A. Pituch-noworolska et al., Evaluation of circulating tumour cells expressing CD44 variants in the blood of gastric cancer patients by flow cytometry, ANTICANC R, 18(5B), 1998, pp. 3747-3752
The occurrence of circulating tumour cells in the blood of 51 patients with
gastric cancer (stages I-IV) was studied using flow cytometry, cell sortin
g, immunohistochemistry and reverse trascription polymerase chain reaction
(RT-PCR). The lysed whole blood samples were stained with monoclonal antibo
dies against common leukocyte antigen (CD45), epithelial membrane antigen (
EMA), tumour associated glycoprotein 72kD (TAG72) CD44 variants (nu 5 and n
u 6) and analysed by flow cytometry within ungated or CD45(-) gated populat
ions. The frequency of detection of TAG72 CD44 nu 5(+) and nu 6(+) cells wi
thin CD45(-) gate was considerably increased in comparision to the ungated
population. Furthermore, the presence of tumour cells was directly demonstr
ated by immunostaining for cytokeratin 18 of sorted CD45- population. The p
resence of CD44 nu 5(+), nu 6 cells and CD44 nu-mRNA in the blood was compa
red to their expression in the primary tumour. The occurrence of circulatin
g CD44 nu(+) cells was associated with their presence in the primary tumour
and CD44 nu-mRNA: in the blood. The method described may provide a sensiti
ve tumour marker-independent tool for detection of circulating tumour cells
in cancer patients.