Liquid biopsies in monitoring treatment

Programme stream(s): Treatment
Programme session type(s): Recent Advances session

Chair: Nicholas Turner, The Institute of Cancer Research, UK
Speaker: Johann de Bono, The Institute of Cancer Research, UK
Speaker: Nitzan Rosenfeld, CRUK Cambridge Institute, UK
Speaker: Thomas Wurdinger, Neurosurgical Center Amsterdam, The Netherlands

11:00-12:30

Room: Boisdale

The session will review the technological advances in liquid biopsies, for circulating tumor cells, free circulating tumor DNA and blood cells. The session will review the role in monitoring therapy in the advanced setting, and detect disease in early cancer settings. By the end of the session participants will be able to appreciate the technological and clinical progress in liquid biopsies.

Tumor-educated platelets for the detection and monitoring of cancer
Speaker: Thomas Wurdinger
Affiliation: VU University Medical Center

Abstract:

Blood-based ‘liquid biopsies’ provide a means for minimally invasive molecular diagnostics, overcoming limitations of tissue acquisition. Early detection of cancer, clinical cancer diagnostics, and companion diagnostics are regarded as important applications of liquid biopsies. It has been reported that tumor-educated platelets (TEPs) may enable blood-based cancer diagnostics. Platelets have emerged as central players in the systemic and local responses to tumor growth. Confrontation of platelets with tumor cells via transfer of tumor-associated biomolecules (‘education’) is an emerging concept and can result in the sequestration of biomolecules. Moreover, external stimuli induce specific splicing of pre-mRNAs in circulating platelets. Platelets are considered to undergo queue-specific splice events in response to signals released by cancer cells and the tumor microenvironment – such as stromal and immune cells. The combination of specific splice events in response to external signals and the capacity of platelets to directly ingest (spliced) circulating mRNA can provide TEPs with a highly dynamic mRNA repertoire, with potential applicability to cancer diagnostics. We determined the diagnostic potential of TEPs by mRNA sequencing of platelet samples. Blood platelet samples of >1000 patients with cancer covering multiple tumor types and healthy donors were analyzed. Healthy donors, pan-cancer, and individual cancer classes were distinguished by a self-learning support vector machine (SVM) algorithm, using a set of spliced transcripts with moderate to high expression. These results indicate that blood platelets provide a valuable platform for pan-cancer, multiclass cancer diagnostics, possibly enabling clinical advances in blood-based ‘liquid biopsies’.