Gut microbiota in different stages and subtypes of colorectal cancer in Nairobi, Kenya
Document Type
Article
Department
Pathology (East Africa)
Abstract
Background: Sub-Saharan African colorectal cancer (CRC) incidence is rising with delayed diagnosis being common since the population does not have access to many screening programs. Alterations in gut microbiota have been associated with CRC, although not much is known from cohorts in Africa.
Aims: To characterized and compare mucosal gut microbiota in Colorectal Cancer (CRC) stages and pathology subtypes to identify the biomarkers.
Study Design: A case-control study. Place and Duration of Study: Department of Pathology, Aga Khan University Hospital (AKU) and Jomo Kenyatta University of Agriculture and Technology (JKUAT), between January 2021- December 2023. Methodology: We analyzed 60 Formalin-fixed Paraffin wax-embedded (FFPE) colorectal biopsy samples (30 cases and 30 controls) of patients from Aga Khan University Hospital. We processed the tissues histologically, extracted the DNA and analyzed through 16S rRNA gene PCR amplification and sequencing. Taxonomic assignment was calculated by Biological Locus Alignment Sequence Tool (BLAST) against the NCBI 16S microbial database.
Results: Major bacterial species that were found in CRC were Oscillospiraceae bacterium, Clostridales bacterium, Acetivibrio sp., Eubacterium, Texcoconibacillus texcoconensis, and Staphylococcus sp. Stage II CRC was of greater microbial richness than Stage III. Mucinous adenocarcinoma was associated with Firmicutes commensals, and invasive adenocarcinoma with pathogenic members like Bacillus cereus and Staphylococcus spp.
Conclusion: Gut microbiota community structure is stage and subtype-specific in CRC. The shift from commensal to pathogenic bacteria suggests that microbial dysbiosis has the potential to contribute to the development of CRC. Microbiota profiling may assist in the early diagnosis of CRC and guide individualized diagnostic strategies in African populations.
Publication (Name of Journal)
Journal of Advances in Medicine and Medical Research
DOI
https://hal.science/hal-05303550v1
Recommended Citation
Ogutu, M.,
Andrew, N.,
Mourine, K.,
Sayed, S.
(2025). Gut microbiota in different stages and subtypes of colorectal cancer in Nairobi, Kenya. Journal of Advances in Medicine and Medical Research, 37(10), 101-110.
Available at:
https://ecommons.aku.edu/eastafrica_fhs_mc_pathol/317