Grant Details
Grant Number: |
5R01CA245894-04 Interpret this number |
Primary Investigator: |
Uhlemann, Anne-Catrin |
Organization: |
Columbia University Health Sciences |
Project Title: |
The Role of the Microbiome in HPV-Associated Cervical Cancer in Women with HIV |
Fiscal Year: |
2023 |
Abstract
Cervical cancer remains an important cause of morbidity and mortality in women, in particular in HIV-infected
women in low and middle-income countries (LMIC), such as South Africa. Testing for human papilloma virus
(HPV), the etiological agent of cervical cancer has significantly improved screen-and-treat approaches at the
point of care in LMIC. However, although persistence of high-risk HPV types is the primary cause of
precancerous cervical intraepithelial neoplasia grade 2 and 3 (CIN2+) and invasive cervical carcinoma (ICC),
its detection has a low positive predictive value, as only a small proportion of HPV+ women will progress to
CIN or ICC. Therefore, there is a compelling need for “triaging” HPV-positive women, to reduce unnecessary
treatment. Once precursor lesions are identified, they are treated by either ablative or excisional methods,
depending on grade. Both of these methods have significant recurrence risk. Better predictors of high-risk
recurrences at the time of treatment as well as potential markers for recurrence post-treatment are needed to
drive down the incidence of cervical cancer. The key factors that promote cancer progression likely reside in
the cervical environment, notably its local microbiome. Preliminary evidence suggests that increased bacterial
diversity and the presence of Lactobacillus iners are associated with CIN2+. L. iners harbors a highly variable
mobile genetic repertoire, containing methylases and toxins that may play a role in progression of cervical
lesions. Elucidating which taxa or genes are predictive of disease state could enable the development of
adjunct rapid diagnostics in HPV+ women. Here we propose to comprehensively study virus-microbiota-host
interactions, specifically the interaction between HPV and lower genital tract commensal bacteria and fungi
relevant to cervical cancer screening in HIV+ and HIV- women. Our group at Columbia University has a long-
standing and highly-productive collaboration with the University of Cape Town, South Africa, with whom we
have undertaken large clinical studies of cervical cancer prevention. We will leverage samples and clinical data
already collected from two of these recent studies. In Aim 1, we will define whether the cervicovaginal bacterial
and fungal communities distinguish between HPV-infected women who have or do not have CIN2+, stratified
by HIV status. In Aim 2, we will test whether cervical microbial taxa at baseline, or changes in taxa over time,
predict recurrence after ablative therapy at 6 or 12 months in women with HPV+/CIN2+. This will inform which
patients require more monitoring, and guide the identification of potential “adjuvant” therapies to improve
efficacy of screening programs by reducing recurrent disease after treatment. In Aim 3 we will apply
metagenomics to identify microbial gene markers and structural genetic variants that predict cervical cancer
treatment failure. Combined, our work will inform potential triage tests to reduce the number of women without
cervical disease beginning treatment, increase the sensitivity for detecting women who are at high risk of
treatment failure, and yield mechanistic insights to help guide the future development of adjunct therapeutics.
Publications
None