Champelovier P, Mongelard F, Seigneurin D
Laboratoire de Cytologie, Centre Hospitalier Universitaire de Grenoble, France.
Anticancer Res. 1999 May-Jun;19(3A):2073-8.
The suitability of CK20 mRNA expression as a marker for the detection of minimum residual disease in patients with cancer of epithelial origin was evaluated. A sensitive nested RT-PCR assay with multiple replicates was optimised to detect a minimum number of circulating tumor cells expressing cytokeratin 20 (CK20) mRNA. Using this optimal procedure, we examined CK20 mRNA expression in ten epithelial and seven leukemic cell lines, in eight bladder tumors, in peripheral blood samples from 18 tumor patients and from 29 healthy controls and in 8 bone marrow samples from healthy donors. CK20 mRNA was found in 13 of 18 (72%) blood samples from patients with cancer of epithelial origin and in all the epithelial tumor cells tested. However, CK20 mRNA was also detected in 21 of 29 (72%) bloods, in 8 of 8 bone marrow samples from healthy donors and in 4 of 7 leukemic cell lines. These results highlight a requirement for either determination of threshold levels of CK20 normal expression or the development of quantitative techniques to distinguish between a tumor-specific CK20 gene expression and a low level background transcription of this marker. These results would also advise caution in using CK20 as a tumor specific marker in clinical investigations.
评估了细胞角蛋白20（CK20）mRNA表达作为上皮源性癌症患者微小残留病检测标志物的适用性。优化了一种具有多个重复的灵敏巢式逆转录聚合酶链反应（RT-PCR）检测方法，以检测表达细胞角蛋白20（CK20）mRNA的循环肿瘤细胞的最小数量。使用此优化程序，我们检测了10种上皮细胞系和7种白血病细胞系、8个膀胱肿瘤、18例肿瘤患者和29例健康对照的外周血样本以及8例健康供体的骨髓样本中的CK20 mRNA表达。在18例上皮源性癌症患者的13份（72%）血样以及所有检测的上皮肿瘤细胞中发现了CK20 mRNA。然而，在29份血样中的21份（72%）、8例健康供体的8份骨髓样本中的8份以及7种白血病细胞系中的4种中也检测到了CK20 mRNA。这些结果凸显了确定CK20正常表达阈值水平或开发定量技术以区分肿瘤特异性CK20基因表达和该标志物低水平背景转录的必要性。这些结果也提示在临床研究中使用CK20作为肿瘤特异性标志物时应谨慎。
