Genomic and transcriptomic landscape of carcinogenesis in patients with gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS)

C Chihiro Matsumoto (Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University) K Kazuki K. Takahashi (Laboratory of Molecular Medicine, Human Genome Center, The Institute of Medical Science, The University of Tokyo) M Masaaki Iwatsuki (Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University) N Noriko Yasuda-Yoshihara (Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University) A Atsushi Niida (Laboratory of Molecular Medicine, Human Genome Center, The Institute of Medical Science, The University of Tokyo) K Kohei Yamashita (Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University) T Takeshi Morinaga (Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University) K Kojiro Eto (Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University) S Shiro Iwagami (Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University) S Satoshi Ida (Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University) H Hiromu Yano (Department of Cell Pathology, Graduate School of Medical Sciences, Kumamoto University) Y Yoshihiro Komohara (Department of Cell Pathology, Graduate School of Medical Sciences, Kumamoto University) Y Yuji Miyamoto (Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University) T Takaaki Masuda (Department of Breast and Endocrine Surgery, Kochi University) Y Yasuhito Tanaka (Department of Gastroenterology and Hepatology, Faculty of Life Sciences, Kumamoto University) K Koshi Mimori (Department of Surgery, Kyushu University Beppu Hospital) H Hideo Baba (Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University)

Abstract

Gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS) is an autosomal dominant syndrome characterized by polyposis localized in the gastric body and fundus with a strong tendency for adenocarcinoma. The genetic mutations that accumulate during the progression from normal mucosa through polyp to carcinoma in GAPPS remain unclear. We investigated the evolutionary process from normal mucosa to polyp and carcinoma in GAPPS. Through comprehensive mutational and transcriptome analyses, we aimed to provide insights into the biology of this disease. Whole-exome sequencing and RNA sequencing were performed on carcinoma, polyp, and normal mucosa samples from multiple sites from seven patients with GAPPS (n = 54 samples). We comprehensively investigated genomic alterations (including copy number alterations and somatic mutations), clonal architecture, and transcriptome dynamics during carcinogenesis. Genomic evolutionary analysis showed that in GAPPS, somatic mutations of APC occur in carcinoma and polyp while mutations of KRAS additionally occur in carcinoma. We also found the co-occurrence of APC and KRAS mutations in carcinoma recurrently both across cases and within subclones of the same case. The co-occurrence of APC/KRAS mutations may contribute to the carcinogenesis of GAPPS. Our study provides detailed information on the genomic and transcriptomic landscape in GAPPS carcinogenesis, conferring valuable insights into its underlying mechanisms.

Article Details

Volume / Issue Vol. 122, Issue 44
Published November 04, 2025
ISSN 0027-8424
Publisher National Academy of Sciences

Authors (17)

C

Chihiro Matsumoto

Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University

K

Kazuki K. Takahashi

Laboratory of Molecular Medicine, Human Genome Center, The Institute of Medical Science, The University of Tokyo

M

Masaaki Iwatsuki

Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University

N

Noriko Yasuda-Yoshihara

Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University

A

Atsushi Niida

Laboratory of Molecular Medicine, Human Genome Center, The Institute of Medical Science, The University of Tokyo

K

Kohei Yamashita

Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University

T

Takeshi Morinaga

Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University

K

Kojiro Eto

Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University

S

Shiro Iwagami

Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University

S

Satoshi Ida

Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University

H

Hiromu Yano

Department of Cell Pathology, Graduate School of Medical Sciences, Kumamoto University

Y

Yoshihiro Komohara

Department of Cell Pathology, Graduate School of Medical Sciences, Kumamoto University

Y

Yuji Miyamoto

Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University

T

Takaaki Masuda

Department of Breast and Endocrine Surgery, Kochi University

Y

Yasuhito Tanaka

Department of Gastroenterology and Hepatology, Faculty of Life Sciences, Kumamoto University

K

Koshi Mimori

Department of Surgery, Kyushu University Beppu Hospital

H

Hideo Baba

Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University