Ki67 labeling revealed an enhanced proliferation index in JoMa1-ALK-F1174L-derived tumors (48%) compared to JoMa1-ALK-R1275Q- (40%), and JoMa1-ALK-wt-derived tumors (38%) (Figure 3b), suggesting that the accelerated tumor growth of JoMa1-ALK-F1174L tumors may partly result from their increased proliferation capacity. This evidence concerns the gene MKI67 and neoplasm.