The detection and molecular analysis of circulating tumor cells (CTCs) is an emerging strategy for early diagnosis and monitoring of cancer disease. However, the isolation of rare CTCs from blood samples requires highly sensitive capture methods. Our novel study published in the International Journal of Molecular Sciences gives insight into recent optimization processes in continuation of our previous studies, which showed the feasibility to capture and identify circulating tumor cells (CTCs) based on the recombinant malaria protein VAR2CSA (rVAR2).

Nicolai Tue Sand, PhD student at the University of Copenhagen and leading author of this study, comments: “The discovery that rVAR2, although to a varying degree, binds to most cancer cell lines has far-reaching potential. This study focused on improving the possibly near-universal CTC-capturing platform, particularly for low rVAR2-binding cell lines.”

Notably, we compared the approaches of direct and indirect capture protocols, revealing superiority of the indirect approach in which the capture is divided into two separate incubation steps. With this novel approach, we achieved an enhanced capture of cancer cells, which display only weak rVAR2 binding. This is an important improvement for future studies to enable the capture of CTCs in clinical samples, which could present heterogeneous levels of oncofetal chondroitin sulfate; the target molecule of rVAR2.

“We are very encouraged by the data reported in this publication and look forward to testing and evaluating the optimized capture strategy in clinical patient samples,” comments Mette Ørskov Agerbæk, Director Discovery and Preclinical Development of VarCT Diagnostics.

Publication: Sand, N.T.; Petersen, T.B.; Bang-Christensen, S.R.; Ahrens, T.D.; Løppke, C.; Jørgensen, A.M.; Gustavsson, T.; Choudhary, S.; Theander, T.G.; Salanti, A.; Agerbæk, M.Ø. Optimization of rVAR2-Based Isolation of Cancer Cells in Blood for Building a Robust Assay for Clinical Detection of Circulating Tumor Cells. Int. J. Mol. Sci. DOI: 10.3390/ijms21072401 (https://www.mdpi.com/1422-0067/21/7/2401).