Fibroblast activation protein (FAP) as a possible target of an antitumor strategy

This review was devoted to the use of the universal component of tumoral stroma (fibroblast activation protein, FAP) as a target of the universal tumor therapy. A tumor is a coevolution system, which includes a microenvironment or reactive stroma differing from the normal tissue in its phenotypic and genotypic features. Cancer-associated fibroblasts (CAFs), which contain the typical marker FAP (serine proteinase with the enzymatic activity of dipeptidyl peptidase and endopeptidase), are important elements of the tumor microenvironment. According to the literature, more than 90% of tumors contain FAP-positive activated fibroblasts. FAP is virtually absent in normal tissues, but it is present in the embryonic and tumor tissues, which makes it a selective and universal target. In this work, basic approaches to affecting CAFs using FAP as a target are discussed. The use of FAP as a target provides an important advantage: its proteolytic activity can be used along with the protein-targeted agents. The main areas of development in the therapeutic use of FAP are discussed in this work.