Development of Coagulation Factor Probes for the Identification of Procoagulant Circulating Tumor Cells

Abstract

Metastatic cancer is associated with a hypercoagulable state, and pathological venous thromboembolic disease is a significant source of morbidity and the second leading cause of death in patients with cancer. Here we aimed to develop a novel labeling strategy to detect and quantify procoagulant circulating tumor cells (CTCs) from patients with metastatic cancer. We hypothesize that the enumeration of procoagulant CTCs may be prognostic for the development of venous thrombosis in patients with cancer. Our approach is based on the observation that cancer cells are capable of initiating and facilitating cell-mediated coagulation in vitro, whereby activated coagulation factor complexes assemble upon cancer cell membrane surfaces. Binding of fluorescently labeled, active site-inhibited coagulation factors VIIa, Xa, and IIa to the metastatic breast cancer cell line, MDA-MB-231, non-metastatic colorectal cell line, SW480, or metastatic colorectal cell line, SW620, was characterized in a purified system, in anticoagulated blood and plasma, and in plasma under conditions of coagulation. We conclude that a CTC labeling strategy that utilizes coagulation factor-based fluorescent probes may provide a functional assessment of the procoagulant potential of CTCs, and that this strategy is amenable to current CTC detection platforms.

The prothrombotic activity of cancer cells in the circulation

“…Therefore, the development of thrombosis may not rely on of the mere initiation of coagulation by circulating TF, but rather the magnitude of the host’s coagulation response to that trigger. Our studies have shown that physiological variance of coagulation factors IX and X influence in vitro coagulation kinetics to equivalent procoagulant TF triggers, and evaluation of individual patient coagulation factor levels may hold promise in predicting who is at greater risk to develop thrombosis in the presence of procoagulant TF or CTCs (117). …”

Activation of blood coagulation in cancer: implications for tumour progression

“…Thus, by exposing TF and PS on their outer membrane, tumour cells can function as binding surfaces for different proteins of the coagulation cascade (i.e., factors VIIa, VIIIa, IXa, Xa and Va) [25,26] and promote the subsequent assembly of the prothrombinase and tenase complexes, leading to the generation of fibrin in the extravascular environment (Figure 1). TF expression by tumour cells allows for the formation of the extrinsic tenase complex; establishment of the intrinsic tenase and prothrombinase complexes on the surface of various tumour cell lines has also been described, mainly associated with PS exposure [27–31].…”

Physical Biology in Cancer. 2. The physical biology of circulating tumor cells

“…Tumors and cancer cell lines have been shown to express the transmembrane glycoprotein tissue factor (TF) (7,28,52). TF is the primary initiator of blood coagulation and is expressed by hematopoietic cells (monocytes) and a variety of nonhematopoietic cells (endothelial cells, epithelial cells, smooth muscle cells, and fibroblasts) (29).…”