POU5F1 and lung cancer: In a variety of human malignancies, such as breast cancer [10], ovarian cancer [11], colon cancer [11], melanoma [11], kidney cancer [11], bladder cancer [12], and lung cancer [13], the high expression of OCT4 indicates that the tumour has a stronger ability of proliferation, invasion and metastasis and is also closely related to drug resistance and recurrence of radiotherapy and chemotherapy.