Scale up of organoid expansion and fractionation for their widespread use in preclinical drug discovery

Abstract: Recent studies showing that cancer organoids recapitulate the biology of primary cancers have driven tremendous excitement in their potential to revolutionize drug discovery and personalized medicine [1]. Tumor heterogeneity at the genetic and phenotypic level drives differential responses to therapeutic agents, and this heterogeneity is preserved in organoids grown from colorectal cancers. Using organoids as an alternative to 2D cultures is growing in popularity but there is a bottleneck to their widespread utilization. Organoids need to be produced on a large enough scale to supply end users, from university researchers to pharmaceutical companies; importantly batch-to-batch variation needs to be minimized. Currently, manual processing results in organoids of varied size and while the majority are suitably functional, they range from too small to polarize, to too big with necrotic cores. Cellesce Ltd has developed a new bioprocessing technology by semi-automating the process of organoid culture, thus improving the control of the process conditions, which yields a more desirable range of organoid sizes.

The aim of this research is to fractionate distinct organoid subpopulations based on their size using chemical engineering technologies. Fractionated populations of colorectal cancer organoids from biopsies that show different phenotypes and mutational backgrounds are separated using the technology, and will be used to study differences in organoid subtypes, i.e. function and polarity, and to relate genetic and phenotypic differences back to drug response and primary tumor heterogeneity. This work demonstrated a reduction of drug response variability when size-fractionated colorectal cancer organoids are treated with LGK974 (a porcupine - and thus Wnt secretion - inhibitor) and 5-Fluorouracil (an antimetabolite and ‘Standard of Care’ compound for colorectal cancers).

This approach will enable the use of biophysically-purified organoid subpopulations to study the molecular mechanisms underlying organoids’ phenotypic heterogeneity, together with the efficiency of novel anti-cancer drugs before their use in Phase II clinical trials.