Unraveling Tumor Heterogeneity in OSCC through 3D Bioprinting and CRISPR-Based Functional Screening.

• Grant number: 25/21508-0
• Support Opportunities: Scholarships abroad - Research
• Start date: July 01, 2026
• End date: June 30, 2027
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Katiuchia Uzzun Sales
• Grantee: Katiuchia Uzzun Sales
• Host Investigator: Rogerio Moraes Castilho
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Institution abroad: University of Michigan, United States

Abstract

This study will explore serine proteases' functional role in stemness using 3D-bioprinted organoids derived from oral squamous cell carcinoma (OSCC) and CRISPR-based TKI screening. Previous findings from our group indicate that serine protease expression varies according to tumor stage and stemness-associated markers, supporting their potential as prognostic biomarkers and therapeutic targets1-4. Through functional and proteolytic activity analyses, we will generate optimized 3D bioprinted OSCC organoids and identify serine proteases differentially expressed during tumor progression. Selected serine proteases will be individually knocked out using CRISPR-Cas9, and both WT and KO OSCC organoids will be screened using a tyrosine kinase inhibitor (TKI)-focused CRISPR library. The study seeks to uncover which serine proteases affect TKI sensitivity in the context of stemness, to clarify resistance mechanisms, and support the development of new targeted therapies for OSCC. 3D-bioprinted organoids will be examined through proteolytic activity and functional analyses, and mechanistic studies will evaluate the effects of gene silencing on cell growth, genomic stability, and treatment response. With BPE-FAPESP support, a year at the University of Michigan will allow me to acquire practical expertise in advanced methods, which is key to returning these approaches and adjusting them to the Brazilian research context. Working directly with Dr. Castilho, an internationally recognized expert in 3D bioprinting, stemness, and tumor modeling, will make it possible to refine our organoid systems and expand the capacity of experimental oncology in Brazil. The collaboration is also intended to build a long-term partnership between the two institutions and to set the stage for a translational research platform. In addition to publications, the work will yield preliminary data that can support a future FAPESP Thematic Grant, helping to extend the project's scope and impact. (AU)