The invention discloses a preparation method of endothelial vesicles of
Escherichia coli for anti-tumor drugs with endogenous high expression of nucleic acids. According to the preparation method of the endothelial vesicles of
Escherichia coli, a 'tRNA scaffolding means' is adopted so as to stably insert
microRNA into a vector; the vector is transformed into
Escherichia coli, thereby allowing highendogenous expression of
microRNA with
cancer-
cell-killing effects; epicellular and periplasmic components of the
Escherichia coli are removed by using
lysozyme, thereby obtaining
protoplast of
Escherichia coli; the
protoplast is filtered by using
polycarbonate membrane, thereby having the
protoplast broken; and then, purification is carried out by adopting a ultracentrifugation means so as to have endothelial vesicles of the protoplast separated, thereby obtaining the endothelial vesicles of
Escherichia coli with high expression of miRNA and
low toxicity. The preparation method provided by the invention is easy to operate, low in production cost, feasible for large-scale
fermentation and preparation, low in
toxicity, and highly efficient. As a novel pharmaceutical carrier, being appliedin anti-tumor
drug preparation, the endothelial vesicles of Escherichia coli are capable of significantly inhibiting development of non-
small cell lung cancer; and thus, the endothelial vesicles of Escherichia coli have broad application prospects in the field of pharmaceutical carriers.