Kyoko Hirota

Kanazawa University, Kanazawa, Ishikawa, Japan

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Publications (6)11.08 Total impact

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    ABSTRACT: Hirota K, Wakisaka N, Sawada-Kitamura S, Kondo S, Endo K, Tsuji A, Murono S & Yoshizaki T (2012) Histopathology Lymphangiogenesis in regional lymph nodes predicts nodal recurrence in pathological N0 squamous cell carcinoma of the tongue Aims:  Cancer cells induce de-novo lymphatic vessel growth within draining lymph nodes before they metastasize. The aim of this study was to retrospectively evaluate lymph node lymphangiogenesis before the establishment of nodal recurrence in squamous cell carcinoma (SCC) of the tongue. Methods and results:  Surgical specimens from 28 patients with pT2-T3N0M0 SCC of the tongue after local excision with supraomohyoid neck dissection were studied by immunohistochemistry. Intranodal lymphatic endothelium was highlighted by podoplanin staining to evaluate lymphatic vessel counts (LVCs). Primary tumour sections were examined for the expression of lymphangiogenic factors: vascular endothelial growth factor (VEGF)-C and VEGF-D. LVCs in regional lymph nodes were significantly increased in the cases with nodal recurrence (P = 0.0013). Simultaneous increases in VEGF-C and VEGF-D expression were significantly associated with both an increase in LVC in regional lymph nodes (P = 0.0001) and a decrease in the rate of survival without nodal recurrence (P = 0.016). Conclusions:  Knowing the status of lymphangiogenesis in the regional pN0 lymph nodes in tongue cancer would help in predicting which patients will develop nodal recurrence. The use of a therapeutic approach which blocks lymphangiogenic factors, such as VEGF-C and VEGF-D, may be beneficial in suppressing the lymphatic spread of tongue cancer with intense intranodal lymphangiogenesis.
    Histopathology 06/2012; · 2.86 Impact Factor
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    ABSTRACT: The contribution of the lymphatic system to tumor metastasis is being increasingly appreciated through studies of human cancers. As the biological behavior of nasopharyngeal carcinoma (NPC) depends on its nodal status, patients with advanced nodal status show a higher tendency toward a poor outcome. Here, we examined the role of lymphangiogenesis on lymphatic spread of NPC. We also evaluated the involvement of vascular endothelial growth factor (VEGF)-C/VEGF receptor 3 (VEGFR3) signaling pathway on lymphangiogenesis in NPC. Furthermore, we tested whether Epstein-Barr virus (EBV)-latent membrane protein (LMP) 1 induces VEGF-C. Forty-one patients with NPC were evaluated for expressions of VEGF-C and its receptor, VEGFR3, and LMP1 proteins and lymphatic vessel counts (LVC) highlighted by anti-podoplanin employing immunohistochemistry. The VEGF-C induction by LMP1 was then tested with Western blotting and enzyme-linked immunosorbent assay in vitro. The LVC and VEGF-C expression were significantly higher in cases with advanced regional lymph node metastasis (N2,3) than those with no or limited lymph node involvement (N0,1) (p=0.0380 and p=0.0109, respectively). In VEGF-C/VEGFR3-positive cases, the LVC were significantly increased compared with VEGF-C/VEGFR3-negative cases (p=0.0007). However, LMP1 expression did not show significant associations with LVC and VEGF-C-expression scores (p=0.1210 and p=0.1324, respectively). Induction of VEGF-C protein by LMP1 was not detected in vitro. These results suggest the involvement of the VEGF-C/VEGFR3 axis in the induction of lymphangiogenesis which results in lymphatic spread of NPC. However, EBV-LMP1 was not associated with the mechanism.
    Oral Oncology 02/2012; 48(8):703-8. · 2.70 Impact Factor
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    ABSTRACT: To image olfactory nerve regeneration in vivo using a high-resolution gamma cam- era and radiography after nasal administration of thallium-201 (olfacto-scintigraphy). Six Wistar rats were trained to avoid the smell of cycloheximide as a test of olfactory function. The olfactory nerve fibers of 3 rats were then carefully transected bilaterally with a Teflon knife, avoiding damage to the olfactory bulbs. The remaining 3 rats underwent sham operations and were used as controls. Steel wires were implanted in the left olfactory bulb of each rat for locating the bulbs with plain X-rays. The rats were assessed 2, 14, 28, and 42 d after the olfactory nerve transection or sham operation for their ability to detect odours and for transport of 201Tl to the olfactory bulb area 8 h after nasal administration of 201Tl. Both transport of 201Tl to the olfactory bulb area (p < 0.04) and ability to detect odours (p < 0.04) significantly increased with a time course after olfactory nerve transection. 201Tl transport to the olfactory bulb may be useful to visually assess olfactory ability in vivo. We plan to test olfacto-scintigraphy clinically by nasal administration of 201Tl in patients with posttraumatic olfactory loss.
    Rhinology 12/2009; 47(4):460-4. · 1.72 Impact Factor
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    ABSTRACT: The curry odorant of the odor stick identification test for Japanese (OSIT-J) is useful in screening for olfactory impairment in Japanese subjects. The present study was designed to determine the most useful odorant of the OSIT-J in screening for olfactory impairment in Japanese subjects. We studied olfactory impairment screening with the OSIT-J in 83 participants (49 male, 34 female; average age 50 years) in an executive check-up at NTT West Kanazawa Hospital. Olfactory discrimination acuity was evaluated with three odorants of the OSIT-J (rose, curry, and sweaty-smelling clothes), each known to be significantly correlated with the assessment of the Japanese standard olfaction test (T&T olfactometer). Those participants who did not score full marks in tests with the three odors were assessed with another nine odorants of the OSIT-J. The positive predictive value was 100% in the screening with the curry odorant. In 38 participants who did not identify all three odors correctly, the identification of the curry odor was significantly correlated with the scores for all 12 odors (p<0.005). Identification of the curry odor was not significantly correlated with identification of the menthol odor of OSIT-J.
    Acta oto-laryngologica. Supplementum 06/2009;
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    ABSTRACT: To present an extremely rare case of large Delphian node metastasis preceding primary laryngeal cancer. A 74-year-old male who noted a mass on the lower anterior neck and consulted our department immediately. The mass rapidly grew to 6cm from 2cm in diameter within 2 months after the initial presentation. Fiberoptic laryngoscopy was unremarkable. Surgical excision of the lesion showed well differentiated squamous cell carcinoma with invasion into the surrounding tissues. Postoperative radiotherapy was added. During follow-up after those treatments, thickening of the right vocal cord was observed, which gradually became more apparent. Total laryngectomy was performed 13 months after the initial operation. Delphian node metastasis is included in the differential diagnosis in a case of rapidly increasing mass in the anterior neck.
    Auris, nasus, larynx 04/2009; 36(5):614-7. · 0.58 Impact Factor
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    ABSTRACT: Although olfactory nerve damage is a contributing factor in the diagnosis of posttraumatic olfactory loss, at present, there are no methods to directly assess injury to these nerves. We have shown that following olfactory nerve injury in mice, thallium-201 (201 Tl) transport from the nasal cavity to the olfactory bulb decreases. To determine if olfactory function after nerve injury could be assessed with nasal administration of 201 Tl, we measured the correlation between odor detection ability (ODA) and the rate of transport of 201 Tl in olfactory nerves. Both ODA and 201 Tl transport were measured after bilateral olfactory nerve transection for a 4-week period. Cycloheximide solution was used for ODA against tap water. 201 Tl transport was measured as the ratio of radioactivity in the nasal cavity and olfactory bulb with gamma spectrometry. There was a significant correlation between ODA and the rate of 201 Tl transport in the olfactory nerve. These findings suggest that olfactory function after nerve injury can be objectively evaluated with the nasal administration of 201 Tl.
    Chemical Senses 07/2008; 33(7):633-7. · 3.22 Impact Factor