Circulating Tumor Cell Composition in Renal Cell Carcinoma: Beyond the Abstract
Early methods for isolation of circulating tumor cells focused on the isolation cells that expressed the Epithelial Cell Adhesion Molecule (EpCAM). This approach could limit the isolation of circulating tumor cells that undergo epithelial-mesnechymal transition (EMT), losing EpCAM expression the process.
In a new study published by Nel et al. in the journal PLOS One, investigators developed a new isolation approach using multi-parameter immunofluorescence microscopy that includes both epithelial markers such as EpCAM and cells with mesenchymal and stem cell-like characteristics. The investigators obtained peripheral blood drawn from 14 consecutive mRCC patients from a German center. Using this approach, they isolated circulating tumor cells with epithelial, mesenchymal, stem cell-like or mixed-cell characteristics at different time-points during anti-angiogenic therapy.
Interestingly, the investigators identified N-cadherin or CD133-positivity on circulating tumor cells as a marker for lower progression free survival. The study also examined the expression of several anti-angiogenesis genes by quantitative RT-PCR and observed an inverse correlation between high expression of HIF1A, VEGFA, VEGFR and FGFR and the presence of N-cadherin-positive and CD133-positive circulating tumor cells.
This study suggests that patients with RCC have a distinct circulating tumor cells profile and open the door for more studies on using circulating tumor cells as biomarkers for response to anti-angioegnic therapy in this disease.
Written by: Bishoy Faltas, MD
References:
Nel I, Gauler TC, Bublitz K, Lazaridis L, Goergens A, Giebel B, Schuler M, Hoffmann AC. Circulating Tumor Cell Composition in Renal Cell Carcinoma.PLoS One. 2016 Apr 21;11(4):e0153018. doi: 10.1371/journal.pone.0153018. eCollection 2016.