The Detection Of Disseminated Tumor Cells In The Peripheral Blood From Patients With Epithelial Malignancies And The Preliminary Study On The Micrometastic Microarrays

【Objective】 To study the expression of CK19, CK20, CEA, CD44v6 mRNA in the peripheral blood from the patients of epithelial malignancies using RT-PCR technique, and to deduce its clinical significance. To explore the micrometastatic microarrays and apply it to the detection of disseminated tumor cells in the blood.【Methods】 A total of 83 preoperative peripheral blood specimens obtained from patients with epithelial malignancies were studied by CK19, CK20, CEA, CD44v6-specific RT-PCR assay. As control, 15 fresh tumor tissues and blood samples from 15 patients without cancer were also analyzed. The micrometastatic microarrays were designed and established, and the ssDNA (amplified by the asymmetric fluorescent PCR) were hybridized with the microarrays【Results】 The positivity for CK19, CK20, CEA, CD44v6 mRNA expression was 36.1% (30/83), 41.0% (34/83), 48.2% (40/83) and 53.0% (44/83), respectively, in peripheral blood from patients with epithelial cancers. 59% ~ 85.5% was positive for at least one markers. In primary tumors, 15 tumor tissues were all positive for CK19, CK20, CEA, CD44v6 mRNA. In 15 blood samples from nonmalignant control subjects, two were positive for CK19 and CEA respectively, and one was positive for CK20, five were positive for CD44v6. Fifteen samples were hybridized with microarrays, and the results were in accordance with the gel electrophoresis.【Conclusion】 These data indicated that the CK19, CK20, CEA, CD44v6 mRNA expression may be potential biomarkers for detecting micrometastasis and recurrence in peripheral blood with epithelial cancers. It was potentially very useful to use multi-markers in detecting the circulating tumor cells, and a multiple marker PCR assay may help increase PCR positivity. cDNA microarray may be applied to detect the disseminated tumor cells.