Piezo1 Knockdown Research Articles

The Mechanosensitive Ion Channel Piezo1 Significantly Mediates InVitro Ultrasonic Stimulation of Neurons.

SummaryUltrasound brain stimulation is a promising modality for probing brain function and treating brain disease non-invasively and with high spatiotemporal resolution. However, the mechanism underlying its effects remains unclear. Here, we examine the role that the mouse piezo-type mechanosensitive ion channel component 1 (Piezo1) plays in mediating the in vitro effects of ultrasound in mouse primary cortical neurons and a neuronal cell line. We show that ultrasound alone could activate heterologous and endogenous Piezo1, initiating calcium influx and increased nuclear c-Fos expression in primary neurons but not when pre-treated with a Piezo1 inhibitor. We also found that ultrasound significantly increased the expression of the important proteins phospho-CaMKII, phospho-CREB, and c-Fos in a neuronal cell line, but Piezo1 knockdown significantly reduced this effect. Our findings demonstrate that the activity of mechanosensitive ion channels such as Piezo1 stimulated by ultrasound is an important contributor to its ability to stimulate cells in vitro.

PIEZO1 and TRPV4, which Are Distinct Mechano-Sensors in the Osteoblastic MC3T3-E1 Cells, Modify Cell-Proliferation.

Mechanical-loading and unloading can modify osteoblast functioning. Ca2+ signaling is one of the earliest events in osteoblasts to induce a mechanical stimulus, thereby demonstrating the importance of the underlying mechanical sensors for the sensation. Here, we examined the mechano-sensitive channels PIEZO1 and TRPV4 were involved in the process of mechano-sensation in the osteoblastic MC3T3-E1 cells. The analysis of mRNA expression revealed a high expression of Piezo1 and Trpv4 in these cells. We also found that a PIEZO1 agonist, Yoda1, induced Ca2+ response and activated cationic currents in these cells. Ca2+ response was elicited when mechanical stimulation (MS), with shear stress, was induced by fluid flow in the MC3T3-E1 cells. Gene knockdown of Piezo1 in the MC3T3-E1 cells, by transfection with siPiezo1, inhibited the Yoda1-induced response, but failed to inhibit the MS-induced response. When MC3T3-E1 cells were transfected with siTrpv4, the MS-induced response was abolished and Yoda1 response was attenuated. Moreover, the MS-induced response was inhibited by a TRPV4 antagonist HC-067047 (HC). Yoda1 response was also inhibited by HC in MC3T3-E1 cells and HEK cells, expressing both PIEZO1 and TRPV4. Meanwhile, the activation of PIEZO1 and TRPV4 reduced the proliferation of MC3T3-E1, which was reversed by knockdown of PIEZO1, and TRPV4, respectively. In conclusion, TRPV4 and PIEZO1 are distinct mechano-sensors in the MC3T3-E1 cells. However, PIEZO1 and TRPV4 modify the proliferation of these cells, implying that PIEZO1 and TRPV4 may be functional in the osteoblastic mechano-transduction. Notably, it is also found that Yoda1 can induce TRPV4-dependent Ca2+ response, when both PIEZO1 and TRPV4 are highly expressed.

Piezo1 induced apoptosis of type II pneumocytes during ARDS

ObjectiveThe mechanisms of lung injury in acute respiratory distress syndrome (ARDS) are not well understood.Piezo1 was recently identified as a mechanotransduction protein. The present study found the expression of Piezo1 in type II pneumocytes and investigated its role in mediating ARDS-related lung injury.MethodsSprague-Dawley rats were used to establish an ARDS model, the expression of Piezo1,lung injuries, apoptosis as well as calcium influx were assessed.ResultsPiezo1 was expressed in type II pneumocytes as shown by immunofluorescence staining and expression was increased in the ARDS model. Knockdown of Piezo1 reduced apoptosis which was related to the elevation of Bcl-2.Calcium influx played a vital role in Piezo1-induced apoptosis.ConclusionPiezo1 was expressed in type II pneumocytes. Mechanical stretch of alveoli during ARDS induced activation of the Piezo1 channel,which resulted in calcium influx. The increased intracellular Ca2+ induced the apoptosis of type II pneumocytes, which may be related to the Bcl-2 pathway.

Shear stress-induced nuclear shrinkage through activation of Piezo1 channels in epithelial cells.

The cell nucleus responds to mechanical cues with changes in size, morphology and motility. Previous work has shown that external forces couple to nuclei through the cytoskeleton network, but we show here that changes in nuclear shape can be driven solely by calcium levels. Fluid shear stress applied to MDCK cells caused the nuclei to shrink through a Ca2+-dependent signaling pathway. Inhibiting mechanosensitive Piezo1 channels through treatment with GsMTx4 prevented nuclear shrinkage. Piezo1 knockdown also significantly reduced the nuclear shrinkage. Activation of Piezo1 with the agonist Yoda1 caused similar nucleus shrinkage in cells not exposed to shear stress. These results demonstrate that the Piezo1 channel is a key element for transmitting shear force input to nuclei. To ascertain the relative contribution of Ca2+ to cytoskeleton perturbation, we examined F-actin reorganization under shear stress and static conditions, and showed that reorganization of the cytoskeleton is not necessary for nuclear shrinkage. These results emphasize the role of the mechanosensitive channels as primary transducers in force transmission to the nucleus.

Loss of stretch-activated channels, PIEZOs, accelerates non-small cell lung cancer progression and cell migration.

PIEZO channels are stretch-activated channels involved in wound sealing and cell proliferation in many cell types. A recent study focussing on lung cancer (LC), using next-generation sequencing analysis, has indicated that PIEZO functions were implicated in LC development. However, the expression and role of PIEZO channels in non-small cell LC (NSCLC) progression require elucidation. In the current study, we investigated the gene expression and alteration frequency in human NSCLC tissue, accessed the prognostic roles of PIEZO channels in NSCLC patients, and further studied the effect of PIEZOs in NSCLC cell proliferation and tumor growth in vivo. The mRNA expression of PIEZO1 and 2 was clearly decreased in NSCLC tumor tissue compared with that in matched adjacent non-tumor tissue. In human NSCLC tissues, PIEZO1 gene expression exhibits a highly deep deletion rate, and PIEZO2 mainly exhibits mutation in gene expression. High mRNA expression of PIEZO channels was found to correlate with better overall survival (OS) for NSCLC patients, especially for patients with lung adenocarcinoma (LUAD), but not for patients with lung squamous cell carcinoma (LUSC). The prognostic role of PIEZO channels was more sensitive in female patients than male patients, and more sensitive in patients at earlier stages than patients at latter stages. Knockdown of PIEZO1 or PIEZO2 in NSCLC cells significantly promoted cell migration in vitro and tumor growth in vivo. These results indicate the critical prognostic values of the PIEZO channels in NSCLC. This information will be beneficial to understand the pathological mechanism of NSCLC and to generate effective therapeutic approaches for NSCLC patients.

Piezo1 incorporates mechanical force signals into the genetic program that governs lymphatic valve development and maintenance.

The lymphatic system plays crucial roles in tissue homeostasis, lipid absorption, and immune cell trafficking. Although lymphatic valves ensure unidirectional lymph flows, the flow itself controls lymphatic valve formation. Here, we demonstrate that a mechanically activated ion channel Piezo1 senses oscillating shear stress (OSS) and incorporates the signal into the genetic program controlling lymphatic valve development and maintenance. Time-controlled deletion of Piezo1 using a pan-endothelial Cre driver (Cdh5[PAC]-CreERT2) or lymphatic-specific Cre driver (Prox1-CreERT2) equally inhibited lymphatic valve formation in newborn mice. Furthermore, Piezo1 deletion in adult lymphatics caused substantial lymphatic valve degeneration. Piezo1 knockdown in cultured lymphatic endothelial cells (LECs) largely abrogated the OSS-induced upregulation of the lymphatic valve signature genes. Conversely, ectopic Piezo1 overexpression upregulated the lymphatic valve genes in the absence of OSS. Remarkably, activation of Piezo1 using chemical agonist Yoda1 not only accelerated lymphatic valve formation in animals, but also triggered upregulation of some lymphatic valve genes in cultured LECs without exposure to OSS. In summary, our studies together demonstrate that Piezo1 is the force sensor in the mechanotransduction pathway controlling lymphatic valve development and maintenance, and Piezo1 activation is a potentially novel therapeutic strategy for congenital and surgery-associated lymphedema.

Rapid flow-induced activation of Gαq/11 is independent of Piezo1 activation.

Endothelial cell (EC) mechanochemical transduction is the process by which mechanical stimuli are sensed by ECs and transduced into biochemical signals and ultimately into physiological responses. Identifying the mechanosensor/mechanochemical transducer(s) and describing the mechanism(s) by which they receive and transmit the signals has remained a central focus within the field. The heterotrimeric G protein, Gαq/11, is proposed to be part of a macromolecular complex together with PECAM-1 at EC junctions and may constitute the mechanochemical transducer as it is rapidly activated within seconds of flow onset. The mechanically activated cation channel Piezo1 has recently been implicated due to its involvement in mediating early responses, such as calcium and ATP release. Here, we investigate the role of Piezo1 in rapid shear stress-induced Gαq/11 activation. We show that flow-induced dissociation of Gαq/11 from PECAM-1 in ECs at 15 s is abrogated by BIM-46187, a selective inhibitor of Gαq/11 activation, suggesting that Gαq/11 activation is required for PECAM-1/Gαq/11 dissociation. Although siRNA knockdown of Piezo1 caused a dramatic decrease in PECAM-1/Gαq/11 association in the basal condition, it had no effect on flow-induced dissociation. Interestingly, siRNA knockdown of Piezo1 caused a marked decrease in PECAM-1 expression. Additionally, selective blockade of Piezo1 with ion channel inhibitors had no effect on flow-induced PECAM-1/Gαq/11 dissociations. Lastly, flow onset caused increased association of Gβ1 with Piezo1 as well as with the p101 subunit of phosphoinositide 3-kinase, which were both blocked by the Gβγ inhibitor gallein. Together, our results indicate that flow-induced activation of Piezo1 is not upstream of G protein activation.

Piezo1 Mediated Ca2+ Signaling Causes Nuclear Shrinkage under Fluid Shear Stress

Nuclei of cells respond to local mechanical cues with changes in their size, morphology, and motility, to maintain tissue homeostasis and proper functions. Previous studies indicated that the external forces are coupled to nuclei through the surrounding cytoskeleton network linked to the nuclear envelope, but the molecules that directly interact with outside environments are unclear. Here we show that the fluid shear stress applied to MDCK cells caused the nucleus to shrink through a Ca2+ dependent signaling pathway. Inhibiting Ca2+ permeable mechanosensitive Piezo1 channels, with the specific inhibitor GsMTx4, eliminated the nuclear changes. Piezo1 knockdown with miRNA that targets Piezo1 significantly reduced the nuclear shrinkage under shear stress. Activation of Piezo1 with Yoda1 caused similar nucleus shrinkage without shear stress. These results demonstrate that Piezo1 channel is accountable for transmitting the shear force input to nuclei via Ca2+ signaling. To assess the relative contributions of Ca2+ and cytoskeleton reorganization on force transduction, we examined F-actin reorganization under shear stress and static conditions, and showed that reorganization is not necessary for the nucleus shrinkage. These results emphasize the role of the mechanosensitive channels as primary transducers in force transmission to the nucleus.

Piezo1 channels are mechanosensors in human fetoplacental endothelial cells

STUDY QUESTIONDoes the shear stress sensing ion channel subunit Piezo1 have an important mechanotransduction role in human fetoplacental endothelium?SUMMARY ANSWERPiezo1 is present and functionally active in human fetoplacental endothelial cells, and disruption of Piezo1 prevents the normal response to shear stress.WHAT IS KNOWN ALREADYShear stress is an important stimulus for maturation and function of placental vasculature but the molecular mechanisms by which the force is detected and transduced are unclear. Piezo1 channels are Ca2+-permeable non-selective cationic channels which are critical for shear stress sensing and maturation of murine embryonic vasculature.STUDY DESIGN, SAMPLES/MATERIALS, METHODSWe investigated the relevance of Piezo1 to placental vasculature by studying human fetoplacental endothelial cells (FpECs) from healthy pregnancies. Endothelial cells were isolated from placental cotyledons and cultured, for the study of tube formation and cell alignment to shear stress. In addition, human placental arterial endothelial cells were isolated and studied immediately by patch-clamp electrophysiology.MAIN RESULTS AND THE ROLE OF CHANCEThe synthetic Piezo1 channel agonist Yoda1 caused strong elevation of the intracellular Ca2+ concentration with a 50% effect occurring at about 5.4 μM. Knockdown of Piezo1 by RNA interference suppressed the Yoda1 response, consistent with it being mediated by Piezo1 channels. Alignment of cells to the direction of shear stress was also suppressed by Piezo1 knockdown without loss of cell viability. Patch-clamp recordings from freshly isolated endothelium showed shear stress-activated single channels which were characteristic of Piezo1.LIMITATIONS, REASONS FOR CAUTIONThe in vitro nature of fetoplacental endothelial cell isolation and subsequent culture may affect FpEC characteristics and PIEZO1 expression. In addition to Piezo1, alternative shear stress sensing mechanisms have been suggested in other systems and might also contribute in the placenta.WIDER IMPLICATIONS OF THE FINDINGSThese data suggest that Piezo1 is an important molecular determinant of blood flow sensitivity in the placenta. Establishing and manipulating the molecular mechanisms regulating shear stress sensing could lead to novel therapeutic strategies to improve blood flow in the placenta.LARGE-SCALE DATANot applicable.STUDY FUNDING/COMPETING INTEREST(S)LCM was funded by a Clinical Research Training Fellowship from the Medical Research Council and by the Royal College of Obstetricians and Gynaecologists, and has received support from a Wellcome Trust Institutional Strategic Support Fund. JS was supported by the Wellcome Trust and a BHF Intermediate Research Fellowship. HJG, CW, AJH and PJW were supported by PhD Studentships from BHF, BBSRC and the Leeds Teaching Hospitals Charitable Foundation respectively. All authors declare no conflict of interest.

PIEZO1 Channel Is a Potential Regulator of Synovial Sarcoma Cell-Viability.

Detection of mechanical stress is essential for diverse biological functions including touch, audition, and maintenance of vascular myogenic tone. PIEZO1, a mechano-sensing cation channel, is widely expressed in neuronal and non-neuronal cells and is expected to be involved in important biological functions. Here, we examined the possibility that PIEZO1 is involved in the regulation of synovial sarcoma cell-viability. Application of a PIEZO1 agonist Yoda1 effectively induced Ca2+ response and cation channel currents in PIEZO1-expressing HEK (HEK-Piezo1) cells and synovial sarcoma SW982 (SW982) cells. Mechanical stress, as well as Yoda1, induced the activity of an identical channel of conductance with 21.6 pS in HEK-Piezo1 cells. In contrast, Yoda1 up to 10 μM had no effects on membrane currents in HEK cells without transfecting PIEZO1. A knockdown of PIEZO1 with siRNA in SW982 cells abolished Yoda1-induced Ca2+ response and significantly reduced cell cell-viability. Because PIEZO1 is highly expressed in SW982 cells and its knockdown affects cell-viability, this gene is a potential target against synovial sarcoma.

PIEZO1 functions as a potential oncogene by promoting cell proliferation and migration in gastric carcinogenesis.

Gastric cancer (GC) is one of the most common malignancies in Asian areas. PIEZO1 has been implied to regulate epithelial homeostasis to play an important role in physiological processes. It is also related to tumor initiation and progression. However, the role of PIEZO1 has not yet been explored in GC. The expression of PIEZO1 in GC cell lines and primary samples was determined by qRT-PCR and Western blot. The clinical correlation of PIEZO1 in GC was evaluated by immunohistochemistry on tissue microarray. The oncogenic role of PIEZO1 was demonstrated in gastric tumorigenesis through a series of functional assays, including cell proliferation, cell invasion, and flow cytometry analysis. Drug sensitivity was also assessed by PIEZO1 knockdown experiment. PIEZO1 exhibited an upregulation in most of the GC cell lines and primary samples compared with non-tumorous gastric epithelial tissues. Increase of PIEZO1 was associated with poor disease specific survival. PIEZO1 knockdown led to inhibitory effect by suppressing cell proliferation and invasion and inhibiting xenograft formation. Decreased PIEZO1 enhanced the sensitivity of Cisplatin or 5-FU treatment. Morphological alteration was also observed in siPIEZO1 treated cells. GTP-Rac1 showed accumulated activated form, while total-RhoA was decreased accompanied with PIEZO1 knockdown. In the present study, PIEZO1 is required for cell proliferation, migration and invasion to promote GC progression. PIEZO1 also maintains cellular morphology related to GC cell motility by regulating the activity of Rho GTPase family members. Our data not only suggested a novel prognostic marker, but also provided a useful clinical therapeutic target for GC.

Rapid flow‐induced Gαq/11 activation occurs upstream of Piezo1 activation

Endothelial mechanotransduction is the process by which mechanical stimuli are sensed by endothelial cells (ECs) and transduced into biochemical signals and ultimately into physiological responses. Identifying the primary mechanosensor(s) and describing the mechanism(s) by which they receive and transmit the signals has remained a central focus within the field. The heterotrimeric G protein, Gαq/11, is proposed to be part of a macromolecular complex together with PECAM‐1 at the cell‐cell junction of ECs and may serve as a primary mechanosensor as it is rapidly activated within seconds of flow onset. The mechanically‐activated cation channel, Piezo1, has recently been implicated due in part to its involvement in mediating early responses, such as calcium influx and ATP release. In this study, we used in situ proximity ligation assay (PLA) to investigate the role of Piezo1 in the rapid shear stress‐induced activation of Gαq/11. We show that the flow‐induced dissociation of Gαq/11 from PECAM‐1 in ECs at 15 sec is abrogated by BIM‐46187, a specific inhibitor of Gαq/11 activation, suggesting that Gαq/11 activation is a prerequisite for PECAM‐1/Gαq/11 dissociation. Although siRNA knockdown of Piezo1 caused a dramatic decrease in PECAM‐1/Gαq/11 association in the basal condition, it had no effect on their flow‐induced dissociation. Interestingly, siRNA knockdown of Piezo1 caused a marked decrease in PECAM‐1 expression. Selective blockade of Piezo1 with ion channel inhibitors also had no effect on flow‐induced PECAM‐1/Gαq/11 dissociations despite having an inhibitory effect on Akt phosphorylation. Rapid flow (15 sec) also led to increased association of Gβ1 with Piezo1 as well as with the p101 subunit of phosphoinositide 3‐kinase (PI3K), which were both blocked in the presence of the Gβγ inhibitor, gallein. Taken together, our results indicate that flow‐induced activation of Piezo1 is downstream of G protein activation.Support or Funding InformationThis work was supported by NIH MERIT Award R37 HL040696 to J.A.F.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Cementogenesis is inhibited under a mechanical static compressive force via Piezo1.

To investigate whether Piezo1, a mechanotransduction gene mediates the cementogenic activity of cementoblasts under a static mechanical compressive force. Murine cementoblasts (OCCM-30) were exposed to a 2.0 g/cm2 static compressive force for 3, 6, 12, and 24 hours. Then the expression profile of Piezo1 and the cementogenic activity markers osteoprotegerin (Opg), osteopontin (Opn), osteocalcin (Oc), and protein tyrosine phosphataselike member A (Ptpla) were analyzed. Opg, Opn, Oc, and Ptpla expression was further measured after using siRNA to knock down Piezo1. Real-time PCR, Western blot, and cell proliferation assays were performed according to standard procedures. After mechanical stimulation, cell morphology and proliferation did not change significantly. The expression of Piezo1, Opg, Opn, Oc, and Ptpla was significantly decreased, with a high positive correlation between Opg and Piezo1 expression. After Piezo1 knockdown, the expression of Opg, Opn, Oc, and Ptpla was further decreased under mechanical stimulation. Cementogenic activity was inhibited in OCCM-30 cells under static mechanical force, a process that was partially mediated by the decrease of Piezo1. This study provides a new viewpoint of the pathogenesis mechanism of orthodontically induced root resorption and repair.

Piezo1 Transduces Extracellular Matrix Mechanical Cues to Direct Human Neural Stem Cell Fate

Mechanical cues are powerful determinants of cell behavior. For instance, mechanical properties of the extracellular matrix direct neural stem cell fate, determining whether they differentiate along a neuronal or glial lineage. The molecular mechanisms linking matrix mechanics to intracellular signaling pathways that influence lineage choice remain unclear. Here we use a multi-disciplinary approach to uncover a new player in mechanosensitive lineage commitment.We find that the stretch-activated ion channel, Piezo1, generates a mechanically-induced ionic current in human neural stem/progenitor cells. In the absence of externally applied mechanical force, Piezo1 activity is elicited by cellular traction forces and manifests as spontaneous calcium transients that vary with substrate stiffness. Piezo1 knockdown evoked nuclear exclusion of the mechanoreactive transcriptional co-activator Yap, suggesting a downstream effector of channel activity. Suppression of Piezo1 activity by the pharmacological inhibitor GsMTx-4 or by siRNA-mediated knockdown reduced neurogenesis and enhanced astrogenesis, demonstrating a role for Piezo1 in neural stem cell fate.We propose that the mechanically-gated ion channel Piezo1 is an important determinant of mechanosensitive lineage choice in neural stem cells and that it may play similar roles in other multipotent stem cells.

Piezo1 is as a novel trefoil factor family 1 binding protein that promotes gastric cancer cell mobility in vitro.

Trefoil factor family 1 (TFF1) is a member of the TFF-domain peptide family involved in epithelial restitution and cell motility. Recently, we screened Piezo1 as a candidate TFF1-binding protein. We aimed to confirm Piezo1 as a novel TFF1 binding protein and to assess the role of this interaction in mediating gastric cancer cell mobility. This interaction was confirmed by co-immunoprecipitation and co-localisation of TFF1 and Piezo1 in GES-1 cells. We used stable RNA interference to knockdown Piezo1 protein expression and restored the expression of TFF1 in the gastric cancer cell lines SGC-7901 and BGC-823. Cell motility was evaluated using invasion assay and migration assay in vitro. The expression levels of the integrin subunits β1, β5, α1 as well as the expression of β-catenin and E-cadherin were detected by Western blot. We demonstrate that TFF1, but not TFF2 or TFF3, bind to and co-localize with Piezo1 in the cytoplasm in vitro. TFF1 interacts with the C-terminal portion of the Piezo1 protein. Wound healing and trans-well assays demonstrated that the restored expression of TFF1 promoted cell mobility in gastric cancer cells, and this effect was attenuated by the knockdown of Piezo1. Western blots demonstrated the decreased expression of integrin β1 in Piezo1-knockdown cells. Our data demonstrate that Piezo1 is a novel TFF1 binding protein that is important for TFF1-mediated cell migration and suggest that this interaction may be a therapeutic target in the invasion and metastasis of gastric cancer.

Piezo1‐dependent stretch‐activated channels are inhibited by Polycystin‐2 in renal tubular epithelial cells

Mechanical forces associated with fluid flow and/or circumferential stretch are sensed by renal epithelial cells and contribute to both adaptive or disease states. Non-selective stretch-activated ion channels (SACs), characterized by a lack of inactivation and a remarkably slow deactivation, are active at the basolateral side of renal proximal convoluted tubules. Knockdown of Piezo1 strongly reduces SAC activity in proximal convoluted tubule epithelial cells. Similarly, overexpression of Polycystin-2 (PC2) or, to a greater extent its pathogenic mutant PC2-740X, impairs native SACs. Moreover, PC2 inhibits exogenous Piezo1 SAC activity. PC2 coimmunoprecipitates with Piezo1 and deletion of its N-terminal domain prevents both this interaction and inhibition of SAC activity. These findings indicate that renal SACs depend on Piezo1, but are critically conditioned by PC2.

Piezo1 plays a role in erythrocyte volume homeostasis

Mechanosensitivity is an inherent property of virtually all cell types, allowing them to sense and respond to physical environmental stimuli. Stretch-activated ion channels represent a class of mechanosensitive proteins which allow cells to respond rapidly to changes in membrane tension; however their identity has remained elusive. The piezo genes have recently been identified as a family of stretch-activated mechanosensitive ion channels. We set out to determine the role of piezo1 during zebrafish development. Here we report that morpholino-mediated knockdown of piezo1 impairs erythrocyte survival without affecting hematopoiesis or differentiation. Our results demonstrate that piezo1 is involved in erythrocyte volume homeostasis, disruption of which results in swelling/lysis of red blood cells and consequent anemia.

The Increasing Problem of Photosensitivity

Accumulating evidence has revealed the mechanosensitive ion channel protein Piezo1 is contributing to tumorigenesis. However, its role in hepatocellular carcinoma (HCC) remains unexplored. In this study, we demonstrated that Piezo1 was expressed in the HepG2 cell line and depletion of Piezo1 impaired proliferation and migration, as well as increased apoptosis in these cells. Using a Piezo1-specific activator, Yoda1, we identified that calcium entry induced by Yoda1 resulted in phosphorylation of JNK, p38, and ERK, thereby activating the mitogen-activated protein kinase (MAPK) pathway, in a dose- and time-dependent manner. More strikingly, Piezo1 activation integrated with YAP signaling to control the nuclear translocation of YAP and regulation of its target genes. JNK, p38, and ERK (MAPK signaling) regulated Yoda1-induced YAP activation. Consistent with the association of calpain with Piezo1, we also found that calpain activity was decreased by siRNA-mediated knockdown of Piezo1. In addition, the growth of HCC tumors was inhibited in Piezo1 haploinsufficient mice. Together, our findings establish that the Piezo1/MAPK/YAP signaling cascade is essential for HepG2 cell function. These results highlight the importance of Piezo1 in HCC and the potential utility of Piezo1 as a biomarker and therapeutic target.