[Patient-derived parotid gland pleomorphic adenoma organoid model and its preliminary histological and functional characterization].

Objective: To establish patient-derived organoid models of pleomorphic adenomas (PA) of the parotid gland and preliminarily characterize their histology, related biomarkers and functions. Methods: Fresh tumor tissue specimens were collected from surgical procedures of Oral and Maxillofacial Department. The harvested tissues were processed and cultured in a head and neck tumor organoid culture system to establish organoid models from parotid gland pleomorphic adenomas. The in vitro growth of PA organoids was recorded by light microscopy. The successfully established organoids were passaged and cryopreserved, and the cryopreserved PA organoids were revived and re-cultured to observe their viability and organoid regeneration ability. Histological characterization, as well as characterization and detection of related markers and functional proteins, were performed on the organoids, comparing them with the patient-derived tissues. Results: The constructed organoid model of pleomorphic adenoma exhibited a dense and compact three-dimensional spherical structure. Hematoxylin and eosin staining indicated morphological similarities between the organoid and its tissue of origin. Immunohistochemistry showed positive cytoplasmic staining for Calponin, cytokeratin 7, and epithelial membrane antigen in both the organoid and the source tumor tissue, suggesting consistent histopathological characteristics between the organoid and its tissue of origin. Periodic acid-Schiff staining of the organoid showed positive staining for glycogen, with positive staining located in the interior and periphery of the organoid, indicating that the organoid possessed secretory functions like the salivary gland. Conclusions: This study successfully constructed organoids of pleomorphic adenoma derived from patient samples. This model faithfully replicates the tissue morphology and biomarkers of the source tissue and exhibits biological functions associated with mucus secretion. It serves as a valuable in vitro model for studying the development and progression of salivary gland tumors.