MicroRNA-631 Resensitizes Doxorubicin-Resistant Chondrosarcoma Cells by Targeting Apelin.

Chondrosarcoma is the second most common type of bone cancer. Surgical resection is the best choice for clinical treatment. High-grade chondrosarcoma is destructive and is more possible to metastasis, which is difficult to remove using surgery. Doxorubicin (Dox) is the most commonly used chemotherapy drug in the clinical setting; however, drug resistance is a major obstacle to effective treatment. In the present study, we compared Dox-resistant SW1353 cells to their parental cells using RNA sequencing (RNA-Seq). We found that the apelin (APLN) pathway was highly activated in resistant cells. In addition, tissue array analysis also showed that APLN was higher in high-grade tissues compared to low-grade tissues. APLN is a member of the adipokine family, which is a novel secreted peptide with multifunctional and biological activities. Previously, studies have shown that inhibition of the APLN axis may have a therapeutic benefit in cancers. However, the role of APLN in chondrosarcoma is completely unclear, and no related studies have been reported. During in vitro experiments, APLN was also observed to be highly expressed and secreted in Dox-resistant cells. Once APLN was knocked down, it could effectively improve its sensitivity to Dox. We also explored possible upstream regulatory microRNAs (miRNAs) of APLN through bioinformatics tools and the results disclosed that miR-631 was the most likely regulator of APLN. Furthermore, the expression of miR-631 was lower in the resistant cells, but overexpression of miR-631 in the Dox-resistant cell lines significantly increased the Dox sensitivity. These results were also observed in another chondrosarcoma cell line, JJ012 cells. Taken together, these findings will provide rationale for the development of drug resistance biomarkers and therapeutic strategies for APLN pathway inhibitors to improve the survival of patients with chondrosarcoma.

ADAM17 Confers Temozolomide Resistance in Human Glioblastoma Cells and miR-145 Regulates Its Expression.

Glioblastoma (GBM) is a malignant brain tumor, commonly treated with temozolomide (TMZ). Upregulation of A disintegrin and metalloproteinases (ADAMs) is correlated to malignancy; however, whether ADAMs modulate TMZ sensitivity in GBM cells remains unclear. To explore the role of ADAMs in TMZ resistance, we analyzed changes in ADAM expression following TMZ treatment using RNA sequencing and noted that ADAM17 was markedly upregulated. Hence, we established TMZ-resistant cell lines to elucidate the role of ADAM17. Furthermore, we evaluated the impact of ADAM17 knockdown on TMZ sensitivity in vitro and in vivo. Moreover, we predicted microRNAs upstream of ADAM17 and transfected miRNA mimics into cells to verify their effects on TMZ sensitivity. Additionally, the clinical significance of ADAM17 and miRNAs in GBM was analyzed. ADAM17 was upregulated in GBM cells under serum starvation and TMZ treatment and was overexpressed in TMZ-resistant cells. In in vitro and in vivo models, ADAM17 knockdown conferred greater TMZ sensitivity. miR-145 overexpression suppressed ADAM17 and sensitized cells to TMZ. ADAM17 upregulation and miR-145 downregulation in clinical specimens are associated with disease progression and poor prognosis. Thus, miR-145 enhances TMZ sensitivity by inhibiting ADAM17. These findings offer insights into the development of therapeutic approaches to overcome TMZ resistance.

The inhibitory effects of PGG and EGCG against the SARS-CoV-2 3C-like protease.

The coronavirus disease (COVID-19) pandemic, resulting from human-to-human transmission of a novel severe acute respiratory syndrome coronavirus (SARS-CoV-2), has led to a global health crisis. Given that the 3 chymotrypsin-like protease (3CLpro) of SARS-CoV-2 plays an indispensable role in viral polyprotein processing, its successful inhibition halts viral replication and thus constrains virus spread. Therefore, developing an effective SARS-CoV-2 3CLpro inhibitor to treat COVID-19 is imperative. A fluorescence resonance energy transfer (FRET)-based method was used to assess the proteolytic activity of SARS-CoV-2 3CLpro using intramolecularly quenched fluorogenic peptide substrates corresponding to the cleavage sequence of SARS-CoV-2 3CLpro. Molecular modeling with GEMDOCK was used to simulate the molecular interactions between drugs and the binding pocket of SARS-CoV-2 3CLpro. This study revealed that the Vmax of SARS-CoV-2 3CLpro was about 2-fold higher than that of SARS-CoV 3CLpro. Interestingly, the proteolytic activity of SARS-CoV-2 3CLpro is slightly more efficient than that of SARS-CoV 3CLpro. Meanwhile, natural compounds PGG and EGCG showed remarkable inhibitory activity against SARS-CoV-2 3CLpro than against SARS-CoV 3CLpro. In molecular docking, PGG and EGCG strongly interacted with the substrate binding pocket of SARS-CoV-2 3CLpro, forming hydrogen bonds with multiple residues, including the catalytic residues C145 and H41. The activities of PGG and EGCG against SARS-CoV-2 3CLpro demonstrate their inhibition of viral protease activity and highlight their therapeutic potentials for treating SARS-CoV-2 infection.

Identification of a novel interaction site between the large hepatitis delta antigen and clathrin that regulates the assembly of genotype III hepatitis delta virus.

BACKGROUND: Hepatitis delta virus (HDV), a satellite virus of hepatitis B virus (HBV), is a small, defective RNA virus strongly associated with the most severe form of hepatitis and progressive chronic liver disease and cirrhosis. Chronic hepatitis D, resulting from HBV/HDV coinfection, is considered to be the most severe form of viral hepatitis and affects 12-20 million people worldwide. Involved in the endocytosis and exocytosis of cellular and viral proteins, clathrin contributes to the pathogenesis and morphogenesis of HDV. Previously, we demonstrated that HDV-I and -II large hepatitis delta antigens (HDAg-L) possess a putative clathrin box that interacts with clathrin heavy chain (CHC) and supports HDV assembly. METHODS: Virus assembly and vesicular trafficking of HDV virus-like particles (VLPs) were evaluated in Huh7 cells expressing HDV-I, -II and -III HDAg-L and hepatitis B surface antigen (HBsAg). To elucidate the interaction motif between HDAg-L and CHC, site-directed mutagenesis was performed to introduce mutations into HDAg-L and CHC and analyzed using coimmunoprecipitation or pull-down assays. RESULTS: Comparable to HDV-I virus-like particles (VLPs), HDV-III VLPs were produced at a similar level and secreted into the medium via clathrin-mediated post-Golgi vesicular trafficking. Mutation at F27 or E33 of CHC abolished the binding of CHC to the C-terminus of HDV-III HDAg-L. Mutation at W207 of HDV-III HDAg-L inhibited its association with CHC and interfered with HDV-III VLP formation. We elucidated mechanism of the binding of HDV-III HDAg-L to CHC and confirmed the pivotal role of clathrin binding in the assembly of genotype III HDV. CONCLUSIONS: A novel W box which was identified at the C terminus of HDV-III HDAg-L is known to differ from the conventional clathrin box but also interacts with CHC. The novel W box of HDAg-L constitutes a new molecular target for anti-HDV-III therapeutics.

The Clinical Application of Pulsed Radiofrequency Induces Inflammatory Pain via MAPKs Activation: A Novel Hint for Pulsed Radiofrequency Treatment.

Pulsed radiofrequency (PRF) works by delivering short bursts of radiofrequency to a target nerve, thereby affecting nerve signal transduction to reduce pain. Although preliminary clinical investigations have shown that PRF treatment can be used safely as an alternative interventional treatment in patients with refractory pain conditions, unexpected damage to a normal nerve/ganglion is still one of the possible complications of using the PRF strategy. Noxious pain may also be triggered if PRF treatment accidentally damages an intact nerve. However, few studies in the literature have described the intracellular modifications that occur in neuronal cells after PRF stimulation. Therefore, in this study, we evaluated the effects of PRF on unimpaired nerve function and investigated the potential mechanisms of PRF-induced pain. Wistar rats were stimulated with 30-60 V of PRF for 6 min, and mechanical allodynia, cold hypersensitivity, cytokine and matrix metalloproteinase (MMP) production, and mitogen-activated protein kinase activity (p38 MAPK, ERK1/2, JNK/SAPK) were analyzed. The results indicated that PRF stimulation induced a significant algesic effect and nociceptive response. In addition, the protein array and Western blotting analyses showed that the clinical application of 60 V of PRF can induce the activation of MAPKs and the production of inflammatory cytokines and MMPs in the lumbar dorsal horn, which is necessary for nerve inflammation, and it can be suppressed by MAPK antagonist treatment. These results indicate that PRF stimulation may induce inflammation of the intact nerve, which in turn causes inflammatory pain. This conclusion can also serve as a reminder for PRF treatment of refractory pain.

Basic fibroblast growth factor promotes doxorubicin resistance in chondrosarcoma cells by affecting XRCC5 expression.

Chondrosarcoma is the second most common form of bone cancer and is characterized by its ability to produce an extracellular matrix of the cartilage. High-grade chondrosarcoma is highly aggressive and can metastasize to other parts of the body. Chondrosarcoma is resistant to both conventional chemotherapy and radiotherapy; hence, the current main treatment is still surgical resection. Doxorubicin (Dox) has been shown to significantly improve patient survival compared with untreated chondrosarcoma. However, for patients with metastasis, surgical resection alone can hardly treat them. In addition, drug resistance is one of the leading causes of death in patients with chondrosarcoma. Secreted proteins can mediate cell-cell interactions in the cancer microenvironment, which may be associated with the development of drug resistance. In the present study, chondrosarcoma cells were treated with Dox, the conditioned medium was then collected and changes in secreted proteins were analyzed using the antibody array. Results showed that the Dox-treated group had the highest secretion of basic fibroblast growth factor (bFGF), indicating the effect of bFGF on Dox sensitivity in chondrosarcoma. Furthermore, lentiviral-mediated knockdown and treatment of exogenous recombinant protein were employed to further investigate the effect of bFGF on Dox resistance. Results demonstrated that bFGF can promote the expression of X-ray repair cross-complementing protein 5 (XRCC5), leading to Dox resistance. Secreted bFGF is likely to be detected in serum, in addition to being a biomarker for predicting Dox resistance, the combination of Dox and bFGF/XRCC5 blockers may be a new therapeutic strategy to improve the efficacy of Dox in future.

Valproic acid-induced amphiregulin secretion confers resistance to temozolomide treatment in human glioma cells.

BACKGROUND: Glioblastoma multiforme (GBM) is the most severe type of primary brain tumor with a high mortality rate. Although extensive treatments for GBM, including resection, irradiation, chemotherapy and immunotherapy, have been tried, the prognosis is still poor. Temozolomide (TMZ), an alkylating agent, is a front-line chemotherapeutic drug for the clinical treatment of GBM; however, its effects are very limited because of the chemoresistance. Valproic acid (VPA), an antiepileptic agent with histone deacetylase inhibitor activity, has been shown to have synergistic effects with TMZ against GBM. The mechanism of action of VPA on TMZ combination therapy is still unclear. Accumulating evidence has shown that secreted proteins are responsible for the cross talking among cells in the tumor microenvironment, which may play a critical role in the regulation of drug responses. METHODS: To understand the effect of VPA on secreted proteins in GBM cells, we first used the antibody array to analyze the cell culture supernatant from VPA-treated and untreated GBM cells. The results were further confirmed by lentivirus-mediated knockdown and exogenous recombinant administration. RESULTS: Our results showed that amphiregulin (AR) was highly secreted in VPA-treated cells. Knockdown of AR can sensitize GBM cells to TMZ. Furthermore, pretreatment of exogenous recombinant AR significantly increased EGFR activation and conferred resistance to TMZ. To further verify the effect of AR on TMZ resistance, cells pre-treated with AR neutralizing antibody markedly increased sensitivity to TMZ. In addition, we also observed that the expression of AR was positively correlated with the resistance of TMZ in different GBM cell lines. CONCLUSIONS: The present study aimed to identify the secreted proteins that contribute to the modulation of drug response. Understanding the full set of secreted proteins present in glial cells might help reveal potential therapeutic opportunities. The results indicated that AR may potentially serve as biomarker and therapeutic approach for chemotherapy regimens in GBM.

Amphiregulin enhances cell migration and resistance to doxorubicin in chondrosarcoma cells through the MAPK pathway.

Chondrosarcoma is characterized by the ability to produce extracellular matrix of cartilage. Curative surgical resection becomes difficult when high-grade chondrosarcoma metastasizes to other parts of the body. Doxorubicin (Dox) has been widely used clinically to treat many different types of cancers, including chondrosarcomas. However, chondrosarcoma is often resistant to chemotherapy and radiotherapy. New systemic treatment regimens are needed to improve the prognosis. Amphiregulin (AR) has been reported to be involved in cancer metastasis and drug resistance. The aim of the present study was to investigate the role of AR on cell migration and Dox sensitivity. To gain insight into the mechanisms used by AR to mediate its effects, we generated two chondrosarcoma cell lines, migration-prone JJ012 and Dox-resistant SW1353, to analyze the relationship between AR levels and cell functions. AR was highly expressed and secreted in mobile and drug-resistant cells. Next, we used the lentivirus-mediated RNAi system to knock down AR expression and found that AR silencing was significantly attenuated in cell migration and drug resistance. In addition, we used exogenous recombinant AR (r-AR) to confirm cell function and we introduced antibody array analysis to investigate pathways of AR activation. The results showed that AR can promote migratory activity and Dox resistance through activation of the MAPK pathway. Whereas the inhibition of the MAPK pathway has the potential to inhibit chondrosarcoma cell migration, p38 inhibition, and ERK activation may render cells more sensitive to Dox. These findings suggest that combining AR with MAPK blockade may effectively treat chondrosarcoma.

Epigallocatechin gallate inhibits hepatitis B virus infection in human liver chimeric mice.

BACKGROUND: Persistent hepatitis B virus (HBV) infection causes liver cirrhosis and hepatocellular carcinoma and constitutes a major worldwide health problem. Currently, anti-HBV drugs are limited to peginterferon and nucleos(t)ide analogs, which are costly and have considerable side effects; the development of novel, effective anti-HBV agents is crucial. METHODS: Catechins are a major group of compounds found in green tea extract and epigallocatechin gallate (EGCG) has been shown to have antiviral properties, including inhibition of cellular entry by HBV. FRG (Fah-/-/ Rag2-/-/ IL-2Rγ/-) mice were used in this study to generate chimeras carrying human primary hepatocytes, to facilitate investigation of the inhibitory effect of EGCG on HBV infection. RESULTS: Here, we show the inhibitory effect of EGCG on HBV infection and replication in HuS-E/2 cells. The inhibitory effect of EGCG on HBV infection in vivo was confirmed by monitoring HBV DNA and HBsAg in serum and immunostaining the liver tissues of the human liver chimeric mice. CONCLUSIONS: The effects of EGCG suggest a robust strategy for the treatment of HBV infection and EGCG may have therapeutic potential for the treatment of HBV-associated liver diseases.

Leptin increases VEGF expression and enhances angiogenesis in human chondrosarcoma cells.

BACKGROUND: Leptin, 16kDa product of obese gene, is adipocytokine playing critical role in regulation of body weight. In recent years, leptin is also defined as potent angiogenic factor involving in tumorigenesis, angiogenesis, and metastasis. However, it is unknown whether leptin regulates VEGF production in human chondrosarcoma and contributing the tumor-associated angiogenesis. METHODS: We analyzed protein level of leptin and VEGF in human chondrosarcoma tissues. Effects of leptin on chondrosarcoma cells were examined by in vitro and in vivo assays. In addition, intracellular signal pathways were investigated by pharmacological and genetic approaches. RESULTS: We found that both leptin and VEGF are highly expressed in human chondrosarcoma tissues, and positively correlated with tumor stage. Leptin increases VEGF production by activating OBRl receptor and MAPKs (p38, ERK, and JNK), which in turn enhances binding of AP-1 transcription factor to VEGF promoter, resulting in the transactivation of VEGF expression and subsequently promoting migration and tube formation in endothelial progenitor cells (EPCs). In vivo, knockdown leptin significantly reduces angiogenesis and tumor growth. CONCLUSION: Leptin may be a therapeutic target of angiogenesis and metastasis in chondrosarcoma. GENERAL SIGNIFICANCE: These findings provide better understanding of pathogenesis of chondrosarcoma and can utilize this knowledge to design new therapeutic strategy.

Association between extracellular signal-regulated kinase expression and the anti-allodynic effect in rats with spared nerve injury by applying immediate pulsed radiofrequency.

BACKGROUND: The application of pulsed radiofrequency (PRF) close to the dorsal root ganglia, or peripheral nerves, has been demonstrated to be effective for the treatment of chronic neuropathic pain conditions. The goal of this study was to investigate the analgesic effect of immediate PRF treatment after nerve injury and its possible cellular alterations in the dorsal horn of the spinal cord in rats with spared nerve injury (SNI). METHODS: Neuropathic pain was achieved in a SNI neuropathic pain model by ligating and cutting the common peroneal and tibial branches of the left sciatic nerve, leaving the sural nerve intact. Wistar rats were divided into four groups that received different treatments, i.e., SNI and PRF for 6 min at 45 V (SNI + PRF-45 V), at 60 V (SNI + PRF-60 V), SNI alone, and sham groups. After the SNI surgery, each rat was immediately given the PRF treatment (500 kHz, rate of 2 Hz, 20 ms duration, temperature below 42 °C) on the left sciatic nerve 0.3-0.4 cm proximal to the injured site. The behavioral measurements included mechanical allodynia and cold allodynia of the ipsilateral hind paw and were performed during the 28 days that followed the SNI surgery and PRF treatment. Total extracellular signal-regulated kinase 1 and 2 (ERK1/2) and phospho-ERK1/2 were measured using Western blot in the ipsilateral spinal cord from animals in the different groups. RESULTS: The three groups of rats with nerve injuries manifested a lower paw withdrawal threshold (PWT) in the behavioral measurement of mechanical allodynia and a shorter painful-behavior duration in the cold allodynia test over 28 days. Mechanical allodynia measurement showed that both the PRF-45 V and PRF-60 V treatment groups exhibited a more prominent antiallodynic effect than did the SNI group from days 1 to 28 after surgery. Similarly, in comparison with the SNI group, both the SNI + PRF-45 V and SNI + PRF-60 V groups had significant inhibition on the cold allodynia measurement from days 1 to 28 after surgery. Furthermore, the activation of the extracellular signal-regulated kinase 1 and 2 (ERK1/2) in the ipsilateral spinal dorsal horn of SNI rats was effectively inhibited in the SNI + PRF-45 V and SNI + PRF-60 V groups for 28 days after surgery. CONCLUSIONS: Immediate PRF application on the proximal nerve injury site provided a significant inhibition of neuropathic pain formation, accompanied by the inhibition of ERK activation.

Suppression of Dicer increases sensitivity to gefitinib in human lung cancer cells.

BACKGROUND: Accumulating evidence is revealing an important role of microRNA (miRNA) in tumor progression and chemotherapeutic resistance. Dicer is a cytoplasmic endoribonuclease type III crucial for production of mature miRNAs. The aberrant expression of Dicer has also been reportedly associated with clinical aggressiveness, prognosis, and patient survival in various cancer types. However, the molecular mechanisms of Dicer in acquired gefitinib resistance are still not clear. METHODS: In this study, we analyzed the protein level of Dicer between gefitinib-sensitive (PC9) and gefitinib-resistant (PC9/GR) non-small-cell lung cancer (NSCLC) cell lines by Western blot analysis. Silence and overexpression of the Dicer were performed to investigate the effects on gefitinib sensitivity, as assessed by (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay and sub-G1 assay of flow cytometry. To further explore the mechanism of chemoresistance, we examined whether Dicer knockdown led to modulating specific miRNAs and its miRNA target genes. RESULTS: Dicer expression was significantly increased in PC9/GR compared with PC9 cells. Knockdown of Dicer restores gefitinib sensitivity in resistant cells, and overexpression of Dicer enhances resistance to gefitinib in sensitive cells. Silencing of Dicer induces sensitivity to gefitinib in NSCLC cells through the downregulation of miR-30b/c and miR-221/222 to increase the protein level of caspase-3, resulting in an increase in gefitinib-induced apoptosis. CONCLUSIONS: Dicer contributes to the resistance to gefitinib in lung cancer. These results indicate that Dicer may be a target for diagnosis and therapy of patients with resistance to gefitinib.

Lidocaine attenuates TMZ resistance and inhibits cell migration by modulating the MET pathway in glioblastoma cells.

Glioblastoma multiforme (GBM) is the most aggressive type of malignant brain tumor. Currently, the predominant clinical treatment is the combination of surgical resection with concurrent radiotherapy and chemotherapy, using temozolomide (TMZ) as the primary chemotherapy drug. Lidocaine, a widely used amide­based local anesthetic, has been found to have a significant anticancer effect. It has been reported that aberrant hepatocyte growth factor (HGF)/mesenchymal­epithelial transition factor (MET) signaling plays a role in the progression of brain tumors. However, it remains unclear whether lidocaine can regulate the MET pathway in GBM. In the present study, the clinical importance of the HGF/MET pathway was analyzed using bioinformatics. By establishing TMZ­resistant cell lines, the impact of combined treatment with lidocaine and TMZ was investigated. Additionally, the effects of lidocaine on cellular function were also examined and confirmed using knockdown techniques. The current findings revealed that the HGF/MET pathway played a key role in brain cancer, and its activation in GBM was associated with increased malignancy and poorer patient outcomes. Elevated HGF levels and activation of its receptor were found to be associated with TMZ resistance in GBM cells. Lidocaine effectively suppressed the HGF/MET pathway, thereby restoring TMZ sensitivity in TMZ­resistant cells. Furthermore, lidocaine also inhibited cell migration. Overall, these results indicated that inhibiting the HGF/MET pathway using lidocaine can enhance the sensitivity of GBM cells to TMZ and reduce cell migration, providing a potential basis for developing novel therapeutic strategies for GBM.

Modulation of secretory factors by lipofundin contributes to its anti­neuroinflammatory effects.

As the global population ages, the prevalence of neuroinflammatory diseases such as Alzheimer's disease, Parkinson's disease and stroke continues to increase. Therefore, it is necessary to develop preventive and therapeutic methods against neuroinflammatory diseases. Lipofundin is a lipid emulsion commonly used in clinical anesthetic solvents and nutritional supplements. Lipid emulsions have been shown to possess anti-inflammatory properties. However, the potential beneficial effect of lipofundin against neuroinflammation requires elucidation. In the present study, two cell models were used to investigate the efficacy of lipofundin against neuroinflammation. In the first model, BV2 mouse microglial cells were treated with lipopolysaccharide (LPS) to induce nitric oxide (NO) production as a model of neuroinflammation. In the second model, HMC3 human microglial were activated by LPS, and changes in the secretion of factors associated with inflammation were analyzed using Luminex xMAP® technology. Griess assay results revealed that lipofundin significantly prevented and treated LPS-induced NO production. An anti-neuroinflammatory effect was also observed in HMC3 cells, where lipofundin exhibited excellent preventive and therapeutic properties by reducing the LPS-induced expression and secretion of interleukin-1ß. Notably, lipofundin also promoted the secretion of certain growth factors, suggesting a potential neuroprotective effect. These results demonstrate that, in addition to its role as a solvent for drugs and nutritional support, lipofundin may also have beneficial effects in alleviating the progression of neuroinflammation. These findings may serve as an important reference for future translational medicine applications.

Ergosterol peroxide blocks HDV infection as a novel entry inhibitor by targeting human NTCP receptor.

Hepatitis D virus (HDV), which co-infects or superinfects patients with hepatitis B virus, is estimated to affect 74 million people worldwide. Chronic hepatitis D is the most severe form of viral hepatitis and can result in liver cirrhosis, liver failure, and hepatocellular carcinoma (HCC). Currently, there are no efficient HDV-specific drugs. Therefore, there is an urgent need for novel HDV therapies that can achieve a functional cure or even eliminate the viral infection. In the HDV life cycle, agents targeting the entry step of HDV infection preemptively reduce the intrahepatic viral RNA. Human sodium taurocholate co-transporting polypeptide (hNTCP), a transporter of bile acids on the plasma membrane of hepatocytes, is an essential entry receptor of HDV and is a promising molecular target against HDV infection. Here, we investigated the effect of ergosterol peroxide (EP) on HDV infection in vitro and in vivo. EP inhibited HDV infection of hNTCP-expressing dHuS-E/2 hepatocytes by interrupting the early fusion/endocytosis step of HDV entry. Furthermore, molecular modeling suggested that EP hinders LHBsAg binding to hNTCP by blocking access to S267 and V263. In addition, we generated hNTCP-expressing transgenic (Tg) C57BL/6 mice using the Cre/loxP system for in vivo study. EP reduced the liver HDV RNA level of HDV-challenged hNTCP-Cre Tg mice. Intriguingly, EP downregulated the mRNA level of liver IFN-γ. We demonstrate that EP is a bona fide HDV entry inhibitor that acts on hNTCP and has the potential for use in HDV therapies.

α-Viniferin-Induced Apoptosis through Downregulation of SIRT1 in Non-Small Cell Lung Cancer Cells.

α-Viniferin, a natural stilbene compound found in plants and a polymer of resveratrol, had demonstrated potential anti-cancer and anti-inflammatory effects. However, the specific mechanisms underlying its anti-cancer activity were not yet fully understood and required further investigation. This study evaluated the effectiveness of α-viniferin and ε-viniferin using MTT assay. Results showed that α-viniferin was more effective than ε-viniferin in reducing the viability of NCI-H460 cells, a type of non-small cell lung cancer. Annexin V/7AAD assay results provided further evidence that the decrease in cell viability observed in response to α-viniferin treatment was due to the induction of apoptosis in NCI-H460 cells. The present findings indicated that treatment with α-viniferin could stimulate apoptosis in cells by cleaving caspase 3 and PARP. Moreover, the treatment reduced the expression of SIRT1, vimentin, and phosphorylated AKT, and also induced AIF nuclear translocation. Furthermore, this research provided additional evidence for the effectiveness of α-viniferin as an anti-tumor agent in nude mice with NCI-H460 cell xenografts. As demonstrated by the TUNEL assay results, α-viniferin promoted apoptosis in NCI-H460 cells in nude mice.

The protease allergen Pen c 13 induces allergic airway inflammation and changes in epithelial barrier integrity and function in a murine model.

Fungal allergens are associated with the development of asthma, and some have been characterized as proteases. Here, we established an animal model of allergic airway inflammation in response to continuous exposure to proteolytically active Pen c 13, a major allergen secreted by Penicillium citrinum. In functional analyses, Pen c 13 exposure led to increased airway hyperresponsiveness, significant inflammatory cell infiltration, mucus overproduction, and collagen deposition in the lung, dramatically elevated serum levels of total IgE and Pen c 13-specific IgE and IgG1, and increased production of the Th2 cytokines IL-4, IL-5, and IL-13 by splenocytes stimulated in vitro with Pen c 13. To examine the mechanisms involved in the regulation of allergenicity by Pen c 13, we performed two-dimensional fluorescence difference gel electrophoresis analysis combined with nano-LC-MS/MS, followed by bioinformatics analysis to identify potential targets that associated with allergic inflammation, which suggested that galectin-3 and laminin might be involved in novel pathogenic mechanisms. Finally, we focused on junctional proteins between cells, because, in addition to opening of the epithelial barrier by environmental proteases possibly being the initial step in the development of asthma, these proteins are also associated with actin rearrangement. Taken together, our findings indicate that Pen c 13 exposure causes junctional structure alterations and actin cytoskeletal rearrangements, resulting in increased permeability and airway structural changes. These effects probably change the lung microenvironment and foster the development of allergic sensitization.

The role of the VEGF-C/VEGFRs axis in tumor progression and therapy.

Vascular endothelial growth factor C (VEGF-C) has been identified as a multifaceted factor participating in the regulation of tumor angiogenesis and lymphangiogenesis. VEGF-C is not only expressed in endothelial cells, but also in tumor cells. VEGF-C signaling is important for progression of various cancer types through both VEGF receptor-2 (VEGFR-2) and VEGF receptor-3 (VEGFR-3). Likewise, both receptors are expressed mainly on endothelial cells, but also expressed in tumor cells. The dimeric VEGF-C undergoes a series of proteolytic cleavage steps that increase the protein binding affinity to VEGFR-3; however, only complete processing, removing both the N- and C-terminal propeptides, yields mature VEGF-C that can bind to VEGFR-2. The processed VEGF-C can bind and activate VEGFR-3 homodimers and VEGFR-2/VEGFR-3 heterodimers to elicit biological responses. High levels of VEGF-C expression and VEGF-C/VEGFRs signaling correlate significantly with poorer prognosis in a variety of malignancies. Therefore, the development of new drugs that selectively target the VEGF-C/VEGFRs axis seems to be an effective means to potentiate anti-tumor therapies in the future.

Propofol induces apoptosis and ameliorates 5­fluorouracil resistance in OSCC cells by reducing the expression and secretion of amphiregulin.

Among the different types of oral cancer, >90% of cases are oral squamous cell carcinoma (OSCC). 5­fluorouracil (5­FU) is a commonly used treatment for OSCC, but cells typically display resistance to the drug. Propofol, an intravenous anesthetic agent, exhibits certain anticancer effects, including the inhibition of cancer cell proliferation, migration and invasion. Secreted proteins, such as growth factors and cytokines are involved in cancer development and progression, but the effect of propofol on secreted proteins in OSCC is not completely understood. An MTT assay, flow cytometry and western blotting were performed to determine the anticancer effects of propofol. The secretion profile of OSCC was determined using an antibody array, and clinical importance was assessed using the Gene Expression Profiling Interactive Analysis database. The results were verified by performing reverse transcription­quantitative PCR (RT­qPCR) and western blotting. 5­FU­resistant cells were established to determine the role of the gene of interest in drug resistance. The results demonstrated that propofol decreased cell viability and promoted cell apoptosis. The antibody array results showed that propofol attenuated the secretion of multiple growth factors. The bioinformatics results indicated that amphiregulin (AREG) was expressed at significantly higher levels in cancer tissues, which was also related to poor prognosis. The results of RT­qPCR and western blotting revealed that propofol decreased AREG expression. Pretreatment with exogenous recombinant AREG increased EGFR activation and conferred propofol resistance. Moreover, the results indicated that the expression and activation of AREG was also related to 5­FU resistance, but propofol ameliorated 5­FU drug resistance. Therefore, the present study suggested that propofol combination therapy may serve as an effective treatment strategy for OSCC.

α-Viniferin and ε-Viniferin Inhibited TGF-ß1-Induced Epithelial-Mesenchymal Transition, Migration and Invasion in Lung Cancer Cells through Downregulation of Vimentin Expression.

Resveratrol has well-known anticancer properties; however, its oligomers, including α-viniferin, ε-viniferin, and kobophenol A, have not yet been well investigated. This is the first study examining the anti-epithelial-mesenchymal transition (EMT) effects of α-viniferin and ε-viniferin on A549, NCI-H460, NCI-H520, MCF-7, HOS, and U2OS cells. The results showed that α-viniferin and ε-viniferin significantly inhibited EMT, invasion and migration in TGF-ß1- or IL-1ß-induced non-small cell lung cancer. α-Viniferin and ε-viniferin also reversed TGF-ß1-induced reactive oxygen species (ROS), MMP2, vimentin, Zeb1, Snail, p-SMAD2, p-SMAD3, and ABCG2 expression in A549 cells. Furthermore, ε-viniferin was found to significantly inhibit lung metastasis in A549 cell xenograft metastatic mouse models. In view of these findings, α-viniferin and ε-viniferin may play an important role in the prevention of EMT and cancer metastasis in lung cancer.