By exogenous introduction of these seven lysine to alanine‐substituted EML4‐ALK proteins into two NSCLC cells expressing endogenous EML4‐ALK protein, we found that four EML4‐ALK proteins, all of which included K1610A substitution commonly, revealed significant reduction of phosphorylation of serine 473 in AKT, one of the growth‐signaling molecules activated by EML4‐ALK, and showed the dominant‐negative growth‐suppressive effect on these two cancer cell lines. This evidence concerns the gene ALK and cancer.