Dissecting Ras-activation of NF-kB-dependent cytokine production

• Grant number: 22/08915-7
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• Effective date (Start): November 01, 2022
• Effective date (End): April 10, 2023
• Field of knowledge: Biological Sciences - Immunology
• Principal Investigator: João Gustavo Pessini Amarante Mendes
• Grantee: Ronaldo Rodrigues Ribeiro
• Supervisor: Seamus J Martin
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Research place: Trinity College Dublin, Ireland
• Associated to the scholarship: 20/03304-4 - Analysis of RASSF9 function in melanoma in 2D and 3D models, BP.MS

Abstract

Inflammation is one of the hallmarks of cancer progression and initiation. Constant exposure to inflammatory stimuli can lead to a chronic response that has been highly associated with tumor progression. The main signaling in inflammation occurs through the NF-ºB (nuclear factor ºB) pathway, which has already been shown to be modulated by Ras, acting both as anti and proinflammatory. Ras is a small GTPase protein of three major subtypes, KRas, HRas, and NRas, that are involved in numerous physiological processes. For instance, in a variety of tumors, oncogenic KRas is involved in upregulating cytokine and chemokine production, promoting tumor progression, growth, migration, and angiogenesis. However, the exact mechanism responsible for Ras-initiated NF-ºB activation and cytokine production remains obscure. The main focus of our current project is to investigate the RASSF family, with a special emphasis on RASSF9. Due to the presence of a Ras Association (RA) domain, the RASSF family members are major effectors of Ras, and some of those members, like RASSF1, 2, 5, 6, and 8, have already been associated with NF-ºB, but their exact role in inflammation has not been investigated. In this project, we will address these questions using the in vitro Human Ovarian Surface Epithelial (HOSE)-HRasV12 model. The treatment with doxycycline (Dox), induces oncogenic HRasV12 in those cells. We will knock down candidate genes that may participate in the Ras/NF-ºB signaling and, after inducing Ras expression, we will analyze cytokine and chemokine production, as well as expression of key proteins.