博士（医学）, 信州大学

Tumor biology

Prognostic significance of baseline skeletal muscle index and its dynamics in patients with metastatic breast cancer undergoing eribulin treatment
Masatsugu Amitani; Takaaki Oba; Ayaka Kitazawa; Ryoko Iji; Nami Kiyosawa; Shota Katsuyama; Hiroki Morikawa; Tatsunori Chino; Tadafumi Shimizu; Mayu Ono; Toshiharu Kanai; Ken-ichi Ito
Breast Cancer Research and Treatment, 214(3), 419-429, Oct. 2025
Corresponding

Activation of the AKT-mTOR pathway confers selpercatinib resistance in thyroid cancer cells harboring the CCDC6-RET fusion gene
Masatsugu Amitani; Tadafumi Shimizu; Takaaki Oba; Masaki Kawamura; Ken-ichi Ito
Biochemistry and Biophysics Reports, 43, 102136-102136, Sep. 2025

Impact of Glucocorticoids on Immune Checkpoint Inhibitor Efficacy and Circulating Biomarkers in Non–Small Cell Lung Cancer Patients
Lauren Polyakov; Angelina Lim; Alexandra Meyer; Aubree Mades; Joshua Ni; Ryan Cooper; Shirley Ye; Ryutaro Kajihara; Takaaki Oba; Leslie Contreras; Eihab Abdelfatah; Joy Sarkar; Junko Matsuzaki; Ming Li; Rajeev Sharma; Brahm H. Segal; Robert C. Hsu; Hongbin Chen; Jorge Nieva; Fumito Ito
Cancer Research Communications, 5(7), 1082-1094, Jul. 2025

Validation of the predictive ability for recurrence and the clinical utility of the 95-gene classifier (95GC) through an integrated analysis of five studies
Aya Imai; Ryo Tsunashima; Yu Hidaka; Sae Kitano; Chikage Kato; Akira Watanabe; Midori Morita; Koichi Sakaguchi; Yoshiaki Sota; Masahiko Suzuki; Takayuki Kinoshita; Seiichi Imanishi; Masahiro Oikawa; Yoshihiko Kamada; Ken-ichi Ito; Takaaki Oba; Shin Takayama; Fumine Tsukamoto; Mina Takahashi; Yutaka Hatanaka; Naoto T. Ueno; Kenzo Shimazu; Satoshi Morita; Yasuto Naoi
Breast Cancer, 32(5), 1075-1087, Jun. 2025

Utility of contrast-enhanced magnetic resonance imaging for planning of surgical procedure in Paget's disease of the breast.
Oba T, Maeno K, Iji R, Kiyosawa N, Park Y, Morikawa H, Amitani M, Shimizu T, Ono M, Ito T, Kanai T, Matoba H, Takayama F, Ito KI.
Surg Today., 55(6), 778-786, 2024

Clinical and immunological relevance of SLAMF6 expression in the tumor microenvironment of breast cancer and melanoma.
Oba T, Long M, Ito KI, Ito F.
Sci Rep, 14(1), 2394, 2024
Lead

MEN1に伴う原発性副甲状腺機能亢進症術後の長期成績
大場崇旦、井地瞭子、清沢奈美、網谷正統、清水忠史、小野真由、金井敏晴、伊藤研一
日本内分泌外科学会雑誌, 40(4), 241-245, 2023

Eribulin promotes proliferation of CD8+ T cells and potentiates T cell-mediated anti-tumor activity against triple-negative breast cancer cells.
Shimizu T, Oba T, Oshi M, Ito KI.
Breast Cancer Res Treat., 2023

The Japanese Breast Cancer Society Clinical Practice Guidelines for systemic treatment of breast cancer, 2022 edition.
Terada M, Ito A, Kikawa Y, Koizumi K, Naito Y, Shimoi T, Ishihara M, Yamanaka T, Ozaki Y, Hara F, Nakamura R, Hattori M, Miyashita M, Kondo N, Yoshinami T, Takada M, Matsumoto K, Narui K, Sasada S, Iwamoto T, Hosoda M, Takano Y, Oba T, Sakai H, Murakami A, Higuchi T, Tsuchida J, Tanabe Y, Shigechi T, Tokuda E, Harao M, Kashiwagi S, Mase J, Watanabe J, Nagai SE, Yamauchi C, Yamamoto Y, Iwata H, Saji S, Toyama T.
Breast Cancer, 2023

Development of a predictive score for post-hemithyroidectomy hypothyroidism using skeletal muscle index, remnant thyroid index, and thyroid-stimulating hormone levels: a retrospective cohort study.
Amitani M, Oba T, Kiyosawa N, Iji R, Morikawa H, Chino T, Shimizu T, Ono M, Kanai T, Maeno K, Ito KI.
Quant Imaging Med Surg, 2023

Significance of skeletal muscle index-to-body mass index ratio as a predictor of postsurgical bleeding after mastectomy in patients with breast cancer.
Morikawa H, Oba T, Kiyosawa N, Iji R, Amitani M, Chino T, Shimizu T, Ono M, Kanai T, Maeno K, Ito KI.
Breast Cancer., 2023

Neutrophil-to-lymphocyte ratio is associated with the proportion of poorly differentiated components in papillarythyroid carcinoma.
Oba T, Kazuma M, Kiyosawa N, Morikawa H, Amitani M, Chino T Shimizu T, Ono M, Ito T, Kanai T, Ito KI.
J Surg Res, 287, 47-54, 2023
Lead

The Advantage of Using an Optical See-Through Head-Mounted Displayin Ultrasonography-Guided Needle Biopsy Procedures: A Prospective Randomized Study.
Shimizu T, Oba T (co-first author), Ito KI.
J Clin Med, 2023

Changes in thepathophysiology of primary hyperparathyroidism and analysis of postoperative recurrence cases at a regional corehospital in Japan: experience of 35 years in Shinshu University Hospital.
Kanai T, Oba T, Morikawa H, Amitani M, Chino T, Shimizu T, Ono MT, Maeno K, Ito KI, Ito T.
Ann Palliat Med., 2023

Predictive and Prognostic Implications of Circulating CX3CR1+ CD8+ T Cells in Non-Small Cell LungCancer Patients Treated with Chemo-Immunotherapy.
Abdelfatah E, Long MD, Kajihara R, Oba T, Yamauchi T, Chen H, Sarkar J, Attwood K, Matsuzaki J, Segal B, DyGK, Ito F.
Cancer Res Commun, 2023

Fluctuations in Gut MicrobiomeComposition During Immune Checkpoint Inhibitor Therapy.
Sarkar J, Cortes Gomez E, Oba T, Chen H, Dy GK, Segal BH, Ernstoff MS, Ito F.
World J Oncol., 2023

A Case of a Cystic Parathyroid Adenoma with Marked Hyperparathyroidism but Difficult Preoperative Diagnostic Imaging
KUBOTA Satoshi, SHIMADA Yasuho, TAKAYAMA Shohei, OBA Takaaki, ITO Ken-ichi, KOMATSU Mitsuhisa
The Shinshu Medical Journal, 70(3), 189-194, Jun. 2022

CD40 and CD80/86 signaling in cDC1s mediate effective neoantigen vaccination and generation of antigen-specific CX3CR1(+) CD8(+) T cells
Yamauchi, Takayoshi; Hoki, Toshifumi; Oba, Takaaki; Kajihara, Ryutaro; Attwood, Kristopher; Cao, Xuefang; Ito, Fumito
CANCER IMMUNOLOGY IMMUNOTHERAPY, 71(1), 137-151, Jan. 2022

がん免疫療法におけるT細胞に発現するCX3CR1の重要性
大場 崇旦; オオバ タカアキ; 伊藤 史人; イトウ フミト
臨床免疫・アレルギー科 = Clinical immunology & allergology / 臨床免疫・アレルギー科編集委員会 編, 76(5), 573-580, Nov. 2021

The mechanisms involved in the resistance of estrogen receptor-positive breast cancer cells to palbociclib are multiple and change over time
Ono, Mayu; Oba, Takaaki; Shibata, Tomohiro; Ito, Ken-Ichi
JOURNAL OF CANCER RESEARCH AND CLINICAL ONCOLOGY, 147(11), 3211-3224, Nov. 2021

In situ delivery of iPSC-derived dendritic cells with local radiotherapy generates systemic antitumor immunity and potentiates PD-L1 blockade in preclinical poorly immunogenic tumor models
Oba, Takaaki; Makino, Kenichi; Kajihara, Ryutaro; Yokoi, Toshihiro; Araki, Ryoko; Abe, Masumi; Minderman, Hans; Chang, Alfred E.; Odunsi, Kunle; Ito, Fumito
JOURNAL FOR IMMUNOTHERAPY OF CANCER, 9(5), e002432, May 2021

HDAC6 inhibition enhances the anti-tumor effect of eribulin through tubulin acetylation in triple-negative breast cancer cells
Oba T, Ono M, Matoba H, Uehara T, Hasegawa Y, Ito KI.
Breast Cancer Res Treat., 186(1), 37-51, Feb. 2021

Prognostic Nutritional Index Is Superior to Neutrophil-to-lymphocyte Ratio as a Prognostic Marker in Metastatic Breast Cancer Patients Treated With Eribulin
Oba, Takaaki; Maeno, Kazuma; Ono, Mayu; Ito, Tokiko; Kanai, Toshiharu; Ito, Ken-ichi
ANTICANCER RESEARCH, 41(1), 445-452, Jan. 2021

Fibroadenoma in a young male breast: A case report and review of the literature.
13. Morikawa H, Nobuoka M, Amitani M, Shimizu T, Ohno K, Ono M, Oba T, Ito T, Kanai T, Maeno K, Uehara T, Ito KI.
Clin Case Rep., 2021

Multicenter retrospective study on the use of Curebest (TM) 95GC Breast for estrogen receptor-positive and node-negative early breast cancer
Tsukamoto, Fumine; Arihiro, Koji; Takahashi, Mina; Ito, Ken-ichi; Ohsumi, Shozo; Takashima, Seiki; Oba, Takaaki; Yoshida, Masayuki; Kishi, Kazuki; Yamagishi, Keisuke; Kinoshita, Takayuki
BMC CANCER, 21(1), 1077, 2021

Papillary thyroid microcarcinoma with lung metastases: a case report and review of the literature.
11. Shimizu T, Oba T, Chino T, Soma A, Ono M, Ito T, Kanai T, Maeno K, Sato Y, Uehara T, Ito KI.
Thyroid Res, 2021

T-cell CX3CR1 expression as a dynamic blood-based biomarker of response to immune checkpoint inhibitors
Yamauchi, Takayoshi; Hoki, Toshifumi; Oba, Takaaki; Jain, Vaibhav; Chen, Hongbin; Attwood, Kristopher; Battaglia, Sebastiano; George, Saby; Chatta, Gurkamal; Puzanov, Igor; Morrison, Carl; Odunsi, Kunle; Segal, Brahm H.; Dy, Grace K.; Ernstoff, Marc S.; Ito, Fumito
NATURE COMMUNICATIONS, 12(1), 1402, 2021

Local, multimodal intralesional therapy renders distant brain metastases susceptible to PD-L1 blockade in a preclinical model of triple-negative breast cancer
Yokoi, Toshihiro; Oba, Takaaki; Kajihara, Ryutaro; Abrams, Scott, I; Ito, Fumito
SCIENTIFIC REPORTS, 11(1), 21992, 2021

Multimodal Intralesional Therapy for Reshaping the Myeloid Compartment of Tumors Resistant to Anti-PD-L1 Therapy via IRF8 Expression
Patel, Ankit; Oba, Takaaki; Kajihara, Ryutaro; Yokoi, Toshihiro; Abrams, Scott I.; Ito, Fumito
JOURNAL OF IMMUNOLOGY, 207(5), 1298-1309, 2021

Prognostic significance of neutrophil-to-lymphocyte ratio for long-term outcomes in patients with poorly differentiated thyroid cancer
Oba, Takaaki; Maeno, Kazuma; Amitani, Masatsugu; Shimizu, Tadafumi; Ohno, Koichi; Ono, Mayu; Ito, Tokiko; Kanai, Toshiharu; Uehara, Takeshi; Ito, Ken-Ichi
ENDOCRINE JOURNAL, 68(11), 1329-1336, 2021

Neoadjuvant In Situ Immunomodulation Enhances Systemic Antitumor Immunity against Highly Metastatic Tumors
Oba, Takaaki; Kajihara, Ryutaro; Yokoi, Toshihiro; Repasky, Elizabeth A.; Ito, Fumito
CANCER RESEARCH, 81(24), 6183-6195, 2021

Tamoxifen resistance alters sensitivity to 5-fluorouracil in a subset of estrogen receptor-positive breast cancer.
Watanabe T, Oba T, Tanimoto K, Shibata T, Kamijo S, Ito KI.
PLOS ONE, 2021