Is small smarter? Nanomaterial-based detection and elimination of circulating tumor cells: current knowledge and perspectives

Abstract

Alena Gribko,1 Julian Künzel,1 Désirée Wünsch,1 Qiang Lu,1 Sophie Madeleine Nagel,1 Shirley K Knauer,2 Roland H Stauber,1 Guo-Bin Ding1,3 1Nanobiomedicine Department/ENT, University Medical Center Mainz, Mainz 55131, Germany; 2Department of Molecular Biology II, Center for Medical Biotechnology (ZMB)/Center for Nanointegration (CENIDE), University Duisburg-Essen, Essen 45117, Germany; 3Institute of Biotechnology, Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Shanxi University, Taiyuan 030006, People’s Republic of China Abstract: Circulating tumor cells (CTCs) are disseminated cancer cells. The occurrence and circulation of CTCs seem key for metastasis, still the major cause of cancer-associated deaths. As such, CTCs are investigated as predictive biomarkers. However, due to their rarity and heterogeneous biology, CTCs’ practical use has not made it into the clinical routine. Clearly, methods for the effective isolation and reliable detection of CTCs are urgently needed. With the development of nanotechnology, various nanosystems for CTC isolation and enrichment and CTC-targeted cancer therapy have been designed. Here, we summarize the relationship between CTCs and tumor metastasis, and describe CTCs’ unique properties hampering their effective enrichment. We comment on nanotechnology-based systems for CTC isolation and recent achievements in microfluidics and lab-on-a-chip technologies. We discuss recent advances in CTC-targeted cancer therapy exploiting the unique properties of nanomaterials. We conclude by introducing developments in CTC-directed nanosystems and other advanced technologies currently in (pre)clinical research. Keywords: liquid biopsy, cancer biomarker, metastasis, nanomedicine, nanotherapy, therapy resistance

Keywords

• liquid biopsy
• cancer biomarker
• metastasis
• nanomedicine
• nanotherapy
• therapy resistance