The results showed that only tetracycline analogs fed mice, transplanted with U251-E18 cells expressing both IL-13Rα2 and mutant EGFR, had a significantly larger mean tumor volume (Fig. 7a) and tumor weight (Fig. 7b) compared to control groups or mice transplanted with wtEGFR, i.e., U251-E6 cells with or without doxycycline treatment. The gene discussed is IL13RA2; the disease is neoplasm.