It provides antibodies and chimeric antigen receptors (CARs) that specifically bind to an epitope containing N-acetyl-glucosamine and/or N-acetyl-galactosamine, e.g., expressed by a cancer cell or an inflammatory cell. Also provided are compositions including these antibodies and/or CARs, as well as polynucleotides, vectors, host cells, methods, and kits related thereto. Further provided are methods and kits for treating or preventing cancer in an individual by administering to the individual an antibody that specifically binds to an epitope containing N-acetylglucosamine or N-acetyl-galactosamine, or a T cell comprising a CAR that specifically binds to an epitope containing N-acetylglucosamine or N-acetyl-galactosamine, optionally in combination with another anti-cancer agent.