Yukiko Niwa
   Department   School of Medicine(Yachiyo Medical Center), School of Medicine
   Position   Assistant Professor
Article types Original article
Language English
Peer review Peer reviewed
Title Downregulation of GPR155 as a prognostic factor after curative resection of hepatocellular carcinoma.
Journal Formal name:BMC cancer
Abbreviation:BMC Cancer
ISSN code:14712407/14712407
Domestic / ForeginForegin
Volume, Issue, Page 17(1),pp.610
Author and coauthor Umeda Shinichi, Kanda Mitsuro, Sugimoto Hiroyuki, Tanaka Haruyoshi, Hayashi Masamichi, Yamada Suguru, Fujii Tsutomu, Takami Hideki, Niwa Yukiko, Iwata Naoki, Tanaka Chie, Kobayashi Daisuke, Fujiwara Michitaka, Kodera Yasuhiro
Publication date 2017/09
Summary BACKGROUND:Molecular biomarkers capable of predicting recurrence patterns and prognosis are helpful for risk stratification and providing appropriate treatment to patients with hepatocellular carcinoma (HCC). In this study, we focused on G protein-coupled receptor 155 (GPR155), a cell surface signaling protein, as a candidate biomarker.METHODS:We analyzed GPR155 expression, DNA methylation, and copy number in HCC cell lines. The clinical significance of GPR155 expression was evaluated using 144 pairs of surgically resected liver and normal tissues with subgroup analysis based on hepatitis virus infection.RESULTS:GPR155 mRNA expression levels were differential and were decreased in 89% of HCC cell lines. No DNA methylation was detected, whereas copy number alterations were present in five (56%) HCC cell lines. GPR155 mRNA expression level was independent of background liver status and significantly lower in HCC tissues than corresponding normal liver tissues. The expression patterns of GPR155 protein by immunohistochemical staining were significantly associated with those of GPR155 mRNA. Downregulation of GPR155 was significantly associated with more aggressive HCC phenotypes including high preoperative α-fetoprotein, poor differentiation, serosal infiltration, vascular invasion, and advanced disease stage. Patients with downregulation of GPR155 were more likely to have worse prognosis after curative resection irrespective of hepatitis virus infection. Patients who experienced extrahepatic (distant) recurrences had significantly lower GPR155 expression than those with intrahepatic (liver confined) recurrences.CONCLUSIONS:Downregulation of GPR155 may serve as a prognosticator that also predicts initial recurrence sites independent of hepatitis virus infection.
DOI 10.1186/s12885-017-3629-2
PMID 28863781