Trophoblast Cell Surface Antigen 2 Expression in Thymic Carcinoma: Brief Report

Kana Kurokawa, MD, PhD; Tetsuhiko Asao, MD, PhD; Takuo Hayashi, MD, PhD; Satsuki Kishikawa, MD, PhD; Koichiro Kanamori, MD, PhD; Takehito Shukuya, MD, PhD; Yosuke Miyashita, MD; Ikuko Nakamura, MD, PhD; Taichi Miyawaki, MD, PhD; Ryota Kanemaru, MD, PhD; Tomoyasu Mimori, MD, PhD; Yoichiro Mitsuishi, MD, PhD; Ken Tajima, MD, PhD; Naoko Shimada, MD, PhD; Fumiyuki Takahashi, MD, PhD; Kazuya Takamochi, MD, PhD; Kenji Suzuki, MD, PhD; Kazuhisa Takahashi, MD, PhD

JTO Clinical and Research Reports (Jul 2024)

Trophoblast Cell Surface Antigen 2 Expression in Thymic Carcinoma: Brief Report

Kana Kurokawa, MD, PhD,
Tetsuhiko Asao, MD, PhD,
Takuo Hayashi, MD, PhD,
Satsuki Kishikawa, MD, PhD,
Koichiro Kanamori, MD, PhD,
Takehito Shukuya, MD, PhD,
Yosuke Miyashita, MD,
Ikuko Nakamura, MD, PhD,
Taichi Miyawaki, MD, PhD,
Ryota Kanemaru, MD, PhD,
Tomoyasu Mimori, MD, PhD,
Yoichiro Mitsuishi, MD, PhD,
Ken Tajima, MD, PhD,
Naoko Shimada, MD, PhD,
Fumiyuki Takahashi, MD, PhD,
Kazuya Takamochi, MD, PhD,
Kenji Suzuki, MD, PhD,
Kazuhisa Takahashi, MD, PhD

Affiliations

Kana Kurokawa, MD, PhD: Department of Respiratory Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan
Tetsuhiko Asao, MD, PhD: Department of Respiratory Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan; Corresponding author. Address for correspondence: Tetsuhiko Asao, MD, PhD, Department of Respiratory Medicine, Juntendo University Graduate School of Medicine, 3-1-3 Hongo, Bunkyo-ku, Tokyo 113-8431, Japan.
Takuo Hayashi, MD, PhD: Department of Human Pathology, Juntendo University Graduate School of Medicine, Tokyo, Japan
Satsuki Kishikawa, MD, PhD: Department of Human Pathology, Juntendo University Graduate School of Medicine, Tokyo, Japan
Koichiro Kanamori, MD, PhD: Department of Respiratory Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan
Takehito Shukuya, MD, PhD: Department of Respiratory Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan
Yosuke Miyashita, MD: Department of Respiratory Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan
Ikuko Nakamura, MD, PhD: Department of Respiratory Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan
Taichi Miyawaki, MD, PhD: Department of Respiratory Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan
Ryota Kanemaru, MD, PhD: Department of Respiratory Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan
Tomoyasu Mimori, MD, PhD: Department of Respiratory Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan
Yoichiro Mitsuishi, MD, PhD: Department of Respiratory Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan
Ken Tajima, MD, PhD: Department of Respiratory Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan
Naoko Shimada, MD, PhD: Department of Respiratory Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan
Fumiyuki Takahashi, MD, PhD: Department of Respiratory Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan
Kazuya Takamochi, MD, PhD: Department of General Thoracic Surgery, Juntendo University Graduate School of Medicine, Tokyo, Japan
Kenji Suzuki, MD, PhD: Department of General Thoracic Surgery, Juntendo University Graduate School of Medicine, Tokyo, Japan
Kazuhisa Takahashi, MD, PhD: Department of Respiratory Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan

Journal volume & issue: Vol. 5, no. 7
p. 100693

Abstract

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Introduction: Trophoblast cell surface antigen 2 (TROP2) is a transmembrane glycoprotein overexpressed in various cancer types. Although TROP2-targeting therapy is currently attracting attention, little is known about TROP2 expression in thymic carcinoma. Methods: TROP2 gene expression in thymic epithelial tumors was analyzed using RNA-sequencing (RNA-seq) data for 122 cases obtained from The Cancer Genome Atlas. Immunohistochemistry (IHC) staining with anti-TROP2 antibody (SP295) was performed in 26 cases of thymic carcinoma tissues surgically resected at Juntendo University. Results: RNA-seq data analysis from The Cancer Genome Atlas revealed that TACSTD2 (gene encoding TROP2) expression was significantly higher in thymic carcinoma than in thymoma (adjusted p = 6.64e-05). There was also a trend of increasing expression in the order of thymoma type B1, B2, B3, and thymic carcinoma. As for IHC in thymic carcinoma, TROP2 expression was localized to the membrane of cancer cells. Intensity 0, 1, and 2 was observed in six (23.1%), 11 (42.3%), and nine (34.6%) cases, respectively, leading to TROP2 positivity in 20 cases (76.9%). The median proportion of TROP2-positive tumor cells and the median H-score were 25.0% (range: 0%–100%) and 25.0 (range: 0–200), respectively. No relevant factors were identified in the analysis of TROP2 expression and patient background. Although not significant, high TROP2 expression (H-score ≥ 50) tended to be associated with shorter survival. Conclusions: TROP2 expression in thymic carcinoma was confirmed by both RNA-seq and IHC, with high expression observed in IHC for intensity (76.9%) and proportion. TROP2 could be a potential target in thymic carcinoma.

Published in JTO Clinical and Research Reports

ISSN: 2666-3643 (Online)
Publisher: Elsevier
Country of publisher: United States
LCC subjects: Medicine: Internal medicine: Neoplasms. Tumors. Oncology. Including cancer and carcinogens
Website: https://www.journals.elsevier.com/jto-clinical-and-research-reports/

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