Comparison of Gastric Cancer Models Using Different Dimensions In Vitro

Gastric cancer (GC) is one of the most common cancers worldwide due to its late stage of diagnosis. More efficacious models are required to serve as experimental representatives to enhance the effectiveness of various drugs, select suitable treatment regimens for patients, and further investigate the molecular pathological mechanism of GC.

This study utilized four GC cell lines and patient-derived tumor cells (PDTCs) to explore the advantages and disadvantages of the 2D, spheroid, and organoid models, reveal the growth characteristics, drug sensitivity differences, and potential mechanisms of GC cells in different culture models, so as to promote the development of GC models.

A series of experimental approaches were employed, encompassing but not limited to cell growth assessments, drug sensitivity assays, and RNA-sequencing analyses. We demonstrated that the 3D models are more like human tumor tissues in terms of tissue structure and spatial structure. Notably, there are also differences between different 3D models. The results clearly indicate that the sizes of organoids and spheroids differ significantly. The spheroid model had the lowest growth rate among the three models. However, the organoid model achieved the highest cell growth rate among the three models. This may be because the organoid showed significant PI3K/PTEN signaling pathway activation and low expression of the apoptosis-related protein cleaved PARp. Through RNA-sequencing analysis, we found that the biosynthesis and metabolism of the 3D model were higher than those of the 2D model, which may be one of the reasons for the drug resistance of the 3D model. The spheroid model had the lowest drug sensitivity among the three models. We found that the spheroid model had higher expression of metabolic-related molecules, followed by the organoid model and then the 2D model.

Our results show a gap among the three models in the growth characteristics, tissue structure, hypoxia, anti-apoptotic features, signal pathway expression level, and drug sensitivity evaluation of GC cells. These results will further promote the development of GC models.