cancers Review Making Connections: p53 and the Cathepsin Proteases as Co-Regulators of Cancer and Apoptosis Surinder M. Soond 1,*, Lyudmila V. Savvateeva 1, Vladimir A. Makarov 1, Neonila V. Gorokhovets 1, Paul A. Townsend 2 and Andrey A. Zamyatnin, Jr. 1,3,4,* 1 Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Trubetskaya Str. 8-2, 119991 Moscow, Russia;
[email protected] (L.V.S.);
[email protected] (V.A.M.); gorokhovets_n_v@staff.sechenov.ru (N.V.G.) 2 Division of Cancer Sciences and Manchester Cancer Research Centre, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, and the NIHR Manchester Biomedical Research Centre, Manchester M13 9PL, UK;
[email protected] 3 Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119992 Moscow, Russia 4 Department of Biotechnology, Sirius University of Science and Technology, 1 Olympic Ave, 354340 Sochi, Russia * Correspondence:
[email protected] (S.M.S.);
[email protected] (A.A.Z.J.) Received: 6 October 2020; Accepted: 19 November 2020; Published: 22 November 2020 Simple Summary: This article describes an emerging area of significant interest in cancer and cell death and the relationships shared by these through the p53 and cathepsin proteins. While it has been demonstrated that the p53 protein can directly induce the leakage of cathepsin proteases from the lysosome, directly triggering cell death, little is known about what factors set the threshold at which the lysosome can become permeabilized. It appears that the expression levels of cathepsin proteases may be central to this process, with some of them being transcriptionally regulated by p53.