Organoid studies of cathepsin inhibitors using human pancreatic duct-like cells and the pancreatic cancer cell line MIA PaCa-2

• Grant number: 25/12597-9
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)
• Start date: August 25, 2025
• End date: August 24, 2026
• Field of knowledge: Physical Sciences and Mathematics - Chemistry
• Principal Investigator: Andrei Leitão
• Grantee: Sabrina Mendes Botelho
• Supervisor: Alexander Kleger
• Host Institution: Instituto de Química de São Carlos (IQSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Institution abroad: Ulm University, Germany
• Associated to the scholarship: 20/16799-1 - Study of expression, activity, and inhibition of cathepsins B, L, and S by dipeptidyl nitriles using pancreatic adenocarcinoma cell lines, BP.DD

Abstract

Cysteine cathepsin B and L (CTSB and CTSL) inhibitors present antineoplastic activity, as described in many reports in the literature. There is mounting evidence that these compounds could inhibit cancer progression and metastasis. Compounds 709 and 1031 are inhibitors of cysteine cathepsins, being cytotoxic to the pancreatic (MIA PaCa-2) cancer cells. Here, the mechanism of action for the most promising dipeptidyl nitrile derivative (1031) will be studied using cutting-edge tools to analyze the biological profile of compound 1031 against non-tumoral and pancreatic cancer organoids. The CTSB and CTSL knockout models using the siRNA system will also be made to evaluate further whether the bioactivity of compound 1031 is linked to these cathepsins. The fluorometric assay with the selective probe Z-FR-AMC gives the total amount of cysteine proteases' proteolytic activity. This result can be fine-tuned by differentially querying CTSB and CTSL to determine dipeptidyl nitriles and inhibition and potency of the chemical for each enzyme. Therefore, the bioactivity profile for 1031 could be linked to the diverse phenotypic response previously described by the research group. This study will enable the identification of the bioactivity fingerprint for this novel chemical, providing evidence to support the mechanism of action based on the cysteine cathepsin modulation. (AU)