A team of Rice University bioengineers has developed a new way to create highly realistic “mock” patient samples that could help accelerate the development of faster, more accessible cervical cancer screening tests for low-resource settings.
The study, led by researchers in Rice’s Department of Bioengineering in collaboration with Emory University and clinicians at The University of Texas MD Anderson Cancer Center, addresses a critical bottleneck in global health: the lack of reliable, real-world samples needed to design and validate next-generation point-of-care screening tools for high-risk human papillomavirus, the virus responsible for nearly all cervical cancers. The research was recently published in the Journal of Medical Virology.
“Cervical cancer is highly preventable with effective screening, but millions of women still lack access to those tools,” said Rebecca Richards-Kortum, the Malcolm Gillis University Professor at Rice, co-director of the Rice360 Institute for Global Health Technologies and corresponding author on the study. “Our goal is to help researchers build better tests faster by giving them samples that truly reflect what clinicians see in patients.”
Current gold-standard HPV tests rely on nucleic acid amplification techniques to detect viral DNA or messenger RNA (mRNA). While highly sensitive, these tests are often expensive and require specialized equipment, making them difficult to deploy in low- and middle-income settings, which is where a majority of cervical cancer deaths occur.
“Facilitating the validation and scale-up of technologies that expand access to cervical cancer prevention is essential for global cervical cancer elimination, particularly in low-resource settings where access is urgently needed,” said Dr. Mila Salcedo, assistant professor of Gynecologic Oncology & Reproductive Medicine at MD Anderson and one of the authors of the study.
To develop more affordable, point-of-care alternatives, researchers often rely on simplified or synthetic samples in early testing stages. But those samples often fail to capture the biological complexity of real cervicovaginal specimens, which can lead to delays or failures when tests are evaluated in clinical settings.
“Not all HPV infections look the same,” said first author Emilie Newsham Novak, a former bioengineering doctoral student in Richards-Kortum’s lab. “The amount of viral DNA, whether it’s integrated into human cells or not, the presence of viral mRNA and even things like blood or mucus can vary dramatically from patient to patient. If your test isn’t designed with that variability in mind, it may not perform well in a real-world clinical setting.”
To better understand that variability, the researchers analyzed 32 HPV-positive cervicovaginal samples collected from patients undergoing care. They measured multiple factors relevant to test performance, including viral DNA levels and their structure, viral mRNA levels, cell counts and composition and potential inhibitors like hemoglobin.
The results revealed striking diversity. Viral DNA levels varied by as much as eight orders of magnitude across samples, while mRNA levels spanned nearly nine orders of magnitude. The proportion of viral DNA integrated into human cells (an important indicator of cancer progression) ranged from 0% to 100%. The researchers explained that this kind of variation is why diagnostic development can be so challenging, but their results also provided a blueprint for what realistic test conditions should look like.
Using these insights, the researchers created a standardized method for generating contrived samples that closely mimic real patient specimens. Their approach combines:
- HPV-negative background samples to replicate the natural biological environment
- HPV-positive cells or DNA to simulate infection
- mRNA and other components to reflect disease state
- Controlled levels of potential inhibitors like blood
The researchers demonstrated that these mock samples behave like real clinical specimens when tested using standard laboratory methods and a commercial HPV test. The goal is to allow test developers to systematically test how their assays perform across a wide range of realistic conditions before ever entering a clinical trial, thus significantly shortening the timeline for developing new HPV diagnostics. This is especially true for new technology designed for use at the point of care without access to complex lab infrastructure — key for enabling “screen-and-treat” approaches, where patients can be tested and treated in a single visit, reducing loss to follow-up.
“Better tools mean earlier detection, and earlier detection saves lives,” Richards-Kortum said. “If we can help bring effective, affordable screening to more women around the world, that’s a major step toward eliminating cervical cancer as a public health threat.”
The study was supported by the National Cancer Institute.