STAT3 and breast cancer: STA-21 and its structural analogs, LLL-3 and LLL-12, have shown selectivity for the SH2 domain of STAT3, inhibiting STAT3 dimerization and resulting in suppressed glioblastoma, BCR-ABL leukemias, OvCa, medulloblastoma, and breast cancer cell growth [200,201,202,203,204,205,206,207].