Fig. 2.

Application of DARPins in cancer cell visualization and elimination. DARPins can inhibit cell signaling molecules, thus suppressing cell proliferation, or serve as targeting modules for the delivery of various agents: radionuclides, nanoparticles or liposomes, photosensitizers, protein toxins, oncolytic viruses, and lymphocytes with chimeric antigenic receptors. HER2 – human epidermal growth factor receptor 2; NP – nanoparticle; ROS – reactive oxygen species; PI3K – phosphoinositide-3-kinase; Ras – small GTPase Ras; CAR – chimeric antigen receptor; CAR-T – T-lymphocyte expressing the chimeric antigen receptor; FAS – death receptor (CD95, APO-1), an inducer of extrinsic apoptosis pathway; FASL – ligand of the FAS receptor (CD95L, CD178); ETA – truncated Pseudomonas aeruginosa exotoxin A