Β1 Integrin Research Articles

Influence of the Surface Topography of Titanium Dental Implants on the Behavior of Human Amniotic Stem Cells.

The dental implant surface plays a crucial role in osseointegration. The topography and physicochemical properties will affect the cellular functions. In this research, four distinct titanium surfaces have been studied: machined acting (MACH), acid etched (AE), grit blasting (GBLAST), and a combination of grit blasting and subsequent acid etching (GBLAST + AE). Human amniotic mesenchymal (hAMSCs) and epithelial stem cells (hAECs) isolated from the amniotic membrane have attractive stem-cell properties. They were cultured on titanium surfaces to analyze their impact on biological behavior. The surface roughness, microhardness, wettability, and surface energy were analyzed using interferometric microscopy, Vickers indentation, and drop-sessile techniques. The GBLAST and GBLAST + AE surfaces showed higher roughness, reduced hydrophilicity, and lower surface energy with significant differences. Increased microhardness values for GBLAST and GBLAST + AE implants were attributed to surface compression. Cell viability was higher for hAMSCs, particularly on GBLAST and GBLAST + AE surfaces. Alkaline phosphatase activity enhanced in hAMSCs cultured on GBLAST and GBLAST + AE surfaces, while hAECs showed no mineralization signals. Osteogenic gene expression was upregulated in hAMSCs on GBLAST surfaces. Moreover, α2 and β1 integrin expression enhanced in hAMSCs, suggesting a surface-integrin interaction. Consequently, hAMSCs would tend toward osteoblastic differentiation on grit-blasted surfaces conducive to osseointegration, a phenomenon not observed in hAECs.

Role of TSP-1 and its receptor ITGB3 in the renal tubulointerstitial injury of focal segmental glomerulosclerosis

Focal segmental glomerulosclerosis (FSGS), a common cause of primary glomerulonephritis, has a poor prognosis and is pathologically featured by tubulointerstitial injury. Thrombospondin-1 (TSP-1) is an extracellular matrix protein that acts in combination with different receptors in the kidney. Here, we analyzed the tubular expression of TSP-1 and its receptor integrin β3 (ITGB3) in FSGS. Previously the renal interstitial chip analysis of FSGS patients with tubular interstitial injury showed that the expressions of TSP-1 and ITGB3 were up-regulated. We found that the level of TSP-1 and ITGB3 increased in the tubular cells of FSGS patients. The serum level of TSP-1 increased and was correlated to the degree of tubulointerstitial lesions in FSGS patients. THBS1/ITGB3 signaling induced renal tubular injury in HK-2 cells exposure to BSA and the ADR-induced nephropathy model. THBS1 knockout ameliorated tubular injury and renal fibrosis in ADR-treated mice. THBS1 knockdown decreased the expression of KIM-1 and caspase 3 in the HK-2 cells treated with BSA, while THBS1 overexpression could induce tubular injury. In vivo, we identified cyclo-RGDfK as an agent to block the binding of TSP-1 to ITGB3. Cyclo-RGDfK treatment could alleviate ADR-induced renal tubular injury and interstitial fibrosis in mice. Moreover, TSP-1 and ITGB3 were colocalized in tubular cells of FSGS patients and ADR-treated mice. Taken together, our data showed that TSP-1/ITGB3 signaling contributed to the development of renal tubulointerstitial injury in FSGS, potentially identifying a new therapeutic target for FSGS.

It is time to reconsider antibodies against integrin β4 in mucous membrane pemphigoid: Comment on ‘Native collagen XVII complex ELISA: An approach for diagnosis and monitoring of anti‐integrin β4 mucous membrane pemphigoid’

It is time to reconsider antibodies against integrin β4 in mucous membrane pemphigoid: Comment on ‘Native collagen <scp>XVII</scp> complex <scp>ELISA</scp>: An approach for diagnosis and monitoring of anti‐integrin β4 mucous membrane pemphigoid’

Netrin-1 Is an Important Mediator in Microglia Migration.

Microglia migrate to the cerebral cortex during early embryonic stages. However, the precise mechanisms underlying microglia migration remain incompletely understood. As an extracellular matrix protein, Netrin-1 is involved in modulating the motility of diverse cells. In this paper, we found that Netrin-1 promoted microglial BV2 cell migration in vitro. Mechanism studies indicated that the activation of GSK3β activity contributed to Netrin-1-mediated microglia migration. Furthermore, Integrin α6/β1 might be the relevant receptor. Single-cell data analysis revealed the higher expression of Integrin α6 subunit and β1 subunit in microglia in comparison with classical receptors, including Dcc, Neo1, Unc5a, Unc5b, Unc5c, Unc5d, and Dscam. Microscale thermophoresis (MST) measurement confirmed the high binding affinity between Integrin α6/β1 and Netrin-1. Importantly, activation of Integrin α6/β1 with IKVAV peptides mirrored the microglia migration and GSK3 activation induced by Netrin-1. Finally, conditional knockout (CKO) of Netrin-1 in radial glial cells and their progeny led to a reduction in microglia population in the cerebral cortex at early developmental stages. Together, our findings highlight the role of Netrin-1 in microglia migration and underscore its therapeutic potential in microglia-related brain diseases.

The Role of Vimentin in Human Corneal Fibroblast Spreading and Myofibroblast Transformation.

Vimentin has been reported to play diverse roles in cell processes such as spreading, migration, cell-matrix adhesion, and fibrotic transformation. Here, we assess how vimentin impacts cell spreading, morphology, and myofibroblast transformation of human corneal fibroblasts. Overall, although knockout (KO) of vimentin did not dramatically impact corneal fibroblast spreading and mechanical activity (traction force), cell elongation in response to PDGF was reduced in vimentin KO cells as compared to controls. Blocking vimentin polymerization using Withaferin had even more pronounced effects on cell spreading and also inhibited cell-induced matrix contraction. Furthermore, although absence of vimentin did not completely block TGFβ-induced myofibroblast transformation, the degree of transformation and amount of αSMA protein expression was reduced. Proteomics showed that vimentin KO cells cultured in TGFβ had a similar pattern of protein expression as controls. One exception included periostin, an ECM protein associated with wound healing and fibrosis in other cell types, which was highly expressed only in Vim KO cells. We also demonstrate for the first time that LRRC15, a protein previously associated with myofibroblast transformation of cancer-associated fibroblasts, is also expressed by corneal myofibroblasts. Interestingly, proteins associated with LRRC15 in other cell types, such as collagen, fibronectin, β1 integrin and α11 integrin, were also upregulated. Overall, our data show that vimentin impacts both corneal fibroblast spreading and myofibroblast transformation. We also identified novel proteins that may regulate corneal myofibroblast transformation in the presence and/or absence of vimentin.

Vimentin-mediated buffering of internal integrin β1 pool increases survival of cells from anoikis

BackgroundThe intermediate filament protein vimentin is widely recognized as a molecular marker of epithelial-to-mesenchymal transition. Although vimentin expression is strongly associated with cancer metastatic potential, the exact role of vimentin in cancer metastasis and the underlying mechanism of its pro-metastatic functions remain unclear.ResultsThis study revealed that vimentin can enhance integrin β1 surface expression and induce integrin-dependent clustering of cells, shielding them against anoikis cell death. The increased integrin β1 surface expression in suspended cells was caused by vimentin-mediated protection of the internal integrin β1 pool against lysosomal degradation. Additionally, cell detachment was found to induce vimentin Ser38 phosphorylation, allowing the translocation of internal integrin β1 to the plasma membrane. Furthermore, the use of an inhibitor of p21-activated kinase PAK1, one of the kinases responsible for vimentin Ser38 phosphorylation, significantly reduced cancer metastasis in animal models.ConclusionsThese findings suggest that vimentin can act as an integrin buffer, storing internalized integrin β1 and releasing it when needed. Overall, this study provides insights regarding the strong correlation between vimentin expression and cancer metastasis and a basis for blocking metastasis using this novel therapeutic mechanism.

Prostaglandin F2 Receptor Negative Regulator (PTGFRN) Expression Correlates With a Metastatic-like Phenotype in Epidermoid Carcinoma, Pediatric Medulloblastoma, and Mesothelioma.

Prostaglandin F2 receptor negative regulator (PTGFRN) is a transmembrane protein associated with metastatic characteristics of certain cancer types. However, it remains poorly characterized and its direct function in cancer remains unclear. The study presented here aims to further examine whether PTGFRN expression affects a cancer cell's phenotype, as well as metastatic-like characteristics. We used stable shRNA and cDNA transfections to respectively knockdown and overexpress PTGFRN in three different cancer cell lines, two of which are representative of rare and aggressive cancers (Mesothelioma and Pediatric Medulloblastoma). We then examined the characteristics of the resulting clones and showed a decrease in proliferation, migration, colony formation, and spheroid growth capabilities in cells where PTGFRN expression had been inhibited, while cells overexpressing PTGFRN showed the opposite. In addition, we showed that PTGFRN displayed direct binding to two protein partners, Integrin β1 and E. Cadherin, the latter of which is a novel direct binding partner to PTGFRN. Furthermore, silencing PTGFRN expression impacted the cellular process of autophagy, thereby providing another avenue by which PTGFRN potentially contributes to a cancer cell phenotype. Our findings demonstrate the potential role of PTGFRN in cancer metastasis and suggest PTGFRN as a future target for drug development in the treatment of metastatic cancers.

Integrin β3 Reprogramming Stemness in HER2-Positive Breast Cancer Cell Lines.

HER2-positive breast cancer, characterised by overexpressed HER2 levels, is associated with aggressive tumour behaviour and poor prognosis. Trastuzumab is a standard treatment; however, approximately 50% of patients develop resistance within one year. This study investigates the role of ITGβ3 in promoting stemness and resistance in HER2-positive breast cancer cell lines (HCC1954 and SKBR3). The findings demonstrate that chronic exposure to trastuzumab upregulates stem cell markers (SOX2, OCT4, KLF4, NANOG, SALL4, ALDH, BMI1, Nestin, Musashi 1, TIM3, CXCR4). Given the documented role of RGD-binding integrins in drug resistance and stemness, we specifically investigated their impact on resistant cells. Overexpression of ITGβ3 enhances the expression of these stem cell markers, while silencing ITGβ3 reduces their expression, suggesting a major role for ITGβ3 in maintaining stemness and resistance. Further analysis reveals that ITGβ3 activates the Notch signalling pathway, known for regulating stem cell maintenance. The combination of trastuzumab and cilengitide, an integrin inhibitor, significantly decreases the expression of stem cell markers in resistant cells, indicating a potential therapeutic strategy to overcome resistance. These results identify the importance of ITGβ3 in mediating stemness and trastuzumab resistance through Notch signalling in HER2-positive breast cancer, offering new approaches for enhancing treatment efficacy.

GPR126 is a specifier of blood-brain barrier formation in the mouse central nervous system.

The blood-brain barrier (BBB) acquires unique properties to regulate neuronal function during development. The formation of the BBB, which occurs in tandem with angiogenesis, is directed by the Wnt/β-catenin signaling pathway. Yet the exact molecular interplay remains elusive. Our study reveals the G protein-coupled receptor GPR126 as a critical target of canonical Wnt signaling, essential for the development of the BBB's distinctive vascular characteristics and its functional integrity. Endothelial cell-specific deletion of the Gpr126 gene in mice induced aberrant vascular morphogenesis, resulting in disrupted BBB organization. Simultaneously, heightened transcytosis in vitro compromised barrier integrity, resulting in enhanced vascular permeability. Mechanistically, GPR126 enhanced endothelial cell migration, pivotal for angiogenesis, acting through an interaction between LRP1 and β1 integrin, thereby balancing the levels of β1 integrin activation and recycling. Overall, we identified GPR126 as a specifier of an organotypic vascular structure, which sustained angiogenesis and guaranteed the acquisition of the BBB properties during development.

WISP-1 Regulates Cardiac Fibrosis by Promoting Cardiac Fibroblasts' Activation and Collagen Processing.

Hypertension induces cardiac fibrotic remodelling characterised by the phenotypic switching of cardiac fibroblasts (CFs) and collagen deposition. We tested the hypothesis that Wnt1-inducible signalling pathway protein-1 (WISP-1) promotes CFs' phenotypic switch, type I collagen synthesis, and in vivo fibrotic remodelling. The treatment of human CFs (HCFs, n = 16) with WISP-1 (500 ng/mL) induced a phenotypic switch (α-smooth muscle actin-positive) and type I procollagen cleavage to an intermediate form of collagen (pC-collagen) in conditioned media after 24h, facilitating collagen maturation. WISP-1-induced collagen processing was mediated by Akt phosphorylation via integrin β1, and disintegrin and metalloproteinase with thrombospondin motifs 2 (ADAMTS-2). WISP-1 wild-type (WISP-1+/+) mice and WISP-1 knockout (WISP-1-/-) mice (n = 5-7) were subcutaneously infused with angiotensin II (AngII, 1000 ng/kg/min) for 28 days. Immunohistochemistry revealed the deletion of WISP-1 attenuated type I collagen deposition in the coronary artery perivascular area compared to WISP-1+/+ mice after a 28-day AngII infusion, and therefore, the deletion of WISP-1 attenuated AngII-induced cardiac fibrosis in vivo. Collectively, our findings demonstrated WISP-1 is a critical mediator in cardiac fibrotic remodelling, by promoting CFs' activation via the integrin β1-Akt signalling pathway, and induced collagen processing and maturation via ADAMTS-2. Thereby, the modulation of WISP-1 levels could provide potential therapeutic targets in clinical treatment.

Blocking Oncostatin M receptor abrogates STAT3 mediated integrin signaling and overcomes chemoresistance in ovarian cancer

Chemotherapy such as cisplatin is widely used to treat ovarian cancer either before or after surgical debulking. However, cancer relapse due to chemotherapy resistance is a major challenge in the treatment of ovarian cancer. The underlying mechanisms related to chemotherapy resistance remain largely unclear. Therefore, identification of effective therapeutic strategies is urgently needed to overcome therapy resistance. Transcriptome-based analysis, in vitro studies and functional assays identified that cisplatin-resistant ovarian cancer cells express high levels of OSMR compared to cisplatin sensitive cells. Furthermore, OSMR expression associated with a module of integrin family genes and predominantly linked with integrin αV (ITGAV) and integrin β3 (ITGB3) for cisplatin resistance. Using ectopic expression and knockdown approaches, we proved that OSMR directly regulates ITGAV and ITGB3 gene expression through STAT3 activation. Notably, targeting OSMR using anti-OSMR human antibody inhibited the growth and metastasis of ovarian cancer cells and sensitized cisplatin treatment. Taken together, our results underscore the pivotal role of OSMR as a requirement for cisplatin resistance in ovarian cancer. Notably, OSMR fostered the expression of a distinct set of integrin genes, which in turn resulted into a crosstalk between OSMR and integrins for signaling activation that is critical for cisplatin resistance. Therefore, targeting OSMR emerges as a promising and viable strategy to reverse cisplatin-resistance in ovarian cancer.

A synthetic bioactive peptide of the C-terminal fragment of adhesion protein Fibulin7 attenuates the inflammatory functions of innate immune cells in LPS-induced systemic inflammation.

Systemic inflammation is associated with improper localization of hyperactive neutrophils and monocytes in visceral organs. Previously, a C-terminal fragment of adhesion protein Fibulin7 (Fbln7-C) was shown to regulate innate immune functionality during inflammation. Recently, a shorter bioactive peptide of Fbln7-C, FC-10, via integrin binding was shown to reduce ocular angiogenesis. However, the role of FC-10 in regulating the neutrophils and monocyte functionality during systemic inflammatory conditions is unknown. The study sought to explore the role of FC-10 peptide on the functionality of innate immune cells during inflammation and endotoxemic mice. Neutrophils and monocytes were isolated from healthy donors and septic patient clinical samples and Cell adhesion assay was performed using a UV spectrophotometer. Gene expression studies were performed using qPCR. Protein level expression was measured using ELISA and flow cytometry. ROS assay, and activation markers analysis in vitro, and in vivo were done using flow cytometry. Cells were stimulated with LPS (100ng/mL) and studied in the presence of peptides (10μg, and 20μg/mL) in vitro. In an in vivo study, mice were administered with LPS (36.8mg/kg bw) and peptide (20μg). This study demonstrates that human neutrophils and monocytes adhere to FC-10 via integrin β1, inhibit spreading, ROS, surface activation markers (CD44, CD69), phosphorylated Src kinase, pro-inflammatory genes, and protein expression, compared to scrambled peptide in cells isolated from healthy donors and clinical sample. In line with the in vitro data, FC-10 (20μg) administration significantly decreases innate cell infiltration at inflammatory sites, improves survival in endotoxemia animals & reduces the inflammatory properties of neutrophils and monocytes isolated from septic patients. FC-10 peptide can regulate neutrophils and monocyte functions and has potential to be used as an immunomodulatory therapeutic in inflammatory diseases.

Calpain Small Subunit Mediated Secretion of Galectin-3 Regulates Traction Stress.

The complex regulation of traction forces (TF) produced during cellular migration remains poorly understood. We have previously found that calpain 4 (Capn4), the small non-catalytic subunit of the calpain 1 and 2 proteases, regulates the production of TF independent of the proteolytic activity of the larger subunits. Capn4 was later found to facilitate tyrosine phosphorylation and secretion of the lectin-binding protein galectin-3 (Gal3). In this study, recombinant Gal3 (rGal3) was added to the media-enhanced TF generated by capn4-/- mouse embryonic fibroblasts (MEFs). Extracellular Gal3 also rescued defects in the distribution, morphology, and adhesive strength of focal adhesions present in capn4-/- MEF cells. Surprisingly, extracellular Gal3 does not influence mechanosensing. c-Abl kinase was found to affect Gal3 secretion and the production of TF through phosphorylation of Y107 on Gal3. Our study also suggests that Gal3-mediated regulation of TF occurs through signaling pathways triggered by β1 integrin but not by focal adhesion kinase (FAK) Y397 autophosphorylation. Our findings provide insights into the signaling mechanism by which Capn4 and secreted Gal3 regulate cell migration through the modulation of TF distinctly independent from a mechanosensing mechanism.

The Balance between Protealysin and Its Substrate, the Outer Membrane Protein OmpX, Regulates Serratia proteamaculans Invasion.

Serratia are opportunistic bacteria, causing infections in plants, insects, animals and humans under certain conditions. The development of bacterial infection in the human body involves several stages of host-pathogen interaction, including entry into non-phagocytic cells to evade host immune cells. The facultative pathogen Serratia proteamaculans is capable of penetrating eukaryotic cells. These bacteria synthesize an actin-specific metalloprotease named protealysin. After transformation with a plasmid carrying the protealysin gene, noninvasive E. coli penetrate eukaryotic cells. This suggests that protealysin may play a key role in S. proteamaculans invasion. This review addresses the mechanisms underlying protealysin's involvement in bacterial invasion, highlighting the main findings as follows. Protealysin can be delivered into the eukaryotic cell by the type VI secretion system and/or by bacterial outer membrane vesicles. By cleaving actin in the host cell, protealysin can mediate the reversible actin rearrangements required for bacterial invasion. However, inactivation of the protealysin gene leads to an increase, rather than decrease, in the intensity of S. proteamaculans invasion. This indicates the presence of virulence factors among bacterial protealysin substrates. Indeed, protealysin cleaves the virulence factors, including the bacterial surface protein OmpX. OmpX increases the expression of the EGFR and β1 integrin, which are involved in S. proteamaculans invasion. It has been shown that an increase in the invasion of genetically modified S. proteamaculans may be the result of the accumulation of full-length OmpX on the bacterial surface, which is not cleaved by protealysin. Thus, the intensity of the S. proteamaculans invasion is determined by the balance between the active protealysin and its substrate OmpX.

Modified Hongteng Baijiang decoction enema improves sequelae of pelvic inflammatory disease by regulating the LIF/JAK2/STAT3 pathway and gut microbiota.

The sequelae of pelvic inflammatory disease (SPID) are major causes of secondary infertility. Modified Hongteng Baijiang decoction (MHTBD) has produced positive results in the treatment of patients with chronic pelvic inflammatory disease; however, its role in SPID remains elusive. Therefore, this study clarified the role of MHTBD in SPID pathogenesis. The main components in MHTBD were analyzed by using liquid chromatography‒mass spectrometry (LC/MS). An SPID rat model was established, and the rats were treated with different doses of MHTBD (0.504 g of raw drug/kg, 1.008 g of raw drug/kg, and 2.016 g of raw drug/kg). Endometrial pinopodes were observed via scanning electron microscopy, endometrial thickness and inflammatory cell infiltration were assessed via HE staining, and the expression of estrogen receptor (ER), progesterone receptor (PR), integrin β3 (ITGB3), and CD31 in the endometrium was detected by using immunohistochemistry. Western blot analysis was used to detect the protein expression of LIF, JAK2, p-JAK2, STAT3, and p-STAT3 in the endometrium. Moreover, the changes in the gut microbiota were analyzed via 16S rRNA sequencing. MHTBD improved endometrial receptivity, attenuated endometrial pathologic damage, reduced inflammatory cell infiltration, decreased ER and PR expression in the endometrium, and promoted the expression of LIF, p-JAK2, and p-STAT3 in the endometrium (p < .05) in SPID rats. Additionally, MHTBD treatment affected the composition of the gut microbiota in SPID rats. Furthermore, MHTBD attenuated endometrial receptivity and pathological damage in SPID rats by promoting the LIF/JAK2/STAT3 pathway. MHTBD attenuates SPID in rats by promoting the LIF/JAK2/STAT3 pathway and improving the composition of the gut microbiota. MHTBD may be a valuable drug for SPID therapy.

The effect of folic acid supplementation and folate deficiency on embryo implantation

Implantation is a critical stage of pregnancy, which occurs in a short period of interaction between the receptive endometrium and the embryo. Folic acid (FA) is a synthetic derivative of folate and is recommended as a pre-conceptional supplement. However, the impact of different doses of FA supplementation and folate deficiency during the early stages of pregnancy requires further investigation. The aim of this study was to investigate the possible effects of FA supplementation and folate deficiency on expression of Estrogen Receptor Alpha (ER-α), Vascular Endothelial Growth Factor-A (VEGFA), and Integrin alpha V and beta3 (Integrin αVβ3). A total of 32, 6–8-week old Wistar albino rats were divided into four groups of control, folate-deficiency, low-dose, and high-dose FA supplement groups. After five weeks of FA supplementation and folate deficiency model formation, mated rats were sacrificed on the 5th gestational day (GD), and implantation sites were collected. The expression of ER- α, VEGFA, and Integrin αVβ3 in the implantation sites were examined with immunohistochemistry and real-time PCR. The results revealed that the mRNA levels of ESR1, VEGFA, and Integrin αV and β3 were significantly increased in the high-dose FA group and significantly decreased in the folate deficiency group compared to the control group (p < 0.05). Based on these results, it can be concluded that FA supplementation before pregnancy has positive effects on the maintenance of pregnancy, and folate deficiency may lead to implantation disorders.

Integrin-linked kinase-frizzled 7 interaction maintains cancer stem cells to drive platinum resistance in ovarian cancer

BackgroundPlatinum-based chemotherapy regimens are a mainstay in the management of ovarian cancer (OC), but emergence of chemoresistance poses a significant clinical challenge. The persistence of ovarian cancer stem cells (OCSCs) at the end of primary treatment contributes to disease recurrence. Here, we hypothesized that the extracellular matrix protects CSCs during chemotherapy and supports their tumorigenic functions by activating integrin-linked kinase (ILK), a key enzyme in drug resistance.MethodsTCGA datasets and OC models were investigated using an integrated proteomic and gene expression analysis and examined ILK for correlations with chemoresistance pathways and clinical outcomes. Canonical Wnt pathway components, pro-survival signaling, and stemness were examined using OC models. To investigate the role of ILK in the OCSC-phenotype, a novel pharmacological inhibitor of ILK in combination with carboplatin was utilized in vitro and in vivo OC models.ResultsIn response to increased fibronectin secretion and integrin β1 clustering, aberrant ILK activation supported the OCSC phenotype, contributing to OC spheroid proliferation and reduced response to platinum treatment. Complexes formed by ILK with the Wnt receptor frizzled 7 (Fzd7) were detected in tumors and correlated with metastatic progression. Moreover, TCGA datasets confirmed that combined expression of ILK and Fzd7 in high grade serous ovarian tumors is correlated with reduced response to chemotherapy and poor patient outcomes. Mechanistically, interaction of ILK with Fzd7 increased the response to Wnt ligands, thereby amplifying the stemness-associated Wnt/β-catenin signaling. Notably, preclinical studies showed that the novel ILK inhibitor compound 22 (cpd-22) alone disrupted ILK interaction with Fzd7 and CSC proliferation as spheroids. Furthermore, when combined with carboplatin, this disruption led to sustained AKT inhibition, apoptotic damage in OCSCs and reduced tumorigenicity in mice.ConclusionsThis “outside-in” signaling mechanism is potentially actionable, and combined targeting of ILK-Fzd7 may lead to new therapeutic approaches to eradicate OCSCs and improve patient outcomes.

Using network pharmacology to discover potential drugs for hypertrophic scars.

Hypertrophic scarring is a disease of abnormal skin fibrosis caused by excessive fibroblast proliferation. Existing drugs have not achieved satisfactory therapeutic effects. To explore the molecular pathogenesis of hypertrophic scars and screen effective drugs for their treatment. Existing human hypertrophic scar RNA sequencing data were utilized to search for hypertrophic scar-related gene modules and key genes through weighted gene co-expression network analysis (WGCNA). Candidate compounds were screened in a compound library. Potential drugs were screened by molecular docking and verified in human hypertrophic scar fibroblasts and a mouse mechanical force hypertrophic scar model. WGCNA showed that hypertrophic scar-associated gene modules influence focal adhesion, the transforming growth factor (TGF)-β signalling pathway and other biologic pathways. Integrin β1 (ITGB1) is the hub protein. Among the candidate compounds obtained by computer virtual screening and molecular docking, crizotinib, sorafenib and SU11274 can inhibit the proliferation and migration of human hypertrophic scar fibroblasts and profibrotic gene expression. Crizotinib had the best effect on hypertrophic scar attenuation in mouse models. At the same time, mouse ITGB1 small interfering RNA can also inhibit mouse scar hyperplasia. ITGB1 and TGF-β signalling pathways are important for hypertrophic scar formation. Crizotinib could be a potential treatment drug for hypertrophic scars.

Integrin activating molecule-talin1 promotes skin fibrosis in systemic sclerosis.

Integrin-dependent cell adhesion and migration play important roles in systemic sclerosis (SSc). The roles of integrin activating molecules including talins and kindlins, however, are unclear in SSc. We aimed to explore the function of integrin activating molecules in SSc. Transcriptome analysis of skin datasets of SSc patients was performed to explore the function of integrin-activating molecules including talin1, talin2, kindlin1, kindlin2 and kindlin3 in SSc. Expression of talin1 in skin tissue was assessed by multiplex immunohistochemistry staining. Levels of talin1 in serum were determined by ELISA. The effects of talin1 inhibition were analyzed in human dermal fibroblasts by real-time PCR, western blot and flow cytometry. We identified that talin1 appeared to be the primary integrin activating molecule involved in skin fibrosis of SSc. Talin1 was significantly upregulated and positively correlates with the modified Rodnan skin thickness score (mRSS) and the expression of pro-fibrotic biomarkers in the skin lesions of SSc patients. Further analyses revealed that talin1 is predominantly expressed in the dermal fibroblasts of SSc skin and promotes fibroblast activation and collagen production. Additionally, talin1 primarily exerts its effects through integrin β1 and β5 in SSc. Overexpressed talin1 is participated in skin fibrosis of SSc, and talin1 appears to be a potential new therapeutic target for SSc.

ADAM12-Generated Basigin Ectodomain Binds β1 Integrin and Enhances the Expression of Cancer-Related Extracellular Matrix Proteins.

Desmoplasia is a common feature of aggressive cancers, driven by a complex interplay of protein production and degradation. Basigin is a type 1 integral membrane receptor secreted in exosomes or released by ectodomain shedding from the cell surface. Given that soluble basigin is increased in the circulation of patients with a poor cancer prognosis, we explored the putative role of the ADAM12-generated basigin ectodomain in cancer progression. We show that recombinant basigin ectodomain binds β1 integrin and stimulates gelatin degradation and the migration of cancer cells in a matrix metalloproteinase (MMP)- and β1-integrin-dependent manner. Subsequent in vitro and in vivo experiments demonstrated the altered expression of extracellular matrix proteins, including fibronectin and collagen type 5. Thus, we found increased deposits of collagen type 5 in the stroma of nude mice tumors of the human tumor cell line MCF7 expressing ADAM12-mimicking the desmoplastic response seen in human cancer. Our findings indicate a feedback loop between ADAM12 expression, basigin shedding, TGFβ signaling, and extracellular matrix (ECM) remodeling, which could be a mechanism by which ADAM12-generated basigin ectodomain contributes to the regulation of desmoplasia, a key feature in human cancer progression.