We were unable to clarify the reason why TSG 101 depletion had no impact on cell growth or cell migration of HT1080 or HeLaS3 cells, but expect that the unprecedented link between TSG101 function and MMP-9 mRNA expression provides a clue to reveal the mechanism underlying the controversial functions of TSG101 in carcinogenesis and tumor progression. This evidence concerns the gene TSG101 and neoplasm.