Cancer Targeted Therapy

Cancer targeted therapy is the foundation of precision medicine; it uses drugs or other substances to target specific genes and proteins that control cancer cells’ growth, division and spreading. Compared to traditional chemotherapy drugs, targeted-drugs can specifically act on cancer cells with high efficacy without damaging normal cells. Drugs used in cancer targeted therapy mainly includes small molecules and macromolecules (e.g., monoclonal antibodies), which can target cancer cells and constituents in the tumor microenvironment to activate the immune system. Anti-angiogenesis drugs, such as those targeting vascular endothelial growth factor (VEGF), epidermal growth factor receptor (EGFR), transforming growth factor (TGF)-α, TGF-β, Tumor necrosis factor (TNF)-α, and platelet-derived endothelial growth factor (PDGFR) inhibit the proliferation and metastasis of cancer cells. In recent years, the proportion of antibody drugs in cancer treatment has gradually become prominent. Antibody-drug conjugates (ADCs) are a new type of targeted drugs that are composed of monoclonal antibody, cytotoxic drug and linker. ADCs can deliver drugs to tumor cells and minimize the toxicity to normal tissues. Proteolysis-targeting chimera (PROTAC) is a useful technology for targeted protein degradation. PROTAC exploits the ubiquitin-proteasome system and forms a ternary complex with a hijacked E3 ubiquitin ligase and target protein, leading to polyubiquitination and degradation of the target protein.

Targeted therapy is a useful strategy in treatment of cancer either alone or in combination with standard chemotherapy. At present, targeted therapy has proved significant clinical success in the treatment of many types of cancer, including breast cancer, colorectal cancer, leukemia, ovarian cancer and lung cancer.