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Biochimica Et Biophysica Acta.... Jan 2024To explore the novel function of MYO6 on Osteoclast differentiation and its joint destruction capacity in Rheumatoid arthritis mice model.
OBJECTIVES
To explore the novel function of MYO6 on Osteoclast differentiation and its joint destruction capacity in Rheumatoid arthritis mice model.
METHODS
We examined joint erosion in a collagen-induced arthritis (CIA) mouse model using micro-CT, with the mice having a MYO6 knockout background. Inflammatory cytokines were analyzed using an enzyme-linked immunosorbent assay (ELISA). In vitro, we investigated the osteoclastogenesis ability of bone marrow-derived macrophages isolated from MYO6 mice and their littermate controls, examining both morphological and functional differences. Furthermore, we explored podosome formation and endosome maturation using immunofluorescence staining.
RESULTS
We found that MYO6 deficiency attenuated arthritis development and bone destruction in CIA mice as well as impaired osteoclast differentiation by inhibiting NFATc1 induction. Our findings indicate that MYO6 is essential for the organization of podosomes by modulating the FAK/AKT and integrin-β3/Src pathways. MYO6 also mediates endosome transportation by regulating the expression of Rab5 and GM130. This may impact the maintenance and functionality of the ruffled border, as well as the regulation of autophagy in osteoclasts.
CONCLUSION
Our results demonstrated a critical function of MYO6 in osteoclast differentiation and its potential relevance in experimental arthritis.
Topics: Animals; Mice; Arthritis, Experimental; Arthritis, Rheumatoid; Disease Models, Animal; Macrophages; Osteoclasts; Osteogenesis
PubMed: 37816396
DOI: 10.1016/j.bbadis.2023.166902 -
Nature Communications Sep 2023The activation and accumulation of lung fibroblasts resulting in aberrant deposition of extracellular matrix components, is a pathogenic hallmark of Idiopathic Pulmonary...
The activation and accumulation of lung fibroblasts resulting in aberrant deposition of extracellular matrix components, is a pathogenic hallmark of Idiopathic Pulmonary Fibrosis, a lethal and incurable disease. In this report, increased expression of TKS5, a scaffold protein essential for the formation of podosomes, was detected in the lung tissue of Idiopathic Pulmonary Fibrosis patients and bleomycin-treated mice. Τhe profibrotic milieu is found to induce TKS5 expression and the formation of prominent podosome rosettes in lung fibroblasts, that are retained ex vivo, culminating in increased extracellular matrix invasion. Tks5 mice are found resistant to bleomycin-induced pulmonary fibrosis, largely attributed to diminished podosome formation in fibroblasts and decreased extracellular matrix invasion. As computationally predicted, inhibition of src kinase is shown to potently attenuate podosome formation in lung fibroblasts and extracellular matrix invasion, and bleomycin-induced pulmonary fibrosis, suggesting pharmacological targeting of podosomes as a very promising therapeutic option in pulmonary fibrosis.
Topics: Animals; Humans; Mice; Adaptor Proteins, Vesicular Transport; Bleomycin; Extracellular Matrix; Fibroblasts; Idiopathic Pulmonary Fibrosis; Podosomes; Proto-Oncogene Proteins pp60(c-src)
PubMed: 37735172
DOI: 10.1038/s41467-023-41614-x -
Science Signaling Sep 2023Alternative splicing regulates gene expression and functional diversity and is often dysregulated in human cancers. Here, we discovered that the long noncoding RNA...
Alternative splicing regulates gene expression and functional diversity and is often dysregulated in human cancers. Here, we discovered that the long noncoding RNA (lncRNA) MIR99AHG regulated alternative splicing to alter the activity of a chromatin remodeler and promote metastatic behaviors in colorectal cancer (CRC). MIR99AHG was abundant in invasive CRC cells and metastatic tumors from patients and promoted motility and invasion in cultured CRC cells. MIR99AHG bound to and stabilized the RNA splicing factor PTBP1, and this complex increased cassette exon inclusion in the mRNA encoding the chromatin remodeling gene . Specifically, MIR99AHG altered the nature of PTBP1 binding to the splice sites on intron 12 of pre-mRNA, thereby triggering a splicing switch from skipping to including exon 13 to produce the long isoform, SMARCA1-L. SMARCA1, but not SMARCA1-L, suppressed invadopodia formation, cell migration, and invasion. Analysis of CRC samples revealed that the abundance of transcript positively correlated with that of mRNA and PTBP1 protein and with poor prognosis in patients with CRC. Furthermore, TGF-β1 secretion from cancer-associated fibroblasts increased expression in CRC cells. Our findings identify an lncRNA that is induced by cues from the tumor microenvironment and that interacts with PTBP1 to regulate alternative splicing, potentially providing a therapeutic target and predictive biomarker for metastatic CRC.
Topics: Humans; Alternative Splicing; Chromatin; Colorectal Neoplasms; Heterogeneous-Nuclear Ribonucleoproteins; Podosomes; Polypyrimidine Tract-Binding Protein; RNA Splicing; RNA, Long Noncoding; Tumor Microenvironment
PubMed: 37725664
DOI: 10.1126/scisignal.adh4210 -
Journal of Lipid Research Nov 2023Phosphatidylserine (PS) is an acidic phospholipid that is involved in various cellular events. Heterologous dominant mutations have been identified in the gene encoding...
Phosphatidylserine (PS) is an acidic phospholipid that is involved in various cellular events. Heterologous dominant mutations have been identified in the gene encoding PS synthase 1 (PSS1) in patients with a congenital disease called Lenz-Majewski syndrome (LMS). Patients with LMS show various symptoms, including craniofacial/distal-limb bone dysplasia and progressive hyperostosis. The LMS-causing gain-of-function mutants of PSS1 (PSS1) have been shown to synthesize PS without control, but why the uncontrolled synthesis would lead to LMS is unknown. Here we investigated the effect of PSS1 on osteoclasts (OCs) to elucidate the causative mechanism of LMS. PSS1 did not affect the expression of OC-related genes but inhibited the formation, multinucleation, and activity of OCs. Especially, OCs expressing PSS1 showed abnormal patterns and dynamics of actin podosome clusters, which have roles in OC migration and fusion. PSS1 did not affect the level of PS but changed the acyl chain compositions of PS and phosphatidylethanolamine, and decreased the level of phosphatidylinositol. The introduction of a catalytically inactive mutation into PSS canceled the changes in phospholipids and the phenotypes observed in OCs expressing PSS1. A gain-of-function mutant of PSS2 (PSS2 R97K) also impaired OC formation and caused changes in phospholipid composition similar to the changes caused by PSS1. Our results suggest that uncontrolled PS synthesis by PSS1 causes changes in the quantity or fatty acid composition of certain phospholipid classes, impairing OC formation and function, which might be a cause of osteosclerosis in patients with LMS.
Topics: Humans; Abnormalities, Multiple; Intellectual Disability; Osteoclasts; Phospholipids
PubMed: 37714410
DOI: 10.1016/j.jlr.2023.100443 -
European Journal of Cell Biology Dec 2023Podosomes have been known for several decades as micron-sized, F-actin-rich structures that play a pivotal role in cell migration and invasion, as they are able to...
Podosomes have been known for several decades as micron-sized, F-actin-rich structures that play a pivotal role in cell migration and invasion, as they are able to mediate both cell-matrix attachment as well as extracellular matrix degradation. Particularly in monocytic cells, podosomes have been shown to fulfill a variety of additional functions such as sensing of substrate rigidity and topography, or cell-cell fusion. Increasing evidence now points to the involvement of podosome-like structures also during phagocytosis by immune cells such as macrophages, dendritic cells, and neutrophils. Here, we compare the different cell models and experimental set ups where "phagocytic podosomes" have been described. We also discuss the composition and architecture of these structures, their potential involvement in mechanosensing and particle disruption, as well as the pros and cons for addressing them as bona fide podosomes.
Topics: Podosomes; Actin Cytoskeleton; Actins; Macrophages; Phagocytosis
PubMed: 37625234
DOI: 10.1016/j.ejcb.2023.151356 -
Current Issues in Molecular Biology Aug 2023Successful treatment for any type of carcinoma largely depends on understanding the patterns of invasion and migration. For oral squamous cell carcinoma (OSCC), these...
Successful treatment for any type of carcinoma largely depends on understanding the patterns of invasion and migration. For oral squamous cell carcinoma (OSCC), these processes are not entirely understood as of now. Invadopodia and podosomes, called invadosomes, play an important role in cancer cell invasion and migration. Previous research has established that cortactin () is a major inducer of invadosome formation. However, less is known about the expression patterns of and other genes related to it or invadopodia formation in OSCC during tumor progression in particular. In this study, gene expression patterns of CTTN and various genes (n = 36) associated with invadopodia formation were analyzed to reveal relevant expression patterns and give a comprehensive overview of them. The genes were analyzed from a whole genome dataset of 83 OSCC samples relating to tumor size, grading, lymph node status, and UICC (Union for Internatioanl Cancer Control). The data revealed significant overexpression of 18 genes, most notably , (SRC proto-onocogene, non-receptor tyrosine kinase) (epidermal growth factor receptor), (spleen associated tyrosine kinase), (WASP like actin nucleation promotion factor), and (arrestin beta 1) due to their significant correlation with further tumor parameters. This study is one of the first to summarize the expression patterns of and related genes in a complex group of OSCC samples.
PubMed: 37623256
DOI: 10.3390/cimb45080437 -
Experimental Cell Research Oct 2023A critical challenge in the treatment of glioblastoma (GBM) is its highly invasive nature which promotes cell migration throughout the brain and hinders surgical...
A critical challenge in the treatment of glioblastoma (GBM) is its highly invasive nature which promotes cell migration throughout the brain and hinders surgical resection and effective drug delivery. GBM cells demonstrate augmented invasive capabilities following exposure to the current gold standard treatment of radiotherapy (RT) and concomitant and adjuvant temozolomide (TMZ), resulting in rapid disease recurrence. Elucidating the mechanisms employed by post-treatment invasive GBM cells is critical to the development of more effective therapies. In this study, we utilized a Nanostring® Cancer Progression gene expression panel to identify candidate genes that may be involved in enhanced GBM cell invasion after treatment with clinically relevant doses of RT/TMZ. Our findings identified thrombospondin-1 (THBS1) as a pro-invasive gene that is upregulated in these cells. Immunofluorescence staining revealed that THBS1 localised within functional matrix-degrading invadopodia that formed on the surface of GBM cells. Furthermore, overexpression of THBS1 resulted in enhanced GBM cell migration and secretion of MMP-2, which was reduced with silencing of THBS1. The preliminary data demonstrates that THBS1 is associated with invadopodia in GBM cells and is likely involved in the invadopodia-mediated invasive process in GBM cells exposed to RT/TMZ treatment. Therapeutic inhibition of THBS1-mediated invadopodia activity, which facilitates GBM cell invasion, should be further investigated as a treatment for GBM.
Topics: Humans; Glioblastoma; Podosomes; Neoplasm Recurrence, Local; Temozolomide; Brain
PubMed: 37591452
DOI: 10.1016/j.yexcr.2023.113743 -
Cell Death & Disease Aug 2023Tumor-derived exosomes and their contents promote cancer metastasis. Phosphoglycerate mutase 1 (PGAM1) is involved in various cancer-related processes. Nevertheless, the...
Tumor-derived exosomes and their contents promote cancer metastasis. Phosphoglycerate mutase 1 (PGAM1) is involved in various cancer-related processes. Nevertheless, the underlying mechanism of exosomal PGAM1 in prostate cancer (PCa) metastasis remains unclear. In this study, we performed in vitro and in vivo to determine the functions of exosomal PGAM1 in the angiogenesis of patients with metastatic PCa. We performed Glutathione-S-transferase pulldown, co-immunoprecipitation, western blotting and gelatin degradation assays to determine the pathway mediating the effect of exosomal PGAM1 in PCa. Our results revealed a significant increase in exosomal PGAM1 levels in the plasma of patients with metastatic PCa compared to patients with non-metastatic PCa. Furthermore, PGAM1 was a key factor initiating PCa cell metastasis by promoting invadopodia formation and could be conveyed by exosomes from PCa cells to human umbilical vein endothelial cells (HUVECs). In addition, exosomal PGAM1 could bind to γ-actin (ACTG1), which promotes podosome formation and neovascular sprouting in HUVECs. In vivo results revealed exosomal PGAM1 enhanced lung metastasis in nude mice injected with PCa cells via the tail vein. In summary, exosomal PGAM1 promotes angiogenesis and could be used as a liquid biopsy marker for PCa metastasis.
Topics: Animals; Humans; Male; Mice; Actins; Cell Line, Tumor; Cell Proliferation; Endothelial Cells; Exosomes; Mice, Nude; MicroRNAs; Neoplasm Metastasis; Phosphoglycerate Mutase; Prostatic Neoplasms
PubMed: 37542027
DOI: 10.1038/s41419-023-06007-4 -
Cell Reports Aug 2023Invadopodia are extracellular matrix (ECM) degrading structures, which promote cancer cell invasion. The nucleus is increasingly viewed as a mechanosensory organelle...
Invadopodia are extracellular matrix (ECM) degrading structures, which promote cancer cell invasion. The nucleus is increasingly viewed as a mechanosensory organelle that determines migratory strategies. However, how the nucleus crosstalks with invadopodia is little known. Here, we report that the oncogenic septin 9 isoform 1 (SEPT9_i1) is a component of breast cancer invadopodia. SEPT9_i1 depletion diminishes invadopodium formation and the clustering of the invadopodium precursor components TKS5 and cortactin. This phenotype is characterized by deformed nuclei and nuclear envelopes with folds and grooves. We show that SEPT9_i1 localizes to the nuclear envelope and juxtanuclear invadopodia. Moreover, exogenous lamin A rescues nuclear morphology and juxtanuclear TKS5 clusters. Importantly, SEPT9_i1 is required for the amplification of juxtanuclear invadopodia, which is induced by the epidermal growth factor. We posit that nuclei of low deformability favor the formation of juxtanuclear invadopodia in a SEPT9_i1-dependent manner, which functions as a tunable mechanism for overcoming ECM impenetrability.
Topics: Humans; Female; Septins; Podosomes; Protein Isoforms; Breast Neoplasms; Adaptor Proteins, Vesicular Transport; Cell Line, Tumor; Neoplasm Invasiveness
PubMed: 37516960
DOI: 10.1016/j.celrep.2023.112893 -
Cell Structure and Function Sep 2023Invadopodia are protrusive structures that mediate the extracellular matrix (ECM) degradation required for tumor invasion and metastasis. Rho small GTPases regulate...
Invadopodia are protrusive structures that mediate the extracellular matrix (ECM) degradation required for tumor invasion and metastasis. Rho small GTPases regulate invadopodia formation, but the molecular mechanisms of how Rho small GTPase activities are regulated at the invadopodia remain unclear. Here we have identified FilGAP, a GTPase-activating protein (GAP) for Rac1, as a negative regulator of invadopodia formation in tumor cells. Depletion of FilGAP in breast cancer cells increased ECM degradation and conversely, overexpression of FilGAP decreased it. FilGAP depletion promoted the formation of invadopodia with ECM degradation. In addition, FilGAP depletion and Rac1 overexpression increased the emergence of invadopodia induced by epidermal growth factor, whereas FilGAP overexpression suppressed it. Overexpression of GAP-deficient FilGAP mutant enhanced invadopodia emergence as well as FilGAP depletion. The pleckstrin-homology (PH) domain of FilGAP binds phosphatidylinositol 3,4-bisphosphate [PI(3,4)P], which is distributed on membranes of the invadopodia. FilGAP localized to invadopodia in breast cancer cells on the ECM, but FilGAP mutant lacking PI(3,4)P-binding showed low localization. Similarly, the decrease of PI(3,4)P production reduced the FilGAP localization. Our results suggest that FilGAP localizes to invadopodia through its PH domain binding to PI(3,4)P and down-regulates invadopodia formation by inactivating Rac1, inhibiting ECM degradation in invasive tumor cells.Key words: invadopodia, breast carcinoma, Rac1, FilGAP, PI(3,4)P.
Topics: Humans; Female; GTPase-Activating Proteins; Breast Neoplasms; Podosomes; rho GTP-Binding Proteins; Cell Line, Tumor; Extracellular Matrix
PubMed: 37482421
DOI: 10.1247/csf.23032