The Study Of New Physical Targeting Method For Tumor Cells And Its Targeting Inhibition For Tumor Cells

Cancer is one of the major diseases that threaten human health.Recently,The use of nano-carrier for cancer treatment is expected to significantly improve the drug loading,utilization,and reduce the toxicity of normal tissues and cells has attracted much attention.Traditional targeting methods include active targeting that used receptor-ligand recognition,or passive targeting using magnetic field-induced and enhanced permeability and retention effect(EPR effect).These methods have a certain effect but there are obvious deficiencies.Cancer cells is the much increased level of glycolysis,the loss of the highly mobile lactate from the cytoplasm creating a net of negative surface charges.In this study,we used MCF-7 and He La cell lines with different of Epithelial cell adhesion molecule(EpCAM)protein expression,but the surface with strong negative charge was studied.We contrasted the difference between electrostatic-mediated tumor cell recognition and traditional receptor-ligand mediated recognition efficiency.Upon nanoparticle binidng onto the cancer cells,irradiation by laser is subsquently applied to induce a photothermal hyperthermia that kills the cancer cells directly.Results show that the positively-charged nanoparticles can be bind to the two kinds of tumor cells more quickly and low-energy,while the EpCAM antibody coupling nanoparticles need higher temperature and longer time to bind with MCF-7 cells,which is almost ineffective for He La cells with low EpCAM expression.It shows that electrostatic targeted method is more efficient,rapid and broad-spectrum compared with traditional targeted methods.In order to promote the electrostatic targeted way toward closer to actual application,we use the fetal bovine serum(FBS)incubation to with the nanopaticles to structure protein corona at the surface of nanoparticles,and Well-decorated by protein coronas,the electrically-charged particles retain strong electrostatic interactions with cancer cells,even when the particle Zeta potential is reversed from positive to negative.This behavior is explained by a non-uniform corona modulation of the particle surface charge distributions,exposing locally positively-charged regions,capable of strong electrostatic cell binding and magnetic capturing in a physiological environment.This fundamental discovery paves a new way for sensitive detection of circulating tumor cells in whole blood in clinical settings.