Single Molecular Electron Microscopy Of Her1 And C-met On The Surface Of Triple-negative Breast Cancer Cells

HER1 and c-Met are both highly expressed on the membrane surface of triplenegative breast cancer cells,which are considered as important drug targets in tumor prevention and treatment,however their existence and distribution characteristics on the surface of tumor cell membrane are still remained to be illustrated.In this paper,gold nanoparticles were used to label HER1 and c-Met molecules and ultra-high resolution imaging of HER1 and c-Met molecules on the surface of triple-negative breast cancer cell membranes was performed using scanning electron microscopy.The results showed that HER1 was present in the form of monomers,dimers and multimers on the surface of triple negative breast cancer cells,whose the ratios were 37.98%,12.22 % and 49.80%,respectively.The proportion of monomers of c-Met on MB-231 cell membrane was 39.50% under conventional culture condition,and the proportion of dimer was about 13.44%,and the proportion of multimers was 49.06%.c-Mets are mainly distributed at the edge of the cell compared to central zone.The proportions of monomer,dimer and multimer of c-Met were 88.00%,8.00% and 4.00% under serum-free culture condition for 12 h.The treatment of its ligand HGF is able to dramatically alter the distribution of c-Met on MB-231 cell membrane.The proportions of monomer,dimer and multimer of c-Met were 22.00%,59.00% and 19.00%,respectively,indicating that treatment of HGF significantly enhanced c-Met to form dimers or multimers.This study provide a novel approach to investigate the involvement of cell surface molecules,such as HER1 and c-Met,in the pathogenesis of tumor and to explore more effective preventive or therapeutic techniques against tumor.