[Isolation and identification of cancer stem cells from human esophageal carcinoma].
OBJECTIVE
To isolate and identify cancer stem cells from esophageal carcinoma cells (ECCs) using cell surface marker p75NTR.


METHODS
ECCs cell lines were established with ECCs collected from 38 surgically resected specimens. Flow cytometry was used to identify the p75NTR positive cells therein that were isolated then using magnetic activated cell sorting (MACS) method. The growing characteristics in DMEM medium and capability of colony-forming in soft agar of the p75NTR positive cells were evaluated ex vivo with MTT method. p75NTR positive cells of different concentrations were subcutaneously injected into the backs of Balb/c nude mice and PBS was injected into the contralateral back, and then tumorigenesis was observed, 8 weeks later the mice were killed with their tumors taken out to undergo microscopy.


RESULTS
Eight ECCs cell lines were established, 6 of which were found to contain 0.32%-3.35% of p75NTR positive cells. The purity of p75NTR positive cells isolated by MACS was up to 90%. MTT result showed that population doubling time of the p75NTR positive cells was (17+/-3) hours, significantly shorter than that of the p75NTR negative cells [(37+/-7) hours, P<0.01]. The colony-forming rate in soft agar of the p75NTR positive cells was (45.9%+/-8.9%), significantly higher than that of the p75NTR negative cells [(3.7%+/-2.1%), P<0.01]. As few as 2000 p75NTR positive cells gave rise to new tumors in xenotransplantation, with a tumorigenic ability 50 times as high as that of the p75NTR negative cells.


CONCLUSIONS
p75NTR positive cells carry some properties of cancer stem cells, such as the ability of self-renewal, differentiation and proliferation and demonstrate higher ability of colony-forming ex vivo and tumorigenesis in vivo.
Sun
Zhi-gang
ZG
Department of Cardiothoracic Surgery, Changhai Hospital, Second Military Medical University, Shanghai 200433, China.
Huang
Sheng-dong
SD
Zhang
Bao-ren
BR
Xu
Zhi-yun
ZY
Liu
Xiao-hong
XH
Gong
De-jun
DJ
Yuan
Yang
Y
D000818:Animals; D002454:Cell Differentiation; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D002469:Cell Separation; D004938:Esophageal Neoplasms; D005434:Flow Cytometry; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D014411:Neoplastic Stem Cells / Q000166:cytology*; D017475:Receptors, Nerve Growth Factor / Q000032:analysis; D014410:Tumor Stem Cell Assay
D017475:Receptors, Nerve Growth Factor