Prognostic value of circulating CD133(+) cells in patients with gastric cancer.
OBJECTIVE
Gastric cancer is an important cause of cancer-related mortality worldwide (1). There is increasing evidence that the existence of cancer stem cells (CSC) is responsible for tumour formation and maintenance.


METHODS
The present study was designed to recognise circulating CSCs from blood samples of patients with gastric cancer, using CD133 and ABCG2 as potential markers. CD133(-) , CD133(+)  ABCG2(-) and CD133(+)  ABCG2(+) cells lines were analysed by flow cytometry, immunofluorescence staining, western blotting and real-time PCR. Furthermore, functional assays (clonogenic assay in vitro and tumourigenic assay in vivo) were also performed using these cell lines.


RESULTS
Higher percentages of CD133(+) cells were identified in blood samples from gastric cancer patients compared to normal controls. In addition, we found by using Kaplan-Meier analysis, that numbers of CD133(+) cells correlated with poor prognosis gastric cancer patients. Finally, tumourigenic properties of CD133(+)  ABCG2(+) cells were determined in vitro and in vivo.


CONCLUSIONS
Our in vitro and in vivo experiments demonstrated that CD133(+)  ABCG2(+) cells exhibited well-known CSC characteristics; thus when circulating they could be used as a prognostic marker for gastric cancer.
Department of Cell Biology, Basic Medical College of Liaoning Medical University, Jinzhou, Liaoning, 121000, China.
Pu
P
Xia
Chang-Liang
CL
Song
Jin-Fang
JF
Liu
Dan
D
Wang
Xiao-Yan
XY
Xu
D000071916:AC133 Antigen; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters / Q000097:blood / Q000235:genetics*; D000368:Aged; D015703:Antigens, CD / Q000097:blood / Q000235:genetics*; D014408:Biomarkers, Tumor / Q000097:blood / Q000235:genetics*; D063646:Carcinogenesis / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D002999:Clone Cells; D005260:Female; D015870:Gene Expression; D006023:Glycoproteins / Q000097:blood / Q000235:genetics*; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000097:blood / Q000235:genetics*; D009360:Neoplastic Cells, Circulating / Q000378:metabolism* / Q000473:pathology; D014411:Neoplastic Stem Cells / Q000378:metabolism* / Q000473:pathology; D010455:Peptides / Q000097:blood / Q000235:genetics*; D011379:Prognosis; D013274:Stomach Neoplasms / Q000097:blood / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D016019:Survival Analysis
C116614:ABCG2 protein, human; D000071916:AC133 Antigen; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters; D015703:Antigens, CD; D014408:Biomarkers, Tumor; D006023:Glycoproteins; D009363:Neoplasm Proteins; C000606023:PROM1 protein, human; D010455:Peptides