric neurons. In these cells, mechanosensitive ion channels can alter transmembrane ion currents in response to mechanical forces, through a process known as mechanoelectrical coupling. Furthermore, mechanosensitive ion channels are often associated with a variety of GI tract disorders, including irritable bowel syndrome (IBS) and GI tumors. Mechanosensitive ion channels could therefore provide a new perspective for the treatment of GI diseases. This review aims to highlight recent research advances regarding the function of mechanosensitive ion channels in the GI tract. Moreover, it outlines the potential role of mechanosensitive ion channels in related diseases, while describing the current understanding of interactions between the GI tract and mechanosensitive ion channels.

Piezo1 Channel as a Potential Target for Hindering Cardiac Fibrotic Remodeling

Fibrotic tissues share many common features with neoplasms where there is an increased stiffness of the extracellular matrix (ECM). In this review, we present recent discoveries related to the role of the mechanosensitive ion channel Piezo1 in several diseases, especially in regulating tumor progression, and how this can be compared with cardiac mechanobiology. Based on recent findings, Piezo1 could be upregulated in cardiac fibroblasts as a consequence of the mechanical stress and pro-inflammatory stimuli that occurs after myocardial injury, and its increased activity could be responsible for a positive feedback loop that leads to fibrosis progression. The increased Piezo1-mediated calcium flow may play an important role in cytoskeleton reorganization since it induces actin stress fibers formation, a well-known characteristic of fibroblast transdifferentiation into the activated myofibroblast. Moreover, Piezo1 activity stimulates ECM and cytokines production, which in turn promotes the phenoconversion of adjacent fibroblasts into new myofibroblasts, enhancing the invasive character. Thus, by assuming the Piezo1 involvement in the activation of intrinsic fibroblasts, recruitment of new myofibroblasts, and uncontrolled excessive ECM production, a new approach to blocking the fibrotic progression can be predicted. Therefore, targeted therapies against Piezo1 could also be beneficial for cardiac fibrosis.

A Pancancer Study of PIEZO1 as a Prognosis and Immune Biomarker of Human Tumors

PIEZO1, a mechanosensitive ion channel protein, has been identified in the correlation between several cancers. However, the systematic pancancer study of PIEZO1 still lacks. We examined PIEZO1 across thirty-three types of cancers to explore its role in prognosis and immunological function for the first time. Based on the open databases TCGA, GTEx and CPTAC, PIEZO1 has been demonstrated to be differentially expressed in most cancers compared to adjacent normal tissues. The distinct correlation between PIEZO1 and prognosis of tumor patients was explored by GEPIA2. Genetic alteration of PIEZO1 in the TCGA tumors showed that mutation is the alteration which is linked to OS, DSS, DFS and PFS in some tumors. Alterations of protein phosphorylation levels were detected in some cancers based on the CPTAC dataset. PIEZO1 expression was linked with immune cell infiltration, such as endothelial cell and cancer-associated fibroblast. Finally, KEGG and GO enrichment analyses were applied to investigate the molecular mechanism of PIEZO1. Our first pancancer analysis illustrated the roles of PIEZO1 in different types of tumors.

Identification of Key Genes and Pathways Associated with PIEZO1 in Bone-Related Disease Based on Bioinformatics

PIEZO1 is a mechano-sensitive ion channel that can sense various forms of mechanical stimuli and convert them into biological signals, affecting bone-related diseases. The present study aimed to identify key genes and signaling pathways in Piezo1-regulated bone-related diseases and to explain the potential mechanisms using bioinformatic analysis. The differentially expressed genes (DEGs) in tendon, femur, and humerus bone tissue; cortical bone; and bone-marrow-derived macrophages were identified with the criteria of |log2FC| > 1 and adjusted p-value < 0.05 analysis based on a dataset from GSE169261, GSE139121, GSE135282, and GSE133069, respectively, and visualized in a volcano plot. Venn diagram analyses were performed to identify the overlapping DEGs expressed in the above-mentioned tissues. Gene Ontology (GO) enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, protein−protein interaction (PPI) analysis, and module analysis were also conducted. Furthermore, qRT-PCR was performed to validate the above results using primary chondrocytes. As a result, a total of 222 overlapping DEGs and 12 mostly overlapping DEGs were identified. Key Piezo1-related genes, such as Lcn2, Dkk3, Obscn, and Tnnt1, were identified, and pathways, such as Wnt/β-catenin and PI3k-Akt, were also identified. The present informatic study provides insight, for the first time, into the potential therapeutic targets of Piezo1-regulated bone-related diseases

miR-10b-5p-mediated upregulation of PIEZO1 predicts poor prognosis and links to purine metabolism in breast cancer

BACKGROUND

Increasing evidence has reported the critical roles of PIEZO1 in organism. However, the knowledge of PIEZO1 in human cancers is still inadequate.

METHODS

In silico analyses and experimental validation were performed to analyze PIEZO1's expression, prognostic values and potential upstream/downstream mechanism in breast cancer.

RESULTS

PIEZO1 was significantly overexpressed in human breast cancer cell lines and tissue samples. PIEZO1 expression was statistically positively associated with malignant progression and short survival of breast cancer. miR-10b-5p downregulation was partially responsible for PIEZO1 upregulation in breast cancer. Further exploration revealed that PIEZO1 might exert its function by regulating purine metabolism (especially GUK1, POLD1 and APRT) in breast cancer.

CONCLUSIONS

Collectively, the current study elucidated an important role of PIEZO1 in breast cancer and providing key clues for identifying PIEZO1 as a therapeutic target and prognostic biomarker in breast cancer.