Fluorescence In Situ Hybridization (FISH) Detection of Viral Nucleic Acids in Oncolytic H-1 Parvovirus-Treated Human Brain Tumors.

Fluorescence in situ hybridization (FISH) is a specific, sensitive, accurate, and reliable technique widely applied in both research and clinic. Here we describe the detailed protocol of a FISH method established by us to serve the scientific purposes of the first oncolytic parvovirus clinical trial (ParvOryx01). This trial was launched in Germany in 2011.

Oncolytic H-1 Parvovirus Shows Safety and Signs of Immunogenic Activity in a First Phase I/IIa Glioblastoma Trial.

Oncolytic virotherapy may be a means of improving the dismal prognosis of malignant brain tumors. The rat H-1 parvovirus (H-1PV) suppresses tumors in preclinical glioma models, through both direct oncolysis and stimulation of anticancer immune responses. This was the basis of ParvOryx01, the first phase I/IIa clinical trial of an oncolytic parvovirus in recurrent glioblastoma patients.

Sorafenib Sensitizes Glioma Cells to the BH3 Mimetic ABT-737 by Targeting MCL1 in a STAT3-Dependent Manner.

The oncogenic transcription factor signal transducer and activator of transcription 3 (STAT3) is overactivated in malignant glioma and plays a key role in promoting cell survival, thereby increasing the acquired apoptosis resistance of these tumors. Here we investigated the STAT3/myeloid cell leukemia 1 (MCL1) signaling pathway as a target to overcome the resistance of glioma cells to the Bcl-2-inhibiting synthetic BH3 mimetic ABT-737. Stable lentiviral knockdown of MCL1 sensitized LN229 and U87 glioma cells to apoptotic cell death induced by single-agent treatment with ABT-737 which was associated with an early activation of DEVDase activity, cytochrome c release, and nuclear apoptosis.

Double-faceted mechanism of parvoviral oncosuppression.

The H-1 parvovirus (H-1PV) exerts oncosuppressive action that has two components: oncotoxicity and immunostimulation. While many human tumor cells, including conventional drug-resistant ones, can be killed by H-1PV, some fail to support progeny virus production, necessary for infection propagation in neoplastic tissues. This limitation can be overcome through forced selection of H-1PV variants capable of enhanced multiplication and spreading in human tumor cells.

Regression of glioma in rat models by intranasal application of parvovirus h-1.

Purpose: In previous studies, we have shown that the apathogenic rat parvovirus H-1 (H-1PV) is capable to induce regression of advanced symptomatic rat and human gliomas in a rat model, when the virus was injected in the tumor (intracranially) or intravenously. Infection with H-1PV did not provoke any pathology in nontumor tissue. This study addresses the question whether also intranasal application of this oncolytic virus is suitable and sufficient for treating gliomas in this animal model.

Regression of advanced rat and human gliomas by local or systemic treatment with oncolytic parvovirus H-1 in rat models.

Oncolytic virotherapy is a potential treatment modality under investigation for various malignancies including malignant brain tumors. Unlike some other natural or modified viruses that show oncolytic activity against cerebral neoplasms, the rodent parvovirus H-1 (H-1PV) is completely apathogenic in humans. H-1PV efficiently kills a number of tumor cells without harm to corresponding normal ones.

Oncolytic parvoviruses as cancer therapeutics.

The experimental infectivity and excellent tolerance of some rodent autonomous parvoviruses in humans, together with their oncosuppressive effects in preclinical models, speak for the inclusion of these agents in the arsenal of oncolytic viruses under consideration for cancer therapy. In particular, wild-type parvovirus H-1PV can achieve a complete cure of various tumors in animal models and kill tumor cells that resist conventional anticancer treatments. There is growing evidence that H-1PV oncosuppression involves an immune component in addition to the direct viral oncolytic effect.

Oncolytic rat parvovirus H-1PV, a candidate for the treatment of human lymphoma: In vitro and in vivo studies.

The incidence of lymphomas developing in both immunocompetent and immunosuppressed patients continues to steadily increase worldwide. Current chemotherapy and immunotherapy approaches have several limitations, such as severe side toxicity and selection of resistant cell variants. Autonomous parvoviruses (PVs), in particular the rat parvovirus H-1PV, have emerged as promising anticancer agents.

FGF-2 deficiency does not alter vulnerability of the dopaminergic nigrostriatal system towards MPTP intoxication in mice.

Fibroblast growth factor 2 (FGF-2) was the first growth factor discovered that exerted prominent protective and regenerative effects in an animal model of Parkinson's disease, the MPTP-lesioned dopaminergic nigrostriatal system. To address the putative physiological relevance of endogenous FGF-2 for midbrain dopaminergic neurons, we have analysed densities of tyrosine hydroxylase (TH)-positive cells in the substantia nigra (SN) and TH-positive fibers in the striatum and amygdala of adult FGF-2-deficient mice. We found that densities of TH-immunoreactive (ir) cells in the SN as well as densities of TH-ir fibers in the striatum and amygdala were unaltered as compared with wild-type littermates.

Enlarged infarct volume and loss of BDNF mRNA induction following brain ischemia in mice lacking FGF-2.

FGF-2, a potent multifunctional and neurotrophic growth factor, is widely expressed in the brain and upregulated in cerebral ischemia. Previous studies have shown that intraventricularly or systemically administered FGF-2 reduces the size of cerebral infarcts. Whether endogenous FGF-2 is beneficial for the outcome of cerebral ischemia has not been investigated.

Brain-derived neurotrophic factor improves long-term potentiation and cognitive functions after transient forebrain ischemia in the rat.

We investigated the effect of brain-derived neurotrophic factor (BDNF) on hippocampal long-term potentiation (LTP) and cognitive functions after global cerebral ischemia in the rat. After four-vessel occlusion, BDNF was administered via an osmotic minipump continuously over 14 days intracerebroventricularly. Electrophysiological experiments were performed 14 days after cerebral ischemia.

Inhibition of caspases prevents cell death of hippocampal CA1 neurons, but not impairment of hippocampal long-term potentiation following global ischemia.

An essential role for caspases in programmed neuronal cell death has been demonstrated in various in vitro studies, and synthetic caspase inhibitors have recently been shown to prevent neuronal cell loss in animal models of focal cerebral ischemia and traumatic brain injury, respectively. The therapeutic utility of caspase inhibitors, however, will depend on preservation of both structural and functional integrity of neurons under stressful conditions. The present study demonstrates that expression and proteolytic activity of caspase-3 is up-regulated in the rat hippocampus after transient forebrain ischemia.

Brain-derived neurotrophic factor prevents neuronal death and glial activation after global ischemia in the rat.

The expression of brain-derived neurotrophic factor (BDNF) and its receptor tyrosine kinase B are both increased after global ischemia. Therefore, a protective action of BDNF against the delayed degeneration of vulnerable neurons has been suggested. We have investigated the neuroprotective action of BDNF in global ischemia induced by a four-vessel occlusion in the rat.

Reoxygenation increases the release of reactive oxygen intermediates in murine microglia.

Respiratory burst activity of murine microglial cells was investigated in vitro under normoxic and hypoxic conditions with a chemoluminometric assay. Hypoxia for 24 hours reduced the release of extracellular reactive oxygen intermediates (ROIs), whereas reoxygenation increased the chemoluminescence more than sevenfold. Blockade of potassium channels inhibited the increase of oxidative burst after reoxygenation, indicating that potassium ions, which were increased in the supernatant of hypoxic microglial cells, were involved in this activation process.

Suppression of the oxidative burst in murine microglia by nitric oxide.

The effect of nitric oxide (NO) on the oxidative burst was analyzed in purified murine microglial cells in vitro. The generation of reactive oxygen derivatives was monitored with the use of luminol-dependent chemiluminescence. After inducing the endogenous NO production with interleukin 1beta (IL-1beta) and interferon-gamma (IFN-gamma) the superoxide anion release was significantly reduced, which was reversed by the inhibition of the NO synthase.