A Topical Plasmid-based Approach to Cervical Cancer Screening

PROJECT SUMMARY/ABSTRACT The specific objective of this proposal is to demonstrate proof-of-concept for a novel screening approach for cervical cancer (CC) using a topically applied, disease-specific plasmid containing a secreted reporter. CC is the fourth most common cancer in women worldwide. Despite the availability of clinical screening methods and

effective treatments for early stages of CC in the U.S., disproportionately high incidence and mortality due to CC is prevalent in rural Black communities. This disparity is due partly to poor follow-up resulting from socioeconomic barriers and poor access to clinical care in these communities. The long-term goal of this project is to mitigate

these barriers by developing a sensitive, home-based screening approach for CC by means of a diagnostic plasmid. As a first step in achieving the long-term goal, this proposal will test the hypothesis that a topically applied, disease-specific plasmid, containing a secreted reporter protein driven by the Inhibition of Differentiation

1 (Id1) promotor, can be used to detect CC. Id1 has minimal expression in normal adult tissues but is overexpressed in CC, where expression correlates with the stage of disease. Topical application of the plasmid to the cervix would promote transfection via nonspecific endocytosis. Following transfection, CC cells that have

upregulation of Id1, but not normal cervical cells, will secrete the reporter protein into the cervical cavity for non- invasive collection. The experimental approach will use CC cells, CC tissues freshly resected from human patients, and animal models to establish feasibility and specificity for CC screening with a plasmid containing the

Id1 promotor and secreted reporter. Aim 1 will determine correlations between Id1 expression and reporter production in CC cell lines with varying degrees of Id1 expression and in fresh human CC tissues following transfection in vitro. Specificity of reporter production as a function of Id1 and due to the presence of CC relative

to healthy cervical tissue will be evaluated. Aim 2 will establish feasibility for topical application of the plasmid in vivo using mice bearing human CC tumor xenografts. Plasmid-induced reporter production will be measured as a function of time and as a function of the number of transfected cells following topical transfection. The minimum

tumor burden required for reporter-based detection in cervical fluids will be determined. Successful completion of the aims will demonstrate feasibility and specificity of the diagnostic plasmid approach in CC models. Long- term impact: This work will establish the foundation for advancing the plasmid-based approach into future stages

of development using translationally relevant vectors and cervical applicator materials for plasmid delivery and reporter protein collection. Ultimately, we envision a diagnostic approach that in the long-term will enable highly specific, cost-effective, self-applied CC screening to facilitate targeted clinical follow up and treatment for

individuals in high-risk settings associated with reduced access to routine gynecological care.