CAF-derived midkine promotes EMT and cisplatin resistance by upregulating lncRNA ST7-AS1 in gastric cancer.

This study aimed to investigate the role of cancer-associated fibroblast (CAF)-derived midkine (MK) in cisplatin (DDP) resistance. The primary cultures of CAFs and non-cancer fibroblasts (NFs) were isolated and purified. The DDP-resistant gastric cancer (GC) cells were cultured with CAF-conditioned medium. QRT-PCR and Elisa assays were employed to determine MK expression. The expression of ST7-AS1 was measured by qRT-PCR. The impact of CAFs, MK, and ST7-AS1 silencing on DDP resistance was determined by MTT and Annexin V/PI staining assay. Expression of EMT markers and PI3K/AKT was determined by Western blot and qRT-PCR. The role of MK in DDP resistance was confirmed in a xenograft model. Incubation with CAF-conditioned medium increased the IC50 to DDP. Also, incubation with CAF-conditioned medium increased cell viability, reduced cell apoptosis, and promoted EMT in DDP-resistant GC cells, which were all blocked with MK neutralization antibody treatment. MK increased the DDP resistance and upregulated the expression of ST7-AS1 in DDP-resistant GC cells. Additionally, ST7-AS1 knockdown increased the sensitivity to DDP by inhibiting EMT. Moreover, ST7-AS1 knockdown significantly decreased the phosphorylation of PI3K and AKT, and suppressed EMT, which were restored by MK addition. Finally, MK promoted tumor growth and DDP resistance in a mice model bearing the SGC-7901/DDP xenografts. CAF-derived MK promotes EMT-mediated DDP resistance via upregulation of ST7-AS1 and activation of PI3K/AKT pathway.

LncRNA HCG18 upregulates TRAF4/TRAF5 to facilitate proliferation, migration and EMT of epithelial ovarian cancer by targeting miR-29a/b.

BACKGROUND: Although long noncoding RNA HLA complex group 18 (lncRNA HCG18) has been suggested to regulate cell growth in several tumours, the function of HCG18 in epithelial ovarian cancer (EOC) and its mechanism are still unclear. METHODS: shRNAs were applied to reduce HCG18 and related genes. For overexpression of miRNA, a miRNA mimic was transfected into cells. Quantitative real-time PCR (qRT-PCR) was used to detect levels of HCG18, miR-29a/b, and mRNAs. MTT, colony formation, wound healing and Transwell assays were used to evaluate cell proliferation, migration and invasion, respectively. A luciferase reporter assay was utilized to evaluate NF-κB activity and the binding of miRNAs with HCG18 or TRAF4/5. BALB nude mice injected with cells stably expressing shHCG18 or shNC were used for in vivo modelling. Subcutaneous tumour growth was monitored in nude mice, and immunohistochemistry (IHC) was used to determine expression of the proliferation marker Ki67. RESULTS: Abnormal expression of HCG18 and miR-29a/b was observed in EOC tissues. Knockdown of HCG18 using shRNA inhibited proliferation, migration, EMT and the proinflammatory pathway in EOC cells. miR-29a/b mimics and TRAF4/5 knockdown exhibited effects similar to HCG18 knockdown. Further experiments suggested that HCG18 directly targets miR-29a/b and upregulates TRAF4/5 expression, which are inhibited by targeting miR-29a/b. Moreover, overexpression of TRAF4/5 antagonized the inhibitory effect of HCG18 knockdown, suggesting that they are involved in HCG18-mediated oncogenic effects. Silencing HCG18 reduced tumour size and levels of Ki67 and TRAF4/5 while increasing miR-29a/b levels in vivo. CONCLUSIONS: Taken together, our data revealed an oncogenic signalling pathway mediated by HCG18 in ovarian cell lines, which functions as a ceRNA of miR-29a/b and thus derepresses expression levels of TRAF4/5, facilitating NF-κB pathway-mediated promotion of EOC cell proliferation and migration.

Substance P prevents doxorubicin­induced cardiomyocyte injury by regulating apoptosis and autophagy: In vitro and in vivo evidence.

The function of substance P (SP) in myocardial ischemia is well understood, but its effects on congestive heart failure are unclear. The present study aimed to use in vitro and in vivo approaches to investigate the effects of SP on doxorubicin­induced cardiomyocyte injury. Pathological changes, apoptosis, cardiomyocyte ultrastructure and molecular mechanisms were evaluated in vitro and in vivo. The effects of SP on cell viability of H9c2 myocardial cells were evaluated using the Cell Counting Kit­8 and flow cytometry. B­cell lymphoma 2 (Bcl­2), Bcl­2­associated X protein (Bax), Beclin­1 and microtubule­associated protein 1A/1B­light chain 3 (LC3) were detected by western blotting. Heart failure in rats was established by intraperitoneal injection of doxorubicin. The in vitro data demonstrated that SP at concentrations of 1 µg/ml inhibited doxorubicin­induced apoptosis of H9c2 cells. Administration of doxorubicin reduced Bcl­2, Beclin­1 and LC3 expression levels in H9c2 cells, while having no effect on Bax levels. Administration of SP to these doxorubicin­treated cells did not affect Bcl­2 or Bax expression, but further reduced Beclin­1 while inhibiting the reduction in LC3 expression. In vivo, food intake was significantly increased in rats in the SP group compared with the model group. Cardiomyocytes in the heart­failure group underwent dysfunctional autophagy as ascertained by transmission electron microscopy. Compared with the heart­failure group, these pathological changes, including loss of striations and vacuolation, were inhibited by SP treatment, which promoted Bax expression, reduced Beclin­1 expression and inhibited the reduction in LC3 expression. Taken together, SP reduced cardiomyocyte apoptosis in doxorubicin­induced cardiomyocyte injury, likely by promoting autophagy, which suggested that SP is a potential therapeutic target for doxorubicin­induced heart failure.

[Effect of moxibustion combined with benazepril on expression of IL-18 and phosphorylated protein kinase B in myocardial tissue of rats with chronic heart failure].

OBJECTIVE: To observe the effect of moxibustion combined with benazepril on cardiac function and expression levels of myocardial interleukin-18(IL-18), phosphorylated protein kinase B(p-Akt) in rats with chronic heart failure (CHF), so as to explore its underlying mechanisms in improvement of CHF. METHODS: Fifty male rats were randomly divided into normal, model, moxibustion, benazepril and moxibustion+benazepril groups (n=10 rats per group). The CHF model was established by intraperitoneal injection of doxorubicin hydrochloride solution (DOX, 2.5 mg/kg) twice a week for 4 weeks. After successful modeling, the rats in the normal and model groups were fed with normal diet, and fixed on a rat plate for 20 min each time without any treatment. Mild moxibustion was applied to bilateral "Feishu" (BL13) and "Xinshu" (BL15) for 20 min each time, for 3 weeks in the moxibustion and moxibustion+benazepril groups. Rats of the benazepril and moxibustion+benazepril groups received gavage of benazepril (2 mg/kg) once daily for 3 weeks. The general behaviors of rats were observed. The ejection fraction (EF), left ventricular diameter shortening (FS), left ventricular end-diastolic diameter (LVIDd), left ventricular end-systolic diameter (LVIDs), heart rate (HR) and ventricular septal thickness (IVS) were examined by echocardiography. The content of serum N-terminal pro-brain natriuretic peptide (NT-proBNP) was detected by enzyme-linked immunosorbent assay, and expression levels of myocardial IL-18, p-Akt were detected by Western blot. RESULTS: Compared with the normal group, the EF, FS, IVS, and myocardial p-Akt expression level were significantly reduced (P<0.01), and the LVIDd, LVIDs, HR, and serum NT-proBNP content and myocardial IL-18 expression level were significantly increased in the model group (P<0.01). In comparison with the model group, the EF, FS, IVS, and myocardial p-Akt were remarkably up-regulated (P<0.05, P<0.01), and the LVIDd, LVIDs, HR, serum NT-proBNP content, and myocardial IL-18 expression level were significantly down-regulated (P<0.05, P<0.01) in the moxibustion, benazepril, and moxibustion+benazepril groups. Compared with the moxibustion+benazepr group, the levels of LVIDs, HR, serum NT-proBNP and myocardial IL-18 expression were obviously higher (P<0.05, P<0.01), while the levels of EF, FS, IVS and p-Akt were significantly lower in the moxibustion and benazepril groups (P<0.01). CONCLUSION: Moxibustion combined with benazepril improves cardiac function in CHF rats, and is superior to simple moxibustion and simple benazepril in reducing IL-18 expression and increasing p-Akt expression in myocardial tissue.

CDH11 Regulates Adhesion and Transcellular Migration of Tongue Squamous Cell Carcinoma.

PURPOSE: CDH11, as a member of cadherins, mediates homotypic cell adhesion. Some studies have shown that CDH11 plays an important role in the development of tumors, especially in the processes of tumor invasion and metastasis. While features of CDH11 in tongue squamous cell carcinoma (TSCC) are still indeterminate, the purpose of the present study is to explore the role of CDH11 in TSCC. METHODS: The expression of cadherin gene in a TSCC cell line with high metastatic potential (LN4) and the parental CAL27 were examined both in the TCGA database and in collected clinical samples, further verified by quantitative real-time PCR. The effects of CDH11 on the proliferation, apoptosis, migration, invasion and adhesion were tested in appropriate ways after CDH11 was overexpressed in TSCC cells. RESULTS: Among the 22 cadherin genes, CDH11 was one of the most obviously inhibited genes in LN4 cells as compared with the parental cells. Overexpression of CDH11 did not show a significant effect on cell proliferation, apoptosis, stemness, migration and invasion ability of TSCC cells themselves, but it increased the adhesion of TSCC cells with human oral epithelial cells and decreased their ability to pass through human oral epithelial cells (HOECs) for migration. CONCLUSION: The results indicated that CDH11 plays as a tumor suppressor in tongue squamous cell carcinoma by inhibiting the invasion and migration of tongue cancer cells. CDH11 may serve as an effective clinical target for new tongue cancer treatments.

[Effect of moxibustion on cardiac function and expression of autophagy-related proteins of cardiomyocytes in chronic heart failure rats].

OBJECTIVE: To observe the effect of moxibustion on cardiac function and expression of myocardial tumor suppressor protein p53, mammalian target of rapamycin (mTOR) and phosphorylated(p)-mTOR (excessive autophagy-associated proteins of cardiomyocytes) in rats with chronic heart failure (CHF), so as to explore its mechanisms underlying improvement of CHF. METHODS: SD rats were divided into blank control (n＝11), model(n＝8), autophagy activator (n＝8), autophagy inhibitor (n＝9) and moxibustion(n＝9) groups. The CHF model was established by i．p. injection of Doxorubicin Hydrochloride (DOX, 1 mg/mL, 1-4 mg/kg) every other day. Moxibustion was applied to bilateral "Feishu" (BL13) and "Xinshu" (BL15) for 20 min, 5 times a week for 3 weeks. Rats of the autophagy activator group received gavage of Rapamycin (RAPA, 2 mg/kg) and those of the autophagy inhibitor group received i．p. injection of Methyladenine (3-MA, 15 mg/kg) 5 times a week for 3 weeks after successful modeling. The heart weight and body weight were measured to calculate heart mass index (HW/BW＝heart weight ÷ body weight). Cardiac output (CO) and heart rate (HR) were measured by using a cardiac function meter. Serum N-terminal pro-brain natriuretic peptide (NT-pro BNP) content was assayed by using ELISA, and the expression of myocardial p53, p-mTOR and mTOR proteins was examined by Western blot. RESULTS: (1) Compared with the blank control group, the HR, HW/BW, NT-pro BNP content and p53 expression levels were significantly increased (P<0.01), and the CO and ratio of p-mTOR/mTOR were significantly decreased in the model group (P<0.01). (2) Compared with the model group, the HR, HW/BW and NT-pro BNP content of the autophagy inhibitor and moxibustion groups were significantly decreased (P<0.01, P<0.05), and CO and p-mTOR/mTOR ratio were significantly increased in both autophagy inhibitor and moxibustion groups (P<0.01). (3) Compared with the autophagy activator group, the levels of HR, HW/BW, NT-pro BNP and p53 in the autophagy inhibitor and moxibustion groups were significantly lower (P<0.01), and those of CO and p-mTOR/mTOR levels were significantly higher (P<0.01). CONCLUSION: Moxibustion, similar to the autophagy inhibitor, has a protective action on myocardium in CHF rats, which is possible by preventing over expression of myocardial autophagy-associated proteins during CHF.

[Acupuncture combined with opioid drugs on moderate and severe cancer pain: a randomized controlled trial].

OBJECTIVE: To explore the clinical therapeutic effect of acupuncture combined with opioid drugs on moderate and severe cancer pain. METHODS: A total of 60 patients with cancer were randomized into an observation group and a control group, 30 cases in each group. Oxycodonehydrochloride prolonged-release tablet was taken orally in the control group. On the basis of the control group, acupuncture was applied at Hegu (LI 4), Neiguan (PC 6), Zusanli (ST 36), Sanyinjiao (SP 6), etc. Corresponding back-shu points, xi-cleft points and ashi points were selected additionally according to primary viscera and pain sites in the observation group. The treatment was given once a day for 2 weeks. Symptomatic and supportive treatment were implanted, and no other antalgic measures were given during the trial. The daily dosage of opioid drug and the adverse reactions were recorded in both groups. Karnofsky performance status (KPS) and quality of life (QOL) scale scores were compared before and after treatment. Numerical rating scale (NRS) score was calculated to evaluate the clinical therapeutic effect. RESULTS: Compared before treatment, the daily dosage of opioid drugs after treatment was obviously reduced in the observation group (P<0.01), and was obviously increased in the control group (P<0.05). The dosage of opioid drugs after treatment in the observation group was much less than the control group (P<0.01). After treatment, the KPS and QOL scores were increased in both groups (P<0.01), and the scores in the observation group were superior to the control group (P<0.01, P<0.05). The analgesic effective rate was 90.0% (27/30) in the observation group, which was superior to 76.7% (23/30) in the control group (P<0.05). The adverse reactions rate in the observation group was lower than the control group (P<0.01). CONCLUSION: Acupuncture combined with opioid drugs can effectively relieve the cancer pain, improve the performance status and quality of life in cancer patients, reduce the dosage of opioid drugs and adverse reactions rate.

Quantification of testicular fat deposition in the evaluation of middle-aged overweight male infertility.

OBJECTIVES: To measure the testicular volume and testicular fat deposition of middle-aged overweight men and to assess the utility of testicular fat deposition and testicular volume in determining and monitoring testicular infertility. MATERIALS AND METHODS: Pelvic MRI with thin slice T2WI, T1WI and mDIXON Quant was performed on 30 middle-aged overweight patients in the treatment group and 30 middle-aged overweight men in the control group. Testicular volume and testicular fat deposition were measured separately based on thin slice T2WI and the fat fraction (FF) map of mDIXON Quant, and the testicular fat deposition observed with T1WI was used as a reference for qualitative diagnosis. Testicular volume and testicular fat deposition in middle-aged overweight individuals were compared using a t test with Bonferroni correction and receiver operating characteristic (ROC) curve. RESULTS: The testicular volumes (10.6-17.9 cm3) of individuals in the treatment group were smaller than those (12.6-19.0 cm3) of individuals in the control group (p < 0.05), and the average FF value (2.2-4.6%) of the testes in the treatment group was higher than that (1.5-3.1%) in the control group (p < 0.05). The ROC analysis showed that the area under the curve (AUC) of testicular fat deposition (0.899) was higher than that of testicular volume (0.777), and biopsy and sperm count were used as references to diagnose infertility. The diagnostic sensitivity (90.00%) of testicular fat deposition of the mDIXON Quant sequence was higher than that (50.00%) of the T1W sequence (p < 0.05). Testicular fat deposition was decreased after 6 months of active treatment with exercise weight loss and drug treatment, and no significant change in testicular volume was observed 6 months later. CONCLUSION: The findings suggest that the proton density fat fraction (mDIXON Quant sequence in this study) approach is a novel tool for the quantitative and objective evaluation of testicular fat deposition. Testicular fat deposition measurement is more specific than testicular volume measurement in the diagnosis of male infertility, and the mDIXON Quant is more sensitive than T1WI in the diagnosis of testicular fat deposition. Furthermore, our findings may facilitate a more accurate diagnosis and monitoring of testicular infertility, therapeutic effect, and prognosis by measuring testicular fat deposition.

Cloning, expression, and characterization of three ribosomal protein S13 genes in Sophora flavescens / Clonagem, expressão e caracterização de três proteínas ribossômicas S13 genes em Sophora flavescens

To characterize the structure and function of ribosomal protein S13 (RPS13), we identified fulllength open reading frames (ORFs) of three RPS13 genes (RPS13-1, RPS13-2, and RPS13-3) of the Chinese medicinal plant, Sophora flavescens. The target genes were amplified by reverse transcription-olymerase chain reaction (RT-PCR), ligated into the pET22b(+) vector, and then transformed into Escherichia coli BL21 competent cells for protein expression. The physicochemical properties, protein motif, evolution, and structural organization of the three RPS13 genes were analyzed using bioinformatics tools. The full-length ORFs (453 bp) of the three RPS13 genes of S. flavescens were cloned, and each encodes a protein of 151 amino acids in length, and their expression was detected by Western blotting. Bioinformatics analysis showed that RPS13s are stable proteins that are closely related to the 40S RPS13s of Vigna radiate var. radiate. Their three-dimensional structures included three -helices at the C-terminal and four -helices at the N-terminal, and the two clusters of helices were connected by a long random coil, which may help maintain the dynamic bridging interactions between the large and small subunits of the ribosome. The full-length ORFs of three RPS13 genes of S. flavescens were successfully cloned and expressed in vitro. The study of the physicochemical properties, evolution, and secondary and three-dimensional structures of the three proteins will provide the theoretical basis for further studies on the function of RPS13s in plants.

Objetivo: Para caracterizar a estrutura e a função da proteína ribossomal S13 (RPS13), identificamos fases de leitura abertas (ORFs) completas de três genes RPS13 (RPS13-1, RPS13-2 e RPS13-3) da planta medicinal chinesa, Sophora flavescens. Métodos: Os genes alvo foram amplificados por reação em cadeia da polimerase por transcrição reversa (RT-PCR), ligados ao vetor pET22b(+), e então transformados em células competentes de Escherichia coli BL21 para expressão protéica. As propriedades físico-químicas, o motivo protéico, a evolução e a organização estrutural dos três genes RPS13 foram analisados utilizando ferramentas de bioinformática. Resultados: ORFs completos (453 pb) dos três genes RPS13 de S. flavescens foram clonados, e cada um codifica uma proteína de 151 aminoácidos de comprimento, e sua expressão foi detectada por western blotting. A análise de bioinformática mostrou que as RPS13s são proteínas estáveis que estão intimamente relacionadas com as 40S RPS13s de Vigna radiata var. radiate. Suas estruturas tridimensionais incluíam três -hélices no C-terminal e quatro -hélices no N-terminal, e os dois aglomerados de hélices eram conectados por uma longa bobina aleatória, o que pode ajudar a manter as interações de ponte dinâmicas entre o subunidades grandes e pequenas do ribossomo. Conclusões: As ORFs completas de três genes RPS13 de S. flavescens foram clonadas e expressas com sucesso in vitro. O estudo das propriedades físico-químicas, evolução e estruturas secundárias e tridimensionais das três proteínas fornecerão a base teórica para estudos adicionais sobre a função das RPS13s em plantas.

[Effects of Moxibustion on Ventricular Mass Index and Expression of Apoptosis Related Proteins in Myocardium of Rats with Chronic Heart Failure].

OBJECTIVE: To observe the effect of moxibustion on cardiac function and the expression of B-cell lymphoma-2 (Bcl-2), Bcl-2 associated X (Bax), Fas, Fas ligand (FasL) in cardiomyocytes of chronic heart failure (CHF) rats, so as to explore its underlying mechanisms in preventing and treating CHF. METHODS: SD rats were randomly divided into normal control, model, moxibustion, Captopril and moxibustion ＋ Captopril (M＋C) groups (n＝12 rats/group). The CHF model was established by intraperitoneal injection of Adriamycin (ADR, from 1 to 4 mg/kg, once every other day for 15 days). Mild moxibustion was applied to bilateral"Feishu"(BL 13) and "Xinshu"(BL 15). Rats of the Captopril group was treated by gavage of Captopril suspension (5 mg/mL, 25 mL/kg), and those of the M＋C group treated by the combined two methods. All the treatments were given once a day for 3 weeks. The general conditions and behaviors of rats were observed. The left ventricular mass index (LVMI) and right ventricular mass index (RVMI) were detected for assessing the cardiac performance. Morphological changes of myocardium were observed by HE staining. Enzyme linked immunosorbent assay (ELISA) was used to detect the concentrations of B-type natriuretic peptide (BNP) and precursor N-terminal pro-brain natriuretic peptide (NT-pro BNP) in the serum. The expression levels of Bcl-2, Bax, Fas and FasL of the left ventricle of heart were detected by Western blot. RESULTS: After modeling, the pathological changes of myocardium (as myocardial cell swelling with vacuoles, myocardial fibre breakage, etc.) were obvious, the LVMI, RVMI, serum BNP and NT-pro BNP concentrations, and myocardial Bax, Fas and FasL protein expression levels were significantly increased in the model group compared with the normal group (P<0.01), while the expression level of Bcl-2 was significantly down-regulated (P<0.01). Following the interventions, the myocardial injury was reduced, both LVMI and RVMI, serum BNP concentration and Bax, Fas and FasL expression levels in the three treatment groups, and serum NT-pro BNP concentration in the moxibustion and M＋C groups were significantly decreased (P<0.05, P<0.01), while the myocardial Bcl-2 protein levels in the three treatment groups were significantly increased relevant to the model group (P<0.01). Comparison among the three treatment groups showed that the effects of moxibustion ＋ Captopril were significantly superior to those of simple moxibustion and simple Captopril in suppressing CHF-induced increased expression of myocardial Bax, Fas and FasL, and in lessening CHF-induced decrease of Bcl-2 level (P<0.05, P<0.01). No significant differences were found among the three treatment groups in down-regulating LVMI and RVMI, and serum BNP content (P>0.05)．. CONCLUSION: Moxibustion can reduce myocardial injury and improve cardiac function in CHF rats, which may be related to its effects in down-regulating the expression of myocardial Bax, Fas and FasL proteins, and up-regulating the expression of Bcl-2 protein to inhibit cardiomyocyte apoptosis.

The Effect of ICOS Polymorphism Interactions with HBV Mutations on HBV Subtype Infection Outcomes.

INTRODUCTION AND AIM: Hepatitis B virus (HBV) infection remains a public health problem worldwide. In addition, HBV infection results are influenced by various virological, immunological, and genetic factors. Inducible T-cell costimulator (ICOS) polymorphisms involving chronic HBV infection have been confirmed in previous studies. This study was to explore the effects of ICOS single nucleotide polymorphisms in HBV subtypes and their interactions with viral mutations on HBV infection outcomes. MATERIAL AND METHODS: A total of 1,636 Han Chinese individuals were recruited, including 47 asymptomatic HBV carriers (ASC), 353 chronic hepatitis B (CHB) patients, 327 HBV-related liver cirrhosis (LC) patients, 193 HBV-related hepatocellular carcinoma (HCC) patients, 464 patients with spontaneous recovery from HBV infection (SR), and 252 healthy controls (HC). DNA samples from these subjects were genotyped for four ICOS SNPs (rs11883722, rs10932029, rs1559931, and rs4675379). Direct sequencing was used to determine the HBV mutations in the enhancer II, basal core promoter, and pre-core regions. RESULTS: We found that the genotype "TC" of ICOS rs10932029 SNP was associated with decreased HBV-related LC risk in the genotype C group. Additionally, the A1762T, G1764A and A1762T/G1764A mutations were associated with an increased risk of LC in the genotype C group. Further study indicated that interactions between ICOS rs10932029 genotype "TC" and A1762T or A1762T/G1764A mutations significantly decreased the LC risk in the genotype C group. CONCLUSION: The rs10932029 genotype "TC" might be an LC-protective factor for HBV genotype C infection. The interactions between the rs10932029 genotype "TC" and A1762T or A1762T/G1764A mutations could decrease the risk of LC.

Retinoid X Receptor α-Dependent HBV Minichromosome Remodeling and Viral Replication.

BACKGROUND AND AIM: The HBV covalently closed circular DNA (cccDNA) is organized into a minichromosome in the nuclei of infected hepatocytes through interactions with histone and nonhistone proteins. Retinoid X receptor α (RXRα), a liver-enriched nuclear receptor, participates in regulation of HBV replication and transcription through modulation of HBV enhancer 1 and core promoter activity. MATERIAL AND METHODS: This study investigated RXRα involvement in HBV cccDNA epigenetic modifications. Quantitative cccDNA chromatin immunoprecipitation (ChIP) was applied to study the recruitment of RXRα, histones, and chromatin-modifying enzymes to HBV minichromosome in HepG2 cells after transfection of the linear HBV genome. RESULTS: RXRα Was found to directly bind to HBV cccDNA; recruitment of RXRα to HBV mini-chromosome paralleled HBV replication, histone recruitment, and histone acetylation in HBVcccDNA. Moreover, RXRα overexpression or knock-down significantly increased or impaired the recruitment of the p300 acetyltransferase to cccDNAminichromosome. CONCLUSIONS: Our results confirmed the regulation of RXRα on HBV replication in vitro and demonstrated the modulation of RXRα on HBV cccDNA epigenetics. These findings provide a profound theoretical and experimental basis for late-model antiviral treatment acting on the HBV cccDNA and minichromosome.

Association of genetic polymorphisms in CD8+ T cell inhibitory genes and susceptibility to and progression of chronic HBV infection.

BACKGROUND: Previous studies have shown that multiple inhibitory genes play an important role in HBV-specific CD8+ T cell exhaustion and dysfunction in the setting of chronic HBV infection. Polymorphic variants of these genes are thought to be predisposing factors for HBV susceptibility, clearance, and disease progression. The aim of this retrospective study was to identify variants affecting chronic HBV infection in a Chinese Han population. METHODS: We chose 28 tgSNPs from HapMap data on 5 key genes. They were genotyped on a total of 858 chronic HBV patients, 429 patients who underwent spontaneous recovery, and 239 healthy controls. We evaluated the correlation between the polymorphisms and HBV susceptibility, spontaneous clearance, and disease progression. RESULTS: The association of rs3827537 of BIM genotype TA and allele A was significantly different (P=0.016, OR=2.049; P=0.031, OR=1.925) between HBV patients and healthy controls. The rs36084323 of PD-1, as well as rs3766377, rs485618, rs4656942 of CD244 showed significant associations with the risk for HBV-related cirrhosis and hepatocellular carcinoma (HCC) (P=0.009, OR=0.482; P=0.009, OR=4.573; P=0.015, OR=0.580; P=0.028, OR=2.855). MDR analysis revealed that the four SNPs (rs36084323, rs3766377, rs485618, rs4656942) modulated the predisposition to cirrhosis and HCC in patients with chronic HBV infection (P=0.006). Using a luciferase reporter assay, we demonstrated that various alleles of rs3766377 had differential effects, and rs3766377 and rs485618 might have interactive effects. CONCLUSIONS: The present study reveals genetic associations among PD-1 and CD244 variants that may be involved in the development of cirrhosis and HCC in patients with chronic HBV infection. The BIM variant was associated with HBV susceptibility.

[EPCAM-positive normal hepatic progenitor cells transformation into liver stem cells and HBx-mediated effects on stability in adult mouse].

OBJECTIVE: To investigate the transformative potential of hepatic progenitor cells to differentiate into liver stem cells using a normal adult mouse system and to determine the effects of HBx protein in these liver stem cells' differentiation into hepatic cells. METHODS: Hepatic progenitor cells were obtained from mice by means of an optimized two-step digestion and perfusion method followed by joint differential centrifugation and density gradient centrifugation. Transformation of the hepatic progenitor cells into liver stem cells was observed by immunofluorescent detection of CD 133, EPCAM, CD49f and CK19. Differentiation of the resultant liver stem cells into hepatic cells and bile duct epithelial cells was observed after DMSO addition by Periodic Acid-Schiff (PAS) staining followed by cell immunofluorescence and flow cytometry. To determine the effects of HBx on these liver stem cells' ability to differentiate into hepatic cells, cell transfection was used followed by observation of morphology and proliferation capacity. RESULTS: Cell viability of the isolated hepatic progenitor cells was 78.67+/-4.04%. Stimulation with EGF and collagen led to growth of some of the paving-stone shaped cells attached to the hepatic progenitor cells which had gathered into spherical clumps, as is the nature of stem cells. The liver stem cells showed high expression of CD133, CD49f and CK19, and low expression of EPCAM. Under the effect of DMSO, the liver stem cells differentiated into hepatocytes and bile duct epithelial cells. After HBx transfecfion, the liver stem cells maintained the characteristic shape of stem cells and showed enhanced proliferation. CONCLUSION: EPCAM-positive adult hepatic progenitor cells can transform into liver stem cells.The HBx protein may play an important role in maintaining the stability of liver stem cells in the adult mouse.

Phenotypic assay of a hepatitis B virus strain carrying an rtS246T variant using a new strategy.

Phenotypic assays of hepatitis B virus (HBV) play an important role in research related to the problem of drug resistance that emerges during long-term nucleot(s)ide therapy in patients with chronic hepatitis B. Most of the phenotypic assay systems that are available currently rely on the transfection of recombinant replication-competent HBV DNA into hepatoma cell lines. Cloning clinical HBV isolates using conventional digestion-and-ligation techniques to generate replication-competent recombinants can be very difficult because of the sequence heterogeneity and unique structure of the HBV genome. In this study, a new strategy for constructing an HBV 1.1× recombinant was developed. The core of this strategy is the "fragment substitution reaction" (FSR). FSR allows PCR fragments to be cloned without digestion or ligation, providing a new tool for cloning fragments or genomes amplified from serum HBV DNA, and therefore making the assay of HBV phenotypes more convenient. Using this strategy, a phenotypic assay was performed on an HBV strain carrying an rtS246T variant isolated from a patient with chronic hepatitis B that was only responsive partially to entecavir therapy. The results indicated that this strain is sensitive to entecavir in vitro.

A new strategy for constructing in vitro replication-competent 1.3 copies of hepatitis B virus genome.

In the absence of a robust infectable cell culture system, assays related to replication of clinical HBV isolates are based on the transfection of replication-competent HBV DNA into hepatoma cell lines that are able to replicate and secrete HBV virions. Current methods for constructing HBV 1.1 genomes work well for drug susceptibility assays, but are not very suitable for research on HBV replication capacity or regulation since a heterogeneous promoter is required to drive pgRNA transcription. A new strategy for constructing HBV 1.3 genomes that contain HBV intrinsic promoter necessary for pgRNA transcription is reported in this paper. Using this strategy, three HBV 1.3 genomes from isolates of three patients were constructed. When the three HBV 1.3 genomes were transfected into the HepG2 cell line, replicative intermediates were detectable by Southern blotting with digoxigenin-labeled DNA probe in two of the three constructs. Using overlap extension PCR and avoiding as much as possible the digestion-and-ligation process, this strategy could be applied to constructing longer-than-genome units for most genotypes of HBV strains.