2786 - Development of a living organoid biobank derived from colorectal cancer patients: towards personalized medicine

Background

Organoids are 3D in vitroprimary culture of great interest for translational research representing an efficient and reproducible cancer model. The aim of this project is to generate a biobank of colorectal cancer (CRC) patients derived organoids (PDOs) that could be used to analyze molecular characteristics and to test different treatments as well as to study the underlying molecular causes of cancer and treatment resistance.

Methods

Primary or metastatic CRC tissues have been obtained from patients who underwent surgery. Tissue has been washed and incubated with antibiotics. After mechanical and enzymatic digestion, free cells have been seeded in Matrigel with proper medium. Development of organoids has been observed the day after seeding. Organoids have been passaged, expanded and stored in liquid nitrogen to constitute a biobank. For morphological characterization, after reaching an appropriate volume, organoids have been fixed in 4% paraformaldehyde, stained for hematoxylin and eosin (H&E) and immunohistochemistry (IHC) for ki67, CDX2, CK20, MUC2/5 was performed. Immunofluorescence (IF) for DAPI, Lgr5 and CDH1 has been performed.For genomic characterization, DNA has been extracted with phenol-chlorophorm and sequenced with an internal customized panel. A comparison statistical test with matched tissue has been performed.

Results

The success rate in CRC-PDOs establishment is around 80%. PDOs staining with H&E shows a morphology comparable to the original tissue. IHC shows ki67 staining, nuclear positivity for CDX2, cytoplasmic CK20 and MUC2/5. IF evidences the positivity for the intestinal stem cells marker Lgr5 and CDH1 thus confirms that PDOs faithfully recapitulate original tissue morphology and cell composition.Between 80 and 120 ng of genomic DNA has been sequenced. Spectrum of PDOs mutations and polimorphisms displays a good concordance with that of matched patients with an R of linear concordance of 0.9.

Conclusions

We have developed a robust protocol for efficient development of CRC PDOs. Organoids recapitulate morphological and genomic features of the original patient. They work as a solid in vitromodel, suitable for functional studies and drug screening, helping in promoting precision medicine.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Grants from the Instituto de Salud Carlos III (PI15/02180 to AC and PI18/01508 to TF). FP is supported by the ESMO 2018 fellowship programme. VG was supported by the ESMO 2014 fellowship programme and by Rio Ortega contract CM18/00241 from the Carlos III Health Institute; TF is supported by Joan Rodes contract 17/00026 from the Carlos III Health Institute. NT was supported by Rio Ortega contract CM15/00246 from the Carlos III Health Institute; DR was supported by Joan Rodes contract 16/00040 from the Carlos III Health Institute. MFGB is supported by a Santiago Grisolia fellowship.

Disclosure

A. Cervantes: Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution): Merck Serono; Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution): Roche; Advisory / Consultancy, Research grant / Funding (institution): Beigene; Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution): Bayer; Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution): Servier; Advisory / Consultancy, Research grant / Funding (institution): Lilly; Advisory / Consultancy, Research grant / Funding (institution): Novartis; Advisory / Consultancy, Research grant / Funding (institution): Takeda; Advisory / Consultancy, Research grant / Funding (institution): Astellas; Advisory / Consultancy: Pierre Fabre; Research grant / Funding (institution): Genentech; Research grant / Funding (institution): Fibrogen; Research grant / Funding (institution): Amcure; Research grant / Funding (institution): Sierra Oncology; Research grant / Funding (institution): AstraZeneca; Research grant / Funding (institution): Medimmune; Research grant / Funding (institution): BMS; Research grant / Funding (institution): MSD; Speaker Bureau / Expert testimony: Amgen; Speaker Bureau / Expert testimony: Foundation Medicine. All other authors have declared no conflicts of interest.