A PILOT CASE-CONTROL STUDY: MICROBIOME ANALYSIS OF FECAL SAMPLES OF COLORECTALCANCER PATIENTS FROM CHILE AND ARGENTINA

MAYORDOMO, ANDREA CONSTANZA; VALLADARES, CAMILO TAPIA; WOOD, HENRY M.; YOUNG, CAROLINE; ARGUERO, M.JULIETA; BALAGUER, ALBA FUENTES; PAVICIC, WALTER HERNÁN; RISK, MARCELO; QUIRKE, PHIL; MELENDEZ, LUIS CONTRERAS; VACCARO C.A.; PIÑERO T.A.

Viña del Mar

Congreso; XVIII Congreso Latinoamericano de Genética LIV Reunión Anual de la Sociedad de Genética de Chile XLIX Congreso Argentino de Genética VIII Congreso de la Sociedad Uruguaya de Genética I Congreso Paraguayo de Genética V Congreso Latinoamericano de Genétic; 2021

Asociación Latinoamericana de Genética

A PILOT CASE-CONTROL STUDY:MICROBIOME ANALYSIS OF FECALSAMPLES OF COLORECTALCANCERPATIENTS FROM CHILE AND ARGENTINAMayordomo A.C.1, C. Tapia Valladares2, H. Wood3, C. Young3,J. Argüero1, A. Fuentes Balaguer3, J. Fuhr Etcheverry1, W.Pavicic1, M. Risk1, P. Quirke3, L. Contreras Melendez2, C.Vaccaro1, T.A. Piñero1. 1Instituto de Medicina Traslacionale Ingeniería Biomédica (IMTIB) - CONICET - InstitutoUniversitario del Hospital Italiano (IUHI), Hospital Italiano deBuenos Aires (HIBA), Buenos Aires, Argentina; 2Universidadde los Andes, Santiago, Chile; 3Leeds Institute of MedicalResearch at St James?s University Hospital, Pathology &Data Analytics, University of Leeds, UK. tamara.pinero@hospitalitaliano.org.arStudies about the colorectal cancer (CRC) associatedmicrobiome have mainly been conducted in developedcountries with a high incidence of colorectal cancer.In the present work, we compare the CRC-associatedmicrobiome of two developing countries withintermediate CRC incidence, Chile and Argentina.Faecal samples from 10 healthy volunteers (HV) and 10CRC patients from each country were collected usingbowel cancer screening cards. Hiseq Illumina platformwas used for V4 16SrRNA sequencing. Bioinformaticsanalysis was performed by Qiime2 and data was exportedto determine taxa which differed significantly betweengroups using LEfSe. Alpha diversity was calculated andsignificance was assessed by the Kruskal-Wallis test.Weighted/Unweighted Unifrac distance was calculatedand plotted as principal coordinate analysis plots. Thesignificance of differences in beta diversity betweengroups was assessed by PERMANOVA analysis performedusing the Adonis package for R. No significant differencesin bacterial community structure and alpha diversitywere detected. Statistical differences were observedin the beta diversity for unweighted UniFrac distancesbetween the HV and CRC groups from each country. Nodifferences at level of phylum in the relative abundanceof Bacteroidetes, Firmicutes, Proteobacteria, Actinobacteriaand Verrucomicrobia were detected. No significantdifferences in the ratio Firmicutes/Bacteroidetes werefound. The LEfSe analysis showed significant differencesin taxa level independent analysis between HV and CRCgroups in each country. The present work is the firstcomparative study of the faecal CRC-microbiome inSouth American countries. Local projects are underwayto expand the number of patients and validate thepresent results.Global Challenges Research Fund NetworkingGrants/100433.