Analysis of aberrant DNA methylation and human papillomavirus DNA in cervicovaginal specimens to detect invasive cervical cancer and its precursors.
OBJECTIVE
Cancer of the uterine cervix is an important cause of death in women worldwide. Pap smears as a tool for screening decreased the incidence and mortality of cervical cancer dramatically. This proof of principle study aimed to develop a potential tool for cervical screening using a test that can be applied by patients without visiting a physician and to increase the coverage rate, especially of the high-risk population with low socioeconomic status.


METHODS
Human papillomavirus (HPV) DNA testing and methylation analysis of DNA obtained from cervicovaginal specimens of 13, 31, and 11 patients with no dysplasia/low-grade squamous intraepithelial lesion (SIL), high-grade SIL, and invasive cervical cancer, respectively, collected on a tampon, was performed using PCR-based methods to detect invasive cervical cancer and study whether these changes are already present in the precursor lesions.


RESULTS
High-risk HPV DNA was present in 68 and 82% of patients with high-grade SIL and invasive cervical cancer. DNA methylation of the 11 genes tested increased with severity of the cervical lesion. Unsupervised hierarchical cluster analysis using solely information on DNA methylation of the 11 genes was able to predict the presence of invasive cervical cancers: one of the two clusters formed contained 9 of 11 invasive cervical cancers, as well as two high-grade SILs.


CONCLUSIONS
HPV DNA and DNA methylation analyzed in cervicovaginal specimens are able to predict invasive cervical cancers. To detect all high-grade SILs when applying this test, genes that become methylated earlier throughout cervical carcinogenesis have to be defined.
Widschwendter
Andreas
A
Department of Obstetrics and Gynecology, Innsbruck University Hospital, Innsbruck, Austria. martin.widschwendter@uibk.ac.at
Gattringer
Conny
C
Ivarsson
Lennart
L
Fiegl
Heidi
H
Schneitter
Alois
A
Ramoni
Angela
A
Müller
Hannes M
HM
Wiedemair
Annemarie
A
Jerabek
Susanne
S
Müller-Holzner
Elisabeth
E
Goebel
Georg
G
Marth
Christian
C
Widschwendter
Martin
M
D004247:DNA / Q000378:metabolism; D019175:DNA Methylation; D017931:DNA Primers / Q000737:chemistry / Q000235:genetics; D004279:DNA, Viral / Q000235:genetics*; D005260:Female; D006801:Humans; D015233:Models, Statistical; D027383:Papillomaviridae / Q000235:genetics*; D030361:Papillomavirus Infections; D016133:Polymerase Chain Reaction; D013630:Tampons, Surgical; D014412:Tumor Virus Infections; D002583:Uterine Cervical Neoplasms / Q000378:metabolism*; D014621:Vagina / Q000378:metabolism*; D002578:Uterine Cervical Dysplasia / Q000378:metabolism
D017931:DNA Primers; D004279:DNA, Viral; D004247:DNA