title: [Viral load, genomic integration frequency of human papillomavirus 16 in cervical cancer and precancerous lesions].
abstract: OBJECTIVE
  To investigate the association between viral load, genomic integration frequency of HPV 16 and cervical carcinogenesis and assess the probability that HPV 16 integration frequency may be utilized as a marker for cervical cancer.
  
  
  METHODS
  Forty cases of HPV16 single infection were selected from 337 cervical scrape samples by PCR (polymerase chain reaction) amplification and DNA sequencing. The copy numbers of E2, E6 and β-actin were quantified to evaluate the viral load and integration status by real-time PCR.
  
  
  RESULTS
  (1) The median number of adjusted viral load of normal group, LSIL (low-grade squamous intraepithelial lesion) group, HSIL (high-grade squamous intraepithelial lesion) group and squamous cervical cancer group were 0.11, 18.55, 44.63 and 7.6 copies per cell respectively. The viral load was higher in LSIL-HSIL group than that in normal group while lower in squamous cervical cancer group than that in HSIL group. (2) The median number of E2/E6 was 0.93 in normal group, 0.84 in precancerous group (LSIL-HSIL) and 0.64 in squamous cervical cancer group respectively. It showed a descending trend with the progression of cervical disease. (3) With the disease development, the proportion of episomal form decreased (normal group 4/5, LSIL group 4/6, HSIL group 10/16, cervical squamous cancer group 5/13) whereas that of integrated form (mixed and totally integrated) increased (normal group 1/5, LSIL group 2/6, HSIL group 6/16, cervical squamous cancer group 8/13). Both totally integrated cases were cervical squamous cancer.
  
  
  CONCLUSIONS
  (1) HPV 16 viral load may not be an ideal marker to predict cervical carcinogenesis. (2) Due to a positive correlation between HPV16 genomic integration frequency and cervical neoplastic progression, HPV 16 integration frequency may be a potential marker of early diagnosis for cervical lesion progression.
authors: Department of Obstetrics & Gynecology, Chinese Academy of Medical Sciences, Beijing 100730, China.
authors: Yuan
authors: Y
authors: Li
authors: Yang
authors: Y
authors: Xiang
authors: Rui-fen
authors: RF
authors: Zhang
authors: Yu-pin
authors: YP
authors: Cai
authors: Yi
authors: Y
authors: Yang
authors: Xue-mei
authors: XM
authors: Cheng
authors: Bao-li
authors: BL
authors: Zhu