110P - Multicellular three-dimensional tumor spheroid of nasopharyngeal carcinoma

Background

Nasopharyngeal carcinoma (NPC) is a squamous cell carcinoma with high metastatic propensity and is often diagnosed at advanced stages, raising public health concerns in its endemic regions such as South China and Southeast Asia. The study of NPC metastasis is hindered by the lack of appropriate models capable to recapitulate the heterogeneous tumour microenvironment in vitro. The current study aims to generate an in vitro model to represent the in vivo biology for NPC and characterize the spheroid invasion in real time.

Methods

To mimic the microenvironment encountered by NPC cells in vivo, heterotypic multicellular tumour spheroids (MCTSs) consisting of triple co-culture of NPC cells (HK-1), fibroblasts (MRC-5), and endothelial cells (HUVEC) was generated using a scaffold-based method. Through histological and immunofluorescence analyses, the morphological characteristic and the organization of the MCTSs were characterized. Tumour spheroid migration assays were conducted on the extracellular matrix (ECM). Quantitative real-time measurements of migration and invasion through an ECM barrier of the MCTSs were conducted by using a real-time cell analyser.

Results

Heterotypic MCTSs constituted from HK-1, MRC-5, and HUVEC formed irregular mass and stellate morphology structure, with loosely arranged cells observed as revealed by H&E staining. The cells demonstrated tumour features including high chromatic and pleomorphism, high nuclear-to-cytoplasmic ratio, mitosis, and necrosis. Immunofluorescence staining showed the presence of NPC cells, fibroblasts, and endothelial cells in the heterotypic MCTSs. Through real-time cell monitoring, this heterotypic MCTSs showed migration and invasion at 1:10 Matrigel with 0.5 μg/μl fibronectin.

Conclusions

The three-dimensional model generated in this study successfully reconstructed the in vivo biology of NPC. To our knowledge, this is the first report on NPC spheroid model that incoporate both tumour and stromal cells. 3D co-culture spheroid is holding a great promise as next generation standard of in vitro pre-clinical model for biomarkers discovery, accelerating drug screening process, and achieving a more precise personalized treatment for cancer patients.

Editorial acknowledgement

Clinical trial identification

Legal entity responsible for the study

The authors.

Funding

Fundamental Research Grant Scheme FRGS (FGRS/1/2020/SKK0/UCSI/02/2) by Ministry of Higher Education (MOHE) Malaysia.

Disclosure

All authors have declared no conflicts of interest.