Functional roles of female sex hormones and their nuclear receptors in cervical cancer.

There has been little progress for several decades in modalities to treat cervical cancer. While the cervix is a hormone-sensitive tissue, physiologic roles of estrogen receptor α (ERα), progesterone receptor (PR), and their ligands in this tissue are poorly understood. It has hampered critical assessments of data in early epidemiologic and clinical studies for cervical cancer. Experimental evidence obtained from studies using mouse models has provided new insights into the molecular mechanism of ERα and PR in cervical cancer. In a mouse model expressing human papillomavirus (HPV) oncogenes, exogenous estrogen promotes cervical cancer through stromal ERα. In the same mouse model, genetic ablation of PR promotes cervical carcinogenesis without exogenous estrogen. Medroxyprogesterone acetate, a PR-activating drug, regresses cervical cancer in the mouse model. These results support that ERα and PR play opposite roles in cervical cancer. They further support that ERα inhibition and PR activation may be translated into valuable treatment for a subset of cervical cancers.

Non-Metabolic Functions of PKM2 Contribute to Cervical Cancer Cell Proliferation Induced by the HPV16 E7 Oncoprotein.

Pyruvate kinase M2 (PKM2) mainly catalyzes glycolysis, but it also exerts non-glycolytic functions in several cancers. While it has been shown to interact with the human papillomavirus 16 (HPV16) E7 oncoprotein, the functional significance of PKM2 in HPV-associated cervical cancer has been elusive. Here, we show that HPV16 E7 increased the expression of PKM2 in cervical cancer cells. TCGA data analyses revealed a higher level of PKM2 in HPV+ than HPV- cervical cancers and a worse prognosis for patients with high PKM2 expression. Functionally, we demonstrate that shRNA-mediated PKM2 knockdown decreased the proliferation of HPV+ SiHa cervical cancer cells. PKM2 knockdown also inhibited the E7-induced proliferation of cervical cancer cells. ML265 activating the pyruvate kinase function of PKM2 inhibited cell cycle progression and colony formation. ML265 treatments decreased phosphorylation of PKM2 at the Y105 position that has been associated with non-glycolytic functions. On the contrary, HPV16 E7 increased the PKM2 phosphorylation. Our results indicate that E7 increases PKM2 expression and activates a non-glycolytic function of PKM2 to promote cervical cancer cell proliferation.

A Telomerase-Derived Peptide Exerts an Anti-Hepatitis B Virus Effect via Mitochondrial DNA Stress-Dependent Type I Interferon Production.

Previously, a telomerase-derived 16-mer peptide, GV1001, developed as an anticancer vaccine, was reported to exert antiviral effects on human immunodeficiency virus or hepatitis C virus in a heat shock protein-dependent manner. Here we investigated whether GV1001 exerts antiviral effects on hepatitis B virus (HBV) and elucidated its underlying mechanisms. GV1001 inhibited HBV replication and hepatitis B surface antigen (HBsAg) secretion in a dose-dependent manner, showing synergistic antiviral effects with nucleos(t)ide analogs (NAs) including entecavir and lamivudine. This peptide also inhibited viral cccDNA and pgRNA. The intravenous GV1001 treatment of transgenic mice had anti-HBV effects. Our mechanistic studies revealed that GV1001 suppresses HBV replication by inhibiting capsid formation via type I interferon-mediated induction of heme oxygenase-1 (HO-1). GV1001 promoted the mitochondrial DNA stress-mediated release of oxidized DNA into the cytosol, resulting in IFN-I-dependent anti-HBV effects via the STING-IRF3 axis. We found that the anti-HBV effect of GV1001 was due to its ability to penetrate into the cytosol via extracellular heat shock protein, leading to phagosomal escape-mediated mtDNA stress. We demonstrated that the cell-penetrating and cytosolic localization capacity of GV1001 results in antiviral effects on HBV infections via mtDNA stress-mediated IFN-I production. Thus, GV1001, a peptide proven to be safe for human use, may be an anti-HBV drug that can be synergistically used with nucleot(s)ide analog.

All-trans retinoic acid regulates TGF-ß1-induced extracellular matrix production via p38, JNK, and NF-κB-signaling pathways in nasal polyp-derived fibroblasts.

BACKGROUND: All-trans retinoic acid (ATRA), a derivative of vitamin A, is known to have anti-fibrogenic effects and regulates cell proliferation and differentiation. Therefore, these abilities of ATRA may influence tissue remodeling in the upper airway. The aims of the present study were to investigate the effects of ATRA on the myofibroblast differentiation, extracellular matrix (ECM) production, cell migration, and collagen gel contraction and to determine the molecular mechanisms of ATRA in TGF-ß1-induced nasal polyp-derived fibroblasts (NPDFs). METHODS: NPDFs were isolated from nasal polyp. Cytotoxicity was evaluated by 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl-tetrazolium bromide assay. TGF-ß1-induced fibroblasts were pretreated with ATRA. The expression levels of alpha-smooth muscle actin (α-SMA), collagen type 1, fibronectin, phospho-mitogen-activated protein kinase, and p-p50 (nuclear factor-kappaB [NF-κB]) were measured by Western blot analysis, real-time polymerase chain reaction, and/or immunofluorescence staining. Cell migration was analyzed with cell migration scratch assay and Transwell migration assay. Collagen contractile activity was measured using a collagen gel contraction assay. RESULTS: ATRA had no significant cytotoxic effect in NPDFs. Expression levels of α-SMA, collagen type 1, and fibronectin stimulated by TGF-ß1 were significantly downregulated in the ATRA-pretreated fibroblasts. TGF-ß1-induced cell migration and collagen gel contraction were significantly inhibited by ATRA pretreatment. ATRA also significantly inhibited phosphorylation of c-Jun N-terminal kinase (JNK), p38, and p50 in TGF-ß1-induced NPDFs, but did not inhibit phosphorylation of extracellular signal-related kinase (ERK). CONCLUSION: ATRA downregulated myofibroblast differentiation, ECM production, cell migration, and collagen gel contraction via p38, JNK-dependent NF-κB-signaling pathways in TGF-ß1-induced NPDFs. The findings suggest that ATRA could serve as a novel therapeutic agent to ameliorate nasal polyp development.

Effect of MeCP2 on TGF- ß1-induced Extracellular Matrix Production in Nasal Polyp-derived Fibroblasts.

Purpose Methyl-CpG-binding protein 2 (MeCP2), known as a transcriptional regulator, has been suggested to play an important role in myofibroblast differentiation in the lung. The purpose of this study was to investigate the role of MeCP2 in transforming growth factor (TGF)- ß1-induced myofibroblast differentiation and extracellular matrix (ECM) production in nasal polyp-derived fibroblasts (NPDFs). Methods To identify the expression of MeCP2 in nasal polyp tissues, immunohistochemistry staining and Western blot were performed. TGF- ß1-induced NPDFs were treated with 5-azacytidine, a DNA methylation inhibitor, and the expression levels of α-SMA and fibronectin were determined by semiquantitative reverse transcription polymerase chain reaction, immunofluorescent staining, and Western blotting. The total soluble collagen was analyzed by the Sircol collagen assay. MeCP2 silenced by MeCP2-specific small interference ( si) RNA was verified by Western blot. Results The expression levels of MeCP2 increased in nasal polyp tissues compared to normal inferior turbinate tissues. 5-Azacytidine significantly inhibited the expression of α-SMA and fibronectin mRNA in a dose-dependent manner. In addition, 5-azacytidine suppressed collagen production and the expression of MeCP2 in the same manner. The expression levels of a-SMA and collagen production were significantly blocked by MeCP2 silencing in TGF- ß1-induced NPDFs. Conclusions Our data suggest that MeCP2 plays an essential role in TGF- ß1-induced myofibroblast differentiation and ECM production in NPDFs.

Sex disparity in viral load, inflammation and liver damage in transgenic mice carrying full hepatitis B virus genome with the W4P mutation in the preS1 region.

AIM: To study sex disparity in susceptibility to hepatocellular carcinoma (HCC), we created a transgenic mouse model that expressed the full hepatitis B virus (HBV) genome with the W4P mutation. METHODS: Transgenic mice were generated by transferring the pHY92-1.1x-HBV-full genome plasmid (genotype A2) into C57Bl/6N mice. We compared serum levels of hepatitis B surface antigen (HBsAg), interleukin (IL)-6, and the liver enzymes alanine aminotransferase (ALT) and aspartate transaminase (AST), as well as liver histopathological features in male and female transgenic (W4P TG) mice and in nontransgenic littermates of 10 mo of age. RESULTS: W4P TG males exhibited more pronounced hepatomegaly, significantly increased granule generation in liver tissue, elevated HBsAg expression in the liver and serum, and higher serum ALT and IL-6 levels compared to W4P TG females or littermate control groups. CONCLUSION: Together, our data indicate that the W4P mutation in preS1 may contribute to sex disparity in susceptibility to HCC by causing increased HBV virion replication and enhanced IL-6-mediated inflammation in male individuals. Additionally, our transgenic mouse model that expresses full HBV genome with the W4P mutation in preS1 could be effectively used for the studies of the progression of liver diseases, including HCC.

Role of adenosine monophosphate-activated protein kinase on cell migration, matrix contraction, and matrix metalloproteinase-1 and matrix metalloproteinase-2 production in nasal polyp-derived fibroblasts.

PURPOSE: Activation of adenosine monophosphate-activated protein kinase (AMPK) by metformin, as a master regulator of metabolism, is involved in airway tissue remodeling. Here, we investigated the physical role of AMPK on cell migration, matrix contraction, and the production of matrix metalloproteinases (MMP) in nasal polyp-derived fibroblasts (NPDF). METHODS: Primary NPDFs from six patients with chronic rhinosinusitis and nasal polyps were isolated and cultured. To assess the effect of AMPK on fibroblast migration, we conducted scratch and migration assays in NPDF treated with metformin and/or compound C. A collagen gel contraction assay measured activity of contractile. MMP expression was measured with reverse transcription-polymerase chain reaction, Western blot, and zymography. To evaluate for specific AMPK action, we examined by AMPK small interfering RNA. RESULTS: Metformin, an activator of AMPK, significantly inhibited cell migration in NPDFs in a dose-dependent manner. Compound C, an inhibitor of AMPK, partially reversed the inhibitory effect of metformin. Metformin also significantly decreased contractile activity, with a concomitant reduction in the production of MMP-1 and MMP-2 but not of MMP-9. Specific silencing that targeted AMPK resulted in the enhancement of mobility and contractility and in the production of MMP-1 and MMP-2. CONCLUSION: AMPK played an important role in regulating cell migration, matrix contraction, and MMP production in NPDFs, which provided data that AMPK activator might be a therapeutic target for the prevention of tissue remodeling in nasal polyps.

Vitamin D attenuates myofibroblast differentiation and extracellular matrix accumulation in nasal polyp-derived fibroblasts through smad2/3 signaling pathway.

To investigate the potential role of vitamin D (1,25(OH)2D3) in preventing the development of nasal polyps, we examined the effect of vitamin D on myofibroblast differentiation and extracellular matrix (ECM) production in TGF-ß1-induced nasal polyp-derived fibroblasts (NPDFs) and elucidated the mechanisms underlying its inhibitory effect. 1,25(OH)2D3 significantly reduced expression levels of α-SMA, a myofibroblast marker, and fibronectin, a representative ECM component, in a dose-dependent manner in TGF-ß1-induced NPDFs. 1,25(OH)2D3 suppressed activated Smad2/3 in time-course. Up-regulation of α-SMA, fibronectin and phosphorylation of Smad2/3 by TGF-ß1 was unaffected by 1,25(OH)2D3 in NPDFs after vitamin D receptor-specific siRNA transfection. We confirmed that the Smad2/3-specific inhibitor SIS3 inactivated Smad2/3 and reduced α-SMA and fibronectin expression. Furthermore, acetylation of histone H3 was compromised by 1,25(OH)2D3, leading to inhibition of collagen 1A1, collagen 1A2 and α-SMA gene expression. Treatment with 1,25(OH)2D3 also significantly suppressed TGF-ß1-enhanced contractility and motility in a contraction assay and Transwell migration assay. Finally, 1,25(OH)2D3 had a similar effect in ex vivo organ cultures of nasal polyps. Taken together, our results suggest that 1,25(OH)2D3 might be an effective therapy for nasal polyps by reducing myofibroblast differentiation and ECM production mediated by Smad2/3-dependent TGF-ß1 signaling pathways in NPDFs.

Chemical Chaperone of Endoplasmic Reticulum Stress Inhibits Epithelial-Mesenchymal Transition Induced by TGF-ß1 in Airway Epithelium via the c-Src Pathway.

Epithelial-mesenchymal transition (EMT) is a biological process that allows epithelial cells to assume a mesenchymal cell phenotype. EMT is considered as a therapeutic target for several persistent inflammatory airway diseases related to tissue remodeling. Herein, we investigated the role of endoplasmic reticulum (ER) stress and c-Src in TGF-ß1-induced EMT. A549 cells, primary nasal epithelial cells (PNECs), and inferior nasal turbinate organ cultures were exposed to 4-phenylbutylic acid (4PBA) or PP2 and then stimulated with TGF-ß1. We found that E-cadherin, vimentin, fibronectin, and α-SMA expression was increased in nasal polyps compared to inferior turbinates. TGF-ß1 increased the expression of EMT markers such as E-cadherin, fibronectin, vimentin, and α-SMA and ER stress markers (XBP-1s and GRP78), an effect that was blocked by PBA or PP2 treatment. 4-PBA and PP2 also blocked the effect of TGF-ß1 on migration of A549 cells and suppressed TGF-ß1-induced expression of EMT markers in PNECs and organ cultures of inferior turbinate. In conclusion, we demonstrated that 4PBA inhibits TGF-ß1-induced EMT via the c-Src pathway in A549 cells, PNECs, and inferior turbinate organ cultures. These results suggest an important role for ER stress and a diverse role for TGF-ß1 in upper airway chronic inflammatory disease such as CRS.

A novel hepatitis B virus-derived cis-acting sequence that enhances expression of transgenes delivered by plasmid vectors in eukaryote cell culture systems.

We tested the effectiveness of a novel 13-bp hepatitis B virus (HBV)-derived cis-acting element (CAE) (ACCTCGACAAGGC), called the DT2 CAE, in augmenting transgene expression delivered by plasmid vectors in eukaryotic cells. The addition of the DT2 CAE just upstream of the start codon of several different target proteins (luciferase, EGFP, LHB, HBsAg, and MIF) in DNA plasmid constructs enhanced their translation in a posttranscriptional manner, irrespective of cell type (cell lines or primary cells) or promoter (CMV or HBV preS1 promoters), suggesting its feasibility for enhanced protein production in eukaryotic cell systems. In conclusion, a novel HBV-derived DT2 CAE could be used effectively for enhanced protein production in eukaryotic cell culture systems.

Glucocorticoids ameliorate TGF-ß1-mediated epithelial-to-mesenchymal transition of airway epithelium through MAPK and Snail/Slug signaling pathways.

Chronic rhinosinusitis with nasal polyps (CRSwNP) is closely associated with tissue remodeling. Epithelial-to-mesenchymal transition (EMT), a process of tissue remodeling, can be a therapeutic target of CRSwNP. Glucocorticoids are a type of steroid hormone that is used primarily in medical therapy for patients with CRSwNP; however, their effects on EMT in the airway epithelium remain unknown. To investigate the effects of dexamethasone and fluticasone propionate, a class of glucocorticoids, on transforming growth factor-ß1 (TGF-ß1) -induced EMT, we used A549 cells, human primary nasal epithelial cells (hPNECs) and ex vivo organ culture of the inferior turbinate. TGF-ß1 induced changes in cell morphology, suppressed the expression of E-cadherin and enhanced the expression of a-smooth muscle actin, vimentin and fibronectin in A549 cells. However, glucocorticoids inhibited EMT, migration and invasion enhancement by TGF-ß1. We found that the induction of phosphorylated ERK, p38 and the activity of Snail and Slug transcription factors by TGF-ß1 were suppressed by glucocorticoids. Glucocorticoids also had a similar effect in hPNECs and ex vivo organ cultures of the inferior turbinate. These findings suggest that glucocorticoids might be a useful therapy for preventing tissue remodeling by blocking the EMT initiated by TGF-ß1-induced MAPK and Snail/Slug signaling pathways in CRSwNP.

Effect of doxycycline on epithelial-mesenchymal transition via the p38/Smad pathway in respiratory epithelial cells.

PURPOSE: Doxycycline has antibacterial and anti-inflammatory effects, and it also suppresses collagen biosynthesis. This study aimed to confirm the effects and mechanism of doxycycline on transforming growth factor (TGF) beta 1 induced epithelial-mesenchymal transition and cell migration in A549 and primary nasal epithelial cells. METHODS: A 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl-tetrazolium bromide assay and phalloidin-fluorescein isothiocyanate staining were used to evaluate cytotoxicity and cellular morphologic changes. Western blot and immunofluorescence staining were used to determine the expression levels of E-cadherin, vimentin, alpha-smooth muscle actin, fibronectin, phosphorylated Smad2/3, and mitogen-activated protein kinases. Scratch and transwell migration assays were used to assess cellular migration ability. RESULTS: Doxycycline (0-10 µg/mL) had no significant cytotoxic effects in A549 and primary nasal epithelial cells. Increased expression of mesenchymal markers, including vimentin, alpha-smooth muscle actin, and fibronectin in TGF beta 1 induced A549 cells were downregulated by doxycycline treatment. In contrast, E-cadherin expression was upregulated in TGF beta 1 induced A549 cells. An in vitro cell migration assay showed that doxycycline also inhibited the ability of TGF beta 1 induced migration. Doxycycline treatment suppressed the activation of Smad2/3 and p38, whereas its inhibitory effects were similar to each element-specific inhibitor in A549 and primary nasal epithelial cells. CONCLUSION: Doxycycline inhibited TGF beta 1 induced epithelial-to-mesenchymal transition and migration by targeting Smad2/3 and p38 signal pathways in respiratory epithelial cells.

Baicalin Down-Regulates IL-1ß-Stimulated Extracellular Matrix Production in Nasal Fibroblasts.

PURPOSE: Baicalin, a Chinese herbal medicine, has anti-fibrotic and anti-inflammatory effects. The aims of present study were to investigate the effects of baicalin on the myofibroblast differentiation, extracellular matrix production, migration, and collagen contraction of interleukin (IL)-1ß-stimulated nasal fibroblasts and to determine the molecular mechanism of baicalin in nasal fibroblasts. METHODS: Nasal fibroblasts were isolated from the inferior turbinate of patients. Baicalin was used to treat IL-1ß-stimulated nasal fibroblasts. To evaluate cytotoxicity, a 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl-tetrazolium bromide assay was used. The expression levels of α-smooth muscle actin (SMA), fibronectin, phospho-mitogen-activated protein kinase (p-MAPK), p-Akt, p-p50, p-p65, and p-IκBα were measured by western blotting, reverse transcription-polymerase chain reaction (RT-PCR),or immunofluorescence staining. Fibroblast migration was analyzed with scratch assays and transwell migration assays. Total collagen was evaluated with the Sircol collagen assay. Contractile activity was measured with a collagen gel contraction assay. RESULTS: Baicalin (0-50 µM) had no significant cytotoxic effects in nasal fibroblasts. The expression of α-SMA and fibronectin were significantly down-regulated in baicalin-treated nasal fibroblasts. Migration, collagen production, and contraction of IL-1ß-stimulated nasal fibroblasts were significantly inhibited by baicalin treatment. Baicalin also significantly down-regulated p-MAPK, p-Akt, p-p50, p-p65, and p-IκBα in IL-1ß-stimulated nasal fibroblasts. CONCLUSIONS: We showed that baicalin down-regulated myofibroblast differentiation, extracellular matrix production, migration, and collagen contraction via the MAPK and Akt/ NF-κB pathways in IL-1ß-stimulated nasal fibroblasts.

Diesel Exhaust Particles Upregulate Interleukins IL-6 and IL-8 in Nasal Fibroblasts.

BACKGROUND: Diesel exhaust particles (DEP) are a major source of air pollution. Nasal fibroblasts are known to produce various cytokines and chemokines. The aim of this study was to evaluate DEP-induced cytokines and chemokines in nasal fibroblasts and to identify the signaling pathway involved. METHODS: A cytokine and chemokine array performed after stimulation of nasal fibroblasts with DEP revealed that levels of IL-6 and IL-8 were increased most significantly among various cytokines and chemokines. RT-PCR and ELISA were used to determine the mRNA and protein expression levels of IL-6 and IL-8. Signaling pathways of p-38, Akt, and NF-κB were analyzed by western blotting, luciferase assay, and ELISA. Organ cultures of nasal interior turbinate were also developed to demonstrate the ex vivo effect of DEP on the expression of IL-6 and IL-8 and the associated signaling pathway. RESULTS: DEP increased the expressions of IL-6 and IL-8 in nasal fibroblasts at mRNA and protein levels. DEP induced phosphorylation of p38, Akt, and NF-κB, whereas inhibitors of p38, Akt, and NF-κB blocked these phophorylations and the expressions of IL-6 and IL-8. These findings were also observed in ex vivo organ culture of nasal inferior turbinate. CONCLUSIONS: DEP induces expression of IL-6 and IL-8 via p38, Akt, and NF-κB signaling pathways in nasal fibroblasts. This finding suggests that air pollution might induce or aggravate allergic rhinitis or chronic rhinosinusitis.

X region mutations of hepatitis B virus related to clinical severity.

Chronic hepatitis B virus (HBV) infection remains a major health problem, with more than 240 million people chronically infected worldwide and potentially 650000 deaths per year due to advanced liver diseases including liver cirrhosis and hepatocellular carcinoma (HCC). HBV-X protein (HBx) contributes to the biology and pathogenesis of HBV via stimulating virus replication or altering host gene expression related to HCC. The HBV X region contains only 465 bp encoding the 16.5 kDa HBx protein, which also contains several critical cis-elements such as enhancer II, the core promoter and the microRNA-binding region. Thus, mutations in this region may affect not only the HBx open reading frame but also the overlapped cis-elements. Recently, several types of HBx mutations significantly associated with clinical severity have been described, although the functional mechanism in most of these cases remains unsolved. This review article will mainly focus on the HBx mutations proven to be significantly related to clinical severity via epidemiological studies.

Precore/core region mutations of hepatitis B virus related to clinical severity.

Despite the availability of an effective vaccine, hepatitis B virus (HBV) infection remains a major health problem, with more than 350 million chronically infected people worldwide and over 1 million annual deaths due to cirrhosis and liver cancer. HBV mutations are primarily generated due both to a lack of proofreading capacity by HBV polymerase and to host immune pressure, which is a very important factor for predicting disease progression and therapeutic outcomes. Several types of HBV precore/core (preC/C) mutations have been described to date. The host immune response against T cells drives mutation in the preC/C region. Specifically, preC/C mutations in the MHC class II restricted region are more common than in other regions and are significantly related to hepatocellular carcinoma. Certain mutations, including preC G1896A, are also significantly related to HBeAg-negative chronic infection. This review article mainly focuses on the HBV preC/C mutations that are related to disease severity and on the HBeAg serostatus of chronically infected patients.

A telomerase-derived peptide regulates reactive oxygen species and hepatitis C virus RNA replication in HCV-infected cells via heat shock protein 90.

GV1001, a synthetic peptide derived from human telomerase, has a range of diverse biological activities, including an antioxidant function. Here, we investigated the role of GV1001 in hepatitis C virus (HCV)-infected Huh7.5 (JFH-1) cells. We showed that GV1001 inhibited the production of ROS with decreased MAP kinase signaling. Interestingly, GV1001 lost its antioxidant activity as ROS levels decreased, resulting in a reduction in extracellular heat shock protein 90 (eHSP90) as low-density lipoprotein receptor-related protein 1 (LRP1) was blocked or knocked-down. GV1001 binds to eHSP90 and is delivered into the cell by endocytosis via LRP1. Endocytosed GV1001 finally suppressed ROS generation, presumably by hindering the interaction between eHSP90 and NADPH oxidase (NOX). Importantly, GV1001 suppressed HCV RNA replication in JFH-1 cells by inhibiting the binding of HSP90 to FKBP8, a member of the FK506-binding protein family. We also found that HSP90 expression was high in HCV-infected hepatocytes. Therefore, our data suggest that GV1001 may be a good therapeutic agent by controlling HCV RNA replication, as well as by preferentially targeting cells under conditions of oxidative stress.

Effect of doxycycline on transforming growth factor-beta-1-induced matrix metalloproteinase 2 expression, migration, and collagen contraction in nasal polyp-derived fibroblasts.

PURPOSE: It is well known that doxycycline has antibacterial and anti-inflammatory effects. In this study, we aimed to investigate the effects of doxycycline on the transforming growth factor (TGF) beta 1-induced matrix metalloproteinase (MMP) 2 expression, migration, and collagen contraction, and to determine its molecular mechanism on nasal polyp-derived fibroblasts (NPDF). METHODS: NPDFs were isolated from the nasal polyps of six patients. Doxycycline was used to pretreat TGF-beta-1-induced NPDFs and ex vivo organ cultures of nasal polyps. Cytotoxicity was evaluated by using a 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl-tetrazolium bromide assay. Smad2/3 is one of the major transcription factors of TGF-beta signaling. The expression levels of MMP2 and Smad2/3 were measured by using Western blotting, reverse transcription-polymerase chain reaction, and immunofluorescence staining. The enzymic activity of MMP2 was analyzed by using gelatin zymography. Fibroblast migration was evaluated by using transwell migration assays. Contractile activity was measured by a collagen gel contraction assay. RESULTS: The expression level of MMP2 in nasal polyp tissues increased in comparison with inferior turbinate tissues. TGF-beta-1-induced NPDFs were not affected by doxycycline (0-40 µg/mL). The expression levels of MMP2 and activation of Smad2/3 in TGF-beta-1-induced NPDFs and in organ cultures of nasal polyps were significantly downregulated with doxycycline pretreatment. Doxycycline also reduced TGF-beta-1-induced fibroblast migration and collagen contraction in NPDFs. CONCLUSION: Doxycycline inhibited TGF-beta-1-induced MMP2 expression, migration, and collagen contraction via the Smad2/3 signal pathways in NPDFs.

Development of Fok-I based nested polymerase chain reaction-restriction fragment length polymorphism analysis for detection of hepatitis B virus X region V5M mutation.

AIM: To develop a Fok-I nested polymerase chain reaction (PCR)-restriction fragment length polymorphism analysis (PRA) method for the detection of hepatitis B virus X region (HBx) V5M mutation. METHODS: Nested PCR was applied into DNAs from 198 chronic patients at 2 different stages [121 patients with hepatocellular carcinoma (HCC) and 77 carrier patients]. To identify V5M mutants, digestion of nested PCR amplicons by the restriction enzyme Fok-I (GGA TGN9↓) was done. For size comparison, the enzyme-treated products were analyzed by electrophoresis on 2.5% agarose gels, stained with ethidium bromide, and visualized on a UV transilluminator. RESULTS: The assay enabled the identification of 69 patients (sensitivity of 34.8%; 46 HCC patients and 23 carrier patients). Our data also showed that V5M prevalence in HCC patients was significantly higher than in carrier patients (47.8%, 22/46 patients vs 0%, 0/23 patients, P < 0.001), suggesting that HBxAg V5M mutation may play a pivotal role in HCC generation in chronic patients with genotype C infections. CONCLUSION: The Fok-I nested PRA developed in this study is a reliable and cost-effective method to detect HBxAg V5M mutation in chronic patients with genotype C2 infection.

Discovery of a Novel Mutation (X8Del) Resulting in an 8-bp Deletion in the Hepatitis B Virus X Gene Associated with Occult Infection in Korean Vaccinated Individuals.

Universal infantile hepatitis B virus (HBV) vaccination may lead to an increase in vaccine escape variants, which may pose a threat to the long-term success of massive vaccination. To determine the prevalence of occult infections in Korean vaccinated individuals, 87 vaccinated subjects were screened for the presence of HBV DNA using both the nested PCR protocol and the VERSANT HBV DNA 3.0 assay. The mutation patterns of variants were analyzed in full-length HBV genome sequences. Their HBsAg secretion and replication capacities were investigated using both in vitro transient transfection and in vivo hydrodynamic injection. The presence of HBV DNA was confirmed in 6 subjects (6.9%). All six variants had a common mutation type (X8Del) composed of an 8-bp deletion in the C-terminal region of the HBV X gene (HBxAg). Our in vitro and in vivo analyses using the full-length HBV genome indicated that the X8Del HBxAg variant reduced the secretion of HBsAg and HBV virions compared to the wild type. In conclusion, our data suggest that a novel mutation (X8Del) may contribute to occult HBV infection in Korean vaccinated individuals via a reduced secretion of HBsAg and virions, possibly by compromising HBxAg's transacting capacity.