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Hatakeyama S.,Oyokyo Kidney Research Institute | Yamamoto H.,Oyokyo Kidney Research Institute | Ohyama C.,Hirosaki University
Methods in Enzymology | Year: 2010

Animal experiments are necessary to confirm and demonstrate the reliability of the results of in vitro assays and to reveal any unexpected effects in the living body. Tumor invasion and metastasis consist of multistep and complex cascades. Moreover, conflictive interactions between cancer cells and host immune system exist in the living body. Therefore, tumor formation assay is an essential technique in tumor biology. Methods used in tumor formation assay include injection and inoculation, and considerable skill is required to perform these basic techniques. Injections and inoculations are categorized according to the target site: intraperitoneal (IP), intravenous (IV), subcutaneous (SC), footpad (FP), and targeted organ inoculation. Tumor cell injections and inoculations are standard methods for the evaluation of the malignant potential of cancer cells. IP injection is a useful and uncomplicated method for drug administration, SC inoculation is used to evaluate tumor growth and size, FP inoculation to estimate lymph nodule metastasis, and IV injection into the tail vein to evaluate the metastatic potential for lung colonization. Using immune-deficiency mice, we can address possible roles of carbohydrate antigens against host immune system. In this chapter, we describe details of the materials and methods that can be used for injection (IP and IV) and inoculation (SC, FP, testis, and prostate) in mice. © 2010 Elsevier Inc. Source

Tsuboi S.,Oyokyo Kidney Research Institute | Tsuboi S.,Hirosaki University
Trends in Glycoscience and Glycotechnology | Year: 2013

The O-glycan branching enzyme, core2 β-1,6-N-acetylglucosaminyltransferase (C2GnT) forms O-glycans containing a branch of β-1,6-linkage of N-acetylglucosamine and N-acetylgalctosamine (core2 O-glycans) on cell-surface glycoproteins. It was reported that expression of C2GnT, a key enzyme for core2 O-glycans expression, was closely correlated with high-metastatic phenotypes of numbers of cancers. Recently, it has been revealed that C2GnT-expressing cancer cells synthesize core2 O-glycans which have immunosuppressive functions against natural killer (NK) cell immunity by using their cell-surface core2 O-glycans, resulting in acquiring high-metastatic phenotypes. C2GnTexpressing cancer cells have two different types of immunosuppressive functions against NK cell immunity, molecular shield and tumor-ligand masking. Here, we highlight recent advances in our understanding of the detailed molecular mechanisms of those immunosuppressive functions of core2 O-glycans. © 2013 FCCA (Forum: Carbohydrates Coming of Age). Source

Odagiri G.,Hirosaki University | Sugawara N.,Hirosaki University | Kikuchi A.,Hirosaki University | Takahashi I.,Hirosaki University | And 4 more authors.
Annals of General Psychiatry | Year: 2011

Over 290,000 patients are undergoing hemodialysis (HD) in Japan. With old age, the odds of undergoing HD treatment sharply increase, as does the prevalence of cognitive impairment. The aim of the present work was to assess cognitive impairment in HD patients and its relation to clinical characteristics.Methods: Using a cross-sectional design, we administered the Mini-Mental State Examination (MMSE) to 154 HD outpatients and 852 participants from the Iwaki Health Promotion Project 2010, representing the general population.Results: The prevalence of cognitive impairment based on the MMSE was 18.8% in HD patients. HD patients showed a higher prevalence of cognitive impairment in older groups (50 years and older). In a logistic regression model with age, gender and amount of education as covariates, undergoing HD was a significant independent factor (OR = 2.28, 95% CI 1.33 to 3.94) associated with a lower MMSE score. Among HD patients, we found that level of education was associated with MMSE score.Conclusions: There is a high prevalence of cognitive impairment among HD patients that has adverse implications for hospitalization and shortens their life expectancy. HD treatment was an independent risk factor for cognitive impairment. Clinicians should carefully monitor and treat cognitive impairment in HD patients. Further studies are required to determine the reasons for cognitive impairment in HD patients. © 2011 Odagiri et al; licensee BioMed Central Ltd. Source

Tsuboi S.,Oyokyo Kidney Research Institute | Tsuboi S.,Hirosaki University | Hatakeyama S.,Hirosaki University | Ohyama C.,Hirosaki University | Fukuda M.,Sanford Burnham Institute for Medical Research
Trends in Molecular Medicine | Year: 2012

Despite the high prevalence of metastatic cancers and the poor outcome for patients, the processes of tumor metastasis still remain poorly understood. It has been shown that cell-surface carbohydrates attached to proteins through the amino acids serine or threonine (O-glycans) are involved in tumor metastasis, with the roles of O-glycans varying depending on their structure. Core2 O-glycans allow tumor cells to evade natural killer (NK) cells of the immune system and survive longer in the circulatory system, thereby promoting tumor metastasis. Core3 O-glycans or O-mannosyl glycans suppress tumor formation and metastasis by modulating integrin-mediated signaling. Here, we highlight recent advances in our understanding of the detailed molecular mechanisms by which O-glycans promote or suppress tumor metastasis. © 2012 Elsevier Ltd. Source

Sutoh Yoneyama M.,Hirosaki University | Hatakeyama S.,Hirosaki University | Habuchi T.,Akita University | Inoue T.,Akita University | And 6 more authors.
European Journal of Cell Biology | Year: 2014

To investigate the molecular mechanisms of cancer metastasis, we have isolated a high-metastatic bladder cancer cell subpopulation from a low-metastatic cell line by using an in vivo selection system. Cells in the subpopulation showed a high ability to form invadopodia, the filamentous actin (F-actin)-based membrane protrusions that play an essential role in cancer cell invasion. Analysis of the gene expression profile revealed that the expression of an intermediate filament (IF) protein, vimentin and a cytoskeletal linker protein, plectin was up-regulated in the high-metastatic subpopulation compared with the low metastatic cell line. Here we report a novel role of vimentin IF and plectin in metastasis. In invasive bladder cancer cells, the vimentin IF-plectin-invadopodia F-actin link was formed. Disruption of this link severely impaired invadopodia formation, reducing the capacities of extracellular matrix degradation, transendothelial migration and metastasis. In addition, the vimentin assembly into the filaments was required for invadopodia formation. Our results suggest that plectin anchoring invadopodia to vimentin IF scaffolds and stabilizes invadopodia, which is a critical molecular process for cancer cell invasion and extravasation for metastasis. © 2014 Elsevier GmbH. Source

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