Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Yuji Kozuka is active.

Publication


Featured researches published by Yuji Kozuka.


American Journal of Pathology | 2011

Tenascin C Induces Epithelial-Mesenchymal Transition–Like Change Accompanied by SRC Activation and Focal Adhesion Kinase Phosphorylation in Human Breast Cancer Cells

Keiki Nagaharu; Xinhui Zhang; Toshimichi Yoshida; Daisuke Katoh; Noriko Hanamura; Yuji Kozuka; Tomoko Ogawa; Taizo Shiraishi; Kyoko Imanaka-Yoshida

Tenascin C (TNC) is an extracellular matrix glycoprotein up-regulated in solid tumors. Higher TNC expression is shown in invading fronts of breast cancer, which correlates with poorer patient outcome. We examined whether TNC induces epithelial-mesenchymal transition (EMT) in breast cancer. Immunohistochemical analysis of invasive ductal carcinomas showed that TNC deposition was frequent in stroma with scattered cancer cells in peripheral margins of tumors. The addition of TNC to the medium of the MCF-7 breast cancer cells caused EMT-like change and delocalization of E-cadherin and β-catenin from cell-cell contact. Although amounts of E-cadherin and β-catenin were not changed after EMT in total lysates, they were increased in the Triton X-100-soluble fractions, indicating movement from the membrane into the cytosol. In wound healing assay, cells were scattered from wound edges and showed faster migration after TNC treatment. The EMT phenotype was correlated with SRC activation through phosphorylation at Y418 and phosphorylation of focal adhesion kinase (FAK) at Y861 and Y925 of SRC substrate sites. These phosphorylated proteins colocalized with αv integrin-positive adhesion plaques. A neutralizing antibody against αv or a SRC kinase inhibitor blocked EMT. TNC could induce EMT-like change showing loss of intercellular adhesion and enhanced migration in breast cancer cells, associated with FAK phosphorylation by SRC; this may be responsible for the observed promotion of TNC in breast cancer invasion.


Oncogenesis | 2013

Binding of αvβ1 and αvβ6 integrins to tenascin-C induces epithelial–mesenchymal transition-like change of breast cancer cells

D Katoh; Keiki Nagaharu; Naoshi Shimojo; Noriko Hanamura; M Yamashita; Yuji Kozuka; Kyoko Imanaka-Yoshida; Toshimichi Yoshida

Tenascin-C (TNC), a large hexameric extracellular glycoprotein, is a pleiotropic molecule with multiple domains binding to a variety of receptors mediating a wide range of cellular functions. We earlier reported that TNC induces epithelial–mesenchymal transition (EMT)-like change in breast cancer cells. In the present study, we clarified TNC receptor involvement in this process. Among integrins previously reported as TNC receptors, substantial expression of αv, α2, β1 and β6 subunits was detected by quantitative PCR and immunoblotting in MCF-7 cells. Integrin β6 mRNA was remarkably upregulated by transforming growth factor (TGF)-β1 treatment, and protein expression was prominently increased by additional exposure to TNC. Immunofluorescent labeling demonstrated integrin αvβ6 accumulation in focal adhesions after TNC treatment, especially in combination with TGF-β1. The α2 and β1 subunits were mainly localized at cell–cell contacts, αv being found near cell cluster surfaces. Immunoprecipitation showed increase in αvβ1 heterodimers, but not α2β1, after TNC treatment. Activated β1 subunits detected by an antibody against the Ca2+-dependent epitope colocalized with αv in focal adhesion complexes, associated with FAK phosphorylation at tyrosine 925. Neutralizing antibodies against αv and β1 blocked EMT-like change caused by TNC alone. In addition, anti-αv and combined treatment with anti-β1 and anti-αvβ6 inhibited TGF-β1/TNC-induced EMT, whereas either of these alone did not. Integrin subunits αv, β1 and β6, but not α2, bound to TNC immobilized on agarose beads in a divalent cation-dependent manner. Treatments with neutralizing antibodies against β1 and αvβ6 reduced αv subunit bound to the beads. Immunohistochemistry of these receptors in human breast cancer tissues demonstrated frequent expression of β6 subunits in cancer cells forming scattered nests localized in TNC-rich stroma. These findings provide direct evidence that binding of αvβ6 and αvβ1 integrins to TNC as their essential ligand induces EMT-like change in breast cancer cells.


Pathology International | 2002

Esophageal anthracosis: Lesion mimicking malignant melanoma

Tetsuya Murata; Takazumi Imai; Kenichiro Hoshino; Masami Kato; Kenji Tanigawa; Tetsuya Higuchi; Yuji Kozuka; Rie Inoue; Masatoshi Watanabe; Taizo Shiraishi; Kaiyo Takubo

A case of anthracosis of the esophagus is reported. The patient was a previously healthy 69‐year‐old Japanese woman. A black and slightly elevated lesion was detected in her esophagus by upper gastroesophageal fiberoscopic examination. Endoscopically, the lesion looked like malignant melanoma. Thoracic esophagotomy was then performed. Histological examination revealed a pigmented lesion beneath the mucosal epithelial layer. The lesion consisted of an aggregation of histiocytes containing an abundance of tiny black pigments. A few mature lymphocytes and plasma cells were also evident in the periphery of the lesion. Histologically, these findings looked like lymph nodes in the pulmonary hilus; however, no lymph nodal structure was evident in the esophageal wall. Traction diverticula were also noted in the pigmented lesion. The patient has remained well without disease for 9 months since the surgery. Although anthracosis is a rare condition in the esophagus, the present case gave warning to pathologists and clinicians that it does indeed occur. Endoscopists and pathologists should differentiate anthracosis from malignant melanoma because the treatment and outcome are quite different for each.


Cellular & Molecular Biology Letters | 2007

High level expression of STAG1/PMEPA1 in an androgen-independent prostate cancer PC3 subclone

Yoshifumi Hirokawa; Akimitsu Takagi; Katsunori Uchida; Yuji Kozuka; Misao Yoneda; Masatoshi Watanabe; Taizo Shiraishi

In this paper, we describe the isolation and characterization of two PC3 subclones. One subclone, mr, showed an epithelial phenotype, the other, M1, showed a sarcomatous morphology. Transplanted into nude mice, mr developed tumors at a dramatically faster rate than M1. Comparing the two subclones, differentially expressed genes were identified, including E-cadherin, IL-8 and STAG1/PMEPA1. These genes were expressed at higher levels in mr than in M1.


Surgery Today | 2006

Noradrenalin-Secreting Retroperitoneal Schwannoma Resected by Hand-Assisted Laparoscopic Surgery: Report of a Case

Tomohide Hori; Kentaro Yamagiwa; Shintaro Yagi; Taku Iida; Kentaro Taniguchi; Chiduru Yamamoto; Yukitsuna Eshita; Yuji Kozuka; Haruyuki Takaki; Takuma Kato; Kanako Saito; Mie Torii; S. Isaji; Shinji Uemoto

A 66-year-old woman was admitted to our hospital for investigation of a retroperitoneal mass. She was asymptomatic but her serum noradrenalin and vanillylmandellic acid levels were increased remarkably. Computed tomographic angiography showed a mass in the left side of the superior mesenteric artery (SMA) divergence, 6 × 4 cm in size, supplied mainly by the left adrenal artery. We performed hand-assisted laparoscopic surgery (HALS) using a Cavitron ultrasonic surgical aspirator. Abdominal exploration revealed that the tumor was located in the left side of the SMA root, but was not adhered to the adjacent organs. Her vital signs remained stable during the operation. Microscopic examination revealed a palisade formation, confirming a histopathological diagnosis of degenerated schwannoma (Antoni type B). Immunohistologically, the tumor cells were stained with S-100 protein and neuron-specific enolase. Her noradrenalin level normalized immediately after the operation and she remains in good health 3 years 2 months later.


Breast Cancer | 2015

The Japanese Breast Cancer Society Clinical Practice Guideline for pathological diagnosis of breast cancer.

Rie Horii; Naoko Honma; Akiko Ogiya; Yuji Kozuka; Takayo Fukuda; Masayuki Yoshida; Shozo Ohsumi; Hirofumi Mukai

FNAC and CNB are recommended as diagnostic procedures for breast lesions (Grade B). For palpable breast lesions, FNAC has been in use as one of the most reliable diagnostic modalities for many decades. This technique is valuable because of its simplicity, cost-effectiveness, minimal invasiveness and low rate of complications. However, due to limitations of the diagnosis of breast lesions by FNAC, for instance, the difficulty of classifying a breast cancer into noninvasive or invasive carcinoma, its high rates of inadequacy and questionable accuracy, the role of FNAC has been debated recently [1]. In a previous review, the sensitivity of FNAC was reported to range from 65 to 98 % and its specificity from 34 to 100 % [2]. In Japan, a large-scale survey regarding the accuracy of FNAC by the Working Group of the Japanese Society of Clinical Cytology was conducted [3]. The survey showed that the cytological diagnosis had an inadequacy rate of 17.7 %, an indeterminate rate of This article is an English digested edition of the Nyugan Shinryo guideline 2013 nen ban, published by Kanehara & Co., LTD.


CytoJournal | 2017

Cytological features of adenocarcinoma admixed with small cell neuroendocrine carcinoma of the uterine cervix

Naoshi Shimojo; Yoshifumi Hirokawa; Kazuki Kanayama; Misao Yoneda; Ryotaro Hashizume; Akinobu Hayashi; Katsunori Uchida; Hiroshi Imai; Yuji Kozuka; Taizo Shiraishi

Adenocarcinoma admixed with neuroendocrine carcinoma of the uterine cervix is a rare malignancy with a poor prognosis, and few reports have described the cytological features of this carcinoma. To characterize the cytological features of this malignancy in cervical smears, we report a case of a 52-year-old Japanese woman with cervical adenocarcinoma admixed with small cell neuroendocrine carcinoma (SCNEC). Cytologically, there were two types of cells with different sizes. The smaller cells formed clusters, which showed a partially Indian file pattern, a high nuclear/cytoplasmic ratio, and hyperchromatic nuclei. In contrast, the larger cells showed cytological features of adenocarcinoma, indicating a glandular-like pattern. Histological examination of biopsy specimens revealed that the tumors were composed of almost equal areas of SCNEC and adenocarcinoma. Neuroendocrine differentiation was confirmed by immunohistochemistry for synaptophysin and CD56. Thus, when adenocarcinoma cells are detected in smears, attempts to search for SCNEC cells should be made by combined cytological and histological analyses in order to reach an accurate diagnosis of the carcinoma in the uterine cervix.


Breast Cancer | 2016

The Japanese Breast Cancer Society clinical practice guidelines for pathological diagnosis of breast cancer, 2015 edition

Rie Horii; Naoko Honma; Akiko Ogiya; Yuji Kozuka; Kazuya Yoshida; Masayuki Yoshida; Shinichiro Horiguchi; Yoshinori Ito; Hirofumi Mukai

The Japanese Breast Cancer Society (JBCS) Clinical Practice Guidelines were published in Japanese by Kanehara & Co., Ltd in July 2015. This article is an English digest of the guidelines for pathological diagnosis. These guidelines are updated every 2 years. In the 2015 edition, clinical questions regarding Ki67 and cell blocks were newly incorporated. All other content was reviewed and amended based on the current literature. Guidelines for pathological diagnosis


Medical Microbiology and Immunology | 2000

Incomplete replication of human parainfluenza virus type 4 in LLC-MK2 cells and in L929 cells

Hiroshi Komada; Hisae Inoue; Chihiro Yamabayashi; Morihiro Ito; Mitsuo Kawano; Machiko Nishio; Masato Tsurudome; Yuji Kozuka; Naoya Noda; Kazuyoshi Namba; Myles O'Brien; Yasuhiko Ito

Abstract Human parainfluenza virus type 4A (hPIV-4A) and type 4B (hPIV-4B) were tested for their ability to replicate in the monkey kidney LLC-MK2 cell line (MK2 cells) and the murine L929 cell line (L929 cells). These cells are normally non-permissive for replication of hPIV-4; however, treatment with acetylated trypsin led to virus replication in MK2 cells, but was less effective for L929 cells. Endogenously produced interferon (IFN) played no role in virus replication in L929 cells. Synthesis of virus-specific polypeptides was suppressed in L929 cells. WhereasNP-mRNA and HN-mRNA were detected in MK2 cells, no HN-mRNA was detected in L929 cells. These results indicate that hPIV-4 can infect both MK2 cells and L929 cells. In MK2 cells, when protease exists in the extracellular medium, hPIV-4 exhibits multistep growth. In L929 cells, however, the cause of incomplete replication might be lack of other unknown factors.


Virology | 2001

Recovery of Infectious Human Parainfluenza Type 2 Virus from cDNA Clones and Properties of the Defective Virus without V-Specific Cysteine-Rich Domain

Mitsuo Kawano; Masahiko Kaito; Yuji Kozuka; Hiroshi Komada; Naoya Noda; Kazuyoshi Nanba; Masato Tsurudome; Morihiro Ito; Machiko Nishio; Yasuhiko Ito

Collaboration


Dive into the Yuji Kozuka's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Hiroshi Komada

Suzuka University of Medical Science

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge