The invention discloses a
fusion protein containing mitochondrial pro-apoptotic
protein and a preparation method thereof, and belongs to the technical field of
biomedicine. The
fusion protein is iRGD-MitoPen-Smac N55 (SEQ ID NO: 4), and a triple mechanism of'
tumor targeting-
cell / mitochondrial delivery-
apoptosis activation 'is constructed by connecting an iRGD targeting
peptide, a MitoPen
bifunctional peptide and a Smac N55 active fragment in series. The preparation method comprises the steps of
gene synthesis and optimization, vector construction,
cell transfection expression and affinity purification, and the recombinant
protein with the purity larger than or equal to 94% is obtained. The
fusion protein can be specifically combined with alpha v
integrin highly expressed by
tumor cells and NRP-1, targeted delivery and mitochondrial
apoptosis pathway activation are achieved, proliferation of
tumor cells such as
breast cancer and colon
cancer is efficiently inhibited, in-vivo and in-vitro experiments prove that the anti-tumor effect of the fusion
protein is remarkably superior to that of a Smac simulant LCL161, the fusion protein can be used for preparing anti-tumor drugs, and a new strategy is provided for tumor treatment.