http://hdl.handle.net/10256/16187 2025-06-27T02:53:28Z http://hdl.handle.net/10256/16188 Antitumor Ribonucleases Ribó i Panosa, Marc; Benito i Mundet, Antoni; Vilanova i Brugués, Maria Ribonucleases are small basic proteins that have shown remarkable antitumor activity linked to their ability to destroy RNA. Therefore, they are a second line of cancer chemotherapeutics as they are not genotoxic. This chapter summarizes the main biochemical characteristics of these enzymes and the key factors responsible for their cytotoxic mechanism. Some of them are shared by most cytotoxins, but each RNase has particular cancer cell killing abilities. The effects on the cell cycle and the induced apoptosis mechanism are cell dependent. The knowledge obtained from the cytotoxic mechanism of natural cytotoxic RNases has been used to artificially engineer more potent and selective RNA-degrading enzymes. These approaches are also described. The chapter ends with a brief description of the results of the clinical trials performed with RNases 2011-07-12T00:00:00Z http://hdl.handle.net/10256/16181 Approaches to Endow Ribonucleases with Antitumor Activity: Lessons Learned from the Native Cytotoxic Ribonucleases Castro, Jessica; Ribó i Panosa, Marc; Benito i Mundet, Antoni; Vilanova i Brugués, Maria Typical antitumor drugs disrupt the flow of biochemical information from DNA to proteins with the aim of precluding uncontrolled cell proliferation and inducing cancer cell apoptosis. However, most of the currently used small antitumor drugs are genotoxic because they act over DNA. Pharmaceutical industry is now searching for a new line of cancer chemotherapeutics without genotoxic effectsǯ Ribonucleases (RNases) are small basic proteins, present in all life forms, which belong to this kind of chemotherapeutics. Some of them present with remarkable selective antitumor activity linked to their ability to destroy RNA, a powerful way to control gene expression, leaving DNA unharmed. In the last two decades, the knowledge gained on the cytotoxic mechanism of these RNases has been used to engineer more powerful and selective variants to kill cancer cells. In this chapter, we describe the advances reached in endowing an RNase with antitumor abilities 2016-01-01T00:00:00Z