Integrin Αvβ3 Expression Research Articles

Molecular Imaging of Steroid-Induced Osteonecrosis of the Femoral Head through iRGD-Targeted Microbubbles.

Osteonecrosis of the femoral head (ONFH) is a disease that is commonly seen in the clinic, but its detection rate remains limited, especially at the early stage. We developed an ultrasound molecular imaging (UMI) approach for early diagnosis of ONFH by detecting the expression of integrin αvβ3 during the pathological changes in steroid-induced osteonecrosis of the femoral head (SIONFH) in rat models. The integrin αvβ3-targeted PLGA or lipid microbubbles modified with iRGD peptides were fabricated and characterized. Their adhesion efficiency to mouse brain microvascular endothelial cells in vitro was examined, and the better LIPOiRGD was used for further in vivo molecular imaging of SIONFH rats at 1, 3 and 5 weeks; revealing significantly higher UMI signals could be observed in the 3-week and 5-week SIONFH rats but not in the 1-week SIONFH rats in comparison with the non-targeted microbubbles (32.75 ± 0.95 vs. 0.17 ± 0.09 for 5 weeks, p < 0.05; 5.60 ± 1.31 dB vs. 0.94 ± 0.81 dB for 3 weeks, p < 0.01; 1.13 ± 0.13 dB vs. 0.73 ± 0.31 dB for 1 week, p > 0.05). These results were consistent with magnetic resonance imaging data and confirmed by immunofluorescence staining experiments. In conclusion, our study provides an alternative UMI approach to the early evaluation of ONFH.

Loss of ATRX promotes aggressive features of osteosarcoma with increased NF-κB signaling and integrin binding.

Osteosarcoma (OS) is a lethal disease with few known targeted therapies. Here, we show that decreased ATRX expression is associated with more aggressive tumor cell phenotypes, including increased growth, migration, invasion, and metastasis. These phenotypic changes correspond with activation of NF-κB signaling, extracellular matrix remodeling, increased integrin αvβ3 expression, and ETS family transcription factor binding. Here, we characterize these changes in vitro, in vivo, and in a data set of human OS patients. This increased aggression substantially sensitizes ATRX-deficient OS cells to integrin signaling inhibition. Thus, ATRX plays an important tumor-suppression role in OS, and loss of function of this gene may underlie new therapeutic vulnerabilities. The relationship between ATRX expression and integrin binding, NF-κB activation, and ETS family transcription factor binding has not been described in previous studies and may impact the pathophysiology of other diseases with ATRX loss, including other cancers and the ATR-X α thalassemia intellectual disability syndrome.

Semaphorin 3F induces colorectal cancer cell chemosensitivity by promoting P27 nuclear export.

Colorectal adenocarcinoma (CRC) is the third most common malignancy worldwide. Metastatic CRC has a poor prognosis because of chemotherapy resistance. Our previous study demonstrated that semaphorin 3F (SEMA3F) signaling may contribute to reversing chemotherapy resistance in CRC cells by reducing E-cadherin and integrin αvβ3 expression levels. Another study showed that upregulation of p27 significantly increase the expression of E-cadherin and integrin. This study aimed to evaluate the effect of SEMA3F on P27 and whether it can reverse resistance in CRC cells. We compared the chemosensitivity of human colorectal cancer cell lines with different SEMA3F expression levels to 5-Fu through cell experiment and animal experiment. Then the interaction between SEMA3F and p27 and its possible mechanism were explored by Western Blot, immunofluorescence and immunocoprecipitation. We also compared the disease-free survival of 118 CRC patients with high or low expression of SEMA3F.The results showed that overexpresstion of SEMA3F enhanced the chemotherapy sensitivity and apoptosis of CRC cells in vitro and in vivo. Among 118 postoperative CRC specimens, the disease-free survival of patients with positive SEMA3F expression was significantly longer than that with negative SEMA3F expression after adjuvant treatment. Upregulation of SEMA3F in multicellular spheroid culture (MSC) could increase p27 phosphorylation at serine 10 (Ser10), subsequently promote the cytosolic translocation of P27. Overall, our results reveal a novel molecular mechanism: SEMA3F mediates the degradation of p27 and regulates its subcellular localization to enhance chemosensitivity to 5-Fu in CRC cells, rather than inhibits p27 expression.

Specific activation of embryonic IFNAR1 and endometrial IFNAR2 induced by embryonic IFNτ directs normal uterine fate for bovine early implantation

Interferon-tau (IFNτ), as an antiluteolytic factor secreted by trophoderm during the pregnancy of ruminants, actually functions by activating the IFNτ receptor 1 (IFNAR1) and IFNτ receptor 2 (IFNAR2). However, it has not been clearly understood how IFNτ-IFNAR cascade regulation processes between the embryo and uterine epithelial cells in ruminants. In this study, we found the expression and location of IFNτ in the bovine blastocysts from different production sources. IFNτ, IFNAR1 and IFNAR2 were all located in the trophoblast cells of the blastocyst. However, the fluorescence intensity of IFNAR1 was consistent with that of IFNτ. Antagonizing the expressions of IFNAR1 and IFNAR2 in embryos and co-culture with endometrial epithelium cells (EECs) reduced the expressions of Integrin αv β3, WNT7A, and ISG15 in EECs. Knocking out IFNAR1 and IFNAR2 reduce the expressions of Integrin αv β3 and WNT7A in EECs, the deletion of IFNAR2 gene has a greater impact than that of IFNAR1 gene. IFNAR1-/IFNAR2+ and IFNAR1+/IFNAR2- EECs were co-cultured with IVF embryos, the expression of Integrin αv β3 was inhibited, and the inhibition of IFNAR1+/IFNAR2- was much stronger, and the expression of WNT7A was not inhibited. The expressions of Integrin αv β3 and WNT7A did not change significantly after IFNAR1-/IFNAR2+ and IFNAR1+/IFNAR2- co-culture with PA embryos. All of these results strongly suggest that specific activation of embryonic IFNAR1 and endometrial IFNAR2 induced by embryonic IFNτ directs normal uterine preparation for bovine early implantation.

Noninvasive photoacoustic computed tomography/ultrasound imaging toidentify high-risk atherosclerotic plaques.

Noninvasive detection ofhigh-risk plaques is still challenging. In this study, we aimed to noninvasively assess αvβ3-integrin expressionusing a customed photoacoustic (PA) computed tomography (PACT)/ultrasound (US) system in atheroscleroticlesions of varying degrees of severity and to explore its potential value for detecting high-risk plaques. We constructed αvβ3-integrin-targeted ultrasmall gold nanorods (AuNRs) with cyclo Arg-Gly-Asp (cRGD) and tested their properties. Employing C57BL/6J (wild-type, WT) mice and apolipoprotein E gene knockout (ApoE-/-) mice fed either a chow diet or a high-fat/high-cholesterol diet (HFHCD), we established varying degrees of lesion severity. In vivo PACT/US imaging was performed to assess αvβ3-integrin expression in the 4 groups by cRGD-AuNRs. Further histopathologic examination was conducted to evaluate the plaque vulnerability indicators. The data showed thatcRGD-AuNRs exhibited excellent photothermal conversion capacity, stability, targeting ability, and biocompatibility. The immunohistochemical results indicated that αvβ3-integrin was upregulated with increasing aggravation of the lesions. In vivo PACT/US imaging showed good consistency with αvβ3-integrin expression. Notably, ApoE-/- mice fed a HFHCD showed an abrupt PA intensity increase compared with the other groups. The histopathologic examination verified that the atherosclerotic plaques of ApoE-/- mice fed the HFHCD developed unstable phenotypes. Correlation analysis showed that PA intensity was mainly related to inflammation and angiogenesis among all ofthe indicators. Our data indicated that αvβ3-integrin is an effective indicator of plaque instability, and noninvasive PACT/US molecular imaging assessment ofαvβ3-integrin holds promise in detecting high-risk plaques.

Yikang decoction facilitates embryo implantation in mice with implantation dysfunction via upregulation of LIF expression

ObjectiveThe present study investigates the effects and mechanisms of Yikang decoction on embryo implantation in mice. MethodsTotally, mature female mice were randomly divided into four groups: normal, implantation failure (mifepristone treatment), Yikang decoction treatment (mifepristone and Yikang decoction treatment), and control (mifepristone and physiological saline treatment) groups. The efficacy of Yikang decoction was evaluated by the adhesion of uterine endometrial cells. The expression of leukemia inhibitory factor (LIF) and integrin αvβ3 in the endometrium were detected by real-time quantitative PCR and western blot. In addition, mouse endometrial cells were transfected with LIF specific siRNA-1, and the expression of LIF and αvβ3 were detected. ResultsThe number of embryos markedly decreased after mifepristone treatment. The adhesion of endometrial cells in the Yikang decoction treatment group significantly increased, when compared to the control group. The expression of LIF and integrin αvβ3 was significantly reduced by mifepristone, but the attenuated expression of LIF and αvβ3 was markedly reversed by treatment with Yikang decoction. In addition, after LIF siRNA-1 transfection, the expression of integrin αvβ3 significantly decreased (P < 0.01). The correlation analysis revealed a significant positive correlation between LIF and αvβ3 protein expression. ConclusionYikang decoction can regulate the expression of αvβ3 and increase cell adhesion by upregulating the expression of LIF, thereby improving embryo implantation in mice. These data suggest that Yikang decoction may have therapeutic effect in treating infertility.

Integrin-αvβ3 as a Therapeutic Target in Glioblastoma: Back to the Future?

Glioblastoma (GBM), the most common primary malignant brain tumor, is associated with a dismal prognosis. Standard therapies including maximal surgical resection, radiotherapy, and temozolomide chemotherapy remain poorly efficient. Improving GBM treatment modalities is, therefore, a paramount challenge for researchers and clinicians. GBMs exhibit the hallmark feature of aggressive invasion into the surrounding tissue. Among cell surface receptors involved in this process, members of the integrin family are known to be key actors of GBM invasion. Upregulation of integrins was reported in both tumor and stromal cells, making them a suitable target for innovative therapies targeting integrins in GBM patients, as their impairment disrupts tumor cell proliferation and invasive capacities. Among them, integrin-αvβ3 expression correlates with high-grade GBM. Driven by a plethora of preclinical biological studies, antagonists of αvβ3 rapidly became attractive therapeutic candidates to impair GBM tumorigenesis. In this perspective, the advent of nuclear medicine is currently one of the greatest components of the theranostic concept in both preclinical and clinical research fields. In this review, we provided an overview of αvβ3 expression in GBM to emphasize the therapeutic agents developed. Advanced current and future developments in the theranostic field targeting αvβ3 are finally discussed.

Cathepsin K contributed to disturbed flow-induced atherosclerosis is dependent on integrin-actin cytoskeleton–NF–κB pathway

Atherosclerosis is a chronic inflammatory disease, occurring preferentially in bifurcation, branching, and bending of blood vessels exposed to disturbed flow. Disturbed flow in atheroprone areas activates elevated proteases, degrading elastin lamellae and collagenous matrix, resulting in endothelial dysfunction and vascular remodeling. As a mediator for extracellular matrix protein degradation, cathepsin K (CTSK) was directly regulated by hemodynamics and contributed to atherosclerosis. The mechanism of CTSK responding to disturbed flow and contributing to disturbed flow-induced atherosclerosis is unclear. In this study, the partial carotid ligation model of mice and in vitro disturbed shear stress model were constructed to explore the contribution and potential mechanism of CTSK in atherosclerosis. Our results indicated that CTSK elevated in the disturbed flow area in vivo and in vitro along with endothelial inflammation and atherogenesis. Additionally, the expression of integrin αvβ3 was upregulated in these atheroprone areas. We found that inhibition of the integrin αvβ3-cytoskeleton pathway could significantly block the activation of NF-κB and the expression of CTSK. Collectively, our findings unraveled that disturbed flow induces increased CTSK expression, and contributes to endothelial inflammation and vascular remodeling, leading to atherogenesis eventually. This study is helpful to provide new enlightenment for the therapy of atherosclerosis.

Heterodimeric RGD-NGR PET Tracer for the Early Detection of Pancreatic Cancer.

Pancreatic ductal adenocarcinoma (PDAC) is the most lethal gastrointestinal cancer, and its poor prognosis is highly associated with the lack of an efficient early detection technology. Here, we report that RGD-NGR heterodimer labeled with PET isotope could be applied in PDAC early detection. The RGD-NGR tracer was first compared with its corresponding monomeric counterparts via PET imaging studies using mice bearing a subcutaneous BxPC3 tumor. Subsequently, the RGD-NGR tracer was evaluated in autochthonous mouse models with spontaneously developed late stage PanIN lesions (KCER mice) or PDAC (KPC mice) via both PET imaging studies and ex vivo biodistribution studies. Furthermore, a comparison between 2-deoxy-2[18F]fluoro-D-glucose ([18F]F-FDG) and the RGD-NGR tracer was conducted via PET imaging of the same KCH mouse bearing spontaneously developed PDAC. H&E staining was performed to confirm the malignant pancreatic tissue in the KCH mouse. Immunofluorescence staining was performed to confirm the expression of integrin αVβ3 and CD13. The RGD-NGR tracer exhibited improved in vivo performance as compared with its corresponding monomeric counterparts on the subcutaneous BxPC3 tumor mouse model. Subsequent evaluation in autochthonous mouse models demonstrated its capability to detect both pre-malignant and malignant pancreases. Further comparison with [18F]F-FDG revealed the superiority of the proposed heterodimer in imaging spontaneously developed PDAC. H&E staining confirmed the malignant pancreatic tissue in the KCH mouse, while the expression of both integrin αVβ3 and CD13 receptors was demonstrated with immunofluorescence staining. The proposed RGD-NGR heterodimer possesses the potential to be applied in the PDAC early detection for high-risk populations.

IRE1α drives lung epithelial progenitor dysfunction to establish a niche for pulmonary fibrosis.

After lung injury, damage-associated transient progenitors (DATPs) emerge, representing a transitional state between injured epithelial cells and newly regenerated alveoli. DATPs express profibrotic genes, suggesting that they might promote idiopathic pulmonary fibrosis (IPF). However, the molecular pathways that induce and/or maintain DATPs are incompletely understood. Here we show that the bifunctional kinase/RNase-IRE1α-a central mediator of the unfolded protein response (UPR) to endoplasmic reticulum (ER) stress is a critical promoter of DATP abundance and function. Administration of a nanomolar-potent, monoselective kinase inhibitor of IRE1α (KIRA8)-or conditional epithelial IRE1α gene knockout-both reduce DATP cell number and fibrosis in the bleomycin model, indicating that IRE1α cell-autonomously promotes transition into the DATP state. IRE1α enhances the profibrotic phenotype of DATPs since KIRA8 decreases expression of integrin αvβ6, a key activator of transforming growth factor β (TGF-β) in pulmonary fibrosis, corresponding to decreased TGF-β-induced gene expression in the epithelium and decreased collagen accumulation around DATPs. Furthermore, IRE1α regulates DNA damage response (DDR) signaling, previously shown to promote the DATP phenotype, as IRE1α loss-of-function decreases H2AX phosphorylation, Cdkn1a (p21) expression, and DDR-associated secretory gene expression. Finally, KIRA8 treatment increases the differentiation of Krt19CreERT2-lineage-traced DATPs into type 1 alveolar epithelial cells after bleomycin injury, indicating that relief from IRE1α signaling enables DATPs to exit the transitional state. Thus, IRE1α coordinates a network of stress pathways that conspire to entrap injured cells in the DATP state. Pharmacological blockade of IRE1α signaling helps resolve the DATP state, thereby ameliorating fibrosis and promoting salutary lung regeneration.

GnRH agonist treatment regulates IL-6 and IL-11 expression in endometrial stromal cells for patients with HRT regiment in frozen embryo transfer cycles

To evaluate the effect of gonadotropin-releasing hormone agonist (GnRHa) pretreatment time on clinical outcomes of patients who underwent endometrial preparation in HRT cycles and the molecular mechanism in frozen-thawed embryo transfer (FET) cycles, we retrospectively chose 1143 cycles and separated four groups. Endometrial tissues were collected from 44 patients who were cancelled on the day of embryo transfer (there were 10 patients refused to collect endometrium) and were tested for endometrial receptivity marker mRNA and miR-124-3p expression. Furthermore, endometrial stromal cells (ESCs) were transfected to investigate the molecular mechanism. The clinical pregnancy rate and live birth rate were significantly high in group B. The endometrial expression of the IL-6 and IL-11 mRNAs was significantly increased in groups with GnRHa pretreatment compared with group A without the GnRHa pretreatment. Similar results were obtained for the endometrial receptivity markers LIF and integrin αvβ3. The groups treated with GnRHa exhibited a progressive and significant time-dependent decrease in the IL-6 and IL-11 mRNA. In contrast, the levels of LIF and integrin αvβ3 expression remained unaltered among group B-D. In addition, transfection of ESCs with miR-124-3p mimics significantly reduced levels of the IL-6 and IL-11 mRNAs and proteins. The luciferase report assay demonstrated that IL-6 and IL-11 is a target gene of miR-124-3p. The results showed that ultra-long GnRHa administration can improve outcomes, especially after 3 cycles of GnRHa pretreatment, and endometrial receptivity through IL-6 and IL-11 expression levels of ESC regulated by the miR-124-3p for patients with HRT, who underwent FET cycles.

Inhibition of integrin αvβ6 sparks T-cell antitumor response and enhances immune checkpoint blockade therapy in colorectal cancer

BackgroundIntegrin αvβ6 is a heterodimeric cell surface protein whose cellular expression is determined by the availability of the integrin β6 subunit (ITGB6). It is expressed at very low levels in...

Fibronectin-Coated Metal-Phenolic Networks for Cooperative Tumor Chemo-/Chemodynamic/Immune Therapy via Enhanced Ferroptosis-Mediated Immunogenic Cell Death.

The development of nanomedicine formulations to overcome the disadvantages of traditional chemotherapeutic drugs and integrate cooperative theranostic modes still remains challenging. Herein, we report the facile construction of a multifunctional theranostic nanoplatform based on doxorubicin (DOX)-loaded tannic acid (TA)-iron (Fe) networks (for short, TAF) coated with fibronectin (FN) for combination tumor chemo-/chemodynamic/immune therapy under the guidance of magnetic resonance (MR) imaging. We show that the DOX-TAF@FN nanocomplexes created through in situ coordination of TA and Fe(III) and physical coating with FN have a mean particle size of 45.0 nm, are stable, and can release both DOX and Fe in a pH-dependent manner. Due to the coexistence of the TAF network and DOX, significant immunogenic cell death can be caused through enhanced ferroptosis of cancer cells via cooperative Fe-based chemodynamic therapy and DOX chemotherapy. Through further treatment with programmed cell death ligand 1 antibody for an immune checkpoint blockade, the tumor treatment efficacy and the associated immune response can be further enhanced. Meanwhile, with FN-mediated targeting, the DOX-TAF@FN platform can specifically target tumor cells with high expression of αvβ3 integrin. Finally, the TAF network also enables the DOX-TAF@FN to have an r1 relaxivity of 6.1 mM-1 s-1 for T1-weighted MR imaging of tumors. The developed DOX-TAF@FN nanocomplexes may represent an updated multifunctional nanosystem with simple compositions for cooperative MR imaging-guided targeted chemo-/chemodynamic/immune therapy of tumors.

Study of the efficiency of cellular accumulation of doxorubicin supplied with a targeted delivery system based on phospholipid nanoparticles with integrin-directed peptide

Chemotherapeutic agents containing targeted systems are a promising pathway to increase the effectiveness of glioblastoma treatment. Specific proteins characterized by increased expression on the surface of tumor cells are considered as possible targets. Integrin αvβ3 is one of such proteins on the cell surface. It effectively binds the cyclic Arg-Gly-Asp (cRGD) peptide. In this study, the cRGD peptide-modified doxorubicin (Dox) phospholipid composition was investigated. The particle size of this composition was 43.76±2.09 nm, the ζ-potential was 4.33±0.54 mV. Dox was almost completely incorporated into the nanoparticles (99.7±0.58%). The drug release increased in an acidic medium (at pH 5.0 of about 35±3.2%). The total accumulation and internalization of Dox used the composition of phospholipid nanoparticles with the targeted vector was 1.4-fold higher as compared to the free form. In the HeLa cell line (not expressing αvβ3 integrin) this effect was not observed. These results suggest the prospects of using the cyclic RGD peptide in the delivery of Dox to glioblastoma cells and the feasibility of further investigation of the mechanism of action of the entire composition as a whole.

Letrozole promotes the expression of integrin αvβ3 and HOXA10 in endometrium of endometriosis

ABSTRACT Endometriosis is a common estrogen-dependent chronic inflammatory disease that leads to infertility in women of reproductive age. Perhaps infertility reflects the reduced expression of integrin αvβ3 and HOXA10 in endometriosis. Previous studies have shown that administration of letrozole, a non-steroidal aromatase inhibitor for cancer treatment, increased the clinical pregnancy rate in women with endometriosis, but the mechanisms remain to be determined. In this communication, a rat model of endometriosis was established. Animals were treated with letrozole at 2ug/kg of body weight, intragastric administration for 15 consecutive days. Letrozole increased the expression of αvβ3 and HOXA10 in the endometriosis model and endometrial receptivity. Abbreviations: WOI: window of implantation; RGD: Arg-Gly-Asp; HOX: homeobox; E2: estradiol; SPF: specific pathogen-free.

αVβ3 Integrin Expression Is Essential for Replication of Mosquito and Tick-Borne Flaviviruses in Murine Fibroblast Cells.

The Flavivirus genus includes a number of important viruses that are pathogenic to humans and animals and are responsible for outbreaks across the globe. Integrins, a family of heterodimeric transmembrane molecules expressed in all nucleated cells mediate critical functions of cell physiology and cell cycle. Integrins were previously postulated to be involved in flavivirus entry and to modulate flavivirus replication efficiency. In the present study, mouse embryonic fibroblasts (MEF), lacking the expression of αVβ3 integrin (MEF-αVβ3−/−), were infected with four different flaviviruses, namely yellow fever virus (YFV), West Nile virus (WNV), Usutu virus (USUV) and Langat virus (LGTV). The effects of the αVβ3 integrin absence in double-knockout MEF-αVβ3−/− on flavivirus binding, internalization and replication were compared to the respective wild-type cells. Binding to the cell surface for all four flaviviruses was not affected by the ablation of αVβ3 integrin, whereas internalization of USUV and WNV was slightly affected by the loss of αVβ3 integrin expression. Most interestingly, the deletion of αVβ3 integrin strongly impaired replication of all flaviviruses with a reduction of up to 99% on virus yields and a strong reduction on flavivirus anti-genome RNA synthesis. In conclusion, our results demonstrate that αVβ3 integrin expression in flavivirus-susceptible cell lines enhances the flavivirus replication.

The Tongue Squamous Carcinoma Cell Line Cal27 Primarily Employs Integrin α6β4-Containing Type II Hemidesmosomes for Adhesion Which Contribute to Anticancer Drug Sensitivity.

Integrins are heterodimeric cell surface glycoproteins used by cells to bind to the extracellular matrix (ECM) and regulate tumor cell proliferation, migration and survival. A causative relationship between integrin expression and resistance to anticancer drugs has been demonstrated in different tumors, including head and neck squamous cell carcinoma. Using a Cal27 tongue squamous cell carcinoma model, we have previously demonstrated that de novo expression of integrin αVβ3 confers resistance to several anticancer drugs (cisplatin, mitomycin C and doxorubicin) through a mechanism involving downregulation of active Src, increased cell migration and invasion. In the integrin αVβ3 expressing Cal27-derived cell clone 2B1, αVβ5 expression was also increased, but unrelated to drug resistance. To identify the integrin adhesion complex (IAC) components that contribute to the changes in Cal27 and 2B1 cell adhesion and anticancer drug resistance, we isolated IACs from both cell lines. Mass spectrometry (MS)-based proteomics analysis indicated that both cell lines preferentially, but not exclusively, use integrin α6β4, which is classically found in hemidesmosomes. The anticancer drug resistant cell clone 2B1 demonstrated an increased level of α6β4 accompanied with increased deposition of a laminin-332-containing ECM. Immunofluorescence and electron microscopy demonstrated the formation of type II hemidesmosomes by both cell types. Furthermore, suppression of α6β4 expression in both lines conferred resistance to anticancer drugs through a mechanism independent of αVβ3, which implies that the cell clone 2B1 would have been even more resistant had the upregulation of α6β4 not occurred. Taken together, our results identify a key role for α6β4-containing type II hemidesmosomes in regulating anticancer drug sensitivity.

CCL4 Stimulates Cell Migration in Human Osteosarcoma via the mir-3927-3p/Integrin αvβ3 Axis.

Osteosarcoma is the most common type of primary malignant bone cancer, and it is associated with high rates of pulmonary metastasis. Integrin αvβ3 is critical for osteosarcoma cell migratory and invasive abilities. Chemokine (C-C motif) ligand 4 (CCL4) has diverse effects on different cancer cells through its interaction with its specific receptor, C-C chemokine receptor type 5 (CCR5). Analysis of mRNA expression in human osteosarcoma tissue identified upregulated levels of CCL4, integrin αv and β3 expression. Similarly, an analysis of records from the Gene Expression Omnibus (GEO) dataset showed that CCL4 was upregulated in human osteosarcoma tissue. Importantly, the expression of both CCL4 and integrin αvβ3 correlated positively with osteosarcoma clinical stages and lung metastasis. Analysis of osteosarcoma cell lines identified that CCL4 promotes integrin αvβ3 expression and cell migration by activating the focal adhesion kinase (FAK), protein kinase B (AKT), and hypoxia inducible factor 1 subunit alpha (HIF-1α) signaling pathways, which can downregulate microRNA-3927-3p expression. Pharmacological inhibition of CCR5 by maraviroc (MVC) prevented increases in integrin αvβ3 expression and cell migration. This study is the first to implicate CCL4 as a potential target in the treatment of metastatic osteosarcoma.

Integrin αvβ3 and disulfide bonds play important roles in NGR-retargeted adenovirus transduction efficiency

AimsAdenoviruses that have CNGRCVSGCAGRC peptide inserted into fiber (AdFNGR) or hexon (AdHNGR) protein, respectively, showed increased transduction of endothelial cells. In this study we investigated if cysteines within the CNGRCVSGCAGRC sequence inserted into Ad serotype 5 Ad5 fiber or hexon protein form disulfide bond(s) and whether they play a role in retargeting potential of AdFNGR and AdHNGR. MethodsTransduction efficiency of adenoviruses was done by counting infected cells under the microscope. Adenovirus attachment and internalization were measured by qPCR. Flow cytometry was used to evaluate the expression of CD13 and integrins. Gene knockdown was achieved by transfection of small interfering RNA. Mass spectrometry was used for determining disulfide bonds in adenovirus fiber and hexon protein. Molecular modeling was use to predict interaction of CNGRCVSGCAGRC peptide and CD13. Key findingsAdFNGR and AdHNGR attach better to CD13 and/or αvβ3 integrin-positive cells than Adwt. Reducing disulfide bonds using DTT decreased transduction efficiency and attachment of both AdFNGR and AdHNGR. Cysteins from CNGRCVSGCAGRC peptide within AdHNGR do not form disulfide bonds. Knockdown of αvβ3 integrin reduced increased transduction efficiency of both AdFNGR and AdHNGR, while CD13 knockdown had no effect, indicating that retargeting properties of these viruses rely mainly on αvβ3 integrin expression. SignificanceInsertion site of NGR-containing peptides as well as NGR flanking residues are critical for receptor binding affinity/specificity and transduction efficiency of NGR retargeted adenoviral vectors.

Single-Cell Proteomic Profiling Identifies Nanoparticle Enhanced Therapy for Triple Negative Breast Cancer Stem Cells.

Breast cancer remains a major cause of cancer-related deaths in women worldwide. Chemotherapy-promoted stemness and enhanced stem cell plasticity in breast cancer is a cause for great concern. The discovery of drugs targeting BCSCs was suggested to be an important advancement in the establishment of therapy that improves the efficacy of chemotherapy. In this work, by using single-cell mass cytometry, we observed that stemness in spheroid-forming cells derived from MDA-MB-231 cells was significantly increased after doxorubicin administration and up-regulated integrin αvβ3 expression was also observed. An RGD-included nanoparticle (CS-V) was designed, and it was found that it could promote doxorubicin’s efficacy against MDA-MB-231 spheroid cells. The above observations suggested that the combination of RGD-included nanoparticles (CS-V) with the chemo-drug doxorubicin could be developed as a potential therapy for breast cancer.