Publications by authors named "Tomitaro Onoue"

We have previously demonstrated that a stromal cell-derived factor-1 (SDF-1; CXCL12)/CXCR4 system is involved in the establishment of lymph node metastasis in oral squamous cell carcinoma (OSCC). In this study, we investigated whether the blockade of CXCR4 inhibits lymph node metastasis in B88 OSCC cells. These cells harbour a functional CXCR4 and have the potential to metastasise to the lymph node in vivo.

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Background: We have demonstrated that the stromal cell-derived factor-1 (SDF-1; CXCL12)/CXCR4 system is involved in the establishment of lymph node metastasis in oral squamous cell carcinoma (SCC). Chemotherapy is a powerful tool for the treatment of oral cancer, including oral SCC; however, the effects of chemotherapeutic agents on the expression of CXCR4 are unknown. In this study, we examined the expression of CXCR4 associated with the chemotherapeutic agents in oral cancer cells.

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We have previously shown that a stromal cell-derived factor-1 (SDF-1; CXCL12)/CXCR4 system is involved in the establishment of lymph node metastasis, but not in that of distant metastasis, in oral squamous cell carcinoma (SCC). In this study, we investigated the role of the autocrine SDF-1/CXCR4 system, with a focus on distant metastasis in oral SCC cells. The immunohistochemical staining of SDF-1 and CXCR4 using primary oral SCCs and metastatic lymph nodes showed a significantly higher number of SDF-1-positive cases among the metastatic lymph nodes than among the primary oral SCCs, which was associated with a poor survival rate among those of the former group.

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Epithelial-mesenchymal transition (EMT) refers to critical events occasionally observed during tumor progression, including invasion and metastasis, by which cancer cells acquire a fibroblast-like phenotype. Since the stromal cell-derived factor-1 (SDF-1)/CXCR4 system can facilitate lymph node metastasis in oral squamous cell carcinoma (SCC), we have explored the possibility that this system might be involved in EMT. Oral SCC cells, B88 and HNt, which have functional CXCR4 and lymph node metastatic potential, were found to lose their epithelial cell morphology due to SDF-1.

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In this study, we attempted to use a non-viral gene transfer system, in vivo electroporation, in oral cancer cell B88 xenografts. To evaluate this in vivo gene transfer method, the GFP gene was transfected into xenografts by electroporation. Then, the efficiency of transfection of exogenous p27Kip1 gene by electroporation was confirmed by Western blot analysis.

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S-1 is a new oral antineoplastic agent which can inhibit cell growth and induces apoptosis in certain types of cancer cells including gastric carcinomas, colorectal cancers and salivary gland cancers, but its effect on response of tumor cells to radiation has not been clarified yet. We have reported that S-1 can sensitize human oral cancer cells to radiation, and that S-1 in combination with radiation can exert remarkable effects on decreasing clonogenic survival and in vivo tumor growth. Here, we demonstrate the mechanism of apoptosis enhancing activity by the combination treatment of S-1 and radiation in salivary gland cancer cells.

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Background: The inducible nitric oxide synthase (iNOS) is associated with inflammatory processes and cancer formation through production of nitric oxide (NO). However, the clinical importance of the expression of iNOS in oral cancer remains unclear. In the present study, we examined whether up-regulation of the iNOS gene can affect growth and metastasis of an oral cancer cell line (B88t cell) in vitro and in vivo.

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We evaluated the orally administered S-1, in combination with ionizing radiation both in vivo and in vitro against human oral cancer cell lines. Human oral cancer cell lines were used as subcutaneous xenografts in nude mice. S-1 (10 mg/kg) was administered orally 1 h before radiation treatments (1.

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It is well known that loss of the cyclin-dependent kinase inhibitor p27Kip1 protein correlates with the poor prognosis of various cancers including oral squamous cell carcinoma (SCC). Posttranslational degradation of p27Kip1 protein is mediated by phosphorylation of Thr-187 of p27Kip1 protein, which follows ubiquitination. In this study, we constructed an expression vector expressing mutant type p27Kip1 gene (pcDNA3.

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