Human papillomavirus DNA and host gene mRNA biomarker detection in a "micro total analysis aystem" (microTAS) device to aid diagnosis of cervical intraepithelial neoplasia
Background: Human papillomavirus (HPV) DNA detection has high sensitivity for high-grade cervical intraepithelial neoplasia (CIN), but low specificity. Cervical cancer research is focused on development of biomarkers (BM) for prediction of disease severity eg. HPV E6/E7mRNA and p16INK4a/Ki67. This study describes a novel set of host mRNA biomarkers, mediator probe PCR (MP-PCR), and microTAS device for HPV DNA and BM detection in LBC. Design: A panel of 21 BM were validated by TaqMan PCR assays on 692 women with known histology and HPV status (Hybrid Capture 2 (HC2) and Linear Array HPV Genotyping (LA-HPV)) recruited from colposcopy clinics through CERVIVA (The Irish Cervical Screening Research Consortium) and Jedlik Anyos HPV Screen Multicentric Clinical Study, Hungary. A novel MP-PCR test was designed for HPV and BM detection, clinically validated on AB7900 thermal cycler and miniaturised for use in a microfluidic chip run on an instrument designed for multichannel thermal cycling and fluorophore detection (microTAS device). Results: Combined BM and HPV testing by TaqMan and hc2 had high specificity (91%), and sensitivity (75%) for CIN1+. HPV16 MP-PCR on AB7900 had high positive predictive value (95%), comparable to HC2 (94%) for CIN2+. On the microTAS device, the HPV16 MP-PCR had a limit of detection of 160 HPV16 copies with high sensitivity (85%) and concordance (82%) to LA-HPV for HPV16 detection. Concordance of TaqMan PCR and the microTAS device for 4 of the mRNA BM ranged from 79% to 83.3%. Conclusions: Combined mRNA BM and HPV DNA detection by PCR methods may be a useful alternative to consecutive BM and HPV, can be readily adapted for microTAS and should be explored further.