Extended Human Papillomavirus Genotype Distribution and Cervical Cytology Results in a Large Cohort of Chinese Women With Invasive Cervical Cancers and High-Grade Squamous Intraepithelial Lesions

Human papillomavirus (HPV) infection is associated with the vast majority of cervical cancer cases as well as with other anogenital cancers. PepCan is an investigational HPV therapeutic vaccine for treating cervical high-grade squamous intraepithelial lesions. The present study was performed to test whether the cervical microbiome influences vaccine responses and to explore host factors as determinants of the cervical microbiome composition in women with biopsy-proven high-grade squamous intraepithelial lesions. In a recently completed Phase I clinical trial of PepCan, histological response rate of 45% (14 of 31 patients), a significant increase in circulating T-helper type 1 cells, and a significant decrease in HPV 16 viral load were reported. DNA, extracted from liquid cytology specimens collected before and after vaccinations, were amplified and then hybridized to a G4 PhyloChip assay to characterize the microbiome. We describe trends that certain bacterial taxa in the cervix may be enriched in non-responders in comparison to responders ( Padj = .052 for phylum Caldithrix and Padj = .059 for phylum Nitrospirae). There was no difference in bacterial diversity between the 2 groups. A permutational analysis of variance performed for various demographic and immune parameters showed significant clustering with microbiome beta diversity for race, HPV 16 status, peripheral T-helper type 1 cells, and HLA-B40 ( P = .001, .014, .037, and .024, respectively). Further analyses showed significant differences at the empirical Operational Taxonomic Unit level for race and HPV 16 status. As these results are from a small Phase I study, further studies are needed to examine the role of cervical microbiome in response to HPV therapeutic vaccines.

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Relationship between the Cervical Microbiome, HIV Status, and Precancerous Lesions

mBio ◽

10.1128/mbio.02785-18 ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 18

Author(s):

Cameron Klein ◽

Daniela Gonzalez ◽

Kandali Samwel ◽

Crispin Kahesa ◽

Julius Mwaiselage ◽

...

Keyword(s):

Hiv Positive ◽

High Grade ◽

Squamous Intraepithelial Lesions ◽

Cervical Lesions ◽

Cervical Cancers ◽

Bacterial Microbiome ◽

Bacterial Richness ◽

Intraepithelial Lesions ◽

Hiv Negative

ABSTRACT Nearly all cervical cancers are causally associated with human papillomavirus (HPV). The burden of HPV-associated dysplasias in sub-Saharan Africa is influenced by HIV. To investigate the role of the bacterial microbiome in cervical dysplasia, cytobrush samples were collected directly from cervical lesions of 144 Tanzanian women. The V4 hypervariable region of the 16S rRNA gene was amplified and deep sequenced. Alpha diversity metrics (Chao1, PD whole tree, and operational taxonomic unit [OTU] estimates) displayed significantly higher bacterial richness in HIV-positive patients (P = 0.01) than in HIV-negative patients. In HIV-positive patients, there was higher bacterial richness in patients with high-grade squamous intraepithelial lesions (HSIL) (P = 0.13) than those without lesions. The most abundant OTUs associated with high-grade squamous intraepithelial lesions were Mycoplasmatales, Pseudomonadales, and Staphylococcus. We suggest that a chronic mycoplasma infection of the cervix may contribute to HPV-dependent dysplasia by sustained inflammatory signals. IMPORTANCE HPV is known to be the causal agent in the majority of cervical cancers. However, the role of the cervical bacterial microbiome in cervical cancer is not clear. To investigate that possibility, we collected cervical cytobrush samples from 144 Tanzanian women and performed deep sequencing of bacterial 16S rRNA genes. We found that HIV-positive patients had greater bacterial richness (P = 0.01) than HIV-negative patients. We also observed that women with high-grade squamous intraepithelial lesions (HSIL) had greater cervical bacterial diversity than women with cytologically normal cervices. Data from our precise sampling of cervical lesions leads us to propose that Mycoplasma contributes to a cervical microbiome status that promotes HPV-related cervical lesions. These results suggest a greater influence of the bacterial microbiota on the outcome of HPV infection than previously thought.

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