Circulating tumour cell analysis as an early marker for relapse in stage II and III colorectal cancer patients: a pilot study.

Introduction: Recent studies have identified both the prognostic and predictive utility of determining the number of circulating tumour cells (CTC) in patients with solid cancers.

Material And Methods: In the present pilot study we evaluated the ability of two different methods to isolate CTC in combination with two strategies to enumerate CTC from patients with stages II and III surgically treated colorectal cancer (CRC). First, we used two systems for tumour cell enrichment (differential centrifugation and immunomagnetic beads), combined with two methods to enumerate CTC (real-time PCR and fl ow cytometry), to determine the most efficient combination.

Post-transcriptional regulation of P-glycoprotein expression in cancer cell lines.

The present study of inhibitors shows that the histone deacetylase-induced increase in P-glycoprotein (Pgp) mRNA (MDR1 mRNA) does not parallel either an increase in Pgp protein or an increase in Pgp activity in several colon carcinoma cell lines. Furthermore, studying the polysome profile distribution, we show a translational control of Pgp in these cell lines. In addition, we show that the MDR1 mRNA produced in these cell lines is shorter in its 5' end that the MDR1 mRNA produced in the MCF-7/Adr (human breast carcinoma) and K562/Adr (human erythroleukemia) cell lines, both of them expressing Pgp.