Objective-Brain arteriovenous malformations (bAVM) are an important cause of hemorrhagic stroke. The underlying mechanisms are not clear. No animal model for adult bAVM is available for mechanistic exploration. Patients with Hereditary Hemorrhagic Telangiectasia Type2 (HHT2) with activin receptor-like kinase 1 (ALK1; ACVRL1) mutations have a higher incidence of bAVM than the general population. We tested the hypothesis that VEGF stimulation with regional homozygous deletion of Alk1 induces severe dysplasia in the adult mouse brain, akin to human bAVM.Methods-Alk1 2f/2f (exons 4-6 flanked by loxP sites) and wild-type (WT) mice (8-10 weeks old) were injected with Ad-Cre (2×10 7 PFU, adenoviral vector expressing Cre recombinase) and AAV-VEGF (2×10 9 genome copies, adeno-associated viral vectors expressing VEGF) into the basal ganglia. At 8 weeks, blood vessels were analyzed.Results-Gross vascular irregularities were seen in Alk1 2f/2f mouse brain injected with Ad-Cre and AAV-VEGF. The vessels were markedly enlarged with abnormal patterning resembling aspects of the human bAVM phenotype, displayed altered expression of the arterial and venous markers (EphB4 and Jagged-1), and showed evidence of arteriovenous shunting. Vascular irregularities were not seen in similarly treated WT mice.Interpretation-Our data indicate that post-natal, adult formation of the human disease bAVM is possible, and that both genetic mutation and angiogenic stimulation are necessary for lesion development. Our work not only provides a testable adult mouse bAVM model for the first time, but also suggests that specific medical therapy can be developed to slow bAVM growth and potentially stabilize the rupture-prone abnormal vasculature.

Ovarian cancer shows high mortality due to development of resistance to chemotherapy and relapse. Cancer stem cells (CSCs) have been suggested to be a major contributor in developing drug resistance and relapse in ovarian cancer. In this study, we isolated CSCs through sphere culture of A2780, SKOV3, OVCAR3 epithelial ovarian cancer cells and primary ovarian cancer cells from patients. We identified heat-stable factors secreted from ovarian CSCs stimulated migration and proliferation of CSCs. Mass spectrometry and ELISA analysis revealed that lysophosphatidic acid (LPA) was significantly elevated in CSC culture media compared with non-CSC culture media. Treatment of CSCs with LPA resulted in augmented CSC characteristics such as sphere-forming ability, resistance to anticancer drugs, tumorigenic potential in xenograft transplantation, and high expression of CSC-associated genes, including OCT4, SOX2, and aldehyde dehydrogenase 1. Treatment of CSCs with LPA receptor 1-specific inhibitors or silencing of LPA receptor 1 expression abrogated the LPA-stimulated CSC properties. Autotaxin, an LPAproducing enzyme, is highly secreted from ovarian CSCs, and pharmacological inhibition or knockdown of autotaxin markedly attenuated the LPA-producing, tumorigenic, and drug resistance potentials of CSCs. Clinicopathological analysis showed a significant survival disadvantage of patients with positive staining of autotaxin. In addition, we further identified that AKT1 activity was upregulated in ovarian CSCs through an LPA-dependent mechanism and silencing of AKT1 expression led to suppression of CSC characteristics. These results suggest that autotaxin-LPA-LPA receptor 1-AKT1 signaling axis is critical for maintaining CSC characteristics through an autocrine loop and provide a novel therapeutic target for ovarian CSCs. STEM CELLS 2016;34:551-564 SIGNIFICANCE STATEMENTEpithelial ovarian cancer shows high mortality due to development of resistance to chemotherapy and recurrence of cancer cells. Cancer stem cells have been implicated in drug resistance and relapse of ovarian cancer. Our findings suggested that ATX-LPA-LPAR1-AKT1 signaling axis is critical for maintenance of cancer stem-like characteristics in an ovarian cancer stem cell subpopulation through an autocrine loop. Inhibiting ATX-LPA-LPAR1-AKT1 signaling axis by chemical inhibitor or knockdown of gene expression increased the sensitivity of cancer stem cells to chemotherapeutic reagents. Our findings provide therapeutic opportunities for development of relapse-free treatment of epithelial ovarian cancer.

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Although Korean cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) mutation carriers show similar clinical and MRI findings, these abnormalities appear less frequently than in other populations. Relatively frequent microbleedings on gradient echo imaging suggest that treatment should be individualized according to MRI findings. The novel mutation of R75P, not involving a cysteine residue, is related to less frequent involvement of the anterior temporal area, thus broadening the spectrum of CADASIL.

ObjectiveTo compare the effect of extracorporeal shock-wave therapy (ESWT) applied at the muscle belly and myotendinous junction on spasticity in the upper and lower limbs of chronic stroke patients.MethodsOf the 151 patients, a total of 80 patients with stroke-induced spasticity on the elbow flexor and 44 patients on the knee flexor were enrolled for a prospective, randomized clinical trial. The patients were divided into control, muscle belly, and myotendinous junction groups, and a total of three ESWT sessions (0.068–0.093 mJ/mm2, 1,500 shots) were conducted at one per week. A Modified Ashworth Scale (MAS) and Modified Tardieu Scale (MTS) were collected at the baseline and at 1 week after each session.ResultsAfter interventions, the MAS and MTS of both the belly and the junction groups showed positive effects from the ESWT on spasticity in the elbow and knee flexors, but the control group did not. The results also tended to improve after each session until the entire intervention was completed. However, there was no significant difference between the belly and junction groups.ConclusionESWT could be effective for treating chronic spasticity after stroke when applied to muscle belly or myotendinous junction.