HAS 2 ( hyaluronan synthase 2 )

Hyaluronan is catalyzed by three membraneembedded HA synthases, although HAS2 is the only essential gene. The isozymes are coded by 3 separate genes that, although related, are unlinked in the chromosome. Regulation occurs at trans-cription, posttranslational levels, as well as, by alternative splicing, differential sub-cellular locali-zation and epigenetic processes. Hyaluronan deposits in the extracellular matrix have been associated with a variety of cellular processes such as motility, adhesion, division, morphogenesis, wound healing and vascular development. HAS2 overexpression, as well as, amplification of locus 8q24.12, has been implicated in tumor proliferation and metastasis in genitourinary tumors. Recently, the degree to which HA synthases can overexpressed has suggested the likelihood the gene may play contradicting roles as tumor suppressor and oncogene.