Senescence-Associated β-Galactosidase Detection in Pathology

Abstract

Activity of β-galactosidase at pH 6 is a classic maker of senescence in cellular biology. Cellular senescence, a state of highly stable cell cycle arrest, is often compared to apoptosis as an intrinsic tumor suppression mechanism. It is also thought that SA-β-gal is crucial in malignant cell transformation. High levels of senescence-associated β-galactosidase (SA-β-gal) can be found in cancer and benign lesions of various localizations making the enzyme a highly promising diagnostic marker for visualization of tumor margins and metastases. These findings facilitate the research of therapy induced senescence as a promising therapeutic strategy. In this review, we address the need to collect and analyze the bulk of clinical and biological data on SA-β-gal mechanisms of action to support wider implementation of this enzyme in medical diagnostics. The review will be of interest to pathologists, biologists, and biotechnologists investigating cellular senescence for purposes of regenerative medicine and oncology.

Successful isolation of viable stem cells from cryopreserved microfragmented human adipose tissue from patients with knee osteoarthritis – a comparative study of isolation by tissue explant culture and enzymatic digestion

“…The flow cytometric identification of large granulated senescent cells and small granulated dead cells corresponds well with previous literature on AT-derived stem cells [37]. Cellular senescence can, however, also be identified without SA-BGAL activity, specifically in senescence pathways where lysosomal activity is not involved [36]. Thus, levels of cellular senescence in the samples may be higher than the SA-BGAL assay could detect as only 63% of the cells induced to undergo replicative senescence stained positive with the applied quantitative assay.…”

Comparison of the effects of oxidative and inflammatory stresses on rat chondrocyte senescence

“…Oxidative and in ammatory stresses increased the proportion of SA-β-gal positive cells in this study, indicating that both stresses induced the senescence of rat chondrocytes. β-galactosidase is a lysosomal hydrolase that cleaves the terminal β-D-galactose residue, and its activity is upregulated in cells with senescent features accumulated in aged and diseased organs 15 . SA-β-gal activity is reported to increase in senescent chondrocytes 16 and is now widely used as a biomarker for senescent cells across species and cell origins.…”

Detecting cellular senescence in vivo: Imagining imaging better

“…40 Yet, detection of SA-β-Gal activity is currently the most widely used and well-established method for senescence detection in vitro and in vivo. 34,41 Previously, assessing β-gal activity is useful in the field of molecular biology where it is commonly used as a reporter gene (LacZ), and the imaging probes developed to detect the reporter gene can potentially be explored for their application in senescence research. 42 Also, there have been other lysosomal enzymes proposed to be biomarkers for the senescent state, 43,44 and their association with senescence in various tissue or disease types remains to be validated.…”

“…Overexpression of β‐Gal has been suggested to not be required for the induction and maintenance of senescence 40 . Yet, detection of SA‐β‐Gal activity is currently the most widely used and well‐established method for senescence detection in vitro and in vivo 34,41 . Previously, assessing β‐gal activity is useful in the field of molecular biology where it is commonly used as a reporter gene ( LacZ ), and the imaging probes developed to detect the reporter gene can potentially be explored for their application in senescence research 42 .…”