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Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is responsible for the current coronavirus disease pandemic. With the rapid evolution of variant strains, finding effective spike protein inhibitors is a logical and critical priority. Angiotensin-converting enzyme 2 (ACE2) has been identified as the functional receptor for SARS-CoV-2 viral entry, and thus related therapeutic approaches associated with the spike protein–ACE2 interaction show a high degree of feasibility for inhibiting viral infection. Our computer-aided drug design (CADD) method meticulously analyzed more than 260,000 compound records from the United States National Cancer Institute (NCI) database, to identify potential spike inhibitors. The spike protein receptor-binding domain (RBD) was chosen as the target protein for our virtual screening process. In cell-based validation, SARS-CoV-2 pseudovirus carrying a reporter gene was utilized to screen for effective compounds. Ultimately, compounds C2, C8, and C10 demonstrated significant antiviral activity against SARS-CoV-2, with estimated EC50 values of 8.8 μM, 6.7 μM, and 7.6 μM, respectively. Using the above compounds as templates, ten derivatives were generated and robust bioassay results revealed that C8.2 (EC50 = 5.9 μM) exhibited the strongest antiviral efficacy. Compounds C8.2 also displayed inhibitory activity against the Omicron variant, with an EC50 of 9.3 μM. Thus, the CADD method successfully discovered lead compounds binding to the spike protein RBD that are capable of inhibiting viral infection.

Introduction: Cigarette smoking is the main risk factor for lung cancer. MSCs in the TME promoting tumor angiogenesis, growth, and metastasis. SIBLING proteins enable cancer cells to extend, invade and metastasize. Objectives: Cigarette smoke promotes the progression and metastasis of lung cancer, although how this occurs is poorly understood. We evaluated the impact of whether cigarette smoking motivates SIBLING protein expression and is involved in MSC-mediated lung tumor metastasis. Methods: We investigated the expression of OPN in the Gene Expression Omnibus (GEO) databases and confirmed the results by immunohistochemistry (IHC), qPCR and Western blotting (WB) of lung cancer cells and tissues. The effect of OPN on the recruitment and adhesion of mesenchymal stem cells (MSCs) to lung cancer cells and lung cancers metastasis was investigated by Transwell, adhesion assays. A series of in vitro and in vivo experiments were conducted to demonstrate the mechanisms by which OPN modulates recruitment and adhesion of MSCs to lung cancer cells and lung cancer metastasis. Results: Cigarette smoke extract (CSE) and benzo[α]pyrene (B[α]P) increased levels of OPN expression and facilitated the recruitment and adhesion of MSCs to lung cancer cells via JAK2/STAT3 signaling. We also observed that OPN promotes tumor-associated MSC (TA-MSC) formation through the OPN receptor (integrins αvβ1, αvβ3, αvβ5 or CD44), inducing lung cancer cell migration and invasion. In an orthotopic mouse model of lung cancer, increases in OPN expression promoted by cigarette smoke upregulated MSC recruitment and facilitated lung cancer metastasis. Knockdown of OPN expression inhibited cigarette smoke-induced lung cancer metastasis in vivo. Conclusion: Cigarette smoke increases OPN expression through the JAK2/STAT3 signaling pathway to attract MSC cell recruitment and promote lung cancer metastasis. Our findings offer important insights into how lung cancer metastasis develops in smokers.

Abstract Background Human placenta-derived multipotent cells (hPDMCs) are isolated from a source uncomplicated by ethical issues and are ideal for therapeutic applications because of their capacity for multilineage differentiation and proven immunosuppressive properties. It is known that heat shock preconditioning induces the upregulation of heat shock proteins (HSPs), which enhance survival and engraftment of embryonic stem cells (ESCs) during transplantation in live animal models, although whether heat shock preconditioning has the same effects in hPDMCs is unclear. Methods The hPDMCs were isolated from placenta of healthy donors. The cells were treated with heat shock (43 °C, 15 min), followed by evaluation of cell viability. Furthermore, the HSPs expression was assessed by Western blot, qPCR. The reactive oxygen species (ROS) production and signal pathway activation were determined by flow cytometry and Western blot, respectively. The regulatory pathways involved in HSPs expression were examined by pretreatment with chemical inhibitors, and siRNAs of MAPK, Akt, and heat shock factor 1 (HSF1), followed by determination of HSPs expression. Results This study demonstrates that heat shock treatment induced ROS generation and HPSs expression in hPDMCs. Heat shock stimulation also increased p38 MAPK and Akt phosphorylation. These effects were reduced by inhibitors of ROS, p38 MAPK and Akt. Moreover, we found that heat shock treatment enhanced nuclear translocation of the HSF1 in hPDMCs, representing activation of HSF1. Pretreatment of hPDMCs with ROS scavengers, SB203580 and Akt inhibitors also reduced the translocation of HSF1 induced by heat shock. Conclusions Our data indicate that heat shock acts via ROS to activate p38 MAPK and Akt signaling, which subsequently activates HSF1, leading to HSP activation and contributing to the protective role of hPDMCs.

Abstract Background Although the powerful clinical effects of radiofrequency and microwave ablation have been established, such ablation is associated with several limitations, including a small ablation size, a long ablation time, the few treatment positioning, and biosafety risks. To overcome these limitations, biosafe and efficient magnetic ablation was achieved in this study by using biocompatible liquid gallium as an ablation medium and a contrast medium for imaging. Results Magnetic fields with a frequency (f) lower than 200 kHz and an amplitude (H) × f value lower than 5.0 × 109 Am−1 s−1 were generated using the proposed method. These fields could generate an ablation size of 3 cm in rat liver lobes under a temperature of approximately 300 °C and a time of 20 s. The results of this study indicate that biomedical gallium can be used as a contrast medium for the positioning of gallium injections and the evaluation of ablated tissue around a target site. Liquid gallium can be used as an ablation medium and imaging contrast medium because of its stable retention in normal tissue for at least 3 days. Besides, the high anticancer potential of gallium ions was inferred from the self-degradation of 100 µL of liquid gallium after around 21 days of immersion in acidic solutions. Conclusions The rapid wireless ablation of large or multiple lesions was achieved through the simple multi-injection of liquid gallium. This approach can replace the currently favoured procedure involving the use of multiple ablation probes, which is associated with limited benefits and several side effects. Methods Magnetic ablation was confirmed to be highly efficient by the consistent results obtained in the simulation and in vitro tests of gallium and iron oxide as well as the electromagnetic specifics and thermotherapy performance comparison detailed in this study Ultrasound imaging, X-ray imaging, and magnetic resonance imaging were found to be compatible with the proposed magnetic ablation method. Self-degradation analysis was conducted by mixing liquid gallium in acidic solutions with a pH of approximately 5–7 (to imitate a tumour-containing microenvironment). X-ray diffraction was used to identify the gallium oxides produced by degraded gallium ions.

Abstract Chondrosarcoma is a malignancy of soft tissue and bone that has a high propensity to metastasize to distant organs. Nerve growth factor (NGF) is critical for neuronal cell growth, apoptosis, and differentiation, and also appears to promote the progression and metastasis of several different types of tumors, although the effects of NGF upon chondrosarcoma mechanisms are not very clear. We report that NGF facilitates lysyl oxidase (LOX)-dependent cellular migration and invasion in human chondrosarcoma cells, and that NGF overexpression enhances lung metastasis in a mouse model of chondrosarcoma. NGF-induced stimulation of LOX production and cell motility occurs through the inhibition of miR-149-5p expression, which was reversed by PI3K, Akt, and mTOR inhibitors and their respective short interfering RNAs. Notably, levels of NGF and LOX expression correlated with tumor stage in human chondrosarcoma samples. Thus, NGF appears to be a worthwhile therapeutic target for metastatic chondrosarcoma.

Oral cancer, constituted up to 90% by squamous cell carcinomas, is a significant health burden globally. Grape seed proanthocyanidins (PA) have been suggested as a potential chemopreventive agent for oral cancer. However, their efficacy can be restricted due to the low bioavailability and bioaccessibility. Inspired by sandcastle worm adhesive, we adapted the concept of complex coacervation to generate a new type of drug delivery platform. Complex coacervates are a dense liquid phase formed by the associative separation of a mixture of oppositely charged polyelectrolytes, can serve as a drug delivery platform to protect labile cargo. In this study, we developed a complex coacervates-based delivery of PA. The release kinetics was measured, and anticancer effects were determined in two human tongue squamous cell carcinoma cell lines. The results showed that complex coacervate successfully formed and able to encapsulate PA. Additionally, PA were steadily released from the system in a pH-dependent manner. The drug delivery system could significantly inhibit the cell proliferation, migration, and invasion of cancer cells. Moreover, it could markedly reduce the expression of certain matrix metalloproteinases (MMP-2, 9, and 13) crucial to metastatic processes. We also found that suppression of protein kinase B (Akt) pathway might be the underlying mechanism for these anticancer activities. Taken together, complex coacervates-based delivery of PA can act as an effective anticancer approach for oral cancer therapy.

The diagnosis of liquid and solid biopsies by different instruments makes the clinic loading difficult in many aspects. Given the compositions of magnetic particles (MPs) with diverse characterizations and the innovative acoustic type of vibration sample magnetometer (VSM), the versatile, accessible magnetic diagnosis platform was proposed to meet clinical demands, such as low loading for multiple biopsies. In liquid biopsies of alpha-fetoprotein (AFP) standard solutions and subject serums, molecular concentration was analyzed from saturation magnetization by the soft type of Fe3O4 MPs with AFP bioprobe coating. In the phantom mixture simulated as bounded MPs in tissue, the bounded MPs was evaluated from the area of the hysteresis loop by hard type of cobalt MPs without bio-probes coating. Not only a calibration curve was founded for many hepatic cell carcinoma stages, but also microscale images verified the Ms increase due to magnetic protein clusters, etc. Hence, its wide populations in clinics could be expected.

Abstract Background Osteoarthritis (OA) and rheumatoid arthritis (RA) are common joint disorders that are considered to be different diseases due to their unique molecular mechanisms and pathogenesis. Chemokines and their corresponding receptors have been well characterized in RA progression, but less so in OA pathogenesis. Methods The human primary synovial fibroblasts (SFs) were obtained from human OA and RA tissue samples. The Western blot and qPCR were performed to analyze the expression levels of CXCL1, as well as CXCL-promoted IL-6 expression in both OASFs and RASFs. The signal cascades that mediate the CXCL1-promoted IL-6 expression were identified by using chemical inhibitors, siRNAs, and shRNAs. Results Here, we found that both diseases feature elevated levels of CXCL1 and interleukin (IL)-6, an important proinflammatory cytokine that participates in OA and RA pathogenesis. In OASFs and RASFs, CXCL1 promoted IL-6 expression in a dose- and time-dependent manner. In OASFs and RASFs overexpressing CXCL1 or transduced with shRNA plasmid, IL-6 expression was markedly upregulated. CXCR2, c-Raf, and MAPKs were found to regulate CXCL1-induced IL-6 expression in OASFs and RASFs. Finally, CXCL1 triggered the transcriptional activities of c-Jun (which regulates the expression of proinflammatory proteins) in OASFs and RASFs. Conclusions Our present work suggests that the CXCL1/CXCR2 axis helps to orchestrate inflammatory responses in OA and RA SFs.

Osteosarcoma, a common aggressive and malignant cancer, appears in the musculoskeletal system among young adults. The major cause of mortality in osteosarcoma was the recurrence of lung metastases. However, the molecular mechanisms of metastasis involved in osteosarcomas remain unclear. Recently, CXCL1 and CXCR2 have been crucial indicators for lung metastasis in osteosarcoma by paracrine releases, suggesting the involvement of directing neutrophils into tumor microenvironment. In this study, overexpression of CXCL1 has a positive correlation with the migratory and invasive activities in osteosarcoma cell lines. Furthermore, the signaling pathway, CXCR2/FAK/PI3K/Akt, is activated through CXCL1 by promoting vascular cell adhesion molecule 1 (VCAM-1) via upregulation of nuclear factor-kappa B (NF-κB) expression and nuclear translocation. The in vivo animal model further demonstrated that CXCL1 serves as a critical promoter in osteosarcoma metastasis to the lung. The correlated expression of CXCL1 and VCAM-1 was observed in the immunohistochemistry staining from human osteosarcoma specimens. Our findings demonstrate the cascade mechanism regulating the network in lung metastasis osteosarcoma, therefore indicating that the CXCL1/CXCR2 pathway is a worthwhile candidate to further develop treatment schemas.

Prostate cancer commonly affects the urinary tract of men and metastatic prostate cancer has a very low survival rate. Apelin belongs to the family of adipokines and is associated with cancer development and metastasis. However, the effects of apelin in prostate cancer metastasis is undetermined. Analysis of the database revealed a positive correlation between apelin level with the progression and metastasis of prostate cancer patients. Apelin treatment facilitates cell migration and invasion through inhibiting tissue inhibitor of metalloproteinase 2 (TIMP2) expression. The increasing miR-106a-5p synthesis via c-Src/PI3K/Akt signaling pathway is controlled in apelin-regulated TIMP2 production and cell motility. Importantly, apelin blockade inhibits prostate cancer metastasis in the orthotopic mouse model. Thus, apelin is a promising therapeutic target for curing metastatic prostate cancer.

Ablation is a clinical cancer treatment, but some demands are still unsatisfied, such as electromagnetic interferences amongst multiple ablation needles during large tumour treatments. This work proposes a physical synthesis for composite particles of biocompatible iron oxide particles and liquid metal gallium (Ga) with different alternative-current (AC)-magnetic-field-induced heat mechanisms of magnetic particle hyperthermia and superior resistance heat. By some imaging, X-ray diffraction, and vibrating sample magnetometer, utilised composite particles were clearly identified as the cluster of few iron oxides using the small weight ratio of high-viscosity liquid metal Ga as conjugation materials without surfactants for physical targeting of limited fluidity. Hence, well penetration inside the tissue and the promotion rate of heat generation to fit the ablation requirement of at least 60 °C in a few seconds are achieved. For the injection and the post-injection magnetic ablations, the volume variation ratios of mice dorsal tumours on Day 12 were expressed at around one without tumour growth. Its future powerful potentiality is expected through a percutaneous injection.

Osteosarcoma, a primary bone tumor, responds poorly to chemotherapy and radiation therapy in children and young adults; hence, as the basis for an alternative treatment, this study investigated the cytotoxic and antiproliferative effects of naringenin on osteosarcoma cell lines, HOS and U2OS, by using cell counting kit-8 and colony formation assays. DNA fragmentation and the increase in the G2/M phase in HOS and U2OS cells upon treatment with various naringenin concentrations were determined by using the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay and Annexin V/propidium iodide double staining, respectively. Flow cytometry was performed, and 2′,7′-dichlorodihydrofluorescein diacetate, JC-1, and Fluo-4 AM ester probes were examined for reactive oxygen species (ROS) generation, mitochondrial membrane potential, and intracellular calcium levels, respectively. Caspase activation, cell cycle, cytosolic and mitochondrial, and autophagy-related proteins were determined using western blotting. The results indicated that naringenin significantly inhibited viability and proliferation of osteosarcoma cells in a dose-dependent manner. In addition, naringenin induced cell cycle arrest in osteosarcoma cells by inhibiting cyclin B1 and cyclin-dependent kinase 1 expression and upregulating p21 expression. Furthermore, naringenin significantly inhibited the growth of osteosarcoma cells by increasing the intracellular ROS level. Naringenin induced endoplasmic reticulum (ER) stress-mediated apoptosis through the upregulation of ER stress markers, GRP78 and GRP94. Naringenin caused acidic vesicular organelle formation and increased autophagolysosomes, microtubule-associated protein-light chain 3-II protein levels, and autophagy. The findings suggest that the induction of cell apoptosis, cell cycle arrest, and autophagy by naringenin through mitochondrial dysfunction, ROS production, and ER stress signaling pathways contribute to the antiproliferative effect of naringenin on osteosarcoma cells.

Abstract Background Osteoarthritis (OA) is a degenerative joint disease that affects the cartilage, synovium, and subchondral bone and is the leading cause of disability in older populations. Specific diagnostic biomarkers are lacking; hence, treatment options for OA are limited. Synovial inflammation is very common in OA joints and has been associated with both OA’s symptoms and pathogenesis. Confirming the role of the synovium in OA pathogenesis is a promising strategy for mitigating the symptoms and progression of OA. CX3CL1 is the only member of the CX3C class of chemokines that combines the properties of chemoattractants and adhesion molecules. CX3CL1 levels in the synovium and serum were both discovered to be positively associated with OA pathogenesis. CX3CL1 and its receptor CX3CR1 belong to a family of G protein-coupled receptors. Matrix metalloproteinases (MMPs), which are responsible for matrix degradation, play a crucial role in OA progression. The relationship between CX3CL1 and MMPs in the pathophysiology of OA is still unclear. Methods CX3CL1-induced MMP-3 production was assessed with quantitative real-time PCR and ELISA. The mechanisms of action of CX3CL1 in different signaling pathways were studied using western blot analysis, quantitative real-time PCR and ELISA. Neutralization antibodies of integrin were achieved to block the CX3CR1 signaling pathway. Luciferase assays were used to study NF-κB promoter activity. Results We investigated the signaling pathway involved in CX3CL1-induced MMP-3 production in osteoarthritis synovial fibroblasts (OASFs). CX3CL1 was found to induce MMP-3 production in a concentration-dependent and time-dependent manner. Using pharmacological inhibitors and CX3CR1 small interfering RNA to block CX3CR1 revealed that the CX3CR1 receptor was involved in the CX3CL1-mediated upregulation of MMP-3. CX3CL1-mediated MMP-3 production was attenuated by c-Raf inhibitors (GW5074) and MEK/ERK inhibitors (PD98059 and U0126). The OASFs were stimulated using CX3CL1-activated p65 phosphorylation. Conclusions Our results demonstrate that CX3CL1 activates c-Raf, MEK, ERK, and NF-κB on the MMP-3 promoter through CX3CR1, thus contributing to cartilage destruction during OA.

Chondrosarcoma is a malignant bone tumor that is characterized by high metastatic potential and marked resistance to radiation and chemotherapy. The knowledge that adipokines facilitate the initiation, progression, metastasis, and treatment resistance of various tumors has driven several in vitro and in vivo investigations into the effects of adipokines resistin, leptin, and adiponectin upon the development and progression of chondrosarcomas. Another adipokine, visfatin, is known to regulate tumor progression and metastasis, although how this molecule may affect chondrosarcoma metastasis is unclear. Here, we found that visfatin facilitated cellular migration via matrix metalloproteinase-2 (MMP-2) production in human chondrosarcoma cells and overexpression of visfatin enhanced lung metastasis in a mouse model of chondrosarcoma. Visfatin-induced stimulation of MMP-2 synthesis and activation of the AP-1 transcription factor facilitated chondrosarcoma cell migration via the ERK, p38, and JNK signaling pathways. This evidence suggests that visfatin is worth targeting in the treatment of metastatic chondrosarcoma.

A chondrosarcoma is a common tumor of the soft tissue and bone that has a high propensity to metastasize to distant organs. Nerve growth factor (NGF) is capable of promoting the progression and metastasis of several different types of tumors although the effects of NGF in a chondrosarcoma are not confirmed. Here, we found that the levels of NGF and matrix metalloproteinase-2 (MMP-2) correlated with the tumor stage in patients with a chondrosarcoma. NGF facilitated the MMP-2-dependent cellular migration in human chondrosarcoma JJ012 cells while the overexpression of NGF enhanced the lung metastasis in a mouse model of a chondrosarcoma. NGF promoted the MMP-2 synthesis and cell migration by inhibiting miR-423-5p expression through the FAK and c-Src signaling cascades. NGF appears to be a worthwhile therapeutic target in the treatment of a metastatic chondrosarcoma.

Osteosarcoma is the most common primary tumor of the skeletal system and is well-known to have an aggressive clinical outcome and high metastatic potential. The chemokine (C-X-C motif) ligand 13 (CXCL13) plays a vital role in the development of several cancers. However, the effect of CXCL13 in the motility of osteosarcoma cells remains uncertain. Here, we found that CXCL13 increases the migration and invasion potential of three osteosarcoma cell lines. In addition, CXCL13 expression was upregulated in migration-prone MG-63 cells. Vascular cell adhesion molecule 1 (VCAM-1) siRNA and antibody demonstrated that CXCL13 promotes migration via increasing VCAM-1 production. We also show that CXCR5 receptor controls CXCL13-mediated VCAM-1 expression and cell migration. Our study identified that CXCL13/CXCR5 axis facilitate VCAM-1 production and cell migration in human osteosarcoma via the phospholipase C beta (PLCβ), protein kinase C α (PKCα), c-Src, and nuclear factor-κB (NF-κB) signaling pathways. CXCL13 and CXCR5 appear to be a novel therapeutic target in metastatic osteosarcoma.

Background: Rheumatoid arthritis (RA) has been associated with air pollution, possibly due to the augmentation of inflammatory effects. In this study, we aimed to determine the roles of inflammatory pathways and microRNA involved in the pathogenesis of RA fibroblast-like synoviocytes (FLS) inflammation induced by particulate matter. Methods: The inflammatory mediators, messenger RNAs, microRNAs and their interrelationships were investigated using western blotting, QPCR, ELISA and immunohistochemistry. Results: Particulate matter (PMs) induced an increase in the expression of interleukin-6 (IL-6) and cyclooxygenase-II (COX-II) in RA-FLS and microRNA-137 was found definitely to mediate the inflammatory pathways. PMs-induced generation of reactive oxygen species (ROS) in RA-FLS was attenuated by pretreatment with antioxidants. Nox-dependent ROS generation led to phosphorylation of ERK1/2, p38 and JNK, followed by downregulation of microRNA-137. In vivo studies, the joints of rats exposed to PMs revealed synovial fibroblast inflammation under pathologic examination and the expressions of IL-6 and COX-II were obviously increased. PMs exposure results in activated ROS-mediated mitogen-activated protein kinase (MAPK) signaling pathways and cause increased IL-6 and COX-II through downregulation of hsa-miRNA-137, which lead to inflammation and RA exacerbation. Conclusions: microRNA-137 plays an important role in PMs-induced RA acute exacerbation through MAPK signaling pathways and IL-6/COX-II activation. Targeting these mechanisms can potentially be used to develop new therapeutic strategies and prevention of RA inflammation in the future.

Osteosarcoma, the most common of all bone malignancies, has a high likelihood of lung metastasis. Up until now, the molecular mechanisms involved in osteosarcomas with lung metastases are not clearly understood. Recent observations have shown that the chemokine CXCL1 and its receptor CXCR2 assist with the homing of neutrophils into the tumor microenvironment. Here, we show that the CXCL1/CXCR2 paracrine axis is crucial for lung metastasis in osteosarcoma. In an in vivo lung metastasis model of osteosarcoma, lung blood vessels expressed CXCL1 and osteosarcoma cells expressed the CXCR2 receptor. CXCR2 expression was higher in osteosarcoma cell lines than in normal osteoblast cells. Immunohistochemistry staining of clinical osteosarcoma specimens revealed positive correlations between CXCR2 expression and pathology stage and also vascular cell adhesion molecule 1 (VCAM-1) expression. High levels of CXCL1 secreted by human pulmonary artery endothelial cells (HPAECs) promoted osteosarcoma cell mobility, which was mediated by the upregulation of VCAM-1 expression. When HPAECs-conditioned media was incubated in osteosarcoma cells, we observed that the CXCR2 receptor and FAK/PI3K/Akt/NF-κB signaling cascade were required for VCAM-1 expression. Our findings illustrate a molecular mechanism of lung metastasis in osteosarcoma and indicate that CXCL1/CXCR2 is worth targeting in treatment schemas.

Glioblastoma multiforme (GBM) is an extremely aggressive and devastating malignant tumor in the central nervous system. Its incidence is increasing and the prognosis is poor. Artocarpin is a natural prenylated flavonoid with various anti-inflammatory and anti-tumor properties. Studies have shown that artocarpin is associated with cell death of primary glioblastoma cells. However, the in vivo effects and the cellular and molecular mechanisms modulating the anticancer activities of artocarpin remain unknown. In this study, we demonstrated that treating the glioblastoma cell lines U87 and U118 cells with artocarpin induced apoptosis. Artocarpin-induced apoptosis is associated with caspase activation and poly (ADP-ribose) polymerase (PARP) cleavage and is mediated by the mitochondrial pathway. This is associated with mitochondrial depolarization, mitochondrial-derived reactive oxidative species (ROS) production, cytochrome c release, Bad and Bax upregulations, and Bcl-2 downregulation. Artocarpin induced NADPH oxidase/ROS generation plays an important role in the mitochondrial pathway activation. Furthermore, we found artocarpin-induced ROS production in mitochondria is associated with Akt- and ERK1/2 activation. After treatment with artocarpin, ROS causes PI3K/Akt/ERK1/2-induced cell death of these tumor cells. These observations were further verified by the results from the implantation of both U87 and U118 cells into in vivo mouse. In conclusion, our findings suggest that artocarpin induces mitochondria-associated apoptosis of glioma cells, suggesting that artocarpine can be a potential chemotherapeutic agent for future GBM treatment.

Osteosarcoma (OS) is a primary malignant tumor of bone and is most prevalent in children and adolescents. OS is frequently associated with pulmonary metastasis, which is the main cause of OS-related mortality. OS has a poor prognosis and is often unresponsive to conventional chemotherapy. In this study, we determined that Nimbolide, a novel anti-cancer therapy, acts by modulating multiple mechanisms in osteosarcoma cells. Nimbolide induces apoptosis by increasing endoplasmic reticulum (ER) stress, mitochondrial dysfunction, accumulation of reactive oxygen species (ROS), and finally, caspase activation. We also determined that Nimbolide inhibits cell migration, which is crucial for metastasis, by reducing the expression of integrin αvβ5. In addition, our results demonstrate that integrin αvβ5 expression is modulated by the PI3K/Akt and NF-κB signaling cascade. Nimbolide has potential as an anti-tumor drug given its multifunctional effects in OS. Collectively, these results help us to understand the mechanisms of action of Nimbolide and will aid in the development of effective therapies for OS.

Osteosarcoma (OS) is a relatively rare form of cancer, but OS is the most commonly diagnosed bone cancer in children and adolescents. Chemotherapy has side effects and induces drug resistance in OS. Since an effective adjuvant therapy was insufficient for treating OS, researching novel and adequate remedies is critical. Hyperthermia can induce cell death in various cancer cells, and thus, in this study, we investigated the anticancer method of hyperthermia in human OS (U-2 OS) cells. Treatment at 43 °C for 60 min induced apoptosis in human OS cell lines, but not in primary bone cells. Furthermore, hyperthermia was associated with increases of intracellular reactive oxygen species (ROS) and caspase-3 activation in U-2 OS cells. Mitochondrial dysfunction was followed by the release of cytochrome c from the mitochondria, and was accompanied by decreased anti-apoptotic Bcl-2 and Bcl-xL, and increased pro-apoptotic proteins Bak and Bax. Hyperthermia triggered endoplasmic reticulum (ER) stress, which was characterized by changes in cytosolic calcium levels, as well as increased calpain expression and activity. In addition, cells treated with calcium chelator (BAPTA-AM) blocked hyperthermia-induced cell apoptosis in U-2 OS cells. In conclusion, hyperthermia induced cell apoptosis substantially via the ROS, ER stress, mitochondria, and caspase pathways. Thus, hyperthermia may be a novel anticancer method for treating OS.

CCN3, otherwise known as the nephroblastoma overexpressed (NOV) protein, is a cysteine-rich protein that belongs to the CCN family and regulates several cellular functions. Osteoblasts are major bone-forming cells that undergo proliferation, mineralization, renewal, and repair during the bone formation process. We have previously reported that CCN3 increases bone morphogenetic protein 4 (BMP-4) production and bone mineralization in osteoblasts, although the role of CCN3 remains unclear with regard to osteogenic transcription factors (runt-related transcription factor 2 (Runx2) and osterix). Here, we used alizarin red-S and alkaline phosphatase staining to show that CCN3 enhances osteoblast differentiation. Stimulation of osteoblasts with CCN3 increases expression of osteogenic factors such as BMPs, Runx2, and osterix. Moreover, we found that the inhibition of miR-608 expression is involved in the effects of CCN3 and that incubation of osteoblasts with CCN3 promotes focal adhesion kinase (FAK) and Akt phosphorylation. Our results indicate that CCN3 promotes the expression of Runx2 and osterix in osteoblasts by inhibiting miR-608 expression via the FAK and Akt signaling pathways.

In this study, we investigated the anticancer effects of a new benzimidazole derivative, 1-benzyl-2-phenyl -benzimidazole (BPB), in human chondrosarcoma cells. BPB-mediated apoptosis was assessed by the MTT assay and flow cytometry analysis. The in vivo efficacy was examined in a JJ012 xenograft model. Here we found that BPB induced apoptosis in human chondrosarcoma cell lines (JJ012 and SW1353) but not in primary chondrocytes. BPB induced upregulation of Bax, Bad and Bak, downregulation of Bcl-2, Bid and Bcl-XL and dysfunction of mitochondria in chondrosarcoma. In addition, BPB also promoted cytosolic releases AIF and Endo G. Furthermore, it triggered extrinsic death receptor-dependent pathway, which was characterized by activating Fas, FADD and caspase-8. Most importantly, animal studies revealed a dramatic 40% reduction in tumor volume after 21 days of treatment. Thus, BPB may be a novel anticancer agent for the treatment of chondrosarcoma.

Osteoarthritis (OA) belongs to a group of degenerative diseases. Synovial inflammation, cartilage abrasion, and subchondral sclerosis are characteristics of OA. Researchers do not fully understand the exact etiology of OA. However, matrix metalloproteinases (MMPs), which are responsible for cartilage matrix degradation, play a pivotal role in the progression of OA. Amphiregulin (AREG) binds to the EGF receptor (EGFR) and activates downstream proteins. AREG is involved in a variety of pathological processes, such as the development of tumors, inflammatory diseases, and rheumatoid arthritis. However, the relationship between AREG and MMP-13 in OA synovial fibroblasts (SFs) remains unclear. We investigated the signaling pathway involved in AREG-induced MMP-13 production in SFs. AREG caused MMP-13 production in a concentration- and time-dependent manner. The results of using pharmacological inhibitors and EGFR siRNA to block EGFR revealed that the EGFR receptor was involved in the AREG-mediated upregulation of MMP-13. AREG-mediated MMP-13 production was attenuated by PI3K and Akt inhibitors. The stimulation of cells by using AREG activated p65 phosphorylation and p65 translocation from the cytosol to the nucleus. Our results provide evidence that AREG acts through the EGFR and activates PI3K, Akt, and finally NF-kappaB on the MMP-13 promoter, thus contributing to cartilage destruction during osteoarthritis.

Chondrosarcoma is a highly malignant cartilage-forming bone tumor that has the capacity to invade locally and cause distant metastasis. Moreover, chondrosarcoma is intrinsically resistant to conventional chemotherapy or radiotherapy. The novel benzofuran derivative, BL-038 (2-amino-3-(2,6-dichlorophenyl)-6-(4-methoxyphenyl)benzofuran-4-yl acetate), has been evaluated for its anticancer effects in human chondrosarcoma cells. BL-038 caused cell apoptosis in two human chondrosarcoma cell lines, JJ012 and SW1353, but not in primary chondrocytes. Treatment of chondrosarcoma with BL-038 also induced reactive oxygen species (ROS) production. Furthermore, BL-038 decreased mitochondrial membrane potential (MMP) and changed mitochondrial-related apoptosis, by downregulating the anti-apoptotic activity members (Bcl-2, Bcl-xL) and upregulating pro-apoptotic members (Bax, Bak) of the B-cell lymphoma 2 (Bcl-2) family of proteins, key regulators of the apoptotic machinery in cells. These results demonstrate that in human chondrosarcoma cells, the apoptotic and cytotoxic effects of BL-038 are mediated by the intrinsic mitochondria-mediated apoptotic pathway, which in turn causes the release of cytochrome c, the activation of caspase-9 and caspase-3, and the cleavage of poly (ADP-ribose) polymerase (PARP), to elicit apoptosis response. Our results show that the benzofuran derivative BL-038 induces apoptosis in chondrosarcoma cells.

Several diseases have been linked to particulate matter (PM) exposure. Outdoor activities, such as road running or jogging, are popular aerobic exercises due to few participatory limitations. Osteoarthritis (OA) is a progressive degenerative joint disease, usually observed at age 40, and not noticed before pain or diagnosis. Although exercise has health benefits, it is unclear whether outdoor jogging in higher PM (standard reference material 1649b, SRM 1649b) concentration environments could affect OA development or severity. Hence, a PM exposure monosodium iodoacetate (MIA)-induced OA animal jogged model was established for investigation. Results showed that high doses of PM (5 mg) significantly increased pro-inflammatory factors such as tumor necrosis factor a (TNF-a), interleukin (IL)-1ß, and IL-6, and M1 macrophages in the lung region, also obtained in systemic IL-6 and TNF-a expressions in this MIA-OA rat model. Moreover, levels of osteocalcin, cartilage oligomeric matrix protein (COMP), and N-telopeptides of type I collagen were especially influenced in MIA+PM groups. Morphological and structural changes of the knee joint were detected by micro-computed tomography images (micro-CT) and immunohistochemistry. MIA + PM rats exhibited severe bone density decrease, cartilage wear, and structure damages, accompanied by lower levels of physical activity, than the sham group and groups receiving MIA or PM alone. The findings suggest that the severity of OA could be promoted by PM exposure with a PM concentration effect via systemic inflammatory mechanisms. To the best of our knowledge, this is the first study to provide direct effects of PM exposure on OA severity. [ABSTRACT FROM AUTHOR]

Osteosarcoma is the most common primary bone tumor that occurs in children and adolescents. Osteosarcoma has a poor prognosis and is often unresponsive to chemotherapy. Therefore, it remains a challenge to identify a novel strategy to effectively treat osteosarcoma. The present study demonstrated a novel opportunity in osteosarcoma treatment using the natural compound plumbagin. Plumbagin reduced cell viability in osteosarcoma cells but not normal bone cells, as determined by MTT assay and colony formation assay. Plumbagin induced cell apoptosis by mitochondrial dysfunction, which in turn promoted Ca2+ release and endoplasmic reticulum (ER)‑stress, as determined by DAPI staining assay, DNA fragmentation assay, flow cytometry and western blotting analysis. In addition, plumbagin improved reactive oxygen species (ROS) generation, as determined by flow cytometry. Finally, these apoptotic cascades activated caspase‑3 and caspase‑9 to elicit apoptosis response. Our results demonstrated the anticancer effect of plumbagin by inducing cell apoptosis in osteosarcoma cells. In conclusion, plumbagin activated the apoptosis signaling pathway through eliciting ROS, ER stress, mitochondria dysfunction, and finally causing caspase activation. These results indicated that plumbagin may serve as potential antitumor drug by its multifunctional effects in osteosarcoma. [ABSTRACT FROM AUTHOR]

Background: Osteosarcoma is the most common primary malignant tumor in children and young adults, and its treatment requires effective therapeutic approaches because of a high mortality rate for lung metastasis. Epithelial to mesenchymal transition (EMT) has received considerable attention as a conceptual paradigm for explaining the invasive and metastatic behavior during cancer progression. The cysteine-rich angiogenic inducer 61 (Cyr61) gene, a member of the CCN gene family, is responsible for the secretion of Cyr61, a matrix-associated protein that is involved in several cellular functions. A previous study showed that Cyr61 expression is related to osteosarcoma progression. In addition, Cyr61 could promote cell migration and metastasis in osteosarcoma. However, discussions on the molecular mechanism involved in Cyr61-regulated metastasis in osteosarcoma is poorly discussed. Results: We determined that the expression level of Cyr61 induced cell migration ability in osteosarcoma cells. The Cyr61 protein promoted the mesenchymal transition of osteosarcoma cells by upregulating mesenchymal markers (TWIST-1 and N-cadherin) and inhibiting the epithelial marker (E-cadherin). Moreover, the Cyr61-induced cell migration was mediated by EMT. The Cyr61 protein elicited a signaling cascade that included αvβ5 integrin, Raf-1, mitogen-activated protein kinase (MEK), extracellular signal-regulated kinase (ERK), and Elk-1. The reagent or gene knockdown of these signaling proteins could inhibit Cyr61-promoted EMT in osteosarcoma. Finally, the knockdown of Cyr61 expression obviously inhibited cell migration and repressed mesenchymal phenotypes, reducing lung metastasis. Conclusion: Our results indicate that Cyr61 promotes the EMT of osteosarcoma cells by regulating EMT markers via a signal transduction pathway that involves αvβ5 integrin, Raf-1, MEK, ERK, and Elk-1. [ABSTRACT FROM AUTHOR]

Background: Cyclooxygenase (COX)-2, the inducible isoform of prostaglandin (PG) synthase, has been implicated in tumor metastasis. Interaction of COX-2 with its specific EP receptors on the surface of cancer cells has been reported to induce cancer invasion. However, the effects of COX-2 on migration activity in human chondrosarcoma cells are mostly unknown. In this study, we examined whether COX-2 and EP interaction are involved in metastasis of human chondrosarcoma. Results: We found that over-expression of COX-2 or exogenous PGE2 increased the migration of human chondrosarcoma cells. We also found that human chondrosarcoma tissues and chondrosarcoma cell lines had significant expression of the COX-2 which was higher than that in normal cartilage. By using pharmacological inhibitors or activators or genetic inhibition by the EP receptors, we discovered that the EP1 receptor but not other PGE receptors is involved in PGE2-mediated cell migration and α2β1 integrin expression. Furthermore, we found that human chondrosarcoma tissues expressed a higher level of EP1 receptor than normal cartilage. PGE2-mediated migration and integrin up-regulation were attenuated by phospholipase C (PLC), protein kinase C (PKC) and c-Src inhibitor. Activation of the PLCβ, PKCα, c-Src and NF-κB signaling pathway after PGE2 treatment was demonstrated, and PGE2-induced expression of integrin and migration activity were inhibited by the specific inhibitor, siRNA and mutants of PLC, PKC, c-Src and NF-κB cascades. Conclusions: Our results indicated that PGE2 enhances the migration of chondrosarcoma cells by increasing α2β1 integrin expression through the EP1/PLC/PKCα/c-Src/NF-κB signal transduction pathway. [ABSTRACT FROM AUTHOR]

We previously showed that the rat dipeptidyl peptidase IV (rDPP IV) monoclonal antibody (mAb) 6A3 greatly inhibits the pericellular polymeric fibronectin-mediated metastatic cancer cell adhesion to rDPP IV. L311QWLRRI in rDPP IV has been proposed as the putative fibronectin-binding site. However, the inhibitory mechanism of 6A3 has been elusive. Epitope mapping of 6A3 may help to understand the interaction between fibronectin and rDPP IV. In the present study, we showed that 6A3 species-specifically recognized rDPP IV but inhibited fibronectin/rDPP IV-mediated cell adhesions of various cancer types and species, which was independent of rDPP IV enzymatic activity. The 6A3 epitope was stably exposed in both native and denatured rDPP IV. On the basis of the resolved structures and the species variations in DPP IV sequences, we finely mapped the 6A3 epitope to a surface-exposed Thr331-dependent motif D329KTTLVWN, only 11 amino acids away from L311QWLRRI on the same plane as the fifth β-propeller blade. The functionality of 6A3 epitope in rDPP IV was ultimately demonstrated by the ability of 6A3-recognizable fragments to interfere with the inhibitory effect of 6A3 on full-length rDPP IV binding to pericellular polymeric fibronectin. On the basis of structural analysis, and the fact that the preformed fibronectin fragment/rDPP IV complex was co-immunoprecipitated by 6A3 and fixing the rDPP IV structure with paraformaldehyde did not avert the inhibitory effect, the mechanism of 6A3 inhibition may not be the result of complete competition or conformational change. Structured digital abstract • : DppIV (uniprotkb: ) binds ( ) to FNIII14 (uniprotkb: ) by anti bait coimmunoprecipitation ( ) [ABSTRACT FROM AUTHOR]