Ectopic tumors were dissected from athymic mice injected subcutaneously with cultured primary lung cancer cells derived from either a LSL-KRasG12D;p53fl/fl; CCSP-rtTA+/−;TetO-Cre+/− mouse (LuTDco) or a Nanos3LSL/−;LSL-KRasG12D;p53fl/fl;CCSP-rtTA+/−;TetO-Cre+/− mouse (LuTDNa3). The gene discussed is SCGB1A1; the disease is lung cancer.