Noninvasive evaluation of HABP1 expression with 99mTc-labeled small-interference RNA in ovarian cancer.

PURPOSE: Ovarian cancer is one of the most common gynecological cancers in women with a low 5-year survival rate. Evaluation of hyaluronic acid-binding protein 1 (HABP1) level can provide important information for the diagnosis and treatment of ovarian cancer. In this study, we designed a novel HABP1 probe based on 99mTc-radiolabeled small-interference RNA (siRNA) for detecting HABP1 expression noninvasively in vivo, thereby providing a new method for its diagnosis and treatment. METHODS: A specific siHABP1 was selected because of its targetability and silencing effect. A negative control siRNA (NCsiRNA) with no homology with the human genome was used. SiHABP1 and NCsiRNA were radiolabeled with 99mTc using the bifunctional chelating agent hydrazinonicotinamide (HYNIC). The radiochemical purity and in vitro stability of the probe were determined by HPLC. The binding activity was measured by western blotting (WB) and RT-PCR. The HABP1-overexpressing human ovarian cancer cell line HO-8910 was used for cell uptake experiments, which were performed with or without transfection and measured with a gamma counter. HO8910-bearing mice were imaged at 1, 4, and 10 h, and biodistribution analysis was performed at 1, 4, 6, and 10 h after injection of 99mTc-HYNIC-siRNA. RESULTS: 99mTc-HYNIC-siHABP1 had high radiochemical purity and good in vitro stability, and showed the same binding capacity and silencing effect as siHABP1. SPECT imaging showed that tumors were clearly visualized at 10 h after injection of 99mTc-HYNIC-siHABP1 but not after 99mTc-HYNIC-NCsiRNA, implying specific binding. The biodistribution results were consistent with those of SPECT imaging. CONCLUSIONS: We showed that 99mTc-HYNIC-siHABP1 is a feasible probe for the noninvasive visualization of HABP1 expression in ovarian cancer.

Automatic analysis of integrated magnetic resonance and positron emission tomography images improves the accuracy of detection of focal cortical dysplasia type IIb lesions.

We aimed to develop an efficient and objective pre-evaluation method to identify the precise location of a focal cortical dysplasia lesion before surgical resection to reduce medication use and decrease the post-operative frequency of seizure attacks. We developed a novel machine learning-based approach using cortical surface-based features by integrating MRI and metabolic PET to identify focal cortical dysplasia lesions. Significant surface-based features of 22 patients with histopathologically proven FCD IIb lesions were extracted from PET and MRI images using FreeSurfer. We modified significant parameters, trained and tested the XGBoost model using these surface-based features, and made predictions. We detected lesions in all 20 patients using the XGBoost model, with an accuracy of 91%. We used one-way chi-squared test to test the null hypothesis that the population proportion was 50% (p = 0.0001), indicating that our classification of the algorithm was statistically significant. The sensitivity, specificity, and false-positive rates were 93%, 91%, and 9%, respectively. We developed an objective, quantitative XGBoost classifier that combined MRI and PET imaging features to locate focal cortical dysplasia. This automated method yielded better outcomes than conventional visual analysis and single modality quantitative analysis for surgical pre-evaluation, especially in subtle or visually unidentifiable FCD lesions. This time-efficient method would also help doctors identify otherwise overlooked details.

Inhibition of expression of BmNPV cg30 by bmo-miRNA-390 is a host response to baculovirus invasion.

Bombyx mori larvae exhibit in vivo defensive reactions immediately after invasion by a virus. One of these defense systems is to express appropriate microRNAs (miRNAs) to respond to the infection. A novel Bombyx mori-encoded miRNA, bmo-miR-390, was identified previously by high-throughput sequencing. Based on bioinformatic predictions, the Bombyx mori nuclear polyhedrosis virus cg30 gene (BmNPV-cg30) is one of the target genes of bmo-miR-390. In this study, expression vectors with an enhanced green fluorescence protein (EGFP) or a luciferase (luc) reporter gene together with bm-miR-390 or the cg30 3' UTR were constructed and used to co-transfect BmN cells. Using a dual luciferase reporter (DLR) assay, we found that bmo-miR-390 significantly downregulates the expression of BmNPV-cg30 (P < 0.05) in vitro. Moreover, artificially synthesized bmo-miR-390 mimics enhanced the regulatory effect of bmo-miR-390, while an inhibitor eliminated the inhibitory effect. These results show for the first time that bmo-miR-390 can effectively downregulate the expression of BmNPV-cg30 in BmNPV-infected BmN cells.

Isolation and characterization of an avian-origin H3N8 canine influenza virus from a dog in eastern China.

Previous studies have shown that dogs are susceptible to influenza A viruses, and the close contact between dogs and humans poses a threat to public health. In 2015, a novel H3N8 influenza virus was isolated from a dog in eastern China. This strain was characterized by whole-genome sequencing with subsequent phylogenetic analysis and genetic comparison and found to be most closely related to avian influenza viruses co-circulating in China. It was able to replicate in mice without prior adaptation. The continued circulation of this novel H3N8 influenza virus in dogs could endanger other mammalian species.

Percentage and function of CD4+CD25+ regulatory T cells in patients with hyperthyroidism.

The current study observed the percentage of peripheral blood (PB) CD4+CD25+ regulatory T cells (Tregs) and the influence of CD4+CD25+ Tregs on the proliferation of naïve CD4 T cells in patients with hyperthyroidism. Furthermore, preliminary discussions are presented on the action mechanism of CD4+CD25+ Tregs on hyperthyroidism attacks. The present study identified that compared with the percentage of PB CD4+CD25+ Tregs in healthy control subjects, no significant changes were observed in the percentage of PB CD4+CD25+ Tregs in patients with hyperthyroidism (P>0.05). For patients with hyperthyroidism, CD4+CD25+ Tregs exhibited significantly reduced inhibition of the proliferation of naïve CD4 T cells and decreased secretion capacity on the cytokines of CD4 T cells, compared with those of healthy control subjects (P<0.05). In addition, it was demonstrated that thyroid function of patients with hyperthyroidism was significantly improved (P<0.05) subsequent to receiving medication. Compared with the percentage of PB CD4+CD25+ Tregs in patients with hyperthyroidism before treatment, no significant changes were observed in the percentage of PB CD4+CD25+ Tregs in hyperthyroidism patients following treatment (P>0.05). In the patients with hyperthyroidism, following treatment, CD4+CD25+ Tregs exhibited significantly increased inhibition of the proliferation of naïve CD4 T cells and increased secretion capacity of CD4 T cell cytokines, compared with those of the patients with hyperthyroidism prior to treatment (P<0.05). PB CD4+CD25+ Tregs function was decreased in patients with hyperthyroidism, and its non­proportional decrease may be closely associated with the occurrence and progression of hyperthyroidism.

Genetic characterization of novel reassortant H5N6-subtype influenza viruses isolated from cats in eastern China.

Cats are susceptible to influenza A viruses and therefore may act as transmission vectors within households, posing a potential public health concern. Two novel reassortant H5N6 influenza viruses were isolated from cats in Zhejiang Province, Eastern China, in 2016. Both viruses were characterized by whole-genome sequencing with subsequent phylogenetic analysis and genetic comparison. Phylogenetic analysis showed that these viruses received their genes from H5N6, H9N2, and H7N9 influenza viruses isolated from China. These H5N6 viruses were able to replicate in mice without prior adaptation. Our results show that continued circulation of these viruses could endanger humans.

BmNPV-miR-415 up-regulates the expression of TOR2 via Bmo-miR-5738.

MicroRNAs (miRNAs) have emerged as key players in host-pathogen interaction and many virus-encoded miRNAs have been identified (computationally and/or experimentally) in a variety of organisms. A novel Bombyx mori nucleopolyhedrosis virus (BmNPV)-encoded miRNA miR-415 was previously identified through high-throughput sequencing. In this study, a BmNPV-miR-415 expression vector was constructed and transfected into BmN cells. The differentially expressed protein target of rapamycin isoform 2 (TOR2) was observed through two-dimensional gel electrophoresis and mass spectrometry. Results showed that TOR2 is not directly a target gene of BmNPV-miR-415, but its expression is up-regulated by BmNPV-miR-415 via Bmo-miR-5738, which could be induced by BmNPV.

Imaging CXCR4 Expression with (99m)Tc-Radiolabeled Small-Interference RNA in Experimental Human Breast Cancer Xenografts.

PURPOSE: Noninvasive quantification of chemokine receptor 4 (CXCR4) expression could serve as a prognostic indicator and may be of value for the design of personalized therapies and posttreatment monitoring. The objective of the present study was to assess the use of (99m)Tc-radiolabeled small-interference RNA (siRNA) targeting CXCR4 to detect CXCR4 expression in vivo. PROCEDURES: CXCR4 siRNAs were radiolabeled with (99m)Tc using the bifunctional chelator hydrazinonicotinamide (HYNIC), and the labeling efficiency, specific activity and radiochemical purity were determined. The stability of the probe in serum was assessed by measuring its radiochemical purity and inhibitory activity by RT-PCR and western blotting. Biodistribution studies and static imaging were performed in MDA-MB-231 tumor-bearing mice. RESULTS: Radiochemical purity remained highly stable in PBS and fresh human serum at room temperature and at 37 °C. Radiolabeled siRNA1 showed strong inhibitory effects similar to those of unlabeled siRNA1 on both CXCR4 messenger RNA (mRNA) and protein in vitro. The excretion of the probe occurred mainly through the liver and kidneys. Tumors were clearly visualized at 1-10 h after injection of the probe, but not after injection of the control probe. CONCLUSIONS: (99m)Tc-labeled CXCR4 siRNA1 shows tumor-specific accumulation and could be a promising strategy for the visualization of CXCR4 expression in human breast cancer.

MDM2 molecular imaging for the prediction of chemotherapeutic sensitivity in human breast cancer xenograft.

The aim of the present study was to investigate the possible use of mouse double-minute 2 (MDM2) molecular imaging to predict chemotherapeutic sensitivity in breast cancer xenografts (BCXs). MCF-7 cells were transfected with MDM2 antisense oligonucleotides (ASONs), and MDM2 expression levels were determined by Western blotting. Cell viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in MCF-7 cells transfected with ASONs and treated with paclitaxel. BCXs were established in nude mice by injection of ASONs, and tumor volumes were measured after paclitaxel treatment. MDM2 ASONs were labeled with 99mTc to generate an MDM2 molecular probe, and MDM2 expression levels were evaluated by imaging and Western blotting. MDM2 ASONs downregulated MDM2 expression in a dose-dependent manner and increased the rate of paclitaxel-induced cell growth inhibition. Imaging of tumors revealed significant differences in the tumor to skeletal muscle (T/M) ratio between groups. Tumor MDM2 protein expression was correlated with T/M ratios at 4 hours (R  =  .880) and 10 hours (R  =  .886). The effect of paclitaxel varied among nude mice bearing BCXs with different concentrations of ASONs, as shown by differences in tumor growth. MDM2 molecular imaging could be a promising method for predicting the sensitivity of BCXs to chemotherapy.