PTEN and cancer: In summary, the conclusion drawn by the experiments reported here is that mutant AKT1E17K is an oncogene that can initiate cancer in the mouse lung, though its oncogenic potency is apparently weaker than that of other oncogenes acting in the lung such as mutant EGFR, Kras or PIK3CA. Instead, the effects exerted by AKT1E17K are more similar to those elicited by PTEN deficiency.