Abstract 37: Characterization of cervical cancer patient derived organoid

Abstract Background: HPV-related cervical cancers pose challenges in murine models due to human-specific viral carcinogenesis. Patient-derived organoids (PDOs) enable to incorporate extracellular matrix and tumor microenvironment, and mirror human tumor features. Methods: Tumor and adjacent tissues were sampled via cytobrushes and resections, and then dissociated, and purified using a Lymphoprep gradient. One million cells were used for scRNA sequencing, while the rest formed PDOs. Baseline tumor and buccal swabs served as genomic controls. PDO identity was validated through immunofluorescent staining, bulk RNA sequencing, and whole exome sequencing (WES). Cell viability assays assessed PDO responses to bacterial metabolites, radiation, and chemotherapy. Results: We established five PDO lines from cervical squamous cell carcinoma (CSCC) and cervical adenocarcinoma (CAC), including one normal PDO from CAC-adjacent tissue. Two primary cell lines were also developed: one from CAC and one from CSCC. Early cultures showed differential KI67 staining: CAC1101, CAC1446, and normal PDOs were positive, while CAC1237 and CSCC1188 were negative. Later cultures showed KI67 positivity across all lines. P63 staining was positive in early CAC1101, CAC1446-adjacent normal, and CSCC1188 PDOs but became negative in late CSCC1188. Only CAC1101 PDOs were PAX8-positive, and PAS staining was observed in all CAC-derived PDOs, including CAC1446-adjacent normal. Somatic mutation analysis revealed 22-46 mutations across most samples, except for Day-14 CAC1101 PDOs, which had 536 mutations. Day-21 CAC1101 PDOs showed 32.6%-54.5% similarity to their tumor swab. CSCC1188 samples exhibited consistent similarity with their tumor swabs (25.9%-40.0%) and within PDOs (37.0%-64.0%). Germline mutation analysis showed 1, 045-1, 918 mutations in most samples, except for Day-14 CAC1101 PDOs, which had 38 mutations. CSCC1188 samples showed higher similarity with their buccal swabs (71.3%-74.0%) and within PDOs (70.4%-78.4%) compared to CAC1101. Comparison of RNA sequencing data of CAC1101 and CSCC1188 showed samples from same patient sharing similar profiles. Cell viability assays indicated that bacterial metabolites increased resistance to radiation and cisplatin in CSCC1188-derived primary cells but had no effect on CAC1237-derived cells. Conclusion: We developed a workflow for generating and expanding PDOs from surgical and non-invasive cytobrush samples while preserving tumor characteristics. PDOs recapitulated the features of their original tumors, offering insights into tumor-microenvironment interactions and variable responses to chemoradiation therapy. Citation Format: Rui Wang, Dalissa Negrón-Figueroa, Xiaogang Wu, Bo Jiang, Barrett C. Lawson, Timothy A. Harris, Maura Gillison, Lauren Colbert. Characterization of cervical cancer patient derived organoid [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 37.