Carcinoma-associated fibroblasts (CAFs) are the main cellular components of the tumor microenvironment and promote cancer progression by modifying the extracellular matrix (ECM). The tumor-associated ECM is characterized by collagen crosslinking catalyzed by lysyl oxidase (LOX). Small extracellular vesicles (sEVs) mediate cell-cell communication. However, the interactions between sEVs and the ECM remain unclear. Here, we demonstrated that sEVs released from oral squamous cell carcinoma (OSCC)-derived CAFs induce collagen crosslinking, thereby promoting epithelial-mesenchymal transition (EMT). CAF sEVs preferably bound to the ECM rather than being taken up by fibroblasts and induced collagen crosslinking, and a LOX inhibitor or blocking antibody suppressed this effect. Active LOX (αLOX), but not the LOX precursor, was enriched in CAF sEVs and interacted with periostin, fibronectin, and bone morphogenetic protein-1 on the surface of sEVs. CAF sEV-associated integrin α2β1 mediated the binding of CAF sEVs to collagen I, and blocking integrin α2β1 inhibited collagen crosslinking by interfering with CAF sEV binding to collagen I. CAF sEV-induced collagen crosslinking promoted the EMT of OSCC through FAK/paxillin/YAP pathway. Taken together, these findings reveal a novel role of CAF sEVs in tumor ECM remodeling, suggesting a critical mechanism for CAF-induced EMT of cancer cells.
Humans ; Paxillin/metabolism* ; Protein-Lysine 6-Oxidase/metabolism* ; Carcinoma, Squamous Cell/pathology* ; Epithelial-Mesenchymal Transition ; Integrin alpha2beta1/metabolism* ; Mouth Neoplasms/pathology* ; Collagen/metabolism* ; Fibroblasts ; Extracellular Vesicles/metabolism* ; Cell Line, Tumor ; Tumor Microenvironment

Animals ; Arthritis, Experimental ; Collagen Type II ; Male ; Mice ; Mice, Inbred DBA ; Receptors, Adrenergic, alpha-1 ; Signal Transduction ; T-Lymphocytes, Regulatory/immunology*

Skeletal mineralization is initiated in matrix vesicles (MVs), the small extracellular vesicles derived from osteoblasts and chondrocytes. Calcium and inorganic phosphate (Pi) taken up by MVs form hydroxyapatite crystals, which propagate on collagen fibrils to mineralize the extracellular matrix. Insufficient calcium or phosphate impairs skeletal mineralization. Because active vitamin D is necessary for intestinal calcium absorption, vitamin D deficiency is a significant cause of rickets/osteomalacia. Chronic hypophosphatemia also results in rickets/osteomalacia. Excessive action of fibroblast growth factor 23 (FGF23), a key regulator of Pi metabolism, leads to renal Pi wasting and impairs vitamin D activation. X-linked hypophosphatemic rickets (XLH) is the most common form of hereditary FGF23-related hypophosphatemia, and enhanced FGF receptor (FGFR) signaling in osteocytes may be involved in the pathogenesis of this disease. Increased extracellular Pi triggers signal transduction via FGFR to regulate gene expression, implying a close relationship between Pi metabolism and FGFR. An anti-FGF23 antibody, burosumab, has recently been developed as a new treatment for XLH. In addition to various forms of rickets/osteomalacia, hypophosphatasia (HPP) is characterized by impaired skeletal mineralization. HPP is caused by inactivating mutations in tissue-nonspecific alkaline phosphatase, an enzyme rich in MVs. The recent development of enzyme replacement therapy using bone-targeting recombinant alkaline phosphatase has improved the prognosis, motor function, and quality of life in patients with HPP. This links impaired skeletal mineralization with various conditions, and unraveling its pathogenesis will lead to more precise diagnoses and effective treatments.
Absorption ; Alkaline Phosphatase ; Calcium ; Chondrocytes ; Collagen ; Diagnosis ; Durapatite ; Enzyme Replacement Therapy ; Extracellular Matrix ; Extracellular Vesicles ; Familial Hypophosphatemic Rickets ; Fibroblast Growth Factors ; Gene Expression ; Humans ; Hypophosphatasia ; Hypophosphatemia ; Metabolism ; Miners ; Osteoblasts ; Osteocytes ; Prognosis ; Quality of Life ; Receptors, Fibroblast Growth Factor ; Rickets ; Signal Transduction ; Vitamin D ; Vitamin D Deficiency

BACKGROUND/AIMS: Although epigallocatechin-3-gallate (EGCG), which is found in high contents in the dried leaves of green tea, has been reported to have an anti-platelet effect, synergistic effects of EGCG in addition to current anti-platelet medications remains to be elucidated. METHODS: Blood samples were obtained from 40 participants who took aspirin (ASA, n = 10), clopidogrel (CPD, n = 10), ticagrelor (TCG, n = 10) and no anti-platelet medication (Control, n = 10). Ex vivo platelet aggregation and adhesion under various stimulators were analyzed by multiple electrode aggregometry (MEA) and Impact-R systems. PAC-1 and P-selectin expressions in human platelets were analyzed by flow cytometry. RESULTS: In MEA analysis, adenosine diphosphate (ADP) and thrombin receptor activating peptide (TRAP)-induced platelet aggregations were lower in the CPD and the TCG groups; arachidonic acid (AA)-induced platelet aggregation was lower in the ASA group, whereas collagen (COL)-induced platelet aggregations were comparable among four groups. EGCG significantly reduced ADP- and COL-induced platelet aggregation in dose-dependent manner (ADP, p = 0.04; COL, p < 0.01). There were no additional suppressions of platelet aggregation stimulated by AA in the ASA group, and by ADP in the CPD and TCG groups. Moreover, EGCG suppressed shear stress-induced platelet adhesion on Impact-R, and had no effect on P-selectin and PAC-1 expressions. CONCLUSIONS: Ex vivo treatment of EGCG inhibited platelet adhesion and aggregation without changes in P-selectin and PAC-1 expression. There was no additional suppressions in platelet aggregation stimulated by AA in the ASA group and ADP in the CPD and TCG groups.
Adenosine Diphosphate ; Arachidonic Acid ; Aspirin* ; Blood Platelets ; Catechin ; Collagen ; Electrodes ; Flow Cytometry ; Humans ; P-Selectin ; Platelet Aggregation ; Platelet Aggregation Inhibitors ; Receptors, Thrombin ; Tea

The tumor microenvironment greatly influences cancer cell characteristics, and acidic extracellular pH has been implicated as an essential factor in tumor malignancy and the induction of drug resistance. Here, we examined the characteristics of gastric carcinoma (GC) cells under conditions of extracellular acidity and attempted to identify a means of enhancing treatment efficacy. Acidic conditions caused several changes in GC cells adversely affecting chemotherapeutic treatment. Extracellular acidity did inhibit GC cell growth by inducing cell cycle arrest, but did not induce cell death at pH values down to 6.2, which was consistent with down-regulated cyclin D1 and up-regulated p21 mRNA expression. Additionally, an acidic environment altered the expression of atg5, HSPA1B, collagen XIII, collagen XXAI, slug, snail, and zeb1 genes which are related to regulation of cell resistance to cytotoxicity and malignancy, and as expected, resulted in increased resistance of cells to multiple chemotherapeutic drugs including etoposide, doxorubicin, daunorubicin, cisplatin, oxaliplatin and 5-FU. Interestingly, however, acidic environment dramatically sensitized GC cells to apoptosis induced by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). Consistently, the acidity at pH 6.5 increased mRNA levels of DR4 and DR5 genes, and also elevated protein expression of both death receptors as detected by immunoblotting. Gene silencing analysis showed that of these two receptors, the major role in this effect was played by DR5. Therefore, these results suggest that extracellular acidity can sensitize TRAIL-mediated apoptosis at least partially via DR5 in GCs while it confers resistance to various type of chemotherapeutic drugs.
Apoptosis* ; Cell Cycle Checkpoints ; Cell Death ; Cisplatin ; Collagen ; Cyclin D1 ; Daunorubicin ; Doxorubicin ; Drug Resistance ; Etoposide ; Fluorouracil ; Gastropoda ; Gene Silencing ; Hydrogen-Ion Concentration ; Immunoblotting ; Necrosis* ; Receptors, Death Domain ; RNA, Messenger ; Snails ; Stomach Neoplasms* ; Treatment Outcome ; Tumor Microenvironment

PURPOSE: The purpose of this study was to evaluate the effects of 1,25-dihydroxyvitamin D₃ on the proliferation, differentiation, and matrix mineralization of MC3T3-E1 osteoblast-like cells in vitro. METHODS: MC3T3-E1 osteoblastic cells and 1,25-dihydroxyvitamin D₃ were prepared. Cytotoxic effects and osteogenic differentiation were evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, alkaline phosphatase (ALP) activity assay, ALP staining, alizarin red S staining, and reverse transcription-polymerase chain reaction (RT-PCR) for osteogenic differentiation markers such as ALP, collagen type I (Col-I), osteocalcin (OCN), vitamin D receptor (VDR), and glyceraldehyde 3-phosphate dehydrogenase. RESULTS: The MTT assay showed that 1,25-dihydroxyvitamin D₃ did not inhibit cell growth and that the rate of cell proliferation was higher than in the positive control group at all concentrations. ALP activity was also higher than in the positive control group at low concentrations of 1,25-dihydroxyvitamin D₃ (10−10, 10−12, and 10−14 M). RT-PCR showed that the gene expression levels of ALP, Col-I, OCN, and vitamin D receptor (VDR) were higher at a low concentration of 1,25-dihydroxyvitamin D₃ (10−12 M). Alizarin red S staining after treatment with 1,25-dihydroxyvitamin D₃ (10−12 M) showed no significant differences in the overall degree of calcification. In contrast to the positive control group, formation of bone nodules was induced in the early stages of cell differentiation. CONCLUSIONS: We suggest that 1,25-dihydroxyvitamin D₃ positively affects cell differentiation and matrix mineralization. Therefore, it may function as a stimulating factor in osteoblastic bone formation and can be used as an additive in bone regeneration treatment.
Alkaline Phosphatase ; Antigens, Differentiation ; Bone Regeneration ; Calcitriol ; Cell Differentiation ; Cell Proliferation ; Collagen Type I ; Gene Expression ; Glyceraldehyde 3-Phosphate ; In Vitro Techniques ; Miners ; Osteoblasts ; Osteocalcin ; Osteogenesis ; Oxidoreductases ; Receptors, Calcitriol

The present study was designed to elucidate whether the mechanism by which osthole decreases collagenI/III contents and their ratio is regulating the TGF-β/Smad signaling pathway in TGF-β1-overexpressed mouse cardiac fibroblasts (CFs). These CFs were cultured and treated with different concentrations of osthole. Our results showed that the TGF-β1 expression in the CFs transfected with that the recombinant expression plasmids pcDNA3.1(+)-TGF-β1 was significantly enhanced. After the CFs were treated with 1.25-5 μg·mL of osthole for 24 h, the mRNA and protein expression levels of collagensIand III were reduced. The collagen I/III ratio was also reduced. The mRNA and protein expression levels of TGF-β1, TβRI, Smad2/3, P-Smad2/3, Smad4, and α-SMA were decreased, whereas the expression level of Smad7 was increased. These effects suggested that osthole could inhibit collagen I and III expression and reduce their ratio via the TGF-β/Smad signaling pathway in TGF-β1 overexpressed CFs. These effects of osthole may play beneficial roles in the prevention and treatment of myocardial fibrosis.
Actins ; genetics ; Animals ; Cells, Cultured ; Collagen ; biosynthesis ; genetics ; Coumarins ; pharmacology ; Fibroblasts ; drug effects ; metabolism ; Gene Expression Regulation ; drug effects ; Mice ; Myocardium ; cytology ; Protein-Serine-Threonine Kinases ; genetics ; RNA, Messenger ; genetics ; Real-Time Polymerase Chain Reaction ; Receptor, Transforming Growth Factor-beta Type I ; Receptors, Transforming Growth Factor beta ; genetics ; Signal Transduction ; drug effects ; Smad Proteins ; genetics ; Transforming Growth Factor beta1 ; genetics

OBJECTIVETo study the effect of total flavonoids of Astmgali Radix (TFA) on liver cirrhosis induced with dimethylnitrosamine (DMN) in rats, and the effect on peroxisome proliferator-activated receptor γ (PPARγ), uncoupling protein 2 (UCP2) and farnesoid X receptor (FXR).

METHODSFifty-three Sprague-Dawley rats were randomly divided into a control group (10 rats) and a DMN group (43 rats). Rats in the DMN group were given DMN for 4 weeks and divided randomly into a model group (14 rats), a low-dosage TFA group (14 rats) and a high-dosage TFA group (15 rats) in the 3rd week. Rats were given TFA for 4 weeks at the dosage of 15 and 30 mg/kg in the low- and high-TFA groups, respectively. At the end of the experiment blood and liver samples were collected. Serum liver function and liver tissue hydroxyproline content were determined. hematoxylin-eosin (HE), Sirus red and immunohistochemical stainings of collagen I, smooth muscle actin (α-SMA) was conducted in paraffinembedded liver tissue slices. Real time polymerase chain reaction (PCR) was adopted to determine PPARγ, UCP2 and FXR mRNA levels. Western blot was adopted to determine protein levels of collagen I, α-SMA, PPARγ, UCP2 and FXR.

RESULTSCompared with the model group, TFA increased the ratio of liver/body weight (low-TFA group P<0.05, high-TFA group P<0.01), improved liver biochemical indices (P<0.01 for ALT, AST, GGT in both groups, P<0.05 for albumin and TBil in the high-TFA group) and reduced liver tissue hydroxproline content (P<0.01 in both groups) in treatment groups significantly. HE staining showed that TFA alleviated liver pathological changes markedly and Sirus red staining showed that TFA reduced collagen deposition, alleviated formation and extent of liver pseudolobule. Collagen I and α-SMA immunohistochemical staining showed that staining area and extent markedly decreased in TFA groups compared with the model group. TFA could increase PPARγ, it regulated target UCP2, and FXR levels significantly compared with the model group (in the low-TFA group all P<0.05, in the high group all P<0.01).

CONCLUSIONTFA could improve liver function, alleviate liver pathological changes, and reduce collagen deposition and formation of liver pseudolobule in rats with liver cirrhosis. The antifibrotic effect of TFA was through regulating PPARγ signal pathway and the interaction with FXR.

Actins ; metabolism ; Animals ; Blotting, Western ; Body Weight ; drug effects ; Collagen Type I ; metabolism ; Dimethylnitrosamine ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Flavonoids ; pharmacology ; therapeutic use ; Hydroxyproline ; metabolism ; Liver ; drug effects ; pathology ; Liver Cirrhosis ; blood ; drug therapy ; genetics ; pathology ; Male ; Organ Size ; drug effects ; PPAR gamma ; genetics ; metabolism ; Plant Extracts ; pharmacology ; therapeutic use ; RNA, Messenger ; genetics ; metabolism ; Rats, Sprague-Dawley ; Real-Time Polymerase Chain Reaction ; Receptors, Cytoplasmic and Nuclear ; genetics ; metabolism ; Uncoupling Protein 2 ; genetics ; metabolism

Drug-induced gingival overgrowth (DIGO) is characterized by fibrous gingival hyperplasia and increased gingival volume. DIGO is histologically associated with proliferation of cells and deposition of extracellular matrices, particularly collagen. Integrin α2β1 is related to collagen phagocytosis and involved in the occurrence and progression of DIGO. This paper reviews the progress of research on the relationship between integrin α2β1 and DIGO.
Collagen ; Gingiva ; Gingival Overgrowth ; Humans ; Integrin alpha2beta1 ; Phagocytosis

BACKGROUND/AIMS: Inhaled corticosteroids are the most effective treatment currently available for asthma, but their beneficial effect against airway remodeling is limited. The tyrosine kinase inhibitor nilotinib has inhibitory activity against c-kit and the platelet-derived growth factor receptor. We compared the effects of fluticasone and nilotinib on airway remodeling in a chronic asthma model. We also examined whether co-treatment with nilotinib and fluticasone had any synergistic effect in preventing airway remodeling. METHODS: We developed a mouse model of airway remodeling, including smooth muscle thickening, in which ovalbumin (OVA)-sensitized female BALB/c-mice were repeatedly exposed to intranasal OVA administration twice per week for 3 months. Mice were treated with fluticasone and/or nilotinib intranasally during the OVA challenge. RESULTS: Mice chronically exposed to OVA developed eosinophilic airway inflammation and showed features of airway remodeling, including thickening of the peribronchial smooth muscle layer. Both fluticasone and nilotinib attenuated airway smooth muscle thickening. However, only nilotinib suppressed fibrotic changes, demonstrating inhibition of collagen deposition. Fluticasone reduced pro-inflammatory cells, such as eosinophils, and several cytokines, such as interleukin 4 (IL-4), IL-5, and IL-13, induced by repeated OVA challenges. On the other hand, nilotinib reduced transforming growth factor β1 levels in bronchoalveolar lavage fluid and inhibited fibroblast proliferation significantly. CONCLUSIONS: These results suggest that fluticasone and nilotinib suppressed airway remodeling in this chronic asthma model through anti-inflammatory and anti-fibrotic pathways, respectively.
Adrenal Cortex Hormones ; Airway Remodeling ; Animals ; Asthma* ; Bronchoalveolar Lavage Fluid ; Collagen ; Cytokines ; Eosinophils ; Female ; Fibroblasts ; Fluticasone* ; Hand ; Humans ; Inflammation ; Interleukin-13 ; Interleukin-4 ; Interleukin-5 ; Mice ; Muscle, Smooth ; Ovalbumin ; Ovum ; Protein-Tyrosine Kinases ; Receptors, Platelet-Derived Growth Factor ; Transforming Growth Factors