title: Prognostic and clinical impact of PIK3CA mutation in gastric cancer: pyrosequencing technology and literature review.
abstract: Phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA) mutations that activate the PI3K/AKT signaling pathway have been observed in several types of carcinoma and have been associated with patient prognosis. However, the significance of PIK3CA mutations in gastric cancer remains unclear. This retrospective study investigated the relationship between PIK3CA mutations and clinical outcomes in patients with gastric cancer. Additionally, we reviewed the rate of PIK3CA mutations in gastric cancer and the association between PIK3CA mutations and prognosis in human cancers.
  
  
  
  The study included 208 patients with gastric cancer who underwent surgical resection at Kumamoto University Hospital, Japan, between January 2001 and August 2010. Mutations in PIK3CA exons 9 and 20 were quantified by pyrosequencing assays.
  
  
  
  PIK3CA mutations were detected in 25 (12 %) of the 208 patients. Ten patients had c.1634A > G (p.E545G), 10 had c.1624G > A (p.E542K), 13 had c.1633G > A (p.E545K), nine had c.3139C > T (p.H1047R), and 1 had c.3140A > G (p.H1047Y) mutations. PIK3CA mutations were not significantly associated with any clinical, epidemiologic, or pathologic characteristic. Kaplan-Meier analysis showed no significant differences in disease-free survival (log rank P = 0.84) and overall survival (log rank P = 0.74) between patients with and without PIK3CA mutations.
  
  
  
  Mutations in PIK3CA did not correlate with prognosis in patients with gastric cancer, providing additional evidence for the lack of relationship between the two.
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Science, Kumamoto University, 1-1-1 Honjo, Kumamoto, 860-8556, Japan.
authors.forename: Kazuto
authors.initials: K
authors.lastname: Harada
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Science, Kumamoto University, 1-1-1 Honjo, Kumamoto, 860-8556, Japan.
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Baba
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Science, Kumamoto University, 1-1-1 Honjo, Kumamoto, 860-8556, Japan.
authors.forename: Hironobu
authors.initials: H
authors.lastname: Shigaki
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Science, Kumamoto University, 1-1-1 Honjo, Kumamoto, 860-8556, Japan.
authors.forename: Takatsugu
authors.initials: T
authors.lastname: Ishimoto
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Science, Kumamoto University, 1-1-1 Honjo, Kumamoto, 860-8556, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Miyake
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Science, Kumamoto University, 1-1-1 Honjo, Kumamoto, 860-8556, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Kosumi
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Science, Kumamoto University, 1-1-1 Honjo, Kumamoto, 860-8556, Japan.
authors.forename: Ryuma
authors.initials: R
authors.lastname: Tokunaga
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Science, Kumamoto University, 1-1-1 Honjo, Kumamoto, 860-8556, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Izumi
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Science, Kumamoto University, 1-1-1 Honjo, Kumamoto, 860-8556, Japan.
authors.forename: Mayuko
authors.initials: M
authors.lastname: Ohuchi
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Science, Kumamoto University, 1-1-1 Honjo, Kumamoto, 860-8556, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Nakamura
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Science, Kumamoto University, 1-1-1 Honjo, Kumamoto, 860-8556, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Kiyozumi
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Science, Kumamoto University, 1-1-1 Honjo, Kumamoto, 860-8556, Japan.
authors.forename: Junji
authors.initials: J
authors.lastname: Kurashige
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Science, Kumamoto University, 1-1-1 Honjo, Kumamoto, 860-8556, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Iwatsuki
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Science, Kumamoto University, 1-1-1 Honjo, Kumamoto, 860-8556, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Miyamoto
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Science, Kumamoto University, 1-1-1 Honjo, Kumamoto, 860-8556, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Sakamoto
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Science, Kumamoto University, 1-1-1 Honjo, Kumamoto, 860-8556, Japan.
authors.forename: Naoya
authors.initials: N
authors.lastname: Yoshida
authors.affiliation: Department of Gastroenterological Surgery, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Watanabe
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medical Science, Kumamoto University, 1-1-1 Honjo, Kumamoto, 860-8556, Japan. hdobaba@kumamoto-u.ac.jp.
authors.forename: Hideo
authors.initials: H
authors.lastname: Baba
mesh_terms: D000368:Aged; D058534:Class I Phosphatidylinositol 3-Kinases / Q000235:genetics*; D005091:Exons; D005260:Female; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D059014:High-Throughput Nucleotide Sequencing / Q000379:methods*; D006801:Humans; D008297:Male; D020641:Polymorphism, Single Nucleotide; D011379:Prognosis; D012189:Retrospective Studies; D017422:Sequence Analysis, DNA; D013274:Stomach Neoplasms / Q000235:genetics*; D016019:Survival Analysis
chemical_list: D058534:Class I Phosphatidylinositol 3-Kinases; C484760:PIK3CA protein, human
keywords: Gastric cancer; PIK3CA mutation; Prognosis; Pyrosequencing