Changes Of Enteric Viruses During The Development Of Adenoma Pathway In Colorectal Cancer

Objectives:Colorectal cancer(CRC)accounts for approximately 10% of all cancers and cancer-related fatalities diagnosed globally at present.Researches show that CRC has three kinds of pathogenesis,namely,adenoma pathway,inflammation pathway and de novo pathway.About 70-90% of CRC develops through adenoma pathway.Although the current research on CRC has focused extensively on gut microbiota,the changes of enteric viruses in adenoma pathway of CRC have not been fully recognized.Therefore,this study analyzed the changes of virus-like particles(VLPs)in the feces and tissues at different stages of CRC in adenoma pathway,and analyzed the changes of the composition and function of enteric viruses in feces and tissues at different stages of CRC in adenoma pathway,as well as the changes of the coabundance network of virus-bacterial-fungus within and outside the boundary by using the macrogenomics,providing reference for further exploring the role of enteric viruses in adenoma pathway of CRC.Methods:1.From January to October of 2022,feces and tissue samples were collected from the First Affiliated Hospital of Chengdu Medical College.According to the pathological diagnosis,6 cases were included in the normal control group(N),10 cases in the adenomatous polyp group(A),and 12 cases in the colorectal adenocarcinoma group(C).2.VLPs were stained on feces and tissue samples collected from different groups and observed under microscope.3.From 28 feces and 28 tissues samples,DNA was extracted,and metagenomics was employed to acquire the abundance data of each species at different classifications,as well as the abundance data of different functional classifications of the KEGG database.4.ANOSIM,Metastat,PCA and NMDS analysis were used to compare the significant differences of species and functions among different samples.5.Spearman was used to calculate the correlation of different species,and Cytoscape(v3.6.1)drew a microbial interaction network to study the correlation between different species.Result:1.In normal-adenoma-adenocarcinoma,DNA viruses of VLPs in tissues and feces gradually increased,and RNA viruses was relatively stable.2.From the analysis of the species annotation,in the normal-adenomaadenocarcinoma,it is manifested as the decrease of Hendrixvirus,Sitaravirus,Ravivirus and the increase of Roufvirus and Webervicerus in feces samples at the genus level.NF group contains 9 specific viruses,AF group contains 24 specific viruses,and CF group contains 8 specific viruses.Roufvirus increased in tissues samples at the genus level.There was no specific virus in NT group.AT group contained 1 specific virus,and CT group contained 1 specific virus.3.From the comparative analysis of species significance,Anosim analysis showed that there was a difference in enteric viruses between NF group and AF group in feces,and Metastats analysis showed that there were significant differences among the groups of 12 species,including Gammaretrovirus,Roufvirus,Webservicerus,Hendrixvirus,Sitaravirus,Ravivirus,etc.Anosim analysis of tissue samples showed that there was no significant difference in enteric viruses among groups,but there was significant difference in Roseolovirus and Roufvirus between NF group and AF group by Metastats analysis.4.The intra-boundary and even inter-boundary interactions between enteric viruses Roufvirus and bacteria Collins,Lachnoclostridium in feces,as well as enteric viruses Gammaretrovirus and bacteria Enterobacter,Enterococcus,Clostridioides,etc.and fungi Hanseniaspora,Zygosaccharomyces,etc.in tissues,may play a role in adenoma pathway of CRC.5.At level 3,feces samples from NF group,AF group and CF group contain 3,70 and 4 specific pathways respectively,and no specific pathway was found in each group of tissue samples.6.From the comparative analysis of function significance,Anosim analysis showed that there was a difference between NF group and AF group in feces samples,and Metastats analysis showed that with the development of normal-adenoma-adenocarcinoma,Protein digestion and absorption pathway is gradually downregulated,DNA replication,Mismatch repair,Homologous recombination pathway is gradually up-regulated.while Biosynthesis of amino acid,Propanoate metabolism,Valine,leucine and isoleucine degradation,beta-Alanine metabolism pathway was up-regulated in AF group and CF group than in NF group,but there was no significant difference between AF and CF groups.Anosim analysis showed that there was no significant difference between the groups in tissue samples.Metastats analysis showed that HTLV-1 infection pathway in AT group was up-regulated than NT group.Conclusion:During the development of adenoma pathway in colorectal cancer,changes have taken place in the VLPs,the composition of enteric viruses(such as Gammartrovirus,Jedunavirus,Roufvirus),the coabundance network between viruses,bacteria,and fungi,and metabolic pathways in feces;Changes have also occurred in the VLPs,the composition of enteroviruses(such as Roufvirus and Roseolovirus),the coabundance network between viruses,bacteria,and fungi,and metabolic pathways in tissues.These findings have provided certain reference for exploring the role of enteric viruses in the occurrence of colorectal cancer,but the mode of action and specific mechanisms need further study.