Re-expression of ARHI (DIRAS3) induces autophagy in breast cancer cells and enhances the inhibitory effect of paclitaxel.

BACKGROUND: ARHI is a Ras-related imprinted gene that inhibits cancer cell growth and motility. ARHI is downregulated in the majority of breast cancers, and loss of its expression is associated with its progression from ductal carcinoma in situ (DCIS) to invasive disease. In ovarian cancer, re-expression of ARHI induces autophagy and leads to autophagic death in cell culture; however, ARHI re-expression enables ovarian cancer cells to remain dormant when they are grown in mice as xenografts. The purpose of this study is to examine whether ARHI induces autophagy in breast cancer cells and to evaluate the effects of ARHI gene re-expression in combination with paclitaxel. METHODS: Re-expression of ARHI was achieved by transfection, by treatment with trichostatin A (TSA) or by a combination of TSA and 5-aza-2'-deoxycytidine (DAC) in breast cancer cell cultures and by liposomal delivery of ARHI in breast tumor xenografts. RESULTS: ARHI re-expression induces autophagy in breast cancer cells, and ARHI is essential for the induction of autophagy. When ARHI was re-expressed in breast cancer cells treated with paclitaxel, the growth inhibitory effect of paclitaxel was enhanced in both the cell culture and the xenografts. Although paclitaxel alone did not induce autophagy in breast cancer cells, it enhanced ARHI-induced autophagy. Conversely, ARHI re-expression promoted paclitaxel-induced apoptosis and G2/M cell cycle arrest. CONCLUSIONS: ARHI re-expression induces autophagic cell death in breast cancer cells and enhances the inhibitory effects of paclitaxel by promoting autophagy, apoptosis, and G2/M cell cycle arrest.

Isolation and Identification of a Murine Norovirus Persistent Infection Strain in China.

Murine Norovirus (MNV) is one of the most known viruses among viruses in mice. Because of the high prevalence of MNV in frequently used laboratory animals in biomedical researches, there is a significant impact of MNV. There may be different prevalence degrees and molecular characteristics of MNV in different regions around the world. Here, we reported an MNV strain "designated HBTS-1806" isolation from commercial mice's feces that caused a detectable cytopathic effect (CPE) in RAW264.7 cells. According to electron microscopy, the virus was 50-70 nm in diameter. The complete genome of HBTS-1806 is 7383 nucleotides with a structure similar to that of MNV reference strains. According to phylogenetic analysis on the basis of the whole genome, HBTS-1806 shared nucleotide sequence identities of 90.2-95.4% with other Chinese isolates reported. Analysis of amino acid sequence on the basis of ORF1 and ORF2 suggested that the isolated strain may be derived from recombination. Although no gross lesions or histopathological changes were found from mice infected with 5 × 105 TCLD50 of MNV by oral gavage inoculation, the intestinal virus loads lasted 12 weeks, suggesting a persistent infection strain of MNV isolate in China.

Application of kushenin on patients with chronic hepatitis C after renal transplantation.

OBJECTIVE: To evaluate the efficacy of kushenin in treating patients with chronic hepatitis C after renal transplantation. METHODS: Fifty-five patients were randomly assigned by lottery to the treatment group (29 cases) and control group (26 cases). The same immunosuppression therapy was given to all patients in both groups. Patients in the treatment group were treated with kushenin 0.6 g once a day, while those in the control group were treated with conventional liver protective agents such as vitamins. The treatment duration of both groups was 3 months. The incidences of serious hepatitis and acute rejection reaction, serum biochemistry parameters including indicators of liver and kidney functions, hepatic fibrosis index, and serum HCV-RNA were compared between the two groups. RESULTS: (1) The incidence of serious hepatitis in the treatment group and the control group was 3.45% (1/29 cases) and 11.54% (3/26 cases), respectively, which was insignificantly different between the two groups (P=0.335). (2) The incidence of acute rejection in the treatment group was 6.90% (2/29 cases) and that in the control group was 7.69% (2/26 cases), showing insignificant difference (P=0.335). (3) The differences in serum alanine aminotransferase (ALT), direct bilirubin (DBIL), hyaluronic acid (HA), propeptide collagen type III (PC III), laminin (LN), collagen type IV (Col IV) levels between the two groups were insignificant before transplantation (P>0.05), while the above-mentioned parameters in the treatment group were significantly lower than those in the control group after transplantation (P<0.05). The difference in serum creatinine (SCr) and endogenous creatinine clearance rate (CCr) between the two groups was insignificant before and after transplantation (P>0.05). (4) The negative conversion rate of HCV-RNA in the treatment group was 31.03% (9/29 cases), significantly higher than the value of 11.54% (3/26 cases) in the control group after transplantation (P<0.05). (5) The levels of serum ALT and DBIL in patients with HCV-RNA converted to negative were significantly lower than those with still-positive HCV-RNA (P<0.05). CONCLUSIONS: Kushenin has a certain effect on inhibiting the proliferation of HCV, protecting liver cells, and anti-liver fibrosis. On the other hand, it has no obvious influence on renal allograft function. Thus, the drug is clinically safe and effective for use in treating patients with chronic hepatitis C after renal transplantation.

Inhibition of pre-B cell colony-enhancing factor attenuates inflammation induced by hyperoxia in EA.hy926 cells.

The aim of this study was to investigate the role of pre-B cell colony-enhancing factor (PBEF) in the pathogenesis of bronchopulmonary dysplasia (BPD) using an established cell model of BPD. For this purpose, EA.hy926 cell cultures were divided into 4 groups as follows: the air group as the blank control, the hyperoxia group, the hyperoxia plus PBEF siRNA group and the hyperoxia plus scramble siRNA group. Cell viability and the generation of reactive oxygen species (ROS) were determined using respective kits. Moreover, the protein and mRNA expression levels of PBEF, interleukin-8 (IL-8) and tumor necrosis factor-α (TNF-α) were also detected by corresponding methods. Compared with the hyperoxia group, the ROS levels in the hyperoxia plus PBEF siRNA group were significantly reduced (P<0.01). The silencing of PBEF increased cell viability compared with the hyperoxia group. The protein and mRNA expression levels of PBEF, IL-8 and TNF-α were all decreased in the hyperoxia plus PBEF siRNA group compared with the hyperoxia group (P<0.01). Our study thus demonstrates that the inhibition of PBEF attenuates oxidative stress and inflammation induced by hyperoxia in EA.hy926 cells, suggesting that PBEF may be a potential diagnostic and therapeutic target, which may be used for the development of novel treatment strategies for BPD.

A practical community-based response strategy to interrupt Ebola transmission in sierra Leone, 2014-2015.

BACKGROUND: The Ebola virus disease spread rapidly in West Africa in 2014, leading to the loss of thousands of lives. Community engagement was one of the key strategies to interrupt Ebola transmission, and practical community level measures needed to be explored in the field and tailored to the specific context of communities. METHODS: First, community-level education on Ebola virus disease (EVD) prevention was launched for the community's social mobilizers in six districts in Sierra Leone beginning in November 2014. Then, from January to May of 2015, in three pilot communities, local trained community members were organized to engage in implementation of EVD prevention and transmission interruption measures, by involving them in alert case report, contact tracing, and social mobilization. The epidemiological indicators of transmission interruption in three study communities were evaluated. RESULTS: A total of 6 016 community social mobilizers from 185 wards were trained by holding 279 workshops in the six districts, and EVD message reached an estimated 631 680 residents. In three pilot communities, 72 EVD alert cases were reported, with 70.8 % of them detected by trained local community members, and 14 EVD cases were finally identified. Contact tracing detected 64.3 % of EVD cases. The median duration of community infectivity for the cases was 1 day. The secondary attack rate was 4.2 %, and no third generation of infection was triggered. No health worker was infected, and no unsafe burial and noncompliance to EVD control measures were recorded. The community-based measures were modeled to reduce 77 EVD cases, and the EVD-free goal was achieved four months earlier in study communities than whole country of Sierra Leone. CONCLUSIONS: The community-based strategy of social mobilization and community engagement was effective in case detection and reducing the extent of Ebola transmission in a country with weak health system. The successfully practical experience to reduce the risk of Ebola transmission in the community with poor resources would potentially be helpful for the global community to fight against the EVD and the other diseases in the future.

Potential risk factors for the development of seroma following mastectomy with axillary dissection.

Seroma is a common complication following breast cancer surgery and the controllable predictive factors remain unknown. Patients who underwent mastectomy with axillary dissection between 2008 and 2011 in our hospital were retrospectively investigated. The demographics, clinical characteristics and therapeutic factors of each patient were recorded. The association of seroma incidence with each variable was evaluated by univariate logistic regression analysis. All the variables were considered independent predictors of seroma incidence. The probability of developing seroma following surgery was evaluated by multivariate logistic regression analysis. A total of 102 patients, with a mean age of 54.86±13.02 years (range, 30-89 years), were included in this study and the incidence of seroma was found to be 22.55%. The operative time (P=0.0066, coefficient = 0.0261, OR=1.03) and the use of patient-controlled intravenous analgesia (PCA) (P=0.0002, coefficient = -1.8089, OR=0.03, ref = no) was significantly associated with the incidence of seroma postoperatively. In conclusion, the prediction of the development of seroma following mastectomy with axillary dissection is challenging. However, a longer operative time and the non-use of PCA may represent potential risk factors for this complication.

Expression and clinical significance of osteopontin in calcified breast tissue.

Osteopontin (OPN) is an integrin-binding protein, believed to be involved in a variety of physiological cellular functions. The physiology of OPN is best documented in the bone where this secreted adhesive glycoprotein appears to be involved in osteoblast differentiation and bone formation. In our study, we used semi-quantitative RT-PCR of osteopontin in calcification tissue of breast to detect breast cancer metastasis. The obtained data indicate that the expression of osteopontin is related to calcification tissue of breast, and possibly with the incidence of breast cancer. The expression strength of OPN by RT-PCR detection was related to the degree of malignancy of breast lesions, suggesting a close relationship between OPN and breast calcification tissue. The results revealed that expression of OPN mRNA is related to calcification of breast cancer tissue and to the development of breast cancer. Determination of OPN mRNA expression can be expected to be a guide to clinical therapy and prediction of the prognosis of breast cancer patients.

Effect of lentivirus-mediated shRNA targeting VEGFR-3 on proliferation, apoptosis and invasion of gastric cancer cells.

It has been reported that vascular endothelial growth factor receptor 3 (VEGFR-3) is highly expressed in most tumor tissues, including gastric cancer. However, the effects of VEGFR-3 knockdown on the proliferation, apoptosis and invasion of gastric cancer cells and downstream signaling molecules have not yet been well established. In the present study, four short hairpin RNA (shRNA) sequences targeting the VEGFR-3 gene (NM_002020) were designed and cloned into a lentiviral vector, pRNAT-U6.2/Lenti, to construct four recombinant lentiviral vectors. The vectors with the two highest interfering efficiencies were selected to be co-transfected with packaging vectors in HEK293T cells to assemble lentivirus particles. Results from Western blot analysis showed that the VEGFR-3 shRNA-4 lentivirus-infected group (sh#4) had the highest efficiency of gene silencing in the MKN45 cell line compared with the parental and control group. The sh#4 group significantly slowed cell proliferation, decreased the mean percentage of S-phase cells and increased the mean percentage of G1 phase cells, promoted cell apoptosis, and also significantly inhibited cell invasion of MKN45 compared with the other two groups. Furthermore, the expression of the anti-apoptotic factor Bcl-2 was significantly decreased in the sh#4 group compared to that of the other two groups. Moreover, results from qRT-PCR revealed that knockdown of VEGFR-3 with the shRNA lentiviral vector resulted in down-regulation of the downstream neural cell adhesion molecule contactin-1 (CNTN-1). In conclusion, the recombinant lentivirus particles were able to remarkably suppress VEGFR-3 expression, regulate the cell cycle, inhibit proliferation and induce apoptosis in the MKN45 cell lines.

[Impacts on nutrient export by landscape heterogeneity based on sub-watershed].

Landscape features of a watershed are important factors affecting non-point source (NPS) pollution. Sub-watershed bounds were delineated and landscape heterogeneity was analyzed based on GIS and RS in Xitiaoxi watershed which located the upper reach of Taihu Lake area. Nutrient export intensity of sub-watersheds was estimated by revised export coefficient model. Then the relationships between nutrient export and main landscape types, as well as Shannon diversity index (SHDI) in sub-watershed units were analyzed. Results show, TN and TP export intensity have obvious spatial difference, which changed from 3.01 kg/(hm2 x a) to 15.44 kg/(hm2 x a) and 0.049 kg/(hm2 x a) to 0.355 kg/(hm2 x a) respectively. The dominated landscape types including cultivated land and forest land quantitatively related with nutrient export intensity. TN and TP export intensity will decrease 0.203 1 kg/(hm2 x a) and 0.0152 kg/(hm2 x a) respectively with 10% increased of forest area, and will increase 0.5726 kg/(hm2 x a) and 0.0273 kg/(hm2 x a) with 10% increased of cultivated land area. The relationship between nutrient export intensity and SHDI exhibited second-degree polynomial, export intensity increased by SHDI increasing and to maximum when SHDI equals 1.5, then decreased with SHDI increasing. This research results will provide an important reference value for NPS management.

[Comparison of different isolation methods on adult Sertoli cells co-transplanted with islets].

AIM: To establish a more convenient and effective method for isolating adult Sertoli cells and apply the method to islet transplantation. METHODS: Trypsin, DNase, collagenase and hyaluronidase were used for a one-step digestion in group A. A two-step digestion was used in group B, in which testis tissues were first digested by trypsin and DNase and then were digested by collagenase and hyaluronidase. In group C, trypsin and DNase were used in the first step of digestion, hyaluronidase was used in the second step and collagenase was used in the third step. Sertoli cells were identified by morphology and immunohistochemistry and the viability and purity of Sertoli cells were detected by MTT and flow cytometry (FCM). Expression of Fas-L was detected by Western blot and the effects of the co-transplantation of islets and Sertoli cells were compared between the three groups. RESULTS: Typical Sertoli cells were seen after isolation using the three different methods. Sertoli cells isolated by method A and method B were large in number while those isolated by method B and method C were pure. The results of MTT showed that the viability of Sertoli cells in group B was significantly higher than that in group A and group C (P<0.05) and Western blot results showed that expression of Fas-L on Sertoli cells in group B was significantly stronger than that in group A and group C (P<0.05). The purity of Sertoli cells detected by FCM in group B and group C were significantly higher than that in group A (P<0.05). The survival of islets co-transplanted with Sertoli cells to renal capsule of diabetic mice was significantly longer in group B compared with that in control group as well as in group A and group C (P<0.05). CONCLUSION: Sertoli cells obtained by the two-step digestion method are of higher purity and viability, which significantly prolong the survival of islet graft by co-transplantation.

Study on systemic immune tolerance induction in rat islet transplantation by intravenous infusion of Sertoli cells.

BACKGROUND: Sertoli cells are usually co-transplanted with pancreatic islets to induce local immune tolerance. In this report, we used infusion with Sertoli cells in islet transplantation to induce systemic immune tolerance and studied the mechanism of the tolerance induction. METHODS: Streptozotocin-induced diabetic rats were divided into four groups before islet transplantation: group A as control; group B with intravenous infusion of Sertoli cells; group C with Sertoli cell infusion and Fas ligand antibody treatment; and group D with Sertoli cell infusion and transforming growth factor-beta1 antibody treatment. The mean survival time (MST) and insulin expression of islet grafts were measured. The number of lymphocytes and the levels of cytokines in peripheral blood were also measured. RESULTS: Group B had the longest MST of islet allografts (41.6+/-4.20 days) followed by groups C, D, and A (P<0.05). Immunohistochemistry showed similar results with MST. The rats in group B had the least CD4 T cells (only 15.6%+/-6.4%) compared with other groups (P<0.05). The numbers of CD8 T cells in rats of groups B (11.2%+/-4.3%) and D (14.5%+/-5.6%) were significantly lower than those of groups A and C (P<0.05). After transplantation, group B's interleukin (IL)-2 level (1.92+/-0.68 ng/mL) was found to be significantly lower than that of other groups (P<0.05). Interferon-gamma showed similar pattern of change as IL-2 (P<0.05). Groups A and D had significantly lower levels of IL-4 (4.31+/-1.97 pg/mL 4.69+/-1.33 pg/mL, respectively) than groups B and C (P<0.05). CONCLUSION: Infusion of Sertoli cells could effectively prolong the survival of islet grafts and reduce peripheral blood lymphocyte and cytokine levels. In this process, transforming growth factor-beta1 played a major role and Fas ligand played a smaller additional role.

High incidence of JC viruria in JC-seropositive older individuals.

The prevalence of the human JC virus (JCV) in the general population at various ages was investigated. Polymerase chain reaction was employed to detect viral DNA in the urine. The results showed that the incidence of JC viruria was low in the young population, but it was high in the elderly. Hemagglutination inhibition assay was performed for JCV seroprevalence study. The results showed that the seropositive rate of JCV was lower in children than that in adults. The ratio of viruria to seropositive for JCV increased with age and reached 79.7% for those older than 70 years. The results indicated that aging immunity may correlate with JCV reactivation.