Alterations of BAT-26 identify a subset of gastric cancer with distinct clinicopathologic features and better postoperative prognosis.
OBJECTIVE
Gastrointestinal tumors with microsatellite instability represent a replication error-positive phenotype. BAT-26, a repeat of 26 deoxyadenosine localized in intron 5 of hMSH2 gene, has been reported as a reliable indicator of replication error phenotype in colorectal cancers. This study investigated whether BAT-26 is a useful marker for a mutator phenotype with distinct clinicopathologic features in gastric cancer.


METHODS
One hundred and nineteen gastric cancer tissues and matched non-tumor tissue were examined by polymerase chain reactions with electrophoresis for 9 dinucleotide microsatellites and BAT-26, and frameshift mutations of transforming growth factor-beta type II receptor. The relation between BAT-26 alterations and relevant clinicopathological or genetic parameters were analyzed.


RESULTS
Gastric cancer with BAT-26 alterations was highly correlated with multiple microsatellite alterations (> or = 3 loci) and frameshift mutations of transforming growth factor-beta type II receptor, and predominantly showed antral location, intestinal histologic subtype, advanced stage, a higher rate of Helicobacter pylori infection, a better postoperative survival and less lymph node metastasis.


CONCLUSIONS
These results show testing of BAT-26 alterations is a convenient and rapid screening method for identifying a subset of gastric cancer with a mutator phenotype and better prognosis.
Wu
Ming-Shiang
MS
Department of Internal Medicine, National Taiwan University Hospital, No. 7 Chun-Shan S. Rd., Taipei, Taiwan.
Lee
Chung-Wei
CW
Sheu
Jin-Chuan
JC
Shun
Chia-Tung
CT
Wang
Hsiu-Po
HP
Hong
Ruey-Long
RL
Lee
Wei-Jei
WJ
Lin
Jaw-Town
JT
D000230:Adenocarcinoma / Q000235:genetics* / Q000382:microbiology / Q000473:pathology / Q000601:surgery; D000368:Aged; D004268:DNA-Binding Proteins; D005260:Female; D016368:Frameshift Mutation / Q000235:genetics; D005743:Gastrectomy; D005819:Genetic Markers / Q000235:genetics*; D016481:Helicobacter Infections / Q000235:genetics; D016480:Helicobacter pylori; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D018895:Microsatellite Repeats / Q000235:genetics*; D008875:Middle Aged; D051718:MutS Homolog 2 Protein; D009361:Neoplasm Invasiveness; D011184:Postoperative Period; D011379:Prognosis; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D000077294:Receptor, Transforming Growth Factor-beta Type II; D018125:Receptors, Transforming Growth Factor beta / Q000235:genetics; D013274:Stomach Neoplasms / Q000235:genetics* / Q000382:microbiology / Q000473:pathology / Q000601:surgery; D016019:Survival Analysis
D004268:DNA-Binding Proteins; D005819:Genetic Markers; D011518:Proto-Oncogene Proteins; D018125:Receptors, Transforming Growth Factor beta; D017346:Protein Serine-Threonine Kinases; D000077294:Receptor, Transforming Growth Factor-beta Type II; C497172:MSH2 protein, human; D051718:MutS Homolog 2 Protein