Quantification of heparin's antimetastatic effect by single-cell force spectroscopy.
Aaron G LiebschHermann SchillersPublished in: Journal of molecular recognition : JMR (2020)
In circulation, cancer cells induce platelet activation, leading to the formation of a cancer cell-encircling platelet cloak which facilitates each step of the metastatic cascade. Since cancer patients treated with the anticoagulant heparin showed reduced metastasis rates and improved survival, it is supposed that heparin suppresses the cloak's formation by inhibiting the interaction between platelet's adhesion molecule P-selectin with its ligands on cancer cells. To quantify this heparin effect, we developed a single-cell force spectroscopy approach and quantified the adhesion (maximum adhesion force [FA ] and detachment work [WD ]) between platelets and human non-small cell lung cancer cells (A549). A configuration was used in which A549 cells were glued to tipless cantilevers and force-distance (F-D) curves were recorded on a layer of activated platelets. The concentration-response relationship was determined for heparin at concentrations between 1 and 100 U/mL. Sigmoid dose-response fit revealed half-maximal inhibitory concentration (IC50 ) values of 8.01 U/mL (FA ) and 6.46 U/mL (WD ) and a maximum decrease of the adhesion by 37.5% (FA ) and 38.42% (WD ). The effect of heparin on P-selectin was tested using anti-P-selectin antibodies alone and in combination with heparin. Adding heparin after antibody treatment resulted in an additional reduction of 9.52% (FA ) and 7.12% (WD ). Together, we quantified heparin's antimetastatic effect and proved that it predominantly is related to the blockage of P-selectin. Our approach represents a valuable method to investigate the adhesion of platelets to cancer cells and the efficiency of substances to block this interaction.
Keyphrases
- venous thromboembolism
- single cell
- growth factor
- single molecule
- biofilm formation
- rna seq
- squamous cell carcinoma
- small cell lung cancer
- high throughput
- cell proliferation
- heart rate
- staphylococcus aureus
- bone marrow
- mesenchymal stem cells
- oxidative stress
- induced pluripotent stem cells
- pseudomonas aeruginosa
- papillary thyroid
- solid state
- high intensity