Abstract

In recent years, physiologically relevant 3D
in vitro models of cancer have been continuously refined
due to the need of better mimicking the tumour microenvironment when testing
chemotherapies and immunotherapies. An increasing interest in precision treatment
of cancer patients has highlighted the need for technologies that are capable
of maximising the test of compounds, in isolation and combination, on 3D tumour
models obtained from patient-derived tissue. Microfluidics and organ-on-a-chip
technologies, via precise control of fluids and cells in solution, offer great
opportunities for screening limited amounts of primary tissue in sophisticated,
large-throughput and cost-effective manners.

We have developed and validated a microfluidic
platform for high quality and multiplexed drug screening assays on primary spheroids,
organoids and tumour tissue fragments. Readouts, such as the spheroid
volume, spheroid shape and viability are generated from both brightfield and
epifluorescence microscopy, prior to tissue retrieval. The technology has been
validated using a variety of primary lines, tumour biopsies and resected cancerous
tissue. As examples of diverse and customisable screens: 1) human prostate
biopsies were grown as a heterogeneous co-culture and used for the generation and
screening of thousands of 3D multicellular structures, showing sensitivity to docetaxel,
but resistance to enzalutamide, despite the presence of intact androgen
receptors: 2) co-cultures of several cell types were optimised in our platform
in order to reconstruct a more realistic tumour microenvironment; 3) breast
cancer primary lines and patient-derived cancer-associated fibroblasts (CAFs)
were tested to allow the assessment of the impact of drugs and inhibitors on specific
cell populations; 4) lastly, ovarian tumour tissue fragments were cultured for precision
medicine purposes. These examples give an indication of the screening potential
of our platform for anticancer drug development and precision medicine approaches.