Platelets: The Emerging Clinical Diagnostics and Therapy Selection of Cancer Liquid Biopsies

Abstract

Due to the inherent molecular heterogeneity of metastatic tumours and the dynamic evolution ability of tumour genomes, tumour tissues obtained through biopsy and other methods cannot capture all of the features of tumour genomes. A new diagnostic concept called "liquid biopsy" has received widespread attention in recent years. Liquid biopsy has changed the clinical practice of oncology and is widely used to guide targeted drug utilization, monitor disease progression and track drug resistance. The latest research subject in liquid biopsy is platelets. Platelets originate from multifunctional haematopoietic stem cells in the bone marrow haematopoietic system. They are small cells from the cytoplasm of bone marrow megakaryocytes. Their main physiological functions are to participate in the processes of physiological haemostasis and coagulation. Tumour cells transfer biomolecules (such as RNA) to platelets through direct contact and release of exosomes, which changes the platelet precursor RNA. Under the stimulation of tumour cells and the tumour microenvironment, platelet precursor mRNA is spliced into mature RNA and converted into functional protein to respond to external stimuli, forming tumoureducated platelets (TEPs). The detection of TEPs in the peripheral blood of patients is expected to be used in clinical tumour diagnosis. This emerging liquid biopsy method can replace and supplement the current tumour detection methods. Further research on the role of platelets in tumour diagnosis will help provide a novel theoretical basis for clinical tumour diagnosis.

Prospects of liquid biopsy in the prognosis and clinical management of gastrointestinal cancers

“…TEPs have several clinical utilities in various cancer types apart from gastrointestinal cancers, including breast cancers ( Best et al, 2015 ; Alimirzaie et al, 2019 ; Yao et al, 2019 ; Mendoza-Almanza et al, 2020 ), nasopharyngeal cancers ( Wang et al, 2019c ), prostate cancers ( Tjon-Kon-Fat et al, 2018 ; Boerrigter et al, 2020 ), lung cancers ( Sheng et al, 2018 ; Xing et al, 2019 ), glioblastoma ( Campanella et al, 2020 ; Sol et al, 2020 ; Meng et al, 2021 ), and ovarian cancer ( Mysona et al, 2019 ; El-Arabey et al, 2020 ). Most studies evaluating the role of TEPs have qualitatively reported the RNA profiles of TEPs, whereas the protein profiles of TEPs still remain considerably unexplored.…”

Emerging Role of Tumor-Educated Platelets as a New Liquid Biopsy Tool for Colorectal Cancer

“… 38 In the presence of occult cancer, platelet generation can be severely augmented following numerous tumor-derived and systemic factors. 36 , 39 High TPC has been documented in various cancers 40 ; this high TPC is related to systemic inflammation, 41 and increased potential risk of tumor progression in CRC. 42 Thrombocytosis in adults older than 40 years could be an indicator of cancer 43 and nearly 40% of cases with unknown thrombocytosis (i.e.…”

Circulating Tumour Cells, Cell Free DNA and Tumour-Educated Platelets as Reliable Prognostic and Management Biomarkers for the Liquid Biopsy in Multiple Myeloma

“…Neoplastic cells can relocate molecules such as RNA to platelets via direct connection and delivery of exosomes, which is able to modify the platelet precursor RNA, and under the effect of neoplastic cells and neoplastic milieu platelet immature mRNA is transformed into mature RNA able to form functional proteins, generating TEPs ( Figure 2 ). The identification of TEPs in the peripheral blood of neoplastic subjects is awaiting employment in the tumour diagnosis [ 134 , 135 , 136 ] ( Table 3 ).…”