POU5F1 and neoplasm: The newly acquired stem cell properties are exhibited by increased expression of stem cell transcription marker CD133, transcription factors OCT4, Sox2, Nanog, BMI1, Notch1, aldehyde dehydrogenase (ALDH)1, and kinesin family member 4 (Kif4), as well as BMI1 proto-oncogene, polycomb ring finger (Bmi1), increased pneumosphere-forming capacity and tumor-forming ability in NOD/SCID mice [317,318].