Creation and validation of a global microbiome colorectal cancer reasearch network accross three continents.

WOOD H.; VAN NANG P.; TAPIA VALLADARES C.; QUIRKE P.; YOUNG C.; BOSE M.; CONTRERAS MELENDEZ L.; VACCARO CA; PIÑERO TA; RAMAKRISHNAN S.; VAN DOI M.; FUENTES BALAGUER A.

Mendoza

Congreso; XVII Congreso Latinoamericano de Genética; 2019

ALAG

Research about the colorectal cancer (CRC)-associated microbiome has mainly beenconducted in high CRC incidence ?Western? countries. We have established a global research network to compare the CRC-associated microbiome of high (UK), intermediate (Chile and Argentina) and low (India and Vietnam) CRC incidence countries.Faecal samples from each country were collected using bowel cancer screening cards (10 CRC patients and 10 healthy volunteers) and transported to the UK at room temperature. Replicate control samples from 5 healthy volunteers were generated to assess for the effect of transportation and storage abroad. V4 16SrRNA sequencing was performed. No significant differences in bacterial community structure between any of the UK replicate control samples were found, indicating that transport and local storage of screening card samples does not alter microbiome results.No significant difference was seen in α diversity from the different countries. The β diversity differed among all countries for weighted and unweighted UniFrac distances, with Chile/Argentina and Vietnam/India more similar to one another. β diversity differed between the combined healthy volunteer/CRC groups, with rare CRC-associated taxa (Fusobacterium, Parvimonas, Porphyromonas, Escherichia-Shigella) accounting for this difference.We have demonstrated a robust method of conducting global CRC microbiome research. We have shown that the faecal microbiome differs by country and differences in rare taxa exist between the combined microbiome of healthy volunteers compared with CRC patients. Plans are underway to expand the network and to validate the results at a local level.