CDK4 and sarcoma: CDK4 gene amplification in sarcomas has been observed in both bone and soft tissue tumors, while MDM2 gene amplification predominates in soft tissue tumors, often without coamplification of other genes in the 12q13-q15 region [77,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108].