Diagnostic performance of HPV E6/E7, hTERT, and Ki67 mRNA RT-qPCR assays on formalin-fixed paraffin-embedded cervical tissue specimens from women with cervical cancer

Exp Mol Pathol. 2015 Jun;98(3):510-6. doi: 10.1016/j.yexmp.2015.03.036. Epub 2015 Mar 31.

Abstract

Human papillomavirus (HPV) is a major cause of cervical cancer, which is the third most common cancer in women. Human telomerase reverse transcriptase (hTERT) and Ki67 are tumor cell markers indicating cancer cell proliferation in cancer patients, and activation of hTERT and Ki67 leads to progressive cervical carcinogenesis. In the present study, we evaluated the CervicGen HPVE6/E7 mRNA RT-qDx assay, which detects 16 HPV high-risk (HR) genotypes (HPV 16, 18, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, 68 and 69), and the CervicGen hTERT and Ki67 mRNA RT-qDx assay using 117 formalin-fixed paraffin-embedded (FFPE) cervical cancer tissue samples. The diagnostic validity of the CervicGen HPV RT-qDx assay for detecting histologically proven prevalent squamous cell carcinoma (SCC) was 94% sensitivity, 100% specificity, 77.8% positive predictive value (PPV), and 78.9% negative predictive value (NPV). The most common HPV genotypes detected in FFPE cervical cancer tissue samples were HPV 16 (56%) and HPV 18 (10%). The positivity rate of hTERT and Ki67 mRNA expressions in FFPE cervical cancer tissue samples on RT-qPCR was 65% and 93% respectively. Moreover, the positivity rates were 92% for a combination of HPV E6/E7 and hTERT mRNA expressions, 97% for HPV E6/E7 and Ki67 mRNA expressions, and 99% (99/100) for the combination of HPV E6/E7, hTERT, and Ki67 mRNA expressions. These data showed that SSC FFPE cervical cancer tissue samples correlated more strongly with high Ki67 mRNA expressions than with hTERT mRNA expressions. Notably, hTERT and Ki67 mRNA expression level was increased in high-grade cervical lesions, but was very low in normal samples. Our findings suggest that the combination of HPV E6/E7, hTERT, and Ki67 mRNA expression levels could be used in a complementary manner in diagnosing high-grade cervical lesions. Further studies are required to evaluate these assays as a useful predictive tool for screening low-grade cervical lesions.

Keywords: Cervical cancer; E6/E7 mRNA; FFPE; HPV; Ki67; Molecular diagnosis; RT-qPCR; hTERT.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Female
  • Human Papillomavirus DNA Tests / methods*
  • Humans
  • Ki-67 Antigen / genetics
  • Ki-67 Antigen / metabolism*
  • Oncogene Proteins, Viral / genetics
  • Oncogene Proteins, Viral / metabolism*
  • Paraffin Embedding / methods*
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Real-Time Polymerase Chain Reaction / methods*
  • Sensitivity and Specificity
  • Telomerase / genetics
  • Telomerase / metabolism*
  • Tissue Fixation / methods
  • Uterine Cervical Neoplasms / diagnosis*
  • Uterine Cervical Neoplasms / metabolism

Substances

  • Ki-67 Antigen
  • Oncogene Proteins, Viral
  • RNA, Messenger
  • TERT protein, human
  • Telomerase