In the CCSP-rtTA/(TetO)7-CMV-Api6 spontaneous lung tumor mouse model, the average CHI3L1 concentration in BALF of doxycycline-treated mice with tumor was 409.8±49.2 ng/ml, compared with that in BALF of doxycycline-untreated mice (82.4±37.1 ng/ml, p<0.001, Figure 3B, upper left panel). This evidence concerns the gene CD5L and neoplasm.