Assertion: brain tumor's type | /r/HasProperty | protein
Facets:
Source sentences:
text: Monoclonal antibodies are multiple copies of a single antibody that act as a homing device to fit one—and only one—type of antigen (a protein on the surface of the tumor cell that stimulates the immune system response).
text: Several different types of kinase inhibitors—proteins that block growth-signaling enzymes without harming normal cells—have been identified and approved for cancer treatment.