Markers of senescence?

The specific identification of cellular senescence in clinical material has important implications for determining the role of senescence in age-related pathologies and in neoplasia in certain tumours. One suggested marker of senescence is the histochemical identification of a specific beta-galactosidase enzyme operative at pH 6.0. However, recent data indicate that this enzyme may not be specific for senescence in all tissues and probably represents the expression of endogenous lysosomal acid beta-galactosidase, which is expressed by a variety of differentiated cell types. Copyright 2002 John Wiley & Sons, Ltd.