Generation of iPSC from patients with Multiple Endocrine Neoplasia type 2 due to RET pathogenic variants

• Grant number: 25/14553-9
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)
• Start date: October 30, 2025
• End date: October 29, 2026
• Field of knowledge: Health Sciences - Medicine - Medical Clinics
• Principal Investigator: Rui Monteiro de Barros Maciel
• Grantee: Mayara Lago Teixeira
• Supervisor: Mirian Romitti
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil
• Institution abroad: Université Libre de Bruxelles (ULB), Belgium
• Associated to the scholarship: 23/02965-5 - RET gene editing via CRISPR/CAS9 in Medullary Thyroid Cancer (MTC) cell-lines, BP.DD

Abstract

Introduction: The missense alteration in Rearranged During Transfection proto-oncogene (RET) gene can lead to medullary thyroid carcinoma (MTC) in multiple endocrine neoplasia type 2A (MEN2A) and type 2B (MEN2 B). Until now, the most common cells used to study the MTC are the TT and the MZ-CRC1 cell lines. Few authors explore the induced pluripotent stem cell (iPSC) to study this specific type of cancer, even though the iPSC model is well established and can generate a unique model for studying tumorigenesis. Objective: We expected to successfully reprogram the patient-derived fibroblast into iPSCs, followed by the differentiation into parafollicular thyroid cells. This will allow us to generate a disease model of MTC with the p.C634W, p.M918T, p.M918V, and p.G533C pathogenic alterations, and also a normal thyroid C cell from a normal fibroblast. Methodology: Fibroblasts cells obtained from patient's biopsy positive for p.C634W, p.M918T, p.M918V, and p.G533C pathogenic alterations will be dedifferentiated with five episomal vectors to an iPS cell line, then this cells are going to be differentiated into C cell from a cell culture treatment with IGF-1, Human Activin A and ITS-A for 15 days. Then, we will perform a characterization of the cells to check their functionality by measuring calcitonin and carcinoembryonic antigen (CEA) secretion, immunofluorescence staining, karyotype, gene expression analysis, bulk-RNA seq, and protein expression by western blotting.