[Discovery and verification of matrix gla protein, a TNM staging and prognosis-related biomarker for gastric cancer].
OBJECTIVE
To analyze microarray datasets deposited in the public database and to identify TNM associated genes in gastric cancers.


METHODS
Microarray datasets of gastric cancer were selected from GEO database. Differentially expressed genes related to TNM staging were evaluated by significant analysis of the microarray using MultiExperiment Viewer (MEV) platform. Candidate gene expressions in gastric cancer tissues and cell lines were verified by reverse transcriptase polymerase chain reaction (RT-PCR), quantitative RT-PCR, Western blot and immunohistochemistry.


RESULTS
GES4007 dataset was re-analyzed leading to the identification of 14 genes associated with TNM staging. Over-expression of matrix gla protein (MGP) was confirmed in gastric cancer cell lines and tumor tissues by quantitative RT-PCR, Western blot and immunohistochemistry. Increased MGP expression was found in 22 of 54 cases of (40.7%) gastric cancer specimens compared to the normal gastric tissues. The up-regulation of MGP mRNA expression closely correlated with TNM stage (P = 0.001) and prognosis (P = 0.006).


CONCLUSIONS
Public databases of microarray studies are the valuable resources for data mining. MGP has been identified and confirmed as a novel biomarker for the TNM stage and prognosis of gastric cancer.
Department of Surgery and Shanghai Institute of Digestive Surgery, Shanghai Ruijin Hospital, Shanghai Jiaotong University, School of Medicine, Shanghai 200025, China.
Lei
L
Guo
Xiao-bo
XB
Guo
Jin-ling
JL
Jiang
Jia-nian
JN
Zhang
Jun
J
Ji
Bing-ya
BY
Liu
Zheng-gang
ZG
Zhu
Ying-yan
YY
Yu
D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000096:biosynthesis* / Q000235:genetics; D045744:Cell Line, Tumor; D016326:Extracellular Matrix Proteins / Q000096:biosynthesis* / Q000235:genetics; D005260:Female; D005500:Follow-Up Studies; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D020411:Oligonucleotide Array Sequence Analysis; D012333:RNA, Messenger / Q000378:metabolism; D013274:Stomach Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D015996:Survival Rate; D015854:Up-Regulation; D055815:Young Adult; D000097568:Matrix Gla Protein
D014408:Biomarkers, Tumor; D002135:Calcium-Binding Proteins; D016326:Extracellular Matrix Proteins; D012333:RNA, Messenger; D000097568:Matrix Gla Protein