Progress in the Development of Targeted Anti-Tumor Antibody-Drug Conjugates Antibody-drug conjugates (ADCs) are conjugated products of monoclonal antibodies (mAbs) and cytotoxic small molecules. In tumor treatment, although monoclonal antibodies have good targeting properties, most of them target extracellular or cell surface antigens, have weak anti-tumor activity, have limited therapeutic effect on solid tumors, and are more likely to develop drug resistance;...