Open AccessRapid and ultrasensitive detection of circulating human papillomavirus E7 cell-free DNA as a cervical cancer biomarker
Author(s) -
Phetploy Rungkamoltip,
Sasithon Temisak,
Kitiya Piboonprai,
Deanpen Japrung,
Pattanapong Thangsunan,
Saranya Chanpanitkitchot,
Woraphot Chaowawanit,
Nutthaporn Chandeying,
Siriwan Tangjitgamol,
Tawin Iempridee
Publication year - 2020
Publication title -
experimental biology and medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.012
H-Index - 146
eISSN - 1535-3702
pISSN - 1535-3699
DOI - 10.1177/1535370220978899
Subject(s) - recombinase polymerase amplification , biomarker , cervical intraepithelial neoplasia , cervical cancer , digital polymerase chain reaction , cell free fetal dna , cancer , cancer research , medicine , real time polymerase chain reaction , cancer biomarkers , papillomaviridae , polymerase chain reaction , oncology , microbiology and biotechnology , biology , gene , genetics , pregnancy , fetus , prenatal diagnosis
Circulating cell-free DNA (cfDNA) has attracted attention as a non-invasive biomarker for diagnosing and monitoring various cancers. Given that human papillomavirus (HPV) DNA integration and overexpression of E6/E7 oncogenes are pivotal events for carcinogenesis, we sought to determine if HPV E7 cfDNA could serve as a specific biomarker for cervical cancer detection. We applied droplet digital PCR (ddPCR) to quantify HPV16/18 E7 cfDNA from the serum of patients with cervical cancer, cervical intraepithelial neoplasia, and controls. HPV16/18 E7 cfDNA was highly specific for cervical cancer, displaying 30.77% sensitivity, 100% specificity, and an area under the curve of 0.65. Furthermore, we developed a sensitive isothermal detection of HPV16/18 E7 and the PIK3CA WT reference gene based on recombinase polymerase amplification combined with a lateral flow strip (RPA-LF). The assay took less than 30 min and the detection limit was 5-10 copies. RPA-LF exhibited 100% sensitivity and 88.24% specificity towards HPV16/18 E7 cfDNA in clinical samples. The agreement between RPA-LF and ddPCR was 83.33% ( κ = 0.67) for HPV16 E7 and 100% ( κ = 1.0) for HPV18 E7, indicating a good correlation between both tests. Therefore, we conclude that HPV E7 cfDNA represents a potential tumor marker with excellent specificity and moderate sensitivity for minimally invasive cervical cancer monitoring. Moreover, the RPA-LF assay provides an affordable, rapid, and ultrasensitive tool for detecting HPV cfDNA in resource-limited settings.