In the 60 lung cancer patients examined in this study, 28 of 36 (77.8%) smoker patients show increased expression of CIP2A in the tumor samples compared to their adjacent normal specimens, whereas 10 of 24 (41.7%) nonsmoker cases exhibit up-regulated CIP2A at protein level (p = 0.004) (Table 1). Here, CIP2A is linked to lung cancer.