ISG12a promotes immunotherapy of HBV-associated hepatocellular carcinoma through blocking TRIM21/AKT/β-catenin/PD-L1 axis

Hepatitis B virus (HBV) infection generally elicits weak type-I interferon (IFN) immune response in hepatocytes, covering the regulatory effect of IFN-stimulated genes. In this study, low level of IFN-stimulated gene 12a (ISG12a) predicted malignant transformation and poor prognosis of HBV-associated hepatocellular carcinoma (HCC), whereas high level of ISG12a indicated active NK cell phenotypes. ISG12a interacts with TRIM21 to inhibit the phosphorylation activation of protein kinase B (PKB, also known as AKT) and β-catenin, suppressing PD-L1 expression to block PD-1/PD-L1 signaling, thereby enhancing the anticancer effect of NK cells. The suppression of PD-1-deficient NK-92 cells on HBV-associated tumors was independent of ISG12a expression, whereas the anticancer effect of PD-1-expressed NK-92 cells on HBV-associated tumors was enhanced by ISG12a and treatments of atezolizumab and nivolumab. Thus, tumor intrinsic ISG12a promotes the anticancer effect of NK cells by regulating PD-1/PD-L1 signaling, presenting the significant role of innate immunity in defending against HBV-associated HCC.

PZR suppresses innate immune response to RNA viral infection by inhibiting MAVS activation in interferon signaling mediated by RIG-I and MDA5

RNA viral infections seriously endanger human health. Src homology 2 (SH2) domain-containing protein tyrosine phosphatase 2 (SHP2) suppresses innate immunity against influenza A virus, and pharmacological inhibition of SHP2 provokes hepatic innate immunity. SHP2 binds and catalyzes tyrosyl dephosphorylation of protein zero-related (PZR), but the regulatory effect of PZR on innate immune response to viral infection is unclear. In this study, the transcription and protein level of PZR in host cells were found to be decreased with RNA viral infection, and high level of PZR was uncovered to inhibit interferon (IFN) signaling mediated by RIG-I and MDA5. Through localizing in mitochondria, PZR targeted and interacted with MAVS (also known as IPS-1/VISA/Cardif), suppressing the aggregation and activation of MAVS. Specifically, Y263 residue in ITIM is critical for PZR to exert immunosuppression under RNA viral infection. Moreover, the recruited SHP2 by PZR that modified with tyrosine phosphorylation under RNA viral infection might inhibit phosphorylation activation of MAVS. In conclusion, PZR and SHP2 suppress innate immune response to RNA viral infection through inhibiting MAVS activation. This study reveals the regulatory mechanism of PZR-SHP2-MAVS signal axis on IFN signaling mediated by RIG-I and MDA5, which may provide new sight for developing antiviral drugs.

Establishment of cell culture model and humanized mouse model of chronic hepatitis B virus infection

IMPORTANCE

Approximately 257 million people worldwide have been infected with hepatitis B virus (HBV), and HBV infection can cause chronic hepatitis, cirrhosis, and even liver cancer. The lack of suitable and effective infection models has greatly limited research in HBV-related fields for a long time, and it is still not possible to discover a method to completely and effectively remove the HBV genome. We have constructed a hepatocellular carcinoma cell line, HLCZ01, that can support the complete life cycle of HBV. This model can mimic the long-term stable infection of HBV in the natural state and can replace primary human hepatocytes for the development of human liver chimeric mice. This model will be a powerful tool for research in the field of HBV.

Helicobacter pylori CagA promotes immune evasion of gastric cancer by upregulating PD-L1 level in exosomes

Cytotoxin-associated gene A (CagA) of Helicobacter pylori (Hp) may promote immune evasion of Hp-infected gastric cancer (GC), but potential mechanisms are still under explored. In this study, the positive rates of CagA and PD-L1 protein in tumor tissues and the high level of exosomal PD-L1 protein in plasma exosomes were significantly associated with the elevated stages of tumor node metastasis (TNM) in Hp-infected GC. Moreover, the positive rate of CagA was positively correlated with the positive rate of PD-L1 in tumor tissues and the level of PD-L1 protein in plasma exosomes, and high level of exosomal PD-L1 might indicate poor prognosis of Hp-infected GC. Mechanically, CagA increased PD-L1 level in exosomes derived from GC cells by inhibiting p53 and miRNA-34a, suppressing proliferation and anticancer effect of CD8+ T cells. This study provides sights for understanding immune evasion mediated by PD-L1. Targeting CagA and exosomal PD-L1 may improve immunotherapy efficacy of Hp-infected GC.

Carboxypeptidase A4 negatively regulates HGS-ETR1/2-induced pyroptosis by forming a positive feedback loop with the AKT signalling pathway

Pyroptosis, a mode of inflammatory cell death, has recently gained significant attention. However, the underlying mechanism remains poorly understood. HGS-ETR1/2 is a humanized monoclonal antibody that can bind to DR4/5 on the cell membrane and induce cell apoptosis by activating the death receptor signalling pathway. In this study, by using morphological observation, fluorescence double staining, LDH release and immunoblot detection, we confirmed for the first time that HGS-ETR1/2 can induce GSDME-mediated pyroptosis in hepatocellular carcinoma cells. Our study found that both inhibition of the AKT signalling pathway and silencing of CPA4 promote pyroptosis, while the overexpression of CPA4 inhibits it. Furthermore, we identified a positive regulatory feedback loop is formed between CPA4 and AKT phosphorylation. Specifically, CPA4 modulates AKT phosphorylation by regulating the expression of the AKT phosphatase PP2A, while inhibition of the AKT signalling pathway leads to a decreased transcription and translation levels of CPA4. Our study reveals a novel mechanism of pyroptosis induced by HGS-ETR1/2, which may provide a crucial foundation for future investigations into cancer immunotherapy.

Activation of AIM2 by hepatitis B virus results in antiviral immunity that suppresses hepatitis C virus during coinfection

IMPORTANCE

Clinical data suggest that Hepatitis C virus (HCV) levels are generally lower in Hepatitis B virus (HBV) co-infected patients, but the mechanism is unknown. Here, we show that HBV, but not HCV, activated absent in melanoma-2. This in turn results in inflammasome-mediated cleavage of pro-IL-18, leading to an innate immune activation cascade that results in increased interferon-γ, suppressing both viruses.

The dual functions of KDM7A in HBV replication and immune microenvironment

KDM7A (lysine demethylase 7A, also known as JHDM1D) is a histone demethylase, it is mainly involved in the intracellular post-translational modifications process. Recently, it has been proved that the histone demethylase members can regulate the replication of hepatitis B virus (HBV) and the expression of key molecules in the Janus-activated kinase-signal transducer and activator of the transcription (JAK/STAT) signaling pathway by chromatin modifying mechanisms. In our study, we identify novel roles of KDM7A in HBV replication and immune microenvironment through two subjects: pathogen and host. On the one hand, KDM7A is highly expressed in HBV-infected cells and promotes HBV replication in vitro and in vivo. Moreover, KDM7A interacts with HBV covalently closed circular DNA and augments the activity of the HBV core promoter. On the other hand, KDM7A can remodel the immune microenvironment. It inhibits the expression of interferon-stimulated genes (ISGs) through the IFN-γ/JAK2/STAT1 signaling pathway in both hepatocytes and macrophages. Further study shows that KDM7A interacts with JAK2 and STAT1 and affects their methylation. In general, we demonstrate the dual functions of KDM7A in HBV replication and immune microenvironment, and then we propose a new therapeutic target for HBV infection and immunotherapy. IMPORTANCE Histone lysine demethylase KDM7A can interact with covalently closed circular DNA and promote the replication of hepatitis B virus (HBV). The IFN-γ/JAK2/STAT1 signaling pathway in macrophages and hepatocytes is also downregulated by KDM7A. This study provides new insights into the mechanism of HBV infection and the remodeling of the immune microenvironment.

Regulation of PKR-dependent RNA translation inhibition by TRIM21 upon virus infection or other stress

The host always employs various ways to defend against viral infection and spread. However, viruses have evolved their own effective strategies, such as inhibition of RNA translation of the antiviral effectors, to destroy the host's defense barriers. Protein synthesis, commonly controlled by the α-subunit of eukaryotic translation initiation factor 2 (eIF2α), is a basic cellular biological process among all species. In response to viral infection, in addition to inducing the transcription of antiviral cytokines by innate immunity, infected cells also inhibit the RNA translation of antiviral factors by activating the protein kinase R (PKR)-eIF2α signaling pathway. Regulation of innate immunity has been well studied; however, regulation of the PKR-eIF2α signaling pathway remains unclear. In this study, we found that the E3 ligase TRIM21 negatively regulates the PKR-eIF2α signaling pathway. Mechanistically, TRIM21 interacts with the PKR phosphatase PP1α and promotes K6-linked polyubiquitination of PP1α. Ubiquitinated PP1α augments its interaction with PKR, causing PKR dephosphorylation and subsequent translational inhibition release. Furthermore, TRIM21 can constitutively restrict viral infection by reversing PKR-dependent translational inhibition of various previously known and unknown antiviral factors. Our study highlights a previously undiscovered role of TRIM21 in regulating translation, which will provide new insights into the host antiviral response and novel targets for the treatment of translation-associated diseases in the clinic.

Exosomal PD‑L1 promotes the formation of an immunosuppressive microenvironment in gastric diffuse large B‑cell lymphoma

Gastric diffuse large B‑cell lymphoma (GDLBCL) is a common disease with an increasing incidence. However, the regulatory effect of exosomal programmed death‑ligand 1 (PD‑L1) on the immune microenvironment in GDLBCL is unclear. In the present study, the protein expression levels of exosomal PD‑L1 in the supernatants of cultured diffuse large B‑cell lymphoma (DLBCL) cells and the plasma of patients with GDLBCL was assessed using immunoblotting. Exosomes derived from DLBCL cells were cocultured with T lymphocytes or injected into tumor xenograft mice by tail vein injection. The relationship between the protein expression level of exosomal PD‑L1 in the plasma and the clinical characteristics and immune microenvironmental parameters of GDLBCL was evaluated using immunoblotting and immunohistochemistry. High levels of exosomal PD‑L1 were found in the supernatants of cultured DLBCL cells. Exosomes with high levels of PD‑L1 promoted growth of tumors formed by DLBCL cells in vivo and inhibited the proliferation of T lymphocytes. Notably, the protein expression level of PD‑L1 in plasma exosomes derived from GDLBCL patients was significantly higher than that of healthy individuals. High levels of PD‑L1 in plasma exosomes were significantly associated with international prognostic index score, pathological type and advanced Lugano stage, which might lead to the poor prognosis of GDLBCL. Moreover, a high level of PD‑L1 in plasma exosomes was significantly associated with an immunosuppressive microenvironment in GDLBCL. Therefore, the results of the present study indicated that exosomal PD‑L1 inhibited the proliferation of T lymphocytes and promoted the formation of an immunosuppressive microenvironment in GDLBCL. High expression of exosomal PD‑L1 may suggest a poor prognosis of GDLBCL, and exosomal PD‑L1 in plasma may be a new diagnostic indicator for GDLBCL.

[Mechanisms mediating the inhibitory effects of quercetin against phthalates-induced testicular oxidative damage in rats]

OBJECTIVE

To explore the mechanism underlying the inhibitory effect of quercetin against testicular oxidative damage induced by a mixture of 3 commonly used phthalates (MPEs) in rats.

METHODS

Forty male Sprague-Dawley rats were randomly divided into control group, MPEs exposure group, and MPEs with low-, median- and high-dose quercetin treatment groups. For MPEs exposure, the rats were subjected to intragastric administration of MPEs at the daily dose of 900 mg/kg for 30 consecutive days; Quercetin treatments were administered in the same manner at the daily dose of 10, 30, and 90 mg/kg. After the treatments, serum levels of testosterone, luteinizing hormone (LH), follicle stimulating hormone (FSH), and testicular malondialdeyhde (MDA), catalase (CAT) and superoxide dismutase (SOD) were detected, and testicular pathologies of the rats were observed with HE staining. The expressions of nuclear factor-E2-related factor 2 (Nrf2), Kelch-like ECH2 associated protein 1 (Keap1) and heme oxygenase 1 (HO-1) in the testis were detected using immunofluorescence assay and Western blotting.

RESULTS

Compared with the control group, the rats with MPEs exposure showed significant reductions of the anogenital distance, weight of the testis and epididymis, and the coefficients of the testis and epididymis with lowered serum testosterone, LH and FSH levels (P < 0.05). Testicular histological examination revealed atrophy of the seminiferous tubules, spermatogenic arrest, and hyperplasia of the Leydig cells in MPEs-exposed rats. MPEs exposure also caused significant increments of testicular Nrf2, MDA, SOD, CAT and HO-1 expressions and lowered testicular Keap1 expression (P < 0.05). Treatment with quercetin at the median and high doses significantly ameliorated the pathological changes induced by MPEs exposure (P < 0.05).

CONCLUSION

Quercetin treatment inhibits MPEs-induced oxidative testicular damage in rats possibly by direct scavenging of free radicals to lower testicular oxidative stress and restore the regulation of the Nrf2 signaling pathway.

TRIM21 Regulates Virus-Induced Cell Pyroptosis through Polyubiquitination of ISG12a

Pyroptosis is a form of regulated cell death mediated by the gasdermin protein family. During virus infection, cell pyroptosis restricts viral replication. The mechanisms of the tripartite motif (TRIM) protein family and IFN-stimulated genes (ISGs) against viruses have been studied. The role of TRIMs and ISGs in pyroptosis remains unclear. In this study, we show that TRIM21 interacts with ISG12a in viral infection and facilitates its translocation into the mitochondria by promoting its ubiquitination, thereby causing caspase 3 activation. Gasdermin E (GSDME) is specifically cleaved by caspase 3 upon viral infection, releasing the GSDME N-terminal domain, perforating the cell membrane, and causing cell pyroptosis. Our study uncovers a new mechanism of TRIM21 and ISG12a in regulating virus-induced cell pyroptosis.

The redox cycling of STAT2 maintains innate immune homeostasis

Interferons (IFNs) are essential in antiviral defense, antitumor effects, and immunoregulatory activities. Although methionine oxidation is associated with various physiological and pathophysiological processes in plants, animals, and humans, its role in immunity remains unclear. We find that the redox cycling of signal transducer and activator of transcription 2 (STAT2) is an intrinsic cellular biological process, and that impairment of the redox status contributes to STAT2 methionine oxidation, inhibiting its activation. IFN protects STAT2 from methionine oxidation through the recruitment of methionine sulfoxide reductase MSRB2, whose enzymatic activity is enhanced by N-acetyltransferase 9 (NAT9), a chaperone of STAT2 defined in this study, upon IFN treatment. Consequently, loss of Nat9 renders mice more susceptible to viral infection. Our study highlights the key function of methionine oxidation in immunity, which provides evidence for the decline of immune function by aging and may provide insights into the clinical applications of IFN in immune-related diseases.

[Expert consensus on measurement and clinical application of serum HBV RNA in patients with chronic HBV infection]

Since the discovery of circulating hepatitis B virus (HBV) RNA in the peripheral blood of patients with chronic hepatitis B in 1996, a growing number of studies have focused on clarifying the biological characteristics and clinical application value of serum HBV RNA. This consensus mainly summarizes the research progress of serum HBV RNA existing profiles, quantitative detection methods, and current clinical applications. In order to better apply this indicator for the clinical management of patients with chronic HBV infection, recommendations on quantitative detection target regions, detection results, and clinical applications are put forward.

[Relationship between parental reproductive age and the risk of overweight and obesity in offspring]

Objective: To explore the role of parental reproductive age on the risk of overweight and obesity in offspring. Methods: The participants were derived from physical examination data of students aged 6-18 years in seven provinces in China, and questionnaire survey was used to collect demographic characteristics and lifestyle information of the students and their parents. A total of 41 567 children with complete data were included. According to the restricted cubic spline curve, maternal reproductive age was divided into three categories, 14-23, 24-28, and 29-38 years, and paternal reproductive age was divided into 14-23, 24-30, and 31-42 years. Multivariate logistic regression model was used to analyze the association between parental reproductive age and parental nutritional status and the risk of overweight and obesity in offspring. Results: The mean age of 41 567 children was (10.6±3.2) years, and the mean paternal and maternal age were (27.9±4.4) years and (25.8±4.0) years, respectively. The detection rate of overweight and obesity was 23.4%. After adjusting factors of children diet and behaviors, the OR(95%CI)of offspring overweight and obesity in groups of fathers aged 24-30 years and mothers aged 24-28 years was 1.11 (1.04-1.18) and 1.16 (1.08-1.24), respectively. When none parents were overweight and obese, the difference of obesity risk was not statistically significant. When both parents were overweight and obese, the OR(95%CI)of offspring overweight and obesity in groups of fathers aged 24-30 years and mothers aged 14-28 years old was 1.27 (1.00-1.62) and 1.33 (1.07-1.65) respectively. Conclusion: Parental reproductive age and parental overweight and obesity status may both increase the risk of overweight and obesity in offspring, with a significant interaction effect.

Visfatin facilitates gastric cancer malignancy by targeting snai1 via the NF-κB signaling

BACKGROUND

Visfatin acts as an oncogenic factor in numerous tumors through a variety of cellular processes. Visfatin has been revealed to promote cell migration and invasion in gastric cancer (GC). Snai1 is a well-known regulator of EMT process in cancers. However, the relationship between visfatin and snai1 in GC remains unclear. The current study aimed to explore the role of visfatin in GC.

METHODS

The RT-qPCR and western blot analysis were used to measure RNA and protein levels, respectively. The cell migration and invasion were tested by Trans-well assays and western blot analysis.

RESULTS

Visfatin showed upregulation in GC cells. Additionally, Visfatin with increasing concentration facilitated epithelial-mesenchymal transition (EMT) process by increasing E-cadherin and reducing N-cadherin and Vimentin protein levels in GC cells. Moreover, endogenous overexpression and knockdown of visfatin promoted and inhibited migratory and invasive abilities of GC cells, respectively. Then, we found that snai1 protein level was positively regulated by visfatin in GC cells. In addition, visfatin activated the NF-κB signaling to modulate snai1 protein expression. Furthermore, the silencing of snai1 counteracted the promotive impact of visfatin on cell migration, invasion and EMT process in GC.

CONCLUSION

Visfatin facilitates cell migration, invasion and EMT process by targeting snai1 via the NF-κB signaling, which provides a potential insight for the treatment of GC.

Maintenance treatment in advanced HER2-negative gastric cancer

Survival for patients with advanced gastric cancer (GC) remains poor. Systemic chemotherapy which has reached a plateau stays the standard first-line (1L) treatment for advanced human epidermal growth-factor receptor 2 (HER2)-negative GC. To maximize the benefit of 1L treatment, the concept of maintenance treatment is constantly being explored. In advanced HER2-negative GC, current clinical guidelines do not recommend a standard maintenance therapy strategy. In addition to the monotherapy maintenance with fluorouracil after 4-6 cycles of 1L chemotherapy, some agents that are active against novel targets have been evaluated in clinical trials for maintenance treatment. Whereas most of these trials do not reach their primary endpoints, they open new horizons for the 1L treatment of advanced HER2-negative GC. Therefore, we reviewed the clinical trials in the field of maintenance treatment in advanced HER2-negative GC and discussed some of the problems in clinical trials.

The innate immune effector ISG12a promotes cancer immunity by suppressing the canonical Wnt/β-catenin signaling pathway

The ability to harness innate immunity is a promising solution for improving cancer immunotherapy. Interferon (IFN) induces expression of IFN-stimulated genes (ISGs) by activating the JAK-STAT signaling pathway to promote innate immunity and inhibit malignant tumor growth, but the functions and mechanisms of most ISGs in cancer regulation are unknown. As an innate immune effector, ISG12a promotes the innate immune response to viral infection. In this study, ISG12a was found to be expressed at low levels in gastrointestinal cancer, represented by hepatocellular cancer (HCC) and gastric cancer (GC), and it identified as a tumor suppressor that affects clinical prognosis. ISG12a silencing accelerated the malignant transformation and epithelial-mesenchymal transition of cancer cells. Mechanistically, ISG12a promoted β-catenin proteasomal degradation by inhibiting the degradation of ubiquitinated Axin, thereby suppressing the canonical Wnt/β-catenin signaling pathway. Notably, β-catenin was identified as a transcription factor for PD-L1. Inhibition of Wnt/β-catenin signaling by ISG12a suppressed expression of the immune checkpoint PD-L1, rendering cancer cells sensitive to NK cell-mediated killing. This study reveals a mechanism underlying the anticancer effects of IFN. Some ISGs, as represented by ISG12a, may be useful in cancer therapy and prevention. The identified interrelations among innate immunity, Wnt/β-catenin signaling, and cancer immunity may provide new insight into strategies that will improve the efficiency of immunotherapy.

Vacuum Sealing Drainage Therapy for Refractory Infectious Wound on 16 Renal Transplant Recipients

BACKGROUND

Refractory infectious wounds on renal transplantation (RT) recipients significantly prolong hospital stay, increase medical costs, and threaten allograft survival. Vacuum sealing drainage (VSD) therapy is a new technique for managing wounds based on the principle of application of controlled negative pressure. The aim of this study was to summarize the efficacy and safety of VSD therapy in the management of refractory infectious wounds following RT.

MATERIALS AND METHODS

This is a retrospective study of a cohort of 661 consecutive patients who received renal transplants over a period of 3 years in which the data were collected and analyzed retrospectively.

RESULTS

Out of the 661 patients, 16 (2.4%) developed refractory wound infection following RT. Nineteen organisms were identified by culture from all patients, including 10 patients infected with 1 or more bacteria, 2 patients with fungal infection, and 4 patients with both. Specifically, mucormycosis was demonstrated in 4 patients, pan-resistant Klebsiella pneumoniae in 2 patients, and Acinetobacter baumannii in 2 patients. All 16 patients were treated with VSD therapy for a median of 37 days (range, 6-111 days). The number of VSD sets used ranged from 4 to 28 sets (mean, 11.1 sets). A combination of antibiotics, debridement, and VSD therapy lead to 100% (16 of 16) wound healing. No VSD-relevant adverse events were observed.

CONCLUSIONS

VSD therapy is an effective and safe adjunct to conventional treatment modalities for the management of refractory wound infection following RT.

Effect of Early Immunosuppression Therapy on De Novo Anti-Human-Leukocyte-Antigen Antibody After Kidney Transplantation

The aim of the study was to investigate the effect of immunosuppression therapy early after kidney transplantation, particularly exposure of mycophenolic acid (MPA) and calcineurin inhibitor (CNI), on posttransplantation de novo HLA antibody production.

METHODS

A single-center retrospective cohort study was performed at the First Affiliated Hospital of Sun Yat-sen University, enrolling the kidney transplant or pancreas-kidney transplant recipients who had surgery between January 2010 and February 2016.

RESULTS

A total of 214 recipients were included in the study with a median follow-up period of 1.06 years. A total of 30 recipients (14.0%) were positive in HLA antibody detection posttransplant with a median follow-up period of 1.46 years. Ten recipients (4.7%) lost their allograft function during follow-up, and 6 of them (60%) developed de novo HLA antibody after graft failure. Multivariate analysis showed that acute rejection significantly increased the risk of de novo HLA antibody (hazard ratio [HR], 2.732). Intensified MPA dosing therapy reduced the risk by 59.8% (HR, 0.402); low-dose CNI therapy increased the risk by 33.3% (HR, 1.333), and the effect of extremely low-dose CNI therapy was even larger (HR, 2.242).

CONCLUSION

The risk of de novo HLA antibody can be decreased by reducing the risk of acute rejection. A tendency was seen in low-dose CNI therapy to increase the risk of de novo HLA antibody, but intensified MPA dosing therapy may provide an umbrella protection effect by reducing the risk. Prospective study was required to confirm the effects.

Higher Incidence of Renal Allograft Glomerulonephritis in Living-Related Donor Kidney Transplantation

Glomerulonephritis recurrence has emerged as one of the leading causes of allograft loss. We aimed to investigate the effect of living-related and deceased donation on the incidence of renal allograft glomerulonephritis and its effect on renal allograft survival.

METHODS

Adult renal allograft recipients with primary glomerulonephritis were enrolled. Transplantation date was from Feb 2004 to Dec 2015. Exclusion criteria included combined organ transplantation, structural abnormality, diabetic nephropathy, hypertension nephropathy, obstructive nephropathy, and primary uric acid nephropathy. The incidence of biopsy-proven allograft glomerulonephritis was compared between the living-related donor group and the deceased donor group. Graft survival was assessed with Kaplan-Meier method, and Cox proportional hazard model was used to evaluate the effect of posttransplant glomerulonephritis on graft outcome.

RESULTS

There were 525 living-related donor kidney transplant recipients (LRKTx) and 456 deceased donor kidney transplant recipients (DDKTx) enrolled. The incidence of IgA nephropathy was 8.8% in the LRKTx group and 1.3% in the DDKTx group (P < .001); the incidence of focal segmental glomerulosclerosis (FSGS) was 3.8% in the LRKTx group and 1.5% in the DDKTx group (P = .03). FSGS increased the risk of graft failure compared with non-FSGS (hazard ratio [HR], 3.703 [1.459-9.397]; P = .006). IgA nephropathy increased the risk of graft failure by over 5 times 5 years after kidney transplantation compared with non-IgA nephropathy, but it did not affect early allograft survival (HR for ≥5 years, 6.139; 95% CI, 1.766-21.345; P = .004; HR for <5 years, 0.385 [0.053-2.814]; P = .35).

CONCLUSIONS

Higher incidence of IgA nephropathy and FSGS in renal allograft was observed in living-related donor kidney transplantation compared with deceased donor kidney transplantation. De novo or recurrent IgA nephropathy and FSGS impaired long-term renal allograft survival.

Recombinant beta interferon could clear the low-dose infected porcine reproductive and respiratory syndrome virus (PRRSV) in MARC-145 cells

Porcine reproductive and respiratory syndrome virus (PRRSV) causes one of the most economically devastating and pandemic porcine diseases. Previous study has shown that MARC-145 cells pretreated with recombinant IFN-β (rIFN-β) couldn't develop cytopathic effect (CPE) of PRRSV. However, up to date, it is not clear whether MARC-145 cells post-treated with rIFN-β could develop CPE of PRRSV. The present work showed that the MARC-145 cells didn't develop the CPE at 120 hr post-infection (p.i.) with low-dose of PRRSV when the cells were pre-treated with rIFN-β (Group 1), post-treated with rIFN-β at 4 hr p.i. (Group 2), or post-treated with rIFN-β at 8 hr p.i. (Group 3), while the MARC-145 cells could develop CPE when the cells were infected with high-dose PRRSV and then treated with rIFN-β at 24 hr p.i.. Furthermore, the indirect immunofluorescence assay confirmed that there were a few N protein-positive cells in the high-dose infected cells in Group 1, Group 2 and Group 3, while there were no N protein-positive cells in the low-dose infected cells in all rIFN-β treatment groups. In addition, the numbers of N protein-positive cells in high-dose infected cells (MOI = 10) in Group 1 were lower than that in Group 2 and Group 3. The results above demonstrated that both pre-treatment with rIFN-β and an earlier post-treatment with rIFN-β could inhibit the PRRSV replication and could clear the low-dose infected PRRSV, which indicated that the rIFN-β had efficient antiviral activities when the cells have been infected with PRRSV.

Dynamic effects of CYP3A5 polymorphism on dose requirement and trough concentration of tacrolimus in renal transplant recipients

WHAT IS KNOWN AND OBJECTIVE

Tacrolimus is a widely used immunosuppressive drug with marked pharmacokinetic variability partly due to CYP3A5 polymorphism. Our study aimed to investigate the dynamic effects of CYP3A5 genotypes on dose requirement and trough concentration (C₀ ) of tacrolimus in renal transplant recipients.

METHODS

A total of 194 Chinese renal transplant recipients received oral tacrolimus twice daily. Whole-blood C₀ of tacrolimus were measured on the 3rd day, 7th day, 14th day, 1st month, 3rd month and 6th month post-transplantation. CYP3A5 genotypes were determined and the recipients were categorized as CYP3A5 expressers (CYP3A5*1 allele carriers) and non-expressers (homozygous CYP3A5*3). The correlated serum creatinine, haematocrit and albumin were also detected.

RESULTS

The allele frequencies for CYP3A5*1/*1, *1/*3 and *3/*3 were 7·7%, 44·8% and 47·4%, respectively. There were no significant variability in serum creatinine, haematocrit and albumin values between CYP3A5 expressers and non-expressers. Larger doses were administered to CYP3A5 expressers than to non-expressers after surgery except the initial dose. C₀ were much lower in CYP3A5 expressers than in non-expressers on the 3rd day, 7th day, 14th day and 1st month post-transplantation (P < 0·01); however, no significant differences were found on the 3rd and 6th months post-transplantation. All of the dose-adjusted C₀ in CYP3A5 expressers were significantly lower than non-expressers (P < 0·01). Less of the recipients achieving target C₀ (4-8 ng/mL) were found in CYP3A5 expressers than in non-expressers after initial dose (35·7% vs. 50%). Meanwhile, CYP3A5 non-expressers were detected having higher C₀ (>8 ng/mL) during 3 months post-transplantation. Besides, the proportions in the two groups both increased gradually over time and up to 91·8% and 94% on the 6th month, respectively.

WHAT IS NEW AND CONCLUSION

There are no significant differences in serum creatinine, haematocrit and albumin values between CYP3A5 expressers and non-expressers. CYP3A5 expressers have decreased dose-adjusted tacrolimus C₀ when compared to non-expressers. Dose-adjusted C₀ of tacrolimus increases in a time-dependent manner in both groups.

[Salvage surgical treatment for local recurrent nasopharyngeal cancer]

The salvage radiation or surgery is the main choice for recurrent nasopharyngeal cancer now. However the recurrent tumor becomes radiation insensitive and meanwhile,morbidity and mortality become higher.Recently the endoscopic salvage surgery has been developed;the collective evidence from a number of such studies suggests that endoscopic nasopharyngectomy is a safe and effective procedure for the treatment of rNPC.This article reviewed related researches about the feasibility,methods, and current situation of endoscopic salvage surgery.

Extracellular DNA traps released by acute promyelocytic leukemia cells through autophagy

Acute promyelocytic leukemia (APL) cells exhibit disrupted regulation of cell death and differentiation, and therefore the fate of these leukemic cells is unclear. Here, we provide the first evidence that a small percentage of APL cells undergo a novel cell death pathway by releasing extracellular DNA traps (ETs) in untreated patients. Both APL and NB4 cells stimulated with APL serum had nuclear budding of vesicles filled with chromatin that leaked to the extracellular space when nuclear and cell membranes ruptured. Using immunofluorescence, we found that NB4 cells undergoing ETosis extruded lattice-like structures with a DNA-histone backbone. During all-trans retinoic acid (ATRA)-induced cell differentiation, a subset of NB4 cells underwent ETosis at days 1 and 3 of treatment. The levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were significantly elevated at 3 days, and combined treatment with TNF-α and IL-6 stimulated NB4 cells to release ETs. Furthermore, inhibition of autophagy by pharmacological inhibitors or by small interfering RNA against Atg7 attenuated LC3 autophagy formation and significantly decreased ET generation. Our results identify a previously unrecognized mechanism for death in promyelocytes and suggest that ATRA may accelerate ET release through increased cytokines and autophagosome formation. Targeting this cellular death pathway in addition to conventional chemotherapy may provide new therapeutic modalities for APL.

The efficacy and safety of intensified enteric-coated mycophenolate sodium with low exposure of calcineurin inhibitors in Chinese de novo kidney transplant recipients: a prospective study

AIMS

The aim of this study was to investigate the efficacy and safety of a transient intensified enteric-coated mycophenolate sodium (EC-MPS) dosing regimen with low exposure of calcineurin inhibitors (CNIs) in Chinese de novo kidney transplantation.

METHODS

In a 6-month prospective study, a total of 97 recipients were enrolled and assigned to either an intensified EC-MPS dosing (IS) regimen or a standard EC-MPS dosing (SD) regimen. The area under the curve (AUC) of MPA was assessed at week 1 post transplant. The incidences of acute rejection, patient and graft survival, renal allograft function and adverse events were analysed.

RESULTS

The IS regimen displayed a trend of acute rejection risk reduction (IS 2.7% vs. SD 13.3%, p = 0.061) and allograft function improvement (IS 62.8 ± 14.0 ml/min per 1.73 m(2) vs. SD 56.6 ± 18.3 ml/min per 1.73 m(2) , p = 0.084) after 6-month follow-up. MPA-AUC0-12 h was substantially higher in the intensified EC-MPS group than the standard EC-MPS group, though without a significant difference (71.4 ± 41.7 vs. 53.0 ± 27.0 mg·h/l, p = 0.107). The IS regimen did not increase the incidence of adverse effects (IS 54.1% vs. 45.0%, p = 0.39), including diarrhoea or leucopenia.

CONCLUSIONS

The intensified EC-MPS dosing regimen maintaining low-dose CNIs in this study may be beneficial for Chinese adult de novo kidney transplant recipients in terms of acute rejection and allograft function and is safe within 6 months post transplant.

High Expression of the Newly Found Long Noncoding RNA Z38 Promotes Cell Proliferation and Oncogenic Activity in Breast Cancer

The aberrant expression of long noncoding RNAs (lncRNAs) has great impacts on cancer origination and progression. In the current study, a newly found lncRNA Z38, which was identified through combining experiments of suppression subtractive hybridization (SSH) and reverse dot-blotting, was found to have high expression in breast cancer. More importantly, inhibiting Z38 expression by gene silencing greatly suppressed breast cancer cell proliferation and tumorigenesis, and treatment with Z38 siRNAs significantly induced cell apoptosis and inhibited tumor growth. In conclusion, the newly found lncRNA Z38, which plays important roles in breast cancer, may act as a candidate biomarker and therapeutic target in carcinomas.

Risk factors for BK virus infection and BK virus-associated nephropathy under the impact of intensive monitoring and pre-emptive immunosuppression reduction

BACKGROUND

BK virus (BKV) nephropathy (BKVN) is an increasingly recognized cause of kidney allograft loss and is thought to be related to the newer, more potent immunosuppressive agents. However, the risk factors for different types of BKV infection under the impact of intensive monitoring and reduction of maintenance immunosuppression are not well understood.

METHODS

Quantitative BKV DNA surveillance in plasma/urine and cytological testing in urine were performed regularly within the first year post-transplantation in 229 kidney recipients. Patients with BK viremia and BKVAN treated with immunosuppression reduction were monitored for BKV every 3-6 months. All the patients were followed up for a minimum of 5 years to exclude later development of BKVAN. Potential variables were compared and analyzed using logistic regression model multivariate analysis to assess and rank the BKV infection-related factors.

RESULTS

Seventy-eight (34.1%) patients had decoy cells, 99 (43.2%) BK viruria, 38 (16.6%) BK viremia, and 7 (3.1%) BKVAN. Risk for decoy cells, BK viruria, and viremia, and BKVAN in univariate analyses were higher with tacrolimus (Tac) and deceased kidney donation. Multivariate analysis showed that Tac ([HR, 2.7; P = .008], [HR, 2.3; P = .016], [HR, 2.9; P = .032]) and deceased kidney donation ([HR, 2.5; P = .004], [HR, 2.6; P = .002], [HR, 2.1; P = .071]) were risk factors for BK decoy cells, BK viruria, and viremia, respectively. BKVAN was inclined to the patients with the combination of Tac and mycophenolate mofetil and longer BKV clearance time.

CONCLUSIONS

Tac and deceased kidney donation are independent risk factors for BKV infection under the impact of therapeutic drug monitoring.

Ontogenesis of the collapsed layer during haustorium development in the root hemi-parasite Santalum album Linn

The structure and development of collapsed layers of the haustorium were studied in Santalum album Linn. Through light and transmission electron microscopy, it was shown that the collapsed layers originated from starch-containing cells when the haustorium developed an internal gland, thickened gradually and ultimately developed into the mantle, which, combined with the sucker, buckled the host root. We report on the presence of inter-collapsed layers for the first time. These layers develop after penetration into the host and are located between the intrusive tissues and the vascular meristematic region, gradually linking the collapsed layers and remains around the sucker. The proliferation of cells in the meristematic region and the 'host tropism' of cortical layers contribute to pressure within the haustorium and result in development of the collapsed layers. Besides, starch-containing cells that turn into collapsed layers are vulnerable to pressure as they lack a large vacuole, have uneven cell wall thickness and a loose cell arrangement. We proposed that the functions of collapsed layers are to efficiently assure that cell inclusion and energy concentrate at the inner meristematic region and are recycled to affect penetration, reinforce the physical connection between the sandalwood haustorium and host root, and supply space for haustorial development.

Anti-TCRβ mAb induces long-term allograft survival by reducing antigen-reactive T cells and sparing regulatory T cells

TCR specific antibodies may modulate the TCR engagement with antigen-MHC complexes, and in turn regulate in vivo T cell responses to alloantigens. Herein, we found that in vivo administration of mAbs specific for mouse TCRβ (H57-597), TCRα or CD3 promptly reduced the number of CD4(+) and CD8(+) T cells in normal mice, but H57-597 mAb most potently increased the frequency of CD4(+) Foxp3(+) Treg cells. When mice were injected with staphylococcal enterotoxin B (SEB) superantigen and H57-597 mAb, the expansion of SEB-reactive Vβ8(+) T cells was completely abrogated while SEB-nonreactive Vβ2(+) T cells remained unaffected. More importantly, transient H57-597 mAb treatment exerted long-lasting effect in preventing T cell responses to alloantigens, and produced long-term cardiac allograft survival (>100 days) in 10 out of 11 recipients. While Treg cells were involved in maintaining donor-specific long-term graft survival, T cell homeostasis recovered over time and immunity was retained against third party allografts. Moreover, transient H57-597 mAb treatment significantly prolonged survival of skin allografts in naïve recipients as well as heart allografts in skin-sensitized recipients. Thus, transient modulation of the TCRβ chain by H57-597 mAb exhibits potent, long-lasting therapeutic effects to control alloimmune responses.

Horizontal gene transfer in herpesviruses identified by using support vector machine

Horizontal gene transfer (HGT) is the probable origin of new genes. Identification of HGT-introduced genes would be helpful to the understanding of the genome evolution and the function prediction of new genes. In this study, a method using support vector machine (SVM) was used to distinguish horizontally transferred genes and non-horizontally transferred genes of mammalian herpesviruses based on the atypical composition identification, with accuracy higher than 95% within a reasonable length of time by using just a common PC. This identified 302 putative horizontally transferred genes, 171 genes being identified for the first time. Although most putative transferred genes are of unknown function, many genes have been discovered or predicted to encode glycoproteins or membrane proteins.

Development of rapid immunoassays for the detection of ractopamine in swine urine

The monoclonal antibodies (mAbs) against ractopamine (Rac) were prepared and their properties identified by indirect competitive enzyme-linked immunoabsorbant assay (ELISA). The IC(50) of mAbs was 2.7 ng ml(-1) towards Rac or 9.3 ng ml(-1) towards Rac-glucuronides and no cross-reactivity (CR) towards other competitors except dobutamine (CR: 3.76%). Based on the mAbs, the Rac-kit (kit) and Rac-strip (strip) were developed to detect Rac residues in swine urine. The strip and kit assay could be performed within 5-10 min and 2 h, respectively, allowing the analysis of urine samples without the need for sample clean-up. The detection limits were 1 ng ml(-1) for kit and 3 ng ml(-1) with the unaided eye, and 0.2 ng ml(-1) with the Strip Reader for strip. The correlation coefficients (R(2)) were 0.988 for kit in the range 0-128.0 ng ml(-1), and 0.987 for strip in the range 0-10.8 ng ml(-1). Comparing the gas chromatography-mass spectrometry (GC-MS) with the kit or strip in swine urine spiked with Rac standards, the differences ranged from 1.4% to 4.5% for kit and 1.0% to 4.7% for strip. However, the differences were greater than 54% for the kit and 55% for the strip test for the analysis of urine from swine treated with Rac. The results obtained from GC-MS using hydrolysed urine samples were generally in good agreement with those obtained from strip or kit using non-hydrolysed urine samples.

Distinctly different expression of cytokines and chemokines in the lungs of two H5N1 avian influenza patients

The pathogenesis of human H5N1 influenza remains poorly understood and controversial. 'Cytokine storm' has been hypothesized to be the main cause of the severity of this disease. However, the significance of this hypothesis has been called into question by a recent report, which demonstrates that inhibition of the cytokine response did not protect against lethal H5N1 influenza infection in mice. Here we showed discrepant findings in two adult H5N1 autopsies and a fetus obtained at autopsy which also raise doubt about this hypothesis. Antigens of 10 cytokines/chemokines which were found to be significantly elevated in previous H5N1-infected patients and in vitro experiments, and mRNA of eight of these, were absent from the lungs of a pregnant woman and her fetus. In contrast, antigens of seven cytokines/chemokines and mRNA of six of these were found to be increased in the lungs of a male autopsy. The cells expressing these cytokines and chemokines were identified as type II pneumocytes, bronchial epithelial cells, macrophages and vascular endothelial cells. Levels of cytokines and chemokines in the serum of the male case were also significantly higher than those of infectious (infection other than by H5N1) and non-infectious controls. In comparison with results from our previous study, it appeared that the male case had increased cytokine/chemokine expression but reduced viral load, while the pregnant female had diminished cytokine/chemokine expression but a significantly increased viral load in the lungs. These disparate findings in these two cases suggest that 'cytokine storm' alone could not be a sufficient explanation for the severe lung injury of this newly emerging disease.

Whole-genome phylogenetic analysis of herpesviruses

A comprehensive phylogenetic analysis of 45 herpesviruses was performed based on whole-genome sequences. We used 4 methods, namely the alignment of conserved gene sequences (excluding 5 herpesviruses), compositional vector tree (CVTree) method, local homology analysis, and gene content analysis. The obtained results showed good consistency between the phylogenetic trees prepared by these methods and likewise, the obtained classification of the herpesviruses was consistent with their current taxonomic designation. The herpesviruses with the ambiguous classification or not assigned in the family or with the newly published genomes were also phylogenetically classified.

Maternal mortality in Yunnan, China: recent trends and associated factors

OBJECTIVE

Yunnan Province, located in southwest China, is one of the poorest province in China. The maternal mortality ratio (MMR) is about twice the national average (56.2/100,000 live births), and in remote mountainous regions, the rate is five times higher. This study aimed to examine the progress in reduction of maternal mortality in the 1990s and early 2000s and the factors associated with this reduction in Yunnan.

DESIGN

A population-based, longitudinal, ecological correlation study.

SETTING

A remote province of China with a proportionately large indigenous population.

POPULATION

Populations at county, prefecture and provincial level.

METHODS

Using maternal mortality data collected at the province, prefecture/region and county levels, trend and time series analyses and multivariate linear regression analyses were performed using SPSS (Version 13).

MAIN OUTCOME MEASURE

MMR and its change over time.

RESULTS

MMR declined substantially in the 1990s at a rate of 3.0% per year. Utilisation of prenatal and obstetric care increased and was significantly correlated with the declining trend in MMR. Hospital delivery was a strong predictor of MMR, independent of social and economic development. Both low income and illiteracy were significantly associated with increased MMR.

CONCLUSIONS

Declines in maternal mortality in Yunnan over the past 14 years appear to reflect health, social and economic interventions implemented in the 1990s. The association of hospital delivery with maternal mortality may be due to the effective management of severe pregnancy and birth complications. Low income and illiteracy were associated with MMR but primarily through their impact on the use of prenatal and obstetric care.

Acetylcholinesterase expression mediated by c-Jun-NH2-terminal kinase pathway during anticancer drug-induced apoptosis

It has been shown that acetylcholinesterase (AChE) expression was induced during apoptosis and the anti-sense oligonucleotides and siRNA of AChE may prevent apoptosis in various cell types. However, the mechanisms underlying AChE upregulation remain elusive. We demonstrated here that c-Jun NH2-terminal kinase (JNK) could mediate AChE expression. In this study, both etoposide and excisanin A, two anticancer agents, induced apoptosis in colon cancer cell line SW620 as determined by Annexin V staining, the cleavage of caspase-3 and the proteolytic degradation of poly (ADP-ribose) polymerase (PARP). The results showed that both the agents upregulated AChE in SW620 cells. In the meantime, JNK was also activated and the expression and phosphorylation of c-Jun increased in SW620 cells exposed to the two agents. The induced AChE mRNA and protein expression could be blocked by SP600125, a specific inhibitor of SAPK/JNK, and small interfering RNA directed against JNK1/2. Transfection with adenovirus-mediated dominant negative c-Jun also blocked the upregulation of AChE expression. Together, these results suggest that AChE expression may be mediated by the activation of JNK pathway during apoptosis through a c-Jun-dependent mechanism.

Senescence and telomere shortening induced by novel potent G-quadruplex interactive agents, quindoline derivatives, in human cancer cell lines

Agents stabilizing G-quadruplexes have the potential to interfere with telomere replication by blocking the elongation step catalysed by telomerase or telomerase-independent mechanism and could therefore act as antitumor agents. In this study, we found that quindoline derivatives interacted preferentially with intramolecular G-quadruplex structures and were novel potent telomerase inhibitors. Treatment with quindoline derivatives reproducibly inhibited telomerase activity in human leukemia K562 cells and colon cancer SW620 cells. N'-(10H-Indolo [3,2-b] quinolin-11-yl)-N, N-dimethyl-propane-1,3-diamine (SYUIQ-5), (one of quindoline derivatives), when added to K562 and SW620 cell culture at nonacute cytotoxic concentrations, increased time of population doublings of K562 and SW620 cells, induced a marked cessation in cell growth and cellular senescence phenotype after 35 and 18 days, respectively. Growth cessation was accompanied by a shortening of telomere length, and induction of p16, p21 and p27 protein expression. However, another compound SYUIQ-7 with greater IC(50) for telomerase had no obvious cellular effect in nonacute cytotoxic concentrations. These results indicate that quindoline derivatives as novel potent G-quadruplex interactive agents induce senescence and telomere shortening in cancer cells and therefore are promising agents for cancer treatment.

The expression of antiapoptotic protein survivin is transcriptionally upregulated by DEC1 primarily through multiple sp1 binding sites in the proximal promoter

Human differentially expressed in chondrocytes (DEC), mouse stimulated with retinoic acid and rat split and hairy related proteins constitute a structurally distinct class of the basic helix-loop-helix proteins. DEC1 is abundantly expressed in tumors and protects against apoptosis induced by serum starvation. In this study, we report that DEC1 antiapoptosis is achieved by inducing survivin, an antiapoptotic protein. In paired tumor-normal tissues, survivin and DEC1 exhibited a paralleled expression pattern. Tetracycline-induced expression of DEC1 in stable lines proportionally increased the expression of survivin. In reporter assays, DEC1 transactivated the survivin promoter but repressed the DEC2 promoter. In contrast to the repression, the activation was delayed and varied depending on serum concentrations and cycle blockers. Studies with reporter mutants located, in the survivin promoter, two Sp1 sites that supported DEC1 transactivation. Electrophoretic mobility shift assay and chromatin immunoprecipitation detected the presence of DEC1 in the survivin promoter. These findings establish that the survivin gene is a transcription target of DEC1, and induction of survivin is at least in part responsible for DEC1 antiapoptosis.