Abstract: PURPOSE: To establish a vascularized model of patient-derived organoids(PDOs) from oral squamous cell carcinoma(OSCC) patients and optimize the design of preclinical research models. METHODS: Recombinant vascular endothelial cells (R-VECs) overexpressing the ETV2 gene were constructed by lentiviral infection of human umbilical vein endothelial cells(HUVECs). Tumor cells were isolated from OSCC surgical samples and cultured three-dimensionally in Matrigel to self-assemble into PDOs, with the growth dynamics of the model recorded. Hematoxylin-eosin(HE) staining and immunohistochemistry(IHC) were used to detect the expression differences of OSCC markers(CK56, SMA, Ki67) between the PDO model and the patient's primary tumor tissue, so as to evaluate their biological consistency. R-VECs were co-cultured with PDOs. Immunofluorescence (IF) technology was used to detect the proliferative activity of PDOs and the attachment of vascular networks after co-culture, and the structural characteristics of blood vessels inside PDOs were observed by confocal microscopy. RESULTS: A co-cultured vascularized model of R-VECs and OSCC PDOs was successfully established. HE and IHC identification showed that the PDO model was highly consistent with the patient's primary tumor tissue in terms of morphology and marker expression. The vascularized PDO model had significantly enhanced proliferative activity and improved passage stability. HE, IHC, IF and confocal experiments all confirmed that vascular structures could effectively penetrate into the interior of organoids. CONCLUSIONS: The PDO model constructed from OSCC samples can well recapitulate the morphological and biomarker characteristics of the patient's tumor tissue. Vascularization modification can further enhance the proliferative activity of PDOs without changing their inherent tumor biological properties.

Key words: Oral squamous cell carcinoma, Organoid, Vascularization, ETV2, Endothelial cell, Co-culture