287P - Establishment of nasopharyngeal carcinoma organoid culture system and preliminary exploration of drug sensitivity test in vitro

Background

Nasopharyngeal carcinoma (NPC) has a high incidence among malignant tumors in China, accounting for the highest incidence of head and neck tumors. The treatment of recurrent NPC is difficult, and both the traditional in vitro cell line and PDX models have obvious shortcomings. Therefore, it is imperative to establish better disease models, to study further the mechanism of recurrent NPC, and to explore a more effective treatment method. Tumor organoids are tumor micro-organs in which stem cells are cultured in 3D in vitro. They have been verified by histopathology, molecular biology and genomics, and can retain most of the biological characteristics and tumor heterogeneity of primary tumors, which could be the best models for basic and clinical research. This study aimed to culture and identify NPC organoids using NPC biopsy and resected tissues.

Methods

Fifteen fresh nasopharygeal cancer tissue samples (diagnosed by pathology)were collected from NanFang hospital for 3D culture from June 2018 to December 2019. NPC organoids were collected, fixed with 10% formalin, embedded in paraffin, sectioned, and stained with hematoxylin and eosin. The expression of CD133/CD44/CD47/BMI-1/EBER were detected by immunohistochemistry and in situ hybridization.

Results

1.Successful establishment of nasopharyngeal carcinoma organoid culture system. A total of 50 NPC samples were collected, and 29 organoids were successfully cultured, with a success rate of 58%. There were 16 primary NPC organoids and 13 recurrent NPC organoids. The success rate of culture of primary and recurrent NPC organoids was 47.06% and 81.25%, respectively. The success rate of culture was mainly related to tissue quality and size, specimen pollution, etc. (P= 0.002). 2. The 3D cultures were identified as NPC organoids. The pathological characteristics of HE staining of 3D NPC cultures were consistent with those of parental tumor tissues, which had typical nuclear atypia. The markers, CD133/CD44/CD47/BMI-1 and EBER, were all positivelv expressed in both 3D cultures and parent tumor tissues.

Conclusions

We have successfully established a NPC organoid model which provides a good reference for future study of the molecular mechanism of NPC.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

Li Gang.

Funding

Nanfang Hospital.

Disclosure

All authors have declared no conflicts of interest.