PO-304 Three-dimensional co-culture of colorectal cancer spheroid with cancer-associated fibroblast as a model to study immune cell modulation

• Published in: ESMO open 2018-07, Vol.3 (Suppl 2), p.A347-A347
• Main Authors: Susanti, S, Raposo, TP, Arsalan, A, Tchoryk, A, Martinez-Pomares, L, Grabowska, A, Ilyas, M
• Format: Article
• Language: English
• ISSN: 2059-7029; 2059-7029
• DOI: 10.1136/esmoopen-2018-EACR25.817

IntroductionColorectal cancer (CRC) is a complex disease in which inflammation is often a prominent feature. Hence, it serves as an appropriate paradigm to unveil the clinical importance of tumour microenvironment especially the infiltrating immune and inflammatory cells in the pathology of the disease. A 3-dimensional (3D) in vitro spheroid co-culture model that allows the interaction with stromal components is considered an essential element in developing a more clinically relevant tumour model. Hence, in this project, we aim to establish a model consisting of different subtypes of CRC and cancer-associated fibroblast (CAF), a major component of the tumour microenvironment, to study the role of immune cells, for example, macrophages, in CRC biology.Material and methodsCRC cell lines, HCT116 and DLD-1, and cancer-associated fibroblast (CAF) isolated from CRC patient tumour tissue were seeded together at the total number 2000 cells/well on 96-well round bottom ultra-low cluster/attachment plates at different ratios (1:1 and 1:2) to form tumour spheroids. Then, different numbers of monocytes isolated from a healthy human volunteer were added (100, 250 and 500 cells) into the CRC-CAF co-culture system. The CRC cells and CAF were stably transduced with TdTomato and GFP fluorescent proteins respectively for microscopic visualisation and monitoring of growth. Spheroid growth was also monitored by volumetric measurement using image analysis software (Fiji).Results and discussionsCo-culture of HCT116 showed that the presence of CAF increased CRC spheroid growth compared to monoculture of the cancer cells. Meanwhile, no growth stimulation of CAF-enriched culture of DLD-1 cells was observed despite the smaller size of the spheroids. Similarly, no enhancement of HCT116 growth was observed when monocytes were added to the co-cultures yet this resulted in the more disrupted morphology of spheroids.ConclusionThis preliminary study highlights the differential enhancement of tumour growth by CAF stimuli on different types of CRC. Further studies on characterisation of the spheroids containing monocytes and the monocyte differentiation are required to investigate their effect on tumour biology. The findings will be correlated to the observation found in our cohort of patient tissues.