Tumor Cells in Blood Samples Predict Prostate Cancer Spread

Epithelial to mesenchymal transition (EMT) is a critical step for tumor metastasis and in prostate cancer; circulating cells expressing the mesenchymal marker Vimentin (VIM) are cancer cells.

Scientists at the Barts Cancer Institute (London, UK) studied 81 samples from men with prostate cancer, comprising 38 untreated and 43 progressive diseases, and looked for cells that were gaining the ability to migrate and invade through the body. They optimized the Parsortix size and deformability-based platform (ANGLE, Plc, Guilford, UK) for the isolation of CTCs with both epithelial and mesenchymal properties and developed a multiple fluorescence in situ hybridization (FISH) rehybridization method to analyze multiple genomic changes on the CTCs after immunofluorescence signals were completely stripped.

The team analyzed several genomic regions, and detected genomic alterations in a similar proportion of CK+ and VIM+ groups of CD45- circulating cells. These genomic aberration results indicate that majority of VIM+/CD45- cells are circulating prostate cancer cells with EMT. Among the CTC types, the number of EMTing CTCs correlated the best with the presence of metastases and high risk localized disease and had a closest area under the ROC curve (AUC) to prostate specific antigen (PSA) level for distinguishing patients with detectable metastases.

The authors of the study concluded that they had developed a novel CTC detection and genomic analysis approach, which can efficiently analyze CTCs undergoing/undergone EMT. This greatly enhances our ability to investigate cancer metastasis process and to predict/monitor cancer progression using CTCs. Yong-Jie Lu, MD, PhD, the lead author said, “Our study shows that the number of these specific cells in a patient's sample is a good indicator of prostate cancer spreading. By identifying these cells, which have gained the ability to move through the body, we have found a potential new way to monitor the disease.” The study was presented at the National Cancer Research Institute Cancer Conference held in Liverpool, UK.

Related Links:
Barts Cancer Institute
ANGLE