title: Prognostic relevance ofSAMSN1expression in gastric cancer.
abstract: The prognosis for patients with advanced gastric cancer (GC) remains poor. The identification of biomarkers relevant to the recurrence and metastasis of GC is advantageous for stratifying patients and proposing novel molecular targets. In the present study the oncological roles of SAM domain, SH3 domain and nuclear localization signals 1 (SAMSN1), a mediator of B-cell function, were elucidated in GC. The expression and methylation status ofSAMSN1were investigated in a panel of 11 GC cell lines. Immunohistochemical staining was performed to determine the pattern of SAMSN1 protein expression in gastric tissues. The prognostic impact ofSAMSN1expression was determined by analyzing 175 pairs of surgically resected gastric tissues. A marked decrease in the level ofSAMSN1mRNA was detected in 8/11 GC cell lines as compared with that in a non-transformed intestinal epithelium cell line (FHs 74) without promoter methylation. The mean expression level ofSAMSN1mRNA was reduced in GC tissues compared with normal adjacent tissues, an observation that was independent of tumor differentiation. The pattern of SAMSN1 protein expression was significantly correlated with that ofSAMSN1mRNA. LowSAMSN1mRNA expression was significantly associated with tumor size (>60 mm; P=0.026) and shorter overall survival times (P=0.004). Multivariate analysis identified lowSAMSN1mRNA expression as an independent prognostic factor for poor overall survival (hazard ratio, 1.80; 95% confidence interval, 1.07-3.05; P=0.025). The difference in survival between the low and highSAMSN1expression groups was more marked in patients with stage II/III GC compared to those with stage IV GC. In patients with stage II/III GC who underwent curative surgery, lowSAMSN1expression was associated with reduced disease free survival times. The results of the present study indicate that downregulation ofSAMSN1transcription may affect the progression and recurrence of GC, and therefore may represent a novel biomarker of GC.
authors.affiliation: Department of Gastroenterological Surgery (Surgery II), Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan.
authors.forename: Mitsuro
authors.initials: M
authors.lastname: Kanda
authors.affiliation: Department of Gastroenterological Surgery (Surgery II), Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan.
authors.forename: Dai
authors.initials: D
authors.lastname: Shimizu
authors.affiliation: Department of Gastroenterological Surgery (Surgery II), Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Sueoka
authors.affiliation: Department of Surgery, Aichi-Gakuin University School of Dentistry, Nagoya, Aichi 464-8651, Japan.
authors.forename: Shuji
authors.initials: S
authors.lastname: Nomoto
authors.affiliation: Department of Gastroenterological Surgery (Surgery II), Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan.
authors.forename: Hisaharu
authors.initials: H
authors.lastname: Oya
authors.affiliation: Department of Gastroenterological Surgery (Surgery II), Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Takami
authors.affiliation: Department of Gastroenterological Surgery (Surgery II), Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Ezaka
authors.affiliation: Department of Gastroenterological Surgery (Surgery II), Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan.
authors.forename: Ryoji
authors.initials: R
authors.lastname: Hashimoto
authors.affiliation: Department of Gastroenterological Surgery (Surgery II), Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Tanaka
authors.affiliation: Department of Gastroenterological Surgery (Surgery II), Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kobayashi
authors.affiliation: Department of Gastroenterological Surgery (Surgery II), Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan.
authors.forename: Chie
authors.initials: C
authors.lastname: Tanaka
authors.affiliation: Department of Gastroenterological Surgery (Surgery II), Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan.
authors.forename: Suguru
authors.initials: S
authors.lastname: Yamada
authors.affiliation: Department of Gastroenterological Surgery (Surgery II), Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Fujii
authors.affiliation: Department of Gastroenterological Surgery (Surgery II), Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan.
authors.forename: Goro
authors.initials: G
authors.lastname: Nakayama
authors.affiliation: Department of Gastroenterological Surgery (Surgery II), Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Sugimoto
authors.affiliation: Department of Gastroenterological Surgery (Surgery II), Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Koike
authors.affiliation: Department of Gastroenterological Surgery (Surgery II), Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan.
authors.forename: Michitaka
authors.initials: M
authors.lastname: Fujiwara
authors.affiliation: Department of Gastroenterological Surgery (Surgery II), Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kodera
keywords: SAM domain; SH3 domain and nuclear localization signals 1; expression; gastric cancer; prognosis