Unexpectedly, much higher cytoplasmic level of ING5 was found in lung cancer tissues than that in normal lung tissues, suggesting that increased ING5 expression in cytoplasm could serve as a biomarker for lung cancer and may contribute to lung carcinogenesis, and that ING5 translocation from nuclei to cytoplasm might be one reason for increased ING5 in cytoplasm where it lost anti-tumor function. Here, ING5 is linked to lung cancer.