The U-2 OS cell line, originally known as the 2T line, was cultivated from the bone tissue of a fifteen-year-old human female suffering from osteosarcoma. Established in 1964, the original cells were taken from a moderately differentiated sarcoma of the tibia. U-2 OS cells have a very high proliferation rate and are extremely robust in experimental procedures. These make them attractive for not only cancer research but other areas of research which need cells for in vitro experiments.