Assessing a relation between composition of luminal and tissue microbiota and cervical intraepithelial changes

Abstract

The incidence of cervical cancer (CC) in Russia remains at a high level and ranks fourth among all cancers. CC is preceded by mild, moderate, and severe cervical intraepithelial neoplasia. Human papillomavirus (HPV) is known to be the main cause for its development being responsible for 99% cancer cases. Despite HPV infection, the oncological process occurs only under certain conditions. There are risk factors that indirectly affect the course and emergence of cervical dysplasia. In recent years, the role of cervico-vaginal microbiome for onset and progression of this pathology has been actively discussed. Many studies evidence that dysbiosis along with cervical intraepithelial dysplasia is associated with increased HPV viral load, additionally allowing to clarify a role of specific microorganisms. Despite the knowledge rapidly accumulating about the nature of vaginal microbiome in cervical precancerous processes, the level of its impact on disease course has not been fully investigated and is of great interest. Identification of microorganisms that affect emergence and progression of this pathology will allow to prevent and apply select approach to treatment of dysbiosis. The aim of our study was to identify a relation between cervical tissue and luminal culturome and severe cervical intraepithelial neoplasia. The study evaluated the microbiota of cervical and cervical canal mucosa biopsy in patients with cervical intraepithelial changes. According to the study results, the Streptococcus genus representatives were significantly more frequent in cervical biopsy specimens in severe dysplasia vs. no cervical intraepithelial changes, whereas cervical canal cultures provided comparable data. Bacteria from the Corynebacterium genus were found in cervical biopsy specimens 3 times more often than in smear from the cervical canal mucous membrane. The microbiota from cervical and cervical canal biopsy specimens differ qualitatively and quantitatively particularly regarding prevalence of Streptococcus spp. representatives being more common in patients with cervical dysplasia. Corynebacterium spp. were detected more often in cervical biopsy specimens than in cervical canal smears. Thus, the method of collecting biological material has a great influence on final results.

Keywords

• cervical intraepithelial neoplasia
• cervical microbiome
• biopsy specimen of the cervix
• bacteriological examination
• streptococcus spp.
• corynebacterium spp.