ABSTRACT
S ince the seminal paper by Zou et al1 identifying the existence of the novel tumor suppressor maspin (mammary serpin), research efforts have largely focused on the mechanism of action of the protein and its utility as a prognostic indicator for other types of cancer. Maspin regulates tumor cell motility, invasion, growth, and apoptosis. ’ ’4 It has also been identified as a regulator of angiogenesis.5,40 Recently, several molecular targets for maspin have been discovered which include the integrins and, more controversially, the plasminogen activators uPA and tPA.6,7,8 As the number of potential targets and our knowledge regarding the regulation of maspin function increases it would be useful to map these binding sites/functions to an overall framework of maspin structure. Despite the absence of a crystallographic structure for maspin, a model structure has been created which provides a useful starting point for this analysis33-particularly in light of the wealth of published information on other serpin superfamily members, many of which exhibit similar functions.
