Abstract 3482: Directly Detect High Risk HPV Oncogenes E6/E7 mRNAs from Pap Smear Samples without RNA Purification and RT-PCR.

Abstract

Cervical cancer is one of the most common cancers in women, with about 450,000 new cases diagnosed each year. Nearly all the cervical cancers are from Papillomaviruses (HPV) infection. HPV are DNA-based viruses that infect the skin and mucous membranes of humans and many other animals. Most cancers of the vulva and vagina are induced by oncogenic HPV types. In precancerous lesions, most HPV genomes persist in an episomal state whereas, in many high-grade lesions and carcinomas, genomes are found integrated into the host chromosome. Two viral genes, E6 and E7, are invariably expressed in HPV-positive cancer cells. Their gene products are known to inactivate the major tumour suppressors, p53 and retinoblastoma protein (pRB), respectively. In addition, E6 oncoprotein is also capable to up regulate the expression of inhibitors of apoptosis, and E6 and E7 cooperate to effectively immortalise primary epithelial cells. It has been demonstrated that HPV E6/E7 expression level plays a key role in the progression of invasive carcinoma of the uterine cervix via the deregulation of cellular genes controlling tumour cell proliferation. HPV E6/E7 oncogenes have been proved to be good biological markers for prognosis assessment and specific therapy of the disease. We have developed a sandwich nucleic acid hybridization assay using branched DNA to amplify the signals. The assay can simultaneously detect E6/E7 mRNAs of all 14 high risk HPV subtypes directly from Pap smear samples without RNA purification and RT-PCR. All HPV mRNA targets are captured through cooperative hybridization of multiple probes and probe set design determines the specificity of each HPV subtype of E6/E7 mRNA. Probe set oligonucleotides bind a contiguous region of the target E6/E7 mRNAs and selectively capture target RNAs to a solid surface during hybridization. Signal amplification is performed via sequential hybridization of Pre-Amplifier, Amplifier and label probe. The assay is highly specific and sensitive, which can detect as low as 50 transcript molecules. Citation Format: Aiguo Zhang, Lulu Zhang, Rachel Chuang, Xining Zhu, Rachel Diaz, Lily Chen. Directly Detect High Risk HPV Oncogenes E6/E7 mRNAs from Pap Smear Samples without RNA Purification and RT-PCR. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3482. doi:10.1158/1538-7445.AM2013-3482