Longitudinal PET studies of mGluR5 in FXS using an FMR1 knockout mouse model.

Fragile X syndrome (FXS) is a monogenic disorder characterized by intellectual disability and behavioral challenges. It is caused by aberrant methylation of the fragile X mental retardation 1 (FMR1) gene. Given the failure of clinical trials in FXS and growing evidence of a role of metabotropic glutamate subtype 5 receptors (mGluR5) in the pathophysiology of the disorder, we investigated mGluR5 function in FMR1 Knockout (FMR1-KO) mice and age- and sex-matched control mice using longitudinal positron emission tomography (PET) imaging to better understand the disorder. The studies were repeated at four time points to examine age- and disease-induced changes in mGluR5 availability using 3-fluoro-[18F]5-(2-pyridinylethynyl)benzonitrile ([18F]FPEB). We found that the binding potential (BP) of [18F]FPEB was significantly lower in the KO mice in mGluR5-implicated brain areas including striatum, cortex, hippocampus, thalamus, and olfactory bulb. The BP also changed with age, regardless of disorder status, increasing in early adulthood in male but not in female mice before decreasing later in both sexes. The difference in mGluR5 availability between the FMR1-KO and control mice and the change in BP in the KO mice as a function of age and sex illustrate the nature of the disorder and its progression, providing mechanistic insights for treatment design.

Life-threatening hemoptysis accompanied by internal thoracic artery aneurysms in a 28-year-old perinatal woman: a case report.

BACKGROUND: Life-threatening hemoptysis presents an immediate diagnostic and therapeutic challenge, especially during the perinatal period. CASE PRESENTATION: A 28-year-old perinatal woman with no significant past medical or surgical history presented with repeating hemoptysis and respiratory failure. Computed tomography revealed a 2.1 × 3.2  cm2 inhomogeneous tumorous lesion in the right superior mediastinum and a right main bronchus obstruction along with atelectasis of the right lung. Bronchoscopy showed a tumorous protrusion blocking the right main bronchus with active hemorrhage, and malignancy was suspected. Bronchial artery embolization (BAE) was performed to control the bleeding. The arteriogram revealed tortuosity, dilation and hypertrophy of the right bronchial arteries and aneurysms of the internal thoracic artery (ITA). The bleeding completely stopped after BAE. Bronchoscopy was performed again to remove residual blood clots. The patient recovered soon after the procedure and was discharged. CONCLUSIONS: Life-threatening hemoptysis concomitant with ITA aneurysms, which may have a misleading clinical diagnosis and treatment options, has not been reported previously in perinatal women. BAE could be used as a first-line treatment irrespective of the underlying causes.

Design, Synthesis, and Characterization of Benzimidazole Derivatives as Positron Emission Tomography Imaging Ligands for Metabotropic Glutamate Receptor 2.

Three benzimidazole derivatives (13-15) have been synthetized as potential positron emission tomography (PET) imaging ligands for mGluR2 in the brain. Of these compounds, 13 exhibits potent binding affinity (IC50 = 7.6 ± 0.9 nM), positive allosteric modulator (PAM) activity (EC50 = 51.2 nM), and excellent selectivity against other mGluR subtypes (>100-fold). [11C]13 was synthesized via O-[11C]methylation of its phenol precursor 25 with [11C]methyl iodide. The achieved radiochemical yield was 20 ± 2% (n = 10, decay-corrected) based on [11C]CO2 with a radiochemical purity of >98% and molar activity of 98 ± 30 GBq/µmol EOS. Ex vivo biodistribution studies revealed reversible accumulation of [11C]13 and hepatobiliary and urinary excretions. PET imaging studies in rats demonstrated that [11C]13 accumulated in the mGluR2-rich brain regions. Pre-administration of mGluR2-selective PAM, 17 reduced the brain uptake of [11C]13, indicating a selective binding. Therefore, [11C]13 is a potential PET imaging ligand for mGluR2 in different central nervous system-related conditions.

High FLT3 Levels May Predict Sorafenib Benefit in Hepatocellular Carcinoma.

PURPOSE: To identify a predictive biomarker of sorafenib for hepatocellular carcinoma personalized therapy. EXPERIMENTAL DESIGN: The patients treated with or without sorafenib after hepatocellular carcinoma recurrence from multicenters were matched with propensity score matching analysis. The expression levels of Fms-like tyrosine kinase 3 (FLT3) in hepatocellular carcinoma specimens of the matched patients (n = 276) were analyzed by IHC. The optimal cut-off point of FLT3 levels for overall survival (OS) was defined via Cutoff Finder. Subgroup analysis of OS was employed to investigate the association between FLT3 levels and sorafenib benefit. The predictive value was assessed via Cox regression models with an interaction term. Hepatocellular carcinoma and paratumoral normal tissues were used to investigate the expression and copy-number variation of FLT3. Patient-derived xenograft (PDX) models were used to confirm the association between FLT3 levels and sorafenib response. RESULTS: Patients with FLT3-high hepatocellular carcinoma exhibited a superior OS upon sorafenib treatment. High FLT3 levels were predictive of sorafenib benefit in terms of OS (P interaction = 0.00006). Copy-number losses and decreased expression of FLT3 in hepatocellular carcinoma were detected in about 64% of patients. Moreover, the PDXs derived from tumors with high FLT3 levels also displayed a better response to sorafenib. CONCLUSIONS: Sorafenib may be able to delay tumor progression in patients with FLT3-high hepatocellular carcinoma. This potential biomarker needs to be further validated in independent cohorts prior to helping stratify patients for precision therapy in advanced hepatocellular carcinoma.

Synthesis and Characterization of Fluorine-18-Labeled N-(4-Chloro-3-((fluoromethyl-d2)thio)phenyl)picolinamide for Imaging of mGluR4 in Brain.

We have synthesized and characterized [18F]-N-(4-chloro-3-((fluoromethyl-d2)thio)phenyl)-picolinamide ([18F]15) as a potential ligand for the positron emission tomography (PET) imaging of mGluR4 in the brain. Radioligand [18F]15 displays central nervous system drug-like properties, including mGluR4 affinity, potent mGluR4 PAM activity, and selectivity against other mGluRs, as well as sufficient metabolic stability. Radiosynthesis was carried out in two steps. The radiochemical yield of [18F]15 was 11.6 ± 2.9% (n = 7, decay corrected) with a purity of 99% and a molar activity of 84.1 ± 11.8 GBq/µmol. Ex vivo biodistribution studies showed reversible binding of [18F]15 in all investigated tissues including the brain, liver, heart, lungs, and kidneys. PET imaging studies in male Sprague Dawley rats showed that [18F]15 accumulates in the brain regions known to express mGluR4. Pretreatment with the unlabeled mGluR4 PAM compounds 13 (methylthio analogue) and 15 showed significant dose-dependent blocking effects. These results suggest that [18F]15 is a promising radioligand for PET imaging mGluR4 in the brain.

Vessels That Encapsulate Tumor Clusters (VETC) Pattern Is a Predictor of Sorafenib Benefit in Patients with Hepatocellular Carcinoma.

Sorafenib is the most recommended first-line systemic therapy for advanced hepatocellular carcinoma (HCC). Yet there is no clinically applied biomarker for predicting sorafenib response. We have demonstrated that a vascular pattern, named VETC (Vessels that Encapsulate Tumor Clusters), facilitates the release of whole tumor clusters into the bloodstream; VETC-mediated metastasis relies on vascular pattern, but not on migration and invasion of cancer cells. In this study, we aimed to explore whether vascular pattern could predict sorafenib benefit. Two cohorts of patients were recruited from four academic hospitals. The survival benefit of sorafenib treatment for patients with or without the VETC pattern (VETC+ /VETC- ) was investigated. Kaplan-Meier analyses revealed that sorafenib treatment significantly reduced death risk and prolonged overall survival (OS; in cohort 1/2, P = 0.004/0.005; hazard ratio [HR] = 0.567/0.408) and postrecurrence survival (PRS; in cohort 1/2, P = 0.001/0.002; HR = 0.506/0.384) in VETC+ patients. However, sorafenib therapy was not beneficial for VETC- patients (OS in cohort 1/2, P = 0.204/0.549; HR = 0.761/1.221; PRS in cohort 1/2, P = 0.121/0.644; HR = 0.728/1.161). Univariate and multivariate analyses confirmed that sorafenib treatment significantly improved OS/PRS in VETC+ , but not VETC- , patients. Further mechanistic investigations showed that VETC+ and VETC- HCCs displayed similar levels of light chain 3 (LC3) and phosphorylated extracellular signal-regulated kinase (ERK) in tumor tissues (pERK) or endothelial cells (EC-pERK), and greater sorafenib benefit was consistently observed in VETC+ HCC patients than VETC- irrespective of levels of pERK/EC-pERK/LC3, suggesting that the different sorafenib benefit between VETC+ and VETC- HCCs may not result from activation of Raf/mitogen-activated protein kinase kinase (MEK)/ERK and vascular endothelial growth factor (VEGF)A/VEGF receptor 2 (VEGFR2)/ERK signaling or induction of autophagy. Conclusion: Sorafenib is effective in prolonging the survival of VETC+ , but not VETC- , patients. VETC pattern may act as a predictor of sorafenib benefit for HCC.

The SHH/Gli axis regulates CD90-mediated liver cancer stem cell function by activating the IL6/JAK2 pathway.

The cell surface antigen CD90 has recently been established as a promising marker for liver cancer stem cells. This study aimed to investigate potential implications of SHH/Gli signalling in CD90+ liver cancer stem cells. Correlation of the expression of SHH signalling components and CD90 in liver cancer cells and clinical tissues, as well as in enriched CD90+ liver cancer stem cells and the TCGA database, were analysed by quantitative RT-PCR, Western blotting and flow cytometry. Functional analysis was conducted by siRNA-mediated CD90, Gli1 and Gli3 gene knockdown, SHH treatment and application of the JAK2 inhibitor AZD1480 and IL6 neutralizing antibody in CD90+ liver cancer stem cells, followed by cell proliferation, migration, sphere formation and tumorigenicity assays. CD90 expression exhibited a high positive correlation with Gli1 and Gli3 in multiple liver cancer cell lines and human cancerous liver tissues, both of which showed a significant increase in liver cancer. Analysis of TCGA data revealed an association of CD90, Gli1 and Gli3 with a short overall survival and positive correlation between CD90 expression and Gli3 expression level. The stem cell potentials of CD90+ 97L liver cancer cells were greatly impaired by Gli1/3 knockdown with siRNA but enhanced by SHH treatment. Application of the JAK2 inhibitor AZD1480 and IL6 neutralizing antibody showed the CD90 and SHH/Gli-regulated liver cancer stem cell functions were mediated by the IL6/JAK2/STAT3 pathway. The stem cell properties of CD90+ liver cancer cells are regulated by the downstream SHH/Gli and IL6/JAK2/STAT3 signalling pathways.

Measurement of Serum and Hepatic Eicosanoids by Liquid Chromatography Tandem-Mass Spectrometry (LC-MS/MS) in a Mouse Model of Hepatocellular Carcinoma (HCC) with Delivery of c-Met and Activated ß-Catenin by Hepatocyte Hydrodynamic Injection.

BACKGROUND Most forms of cancer, including hepatocellular carcinoma (HCC), are associated with varying degrees of chronic inflammation. The association between the expression of eicosanoids, which are bioactive lipid mediators of inflammation, and HCC remains unknown. The aim of this study was to measure serum and hepatic eicosanoids in a mouse model of HCC with the delivery of c-Met and activated b-catenin by hepatocyte hydrodynamic injection. MATERIAL AND METHODS The HCC mouse model, and normal control mice, were used in this study with co-delivery of human c-Met combined with activated ß-catenin into hepatocytes through hydrodynamic injection. Liquid chromatography tandem-mass spectrometry (LC-MS/MS) analysis was used to measure serum and hepatic eicosanoid levels. RESULTS The combined activation of c-Met and ß-catenin was induced in the HCC mouse model. LC-MS/MS showed that a total of 13 eicosanoids in serum and 12 eicosanoids in liver tissue were significantly increased in the HCC mice, when compared with control mice. CONCLUSIONS In a mouse model of HCC, co-activation of the c-Met and ß-catenin signaling pathway resulted in increased levels of serum and hepatic eicosanoids.

Associating liver partition and portal vein ligation for staged hepatectomy versus conventional two-stage hepatectomy: a systematic review and meta-analysis.

BACKGROUND: It is generally accepted that an insufficient future liver remnant is a major limitation of large-scale hepatectomy for patients with primary hepatocellular carcinoma. Conventional two-stage hepatectomy (TSH) is commonly considered to accelerate future liver regeneration despite its low regeneration rate. Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS), which is characterized by a rapid regeneration, has brought new opportunities. METHODS: Relevant studies were identified by searching the selected databases up to September 2017. Then, a meta-analysis of regeneration efficiency, complication rate, R0 resection ratio, and short-term outcomes was performed. RESULTS: Ten studies, comprising 719 patients, were included. The overall analysis showed that ALPPS was associated with a larger hyperplastic volume and a shorter time interval (P < 0.00001) than TSH. ALPPS also exhibited a higher completion rate for second-stage operations (odds ratio, OR 9.50; P < 0.0001) and a slightly higher rate of R0 resection (OR 1.90; P = 0.11). Interestingly, there was no significant difference in 90-day mortality between the two treatments (OR 1.44; P = 0.35). CONCLUSIONS: These results indicate that compared with TSH, ALPPS possesses a stronger regenerative ability and better facilitates second-stage operations. However, the safety, patient outcomes, and patient selection for ALPPS require further study.