Nachweis von zirkulierenden Tumorzellen (CTC´s) im Blut von Brustkrebspatientinnen mit Hilfe von spezifischen Real-Time PCR Markern

摘要

It is widely known that cells from epithelial tumors, e.g., breast cancer, detachudfrom their primary tissue and enter blood circulation. We show that the presence ofudcirculating tumor cells (CTCs) in samples of patients with primary and metastatic breastudcancer can be detected with an array of selected tumor-marker-genes by reverseudtranscription real-time PCR. The focus of the presented work is on detecting differences inudgene expression between healthy individuals and adjuvant and metastatic breast cancerudpatients, not an accurate quantification of these differences. Therefore, total RNA wasudisolated from blood samples of healthy donors and patients with primary or metastaticudbreast cancer after enrichment of mononuclear cells by density gradient centrifugation.udAfter reverse transcription real-time PCR was carried out with a set of marker genes (BCSP, CK8, Her2, MGL, CK18, CK19). B2M and GAPDH were used as reference genes.udBlood samples from patients with metastatic disease revealed increased cytokine geneudlevels in comparison to normal blood samples. Detection of a single gene was notudsufficient to detect CTCs by reverse transcription real-time PCR. Markers used here were selected based on a recent study detecting cancer cells on different protein levels. Theudcombination of such a marker array leads to higher and more specific discovery rates,udpredominantly in metastatic patients. Identification of CTCs by PCR methods may lead toudbetter diagnosis and prognosis and could help to choose an adequate therapy.