CD33 and glioblastoma: CAR-NK cell strategies are already being tested at clinical and preclinical scale for a variety of solid and hematologic malignancies, including CD19 for B-cell lymphomas [159], CD33 for acute myeloid leukemia [208], CD138 for multiple myeloma [236], HER2 for glioblastoma [237], mesothelin for epithelial ovarian cancer [238], and NKG2DL for colorectal cancer [224], EGFR for many solid tumors [239,240,241,242], ROBO1 for pancreatic carcinoma [243], glioma, and neuroblastoma [244], among others.