Sama Rezasoltani1, Hamid Asadzadeh Aghdaei2, Hossein Dabiri3, Abbas Akhavan Sepahi4, Mohammad Hossein Modarressi5, Ehsan Nazemalhosseini Mojarad6. 1. Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran. Electronic address: Samasoltani70@gmail.com. 2. Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, P.O.BOX: 1985717411, Tehran, Iran,. Electronic address: Hamidasadzadeh@sbmu.ac.ir. 3. Department of Medical Microbiology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Electronic address: dabirihossein@gmail.com. 4. Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran. Electronic address: akhavansepahy@gmail.com. 5. Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran. Electronic address: modaresi@tums.ac.ir. 6. Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Electronic address: ehsanmojarad@gmail.com.
Abstract
BACKGROUND: Colon cancer (CRC) is a heterogeneous disorder, arising from precursors-adenoma and serrated polyp. Previous studies have demonstrated the relationship between the human gut microbiota and CRC; however, its correlation to the different early precursors of CRC is not properly understood. Here, we studied the relationship between targeted gut bacteria and different colorectal polyp types, location, size and grade of dysplasia. MATERIAL AND METHODS: In the present case-control descriptive study, selected fecal bacteria were assessed in 118 patients, referred for standard screening colonoscopy, including 31 normal controls, 21 hyperplastic polyp (HP), 16 sessile serrated polyp (SSA), 29 tubular adenoma (TA) and 21 villous/tubuvillous polyp (VP/TVP) cases, between 2015 and 2017, by absolute quantitative real time PCR technique (q PCR) in different ethnicity of Iranian population. The panel of bacteria was including Streptococcus bovis/gallolyticus, Enterococcus faecalis, Enterotoxigenic Bacteroides fragilis (ETBF), Fusobacterium nucleatum, Porphyromonas spp., Lactobacillus spp., Roseburia spp., and Bifidobacterium spp. RESULTS: Higher numbers of F. nucleatum, E. feacalis, S. bovis, ETBF and Porphyromonas spp. were detected in AP cases, consisting TA and especially VP/TVP, in contrast to samples from the normal, HP and SSA groups (P < 0.001). On the contrary, lower number of Lactobacillus spp., Roseburia spp. and Bifidobacterium spp. were detected in AP, compared to the normal, HP and SSA. Surprisingly, a significant correlation was found among selected gut bacterial quantity, the size, location and grade of dysplasia of polyp cases. DISCUSSION: These findings suggest that gut bacteria might contribute in early stages of colorectal carcinogenesis through the development of AP, but not SSA. In fact, AP and SSA are also different in terms of molecular pathways and tendencies to present in specific colorectal location. Overall, these findings may lead to development of CRC prevention therapies, targeting early protagonist bacteria of colorectal carcinogenesis from AP.
BACKGROUND:Colon cancer (CRC) is a heterogeneous disorder, arising from precursors-adenoma and serrated polyp. Previous studies have demonstrated the relationship between the human gut microbiota and CRC; however, its correlation to the different early precursors of CRC is not properly understood. Here, we studied the relationship between targeted gut bacteria and different colorectal polyp types, location, size and grade of dysplasia. MATERIAL AND METHODS: In the present case-control descriptive study, selected fecal bacteria were assessed in 118 patients, referred for standard screening colonoscopy, including 31 normal controls, 21 hyperplastic polyp (HP), 16 sessile serrated polyp (SSA), 29 tubular adenoma (TA) and 21 villous/tubuvillous polyp (VP/TVP) cases, between 2015 and 2017, by absolute quantitative real time PCR technique (q PCR) in different ethnicity of Iranian population. The panel of bacteria was including Streptococcus bovis/gallolyticus, Enterococcus faecalis, Enterotoxigenic Bacteroides fragilis (ETBF), Fusobacterium nucleatum, Porphyromonas spp., Lactobacillus spp., Roseburia spp., and Bifidobacterium spp. RESULTS: Higher numbers of F. nucleatum, E. feacalis, S. bovis, ETBF and Porphyromonas spp. were detected in AP cases, consisting TA and especially VP/TVP, in contrast to samples from the normal, HP and SSA groups (P < 0.001). On the contrary, lower number of Lactobacillus spp., Roseburia spp. and Bifidobacterium spp. were detected in AP, compared to the normal, HP and SSA. Surprisingly, a significant correlation was found among selected gut bacterial quantity, the size, location and grade of dysplasia of polyp cases. DISCUSSION: These findings suggest that gut bacteria might contribute in early stages of colorectal carcinogenesis through the development of AP, but not SSA. In fact, AP and SSA are also different in terms of molecular pathways and tendencies to present in specific colorectal location. Overall, these findings may lead to development of CRC prevention therapies, targeting early protagonist bacteria of colorectal carcinogenesis from AP.