Munekazu Nakaichi

ortho-Carboranyl Glycosides for the Treatment of Cancer by Boron Neutron Capture Therapy

Distinct biological properties of the ortho-carboranyl (1,2-dicarba-closo-dodecaboranyl) glycosides 1, 2 and 3 were evaluated to estimate the suitability of these compounds for cancer treatment by boron neutron capture therapy. The boron uptake into B16-Melanoma cells was significantly higher by incubating the cells with aqueous solutions of carboranyl glucoside 1 (11.2 ppm after 3h), lactoside 2 (13.2 ppm after 12h) and maltoside 3 (20.0 ppm after 24h) compared with solutions of clinically used p-boronophenylalanine (BPA) 5 (3.1 ppm after 24h). Carboranyl maltoside 3 was more effective than boron-10 enriched 5 in killing C-6 rat glioma cells by incubating the cells with the compound and subsequent treatment with thermal neutrons. 3 was also administrated iv, in concentrations of 25 mg boron/kg body weight to rats bearing brain tumors. After a period of 4h after administration the concentration of boron in the tumor tissue was 3.0 ppm.

Carboranyl bisglycosides for the treatment of cancer by boron neutron capture therapy.

Boron neutron capture therapy is a special type of radiotherapy for the treatment of cancer by using boron compounds. Problems often arise from the low water solubility of these compounds, their unselective uptake into the cancer cells, and their toxicity. Here we describe the novel water‐soluble ortho‐carboranyl bisglycosides 7 and 10 containing either lactose or glucose and the mixed bisglycosides 1 and 28 containing glucose, mannose, and galactose. The carboranyl bisglycosides show almost no toxicity toward bronchial carcinoma cells of line A549 up to a concentration of 0.50 mM. As anticipated, these compounds exhibit nearly no uptake into C6 glioma cells; they can therefore be used for a selective delivery into malignant cells by using conjugates of glycohydrolases and monoclonal antibodies which bind to tumor‐associated antigens, since by enzymatic hydrolysis the bisglycosides are transformed into lipophilic compounds.

GM2 Gangliosidosis Variant 0 (Sandhoff‐Like Disease) in a Family of Toy Poodles

BACKGROUND GM2 gangliosidosis variant 0 (human Sandhoff disease) is a lysosomal storage disorder caused by deficiencies of acid β-hexosaminidase (Hex) A and Hex B because of an abnormality of the β-subunit, a common component in these enzyme molecules, which is coded by the HEXB gene. OBJECTIVE To describe the clinical, pathological, biochemical, and magnetic resonance imaging (MRI) findings of Sandhoff-like disease identified in a family of Toy Poodles. ANIMALS Three red-haired Toy Poodles demonstrated clinical signs including motor disorders and tremor starting between 9 and 12 months of age. The animals finally died of neurological deterioration between 18 and 23 months of age. There were some lymphocytes with abnormal cytoplasmic vacuoles detected. METHODS Observational case study. RESULTS The common MRI finding was diffuse T2-hyperintensity of the subcortical white matter in the cerebrum. Bilateral T2-hyperintensity and T1-hypointensity in the nucleus caudatus, and atrophic findings of the cerebrum and cerebellum, were observed in a dog in the late stage. Histopathologically, swollen neurons with pale to eosinophilic granular materials in the cytoplasm were observed throughout the central nervous system. Biochemically, GM2 ganglioside had accumulated in the brain, and Hex A and Hex B were deficient in the brain and liver. Pedigree analysis demonstrated that the 3 affected dogs were from the same family line. CONCLUSIONS AND CLINICAL IMPORTANCE The Sandhoff-like disease observed in this family of Toy Poodles is the 2nd occurrence of the canine form of this disease and the 1st report of its identification in a family of dogs.

Clinical observations of Babesia gibsoni infection with low parasitaemia confirmed by PCR in dogs.

2004). In preliminary experiments, this PCR was able to detect approximately 10 B gibsoni-infected red blood cells in 1 μl of peripheral blood. All 35 animals with B gibsoni infection were positive by the PCR. To confirm the PCR findings, nucleotide sequences of randomly selected products of the B gibsoni-specific PCR were determined by direct sequence analysis, using the method described by Inokuma and others (2003). All the analysed sequences showed 100 per cent homology with B gibsoni Asia-1 (GenBank accession number AF175300). The animals with IMHA showed an acute onset of signs similar to those of B gibsoni infection, such as haemolytic and regenerative anaemia, icterus, anorexia or haematuria, at presentation. All eight animals with IMHA were found to be negative for B gibsoni infection by PCR. The information obtained for the 35 babesiosis cases and eight IHMA cases included histories and the findings of physical examination, complete blood counts, serum biochemical analysis and abdominal radiography. To compare the data from the dogs with low parasitaemia with the data from those with moderate to severe parasitaemia or with IMHA cases, chisquared tests and one-way analysis of variance were performed by using StatView v 5.0 (Hulinks). When the clinical and laboratory findings of the Babesia-infected animals showing low parasitaemia were compared with those of the dogs with moderate to severe parasitaemia, there were no significant differences between the two groups (Table 1). Although the numbers of dogs that showed icterus and the mean total bilirubin level in dogs with more severe parasitaemia were slightly higher than those of the dogs with low parasitaemia, the differences were not significant. Oxidative damage to erythrocytes induced by B gibsoni infection is thought to result in severe anaemia even in the presence of low parasitaemia (Otsuka and others 2002). Overall, the degree of parasitaemia in the B gibsoni-infected dogs did not relate to the clinical and laboratory findings. The clinical and laboratory findings in the dogs with B gibsoni infection with low parasitaemia were also compared with Clinical observations of Babesia gibsoni infection with low parasitaemia confirmed by PCR in dogs

Primary chondrosarcoma in the skull of a dog.

Chondrosarcoma of the skull is a rare primary malignant tumor that is slow-growing, but locally aggressive. A 5-year-old, golden retriever was presented to our hospital with a swelling in the left side of her head, and the swelling had slowly enlarged over the previous month. There were no significant changes on the neurological examination. A computed tomography scan revealed a large mass involving bone destruction and prominent matrix mineralization. T1-weighted magnetic resonance imaging showed a slightly low-signal intensity area and a T2-weighted image revealed marked, high-signal intensity. There was compression of the adjacent brain parenchyma. Histopathological examination confirmed the lesion to be a chondrosarcoma.

Malignant mixed tumor in the salivary gland of a cat.

The presence of a malignant mixed tumor, also known as a carcinosarcoma, in the salivary gland is very rare. Such tumors, which are typically aggressive, are characterized by the presence of carcinomatous and sarcomatous components. A 9-year-old neutered female domestic short-haired cat presented with swelling in the right mandibular lesion that had rapidly enlarged over the previous 3 weeks. Physical examination revealed a large, fluctuated and painless subcutaneous swelling that was associated with a firm mass. Radiographs of the head revealed a soft-tissue density that involved faint circular calcific opacity. Contrast-enhanced computed tomography revealed that the peripheral capsulated cystic area had a contrast enhanced region without bone lysis. The cat received a total excision of the mass and postoperative radiotherapy. Histopathological analysis of the mass revealed that it was a malignant mixed tumor. Metastasis to the lung was discovered 7 weeks later, at which time treatment was stopped.

Application of ventriculoperitoneal shunt as a treatment for hydrocephalus in a dog with syringomyelia and Chiari I malformation

A twenty-month-old Chihuahua male dog was presented to us suffering with ataxia. Based on the physical examination, X-ray and magnetic resonance imaging (MRI) examinations, we diagnosed the dog with hydrocephalus, Chiari I malformation and syringomyelia. Treatment consisted of internal medical treatment and the placement of a ventriculoperitoneal (VP) shunt. The ventricular dilatation was relieved and the dog improved neurologically; however, the Chiari I malformation and syringomyelia remained after surgically positioning the VP shunt.

Detection of centrosome amplification as a surrogate marker of dysfunction in the p53 pathway -p53 gene mutation or MDM2 overexpression.

Abstract In human and canine cancers, the inactivation of p53 protein as well as p53 gene mutation and MDM2 overexpression result in centrosome amplification that in turn contributes to chromosomal instability. To explore the usefulness of the detection of centrosome amplification as a surrogate marker of dysfunction in the p53 pathway, we systematically analysed centrosome amplification, p53 overexpression, p53 gene mutation and MDM2 overexpression in canine tumours. Centrosome amplification was detected in 16 of 51 (31%) naturally developing tumours in dogs. All the tumour specimens with aberrations in the p53 pathway, including p53 overexpression, p53 gene mutation or MDM2 overexpression, showed centrosome amplification, suggesting that the detection of centrosome amplification could serve as a preliminary surrogate marker of dysfunction in the p53 pathway.

Oncolytic reovirus therapy: Pilot study in dogs with spontaneously occurring tumours

Oncolytic virotherapy is a novel treatment involving replication-competent virus in the elimination of cancer. We have previously reported the oncolytic effects of reovirus in various canine cancer cell lines. This study aims to establish the safety profile of reovirus in dogs with spontaneously occurring tumours and to determine a recommended dosing regimen. Nineteen dogs with various tumours, mostly of advanced stages, were treated with reovirus, ranging from 1.0 × 108 to 5.0 × 109 TCID50 given as intratumour injection (IT) or intravenous infusion (IV) daily for up to 5 consecutive days in 1 or multiple treatment cycles. Adverse events (AEs) were graded according to the Veterinary Cooperative Oncology Group- Common Terminology Criteria for Adverse Events (VCOG-CTCAE) v1.1 guidelines. Viral shedding, neutralizing anti-reovirus antibody (NARA) production and immunohistochemical (IHC) detection of reovirus protein in the tumours were also assessed. AE was not observed in most dogs and events were limited to Grade I or II fever, vomiting, diarrhoea and inflammation of the injected tumour. No infectious virus was shed and all dogs had elevated NARA levels post-treatment. Although IHC results were only available in 6 dogs, 4 were detected positive for reovirus protein. In conclusion, reovirus is well-tolerated and can be given safely to tumour-bearing dogs according to the dosing regimen used in this study without significant concerns of viral shedding. Reovirus is also potentially effective in various types of canine tumours.

Aldehyde dehydrogenase activity helps identify a subpopulation of murine adipose-derived stem cells with enhanced adipogenic and osteogenic differentiation potential

AIM To identify and characterize functionally distinct subpopulation of adipose-derived stem cells (ADSCs). METHODS ADSCs cultured from mouse subcutaneous adipose tissue were sorted fluorescence-activated cell sorter based on aldehyde dehydrogenase (ALDH) activity, a widely used stem cell marker. Differentiation potentials were analyzed by utilizing immunocytofluorescece and its quantitative analysis. RESULTS Approximately 15% of bulk ADSCs showed high ALDH activity in flow cytometric analysis. Although significant difference was not seen in proliferation capacity, the adipogenic and osteogenic differentiation capacity was higher in ALDHHi subpopulations than in ALDHLo. Gene set enrichment analysis revealed that ribosome-related gene sets were enriched in the ALDHHi subpopulation. CONCLUSION High ALDH activity is a useful marker for identifying functionally different subpopulations in murine ADSCs. Additionally, we suggested the importance of ribosome for differentiation of ADSCs by gene set enrichment analysis.