Expression, purification of Bauhinia bauhinioides Cruzipain Inhibitor (BbCI) an investigation of action on triple-negative breast cancer cellular events

• Grant number: 22/10383-3
• Support Opportunities: Scholarships in Brazil - Master
• Start date: August 01, 2023
• End date: July 31, 2025
• Field of knowledge: Biological Sciences - Biochemistry - Chemistry of Macromolecules
• Principal Investigator: Maria Luiza Vilela Oliva
• Grantee: Márcia Bonini Galo
• Host Institution: Instituto Nacional de Farmacologia (INFAR). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil
• Associated research grant: 17/06630-7 - Fragments derived from the structure of protease inhibitors with selectivity for inhibition of mammalian and microorganism enzymes and its role as an anti-inflammatory, antimicrobial, antithrombotic and anti- tumor agent: mechanism of action, AP.TEM

Abstract

Proteases are abundant in cells and play an important role in intracellular proteolysis. In breast cancer, the imbalance of these proteolytic enzymes stimulates cell growth and metastasis, acting on the degradation and modification of the extracellular matrix, influencing the regulation and processing of membrane receptors related to tumor growth. Thus, intervention by natural protease inhibitors has been studied as a possible therapy to inhibit proteases involved in carcinogenesis processes. From the seeds of the Bauhia bauhinioides species, an inhibitor of cruzipain, named BbCI, MW 18 kDa was isolated, and the primary sequence of the BbCI shows similarity with other inhibitors isolated from plants belonging to the Kunitz-type family. In addition to cruzipain, BbCI inhibits elastase and cathepsin L, which is highly expressed in breast cancer, facilitating invasion through the extracellular matrix. Thus, the project has as general objectives, the expression, and purification of the recombinant form of BbCI and the investigation of the action of this inhibitor on MDA-MB-231 triple-negative breast cancer cells. 2D and 3D cellular assays will be carried out, relevant to the evaluation the possible antitumor efficacy of the rBbCI inhibitor, contributing to the development of new effective drugs to combat this disease.