INTRODUCTION:Termed as the ‘silent killer’,epithelial ovarian cancer (EOC) earns its nickname due to its high mortality rate, with 5-year survival rates of 46%,46.5% and 38% in UK, USA & Europe respectively.This has been attributed to some extent to the EOC’s high recurrence rate and resistance to currently available platinum based chemotherapeutic treatment methods. Hence,society, researchers and the clinical community are in dire need for a more in-depth study of the EOC microenvironment to design better patient specific treatments and to advance current therapeutic methods.Multiple groups have studied and reported the effect of chemotherapeutic agents on various EOC 3D in vitro models1,2,3. However,there are very few studies wherein a direct comparative study has been carried out between the different in vitro 3D models of EOC and the effect of chemotherapy within them.
Herein, we report for the first time, a direct comparative study of three different 3D in vitro platforms, namely (i) spheroids,(ii) synthetic hydrogels of various chemical configurations and (iii) polymeric scaffolds of various Extracellular Matrix (ECM) compositions on the cell growth and response to the chemotherapeutic(Cisplatin) for ovary derived(A2780) and metastatic(SK-OV-3) EOC cell lines.
METHODS: Spheroids of A2780 and SK-OV-3 cell lines were fabricated using specialized 96 well round bottom plates, provided by faCellitate (Manheim, Germany). Synthetic PeptiGels (Manchester BIOGEL,UK) were used as per manufacturer’s instructions for the hydrogel based culture while polyurethane (PU) scaffold assisted 3D cultures was carried out as per our previously published protocol4,5,6.Cultures were maintained and monitored for different time periods (10–28 days)depending on the culture platform type.Feasibility of using these models for assessment of chemotherapeutic agent (Cisplatin) was also carried out.Various in situ assays for monitoring the cell viability, cellular apoptosis and spatial organisation were also performed.
RESULTS: We report that all three 3D models can support the growth of EOC, but for different time periods (varying from 7 days to 4 weeks).We have seen that chemoresistance to Cisplatin, in vitro, observed especially for metastatic EOC cells, is platform dependent both in terms of structural as well as in terms of biochemical composition of the model/platform.Our study highlights the selection of the appropriate 3D in vitro model depends on the cell type,experimental time period and experimental question being asked as different models are appropriate even when studying the same disease.
CONCLUSION: We have shown the feasibility of using all three model (spheroids, hydrogels and polymeric scaffolds) for the culture of EOC cell lines and assessed the impact of chemotherapy on cell viability and apoptosis within those models. Our study highlights that the selection of a 3D in vitro platform depends on (i) the planned experimental/assessment time period, (ii) the type of cell to be studied, (iii) the site of cell origin in vivo and (iv) the question that needs to be answered.
1.Heredia-Soto, V. et al. Oncotarget 9(2018)
2.Raghavan, S. et al. Gynecologic oncology 138 (2015).
3.Loessner, D. et al. Biomaterials 31(2010).
4.Totti, S. et al. RSC Advances. 8(37):(2018)
5.Gupta, et al. RSC Advances. 9 (71):(2019)
6.Wishart, et al. Cancers. 13(23):(2021)