Cervical Cancer: Could the Microbiome Play a Key Role Alongside HPV?

By Ana Espino | Published on June 03, 2026 | 4 min read


Human papillomavirus (HPV) is widely recognized as the primary cause of cervical cancer. However, not all women infected with high-risk HPV develop precancerous lesions or cancer. This observation has intrigued researchers for years. A review published in Frontiers in Medicine provides new insight: the cervicovaginal microbiome may be a critical factor influencing whether HPV infection progresses to disease.

HPV Is Not the Whole Story

Cervical cancer remains one of the most common cancers among women worldwide, with approximately 640,000 new cases and 350,000 deaths reported in 2022. Although HPV vaccination and screening programs have significantly reduced the disease burden in some countries, disparities in healthcare access continue to contribute to its global impact.

Persistent infection with HPV genotypes 16 and 18 is the primary trigger of cervical carcinogenesis. However, the presence of the virus alone does not explain why some women naturally clear the infection while others develop precancerous lesions or invasive cancer. Researchers are increasingly focusing on the biological environment in which the virus exists, particularly the vaginal microbiome.

A Protective Microbiome—or One That Promotes Disease

In most healthy women, the vaginal microbiome is dominated by bacteria of the Lactobacillus genus, particularly Lactobacillus crispatus. These bacteria help maintain an acidic vaginal pH, strengthen the epithelial barrier, and support local immune defenses against infections.

When this balance is disrupted, a condition known as dysbiosis can occur. Dysbiosis is characterized by a reduction in lactobacilli and an increase in anaerobic bacteria such as Gardnerella, Prevotella, Sneathia, and Atopobium. Numerous studies have shown that these microbial profiles are associated with chronic inflammation, impaired local immunity, and an increased risk of persistent HPV infection.

How Bacteria May Promote HPV Persistence

According to the data reviewed by the authors, women with an imbalanced vaginal microbiome may have a two- to fourfold higher risk of maintaining a persistent high-risk HPV infection. Persistence of HPV is a major factor driving progression to precancerous lesions and cervical cancer.

Several mechanisms may explain this association. Certain bacteria can form biofilms that protect pathogenic microorganisms, interfere with antiviral immune responses, and weaken the epithelial barrier. Others produce metabolites that sustain inflammation or alter the cellular environment in ways that favor tumor development.

Progressive Changes in the Microbiome During Disease Development

Researchers have also observed that microbiome composition changes alongside the progression of cervical lesions.

Early precancerous stages often retain a substantial presence of lactobacilli. In contrast, high-grade lesions and invasive cancers are typically associated with a marked increase in bacteria linked to inflammation and immunosuppression. Certain species, particularly Sneathia, are repeatedly detected throughout the carcinogenic process and may eventually serve as biomarkers for disease progression risk.

The Role of Microbial Metabolites

The microbiome's influence extends beyond the presence or absence of specific bacterial species.

Microorganisms produce a wide range of molecules that can directly affect cervical cells. Some metabolites promote inflammation, oxidative stress, and epigenetic changes involved in tumor development. Others, such as certain short-chain fatty acids, may have protective effects by limiting cancer cell proliferation.

This complex interaction among the microbiome, metabolism, and genetic regulation has led researchers to describe a “microbiome–metabolome–epigenome axis” in cervical carcinogenesis.

Toward New Screening Tools?

One of the most promising perspectives is the use of the microbiome as a biomarker.

Several studies suggest that specific microbial signatures can distinguish women with transient HPV infections, precancerous lesions, or cervical cancer. Some approaches combining microbiological and metabolic data with artificial intelligence have already demonstrated high diagnostic performance.

In the future, these tools could complement existing screening methods and help identify women at greater risk of disease progression more accurately.

Probiotics: A Promising but Still Experimental Approach

In light of these findings, several research groups are exploring strategies aimed at restoring a beneficial microbiome.

Preliminary studies using Lactobacillus-based probiotics suggest improved HPV clearance and reductions in certain cytological abnormalities. Other innovative approaches are also under investigation, including prebiotics, anti-biofilm agents, vaginal microbiota transplantation, and even engineered therapeutic bacteria. 

However, the authors emphasize that current evidence remains insufficient to recommend these interventions in routine clinical practice. Large-scale clinical trials will be necessary to confirm their effectiveness and safety.

A New Dimension in Prevention

This review highlights that the cervicovaginal microbiome is far more than a passive bystander in HPV infection. By influencing inflammation, local immunity, and viral persistence, it may significantly affect the risk of developing cervical cancer.

While HPV vaccination and screening remain the cornerstones of prevention, integrating microbiome analysis could pave the way for a more personalized approach to care—one that identifies high-risk women earlier and offers new preventive or supportive therapeutic strategies.



About the author – Ana Espino
PhD in Immunology, specialized in Virology  
As a scientific writer, Ana is passionate about bridging the gap between research and real-world impact. With expertise in immunology, virology, oncology, and clinical studies, she makes complex science clear and accessible. Her mission: to accelerate knowledge sharing and empower evidence-based decisions.