Department of Surgery

Welcome to the Department of Surgery (2)
We are Specialists in Cardiovascular,
Breast/Endocrine, and Thoracic Surgery.

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This department has seen not only daily medical practice but also various clinical and basic studies relating to medical practice by virtue of being within a university hospital that is also a research institution with academic publications in the respective fields and considerable achievements made to date. We also actively engage with other on- and off-campus departments and facilities.

Lead researcher: Yuko Wada

Research topic: “Research and development of novel site-selective ischemic disease therapeutic using recombinant bifidobacteria”

A new drug using a recombinant bifidobacteria preparation for expressing and secreting angiogenic factors has been created and developed. This product is an angiogenic therapeutic that is directed to ischemic disease such as chronic lower limb ischemia and myocardial infarction; by simple intravenous injection, the drug itself seeks out the ischemic site regardless of whether it is in the lower limbs, the heart, or elsewhere. Upon arrival, it acts locally and then disappears spontaneously as the patient heals. Because its administration is minimally invasive, the drug can be administered even to patients with poor general condition, such as those with diabetes, those on dialysis, and the elderly. This drug has received support from the research results optimum deployment support program, and we aim to commercialize it.

Lead researcher: Masayuki Toishi

Research topic: “Investigating the efficacy of a vessel sealing device (VSD) in thoracoscopic lung lobectomy”

Thoracoscopic lung lobectomies require surgeon skill and experience in lymph node dissection and vascular treatments involving ligation procedures. Vessel sealing devices (VSDs), which are already in use in vascular treatments in numerous fields and enhance safety, might also be exceptionally useful for lymph node dissection and small-diameter pulmonary vascular treatments. Here we measured pulmonary artery stump collapse pressures in resected specimens and analyzed clinical data to investigate the usefulness of VSDs in thoracoscopic lung lobectomies.

Publication:Usefulness of vessel-sealing devices for ≤7 mm diameter vessels: a randomized controlled trial for human thoracoscopic lobectomy in primary lung cancer.Interact Cardiovasc Thorac Surg;2014

Lead researcher: Akira Hyogotani

Research topic: “Expression of YB-1 in lung cancer and its relevance to prognosis”

YB-1 is a protein that is said to be involved in the resistance to anticancer drugs and prognosis. Immunostaining, western blotting, and other techniques were used to examine the relationship between lung cancer prognosis and YB-1 expression. Examining the relationship between YB-1 and the other proteins implicated in resistance to anticancer drugs and prognosis allows for analysis of the mechanism by which YB-1 expression is involved in lung cancer prognosis.


Publication: Association of Nuclear YB-1 Localization With Lung Resistance-related Protein and Epidermal Growth Factor Receptor Expression in Lung Cancer. Clinical Lung Cancer; 2012

Lead researcher: Tokiko Ito

Research topic: “Involvement of YB-1 in resistance to anticancer drugs in breast cancer”

expressed in cases of relapse following anticancer drug therapy or cases of resistance to anticancer drugs, was researched in a study that reported the presence of a binding protein in the Y-box promoter region called Y-box binding protein-1 (YB-1). YB-1 is said to be deeply involved in the expression of anticancer drug resistance mechanisms in cancer cells; thus, it is studied in close tandem with anticancer drug resistance mechanisms in breast cancer cells.


Publication: Alteration of Y-box Binding Protein-1 Expression Modifies the Response to Endocrine Therapy in Estrogen Receptor Positive Breast Cancer. Breast Cancer Research and Treatment; 2012

Lead researcher: Nobutaka Kobayashi

Research topic: “Cancer and the cancer microenvironment approached from the relationship with hyaluronic acid sugar chain molecules”

In addition to cancer cells, cancer tissue also encompasses fibroblasts, immune cells, component cells of the blood vessels and lymph vessels, and physiologically active substances, which together form a cancer microenvironment. Hyaluronic acid contributes to the formation of the cancer microenvironment as a major constituent sugar chain component of the extracellular matrix, and it is known to be a factor of poor prognosis in breast, ovarian, prostate, and other cancers. We conducted analyses using breast cancer tumor-bearing mice that overexpress hyaluronic acid to better understand how the hyaluronic acid extracellular matrix promotes intratumoral blood vessel development.


Publication: Hyaluronan deficiency in tumor stroma impairs macrophage trafficking and tumor neovascularization. Cancer Research; 2010

Lead researcher: Takashi Eguchi

Research topic: “Study on the impact of one-lung ventilation in neutrophil recruitment and the effects of neutrophil elastase inhibitors”


Intraoperative one-lung ventilation has been implicated as a cause of postoperative acute lung injury in the field of thoracic surgery. This study uses a rat model of one-lung ventilation to examine how one-lung ventilation impacts sequestration/migration and morphological changes in neutrophils. We also examined whether neutrophil elastase inhibitor, sivelestat, which is agent for the treatment of acute lung injury, might suppress neutrophil activation following one-lung ventilation and prevent postoperative acute lung injury. The effects of one-lung ventilation in actual lung resection were also investigated.


Publications: Lung Re-expansion following One-Lung Ventilation Induces Neutrophil Cytoskeletal Rearrangements in Rats. Annals of Thoracic and Cardiovascular Surgery; 2013

  1. Sivelestat Prevents Cytoskeletal Rearrangements in Neutrophils Resulting from Lung Re-expansion following One-Lung Ventilation during Thoracic Surgery. Inflammation;2014


Lead researcher: Takashi Eguchi

Research topic: “Usefulness of FDG-PET scans in thymic epithelial tumors”

Thymic epithelial tumors (thymoma and thymic carcinoma) have histological classifications that are reflective of their prognosis. These classifications were established from the pathological findings of a surgically excised tumor. In this study, FDG-PET scans were performed to examine whether preoperative prediction of the histological classification of thymic epithelial tumors is possible.


Publication: Utility of 18F-fluorodeoxyglucose positron emission tomography for distinguishing between the histological types of early stage thymic epithelial tumours. European Journal of Cardio-Thoracic Surgery; 2012


Lead researcher: Takashi Eguchi

Research topic: “Study on ground-glass nodules”

The growing popularity of CT has increased the number of opportunities to discover small-sized ground-glass nodules. Many of these are precancerous lesions or early lung cancer, but their growth is generally slow and much remains unknown about their natural progression and therapeutic indications. Shinshu University was an early adopter of lung cancer CT screening, and it has collected results from numerous cases of ground-glass nodules that were subject to long-term observation as well as the abundant surgical experiences from such cases. We retrospectively or prospectively studied these cases to elucidate the natural progression and therapeutic timing and content for ground-glass nodules.


Presentation: 1)Computed tomography attenuation predicts the growth of pure ground-glass nodules.Lung Cancer;2014
2)Tumor size and computed tomography attenuation of pulmonary pure ground-glass nodules are useful for predicting pathological invasiveness.PLoS One;2014


Lead researcher: Takashi Eguchi

Research topic: “Lung segmentectomy using 3D-CT”

The increase in cases of early lung cancer has led to increased opportunities for reduced surgery. Lung segmentectomy, a form of reduced surgery, is an especially difficult operation due to the need to address variations in the pulmonary vessels and bronchi.

Our facility constructs 3D images of the pulmonary vessels and bronchi using contrast CT prior to surgery and performs careful preoperative simulations. Operating while checking the 3D images using an iPad during surgery has made it possible to safely and reliably implement lung segmentectomy.

YB-1 YB-1

Publication: Three-dimensional imaging navigation during a lung segmentectomy using an iPad. European Journal of Cardio-Thoracic Surgery; 2012

Lead researcher: Takayuki Watanabe

Research topic: “Analysis of anticancer drug sensitivity in tamoxifen-resistant breast cancer”

In estrogen receptor (ER)-positive recurrent breast cancer, chemotherapy is selected if life-threatening metastasis is observed or if it becomes resistant to endocrine therapy, but useful indicators for the selection of chemotherapeutic agents have yet to be established. To identify these indicators, we confirmed differences in anticancer drug sensitivity using ER-positive breast cancer cell lines and coordinating tamoxifen-resistant strains.

Lead Researcher: Toru Hanamura

Research topic: “Analysis of aromatase inhibitor resistance mechanisms in breast cancer cell lines”

In recent years, the use of chemotherapy or endocrine therapy after surgery for breast cancer treatment has been shown to lower a patient’s risk of relapse, and aromatase inhibitors have been used as adjuvant endocrine therapy for many patients, especially those with postmenopausal hormone-sensitive breast cancer. By clarifying the mechanisms of drug resistance against these aromatase inhibitors, our laboratory aims to develop new therapeutic drugs and minimize breast cancer relapse rates by individualizing treatments.


Publication: Androgen metabolite-dependent growth of hormone receptor-positive breast cancer as a possible aromatase inhibitor-resistance mechanism. Breast Cancer Research and Treatment; 2013

Lead researcher: Toshihiro Okada

Topic: “Identifying cancer stem cells in thyroid cancer”

In thyroid cancer, undifferentiated cancer follows a course with an especially poor prognosis among malignant tumors compared with those of differentiated cancers, which have a better prognosis (e.g., papillary carcinoma, follicular carcinoma), and the mechanism of anaplastic conversion remains unclear. Considering the features of undifferentiated cancer, which is resistant to chemotherapy and radiotherapy, it is presumably also possible that cancer stem cells that are present within differentiated cancer are involved in the anaplastic conversion.


This study aims to analyze the features of undifferentiated cancer from the perspective of cancer stem cells and uses thyroid cancer cell lines and thyroid cancer clinical specimens in fluorescence activated cell sorting analysis, immunostaining, and so forth to facilitate analysis of the factors associated with cancer stem cells in thyroid cancer.


Presentation: Coexpression of EpCAM, CD44 variant isoforms and claudin-7 in anaplastic thyroid carcinoma. PLoS One;2014