Aberrant promoter methylation can be useful as a marker of recurrent disease in patients with cervical intraepithelial neoplasia grade III.
BACKGROUND
Although studies of risk factor profiles have been conducted to identify biological markers to predict the natural history of cervical intraepithelial neoplasia (CIN) grade III, there is not sufficient information to support the routine clinical use of any biomarker.


OBJECTIVE
The purpose of this study was to examine aberrant promoter methylation, which is implicated in cancer development and progression, in CIN III lesions in order to identify markers associated with more aggressive biological behavior that could be used to recognize women who are at higher risk of recurrence.


METHODS
We used methylation-specific polymerase chain reaction to analyze promoter hypermethylation of 8 genes (p16, RARbeta, GSTP1, MGMT, p14, TIMP3, E-cad and DAPk) in 33 uterine cervix cones with CIN III that were also submitted to human papillomavirus (HPV) genotyping. All 33 patients in this study had been clinically followed after conization with Papanicolaou smears, colposcopy, and biopsy when indicated, every 6 months during 5 years.


RESULTS
Of the 33 patients, 12 (36%) underwent immediate hysterectomy after conization for having compromised cone margins, 14 (43%) have not relapsed, and 7 (21%) presented CIN relapse. The frequency of HPV infection in this group was 97% and no significant difference between the groups was observed. HPV of high oncogenic risk was present in 29 (87.9%) cases; HPV 16 was the most frequent (69.7%), while HPV 18 was found in 33.3%; however, it was associated with HPV 16 in 15.1%. Concomitant infection by HPV 6/11 was detected in 21.2% (15.1% with HPV 16 and 6.1 with HPV 18). 85.7% (6/7) of patients with recurrence had HPV 18 vs 0% (0/14) of patients without recurrence (P = 0.0001). At least 1 of the 8 genes was found hypermethylated in all samples. Concomitant hypermethylation of several genes was frequently found. However, CIN relapse was only seen in the cases with hypermethylation of 3 or more of the 8 genes studied (P = 0.0039).


CONCLUSIONS
We suggest that aberrant promoter methylation may play a role and may serve as a useful biomarker in the recurrence of CIN.
Terra
Ana Paula Sarreta
AP
Discipline of Special Pathology, Research Institute of Oncology, Federal University of Triângulo Mineiro, Uberaba, Brazil.
Murta
Eddie Fernando Candido
EF
Maluf
Paulo José
PJ
Caballero
Otávia Luísa Silva Damas
OL
Brait
Mariana
M
Adad
Sheila Jorge
SJ
D000328:Adult; D052685:Alphapapillomavirus / Q000302:isolation & purification*; D051017:Apoptosis Regulatory Proteins / Q000235:genetics; D014408:Biomarkers, Tumor / Q000235:genetics*; D015820:Cadherins / Q000235:genetics; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000235:genetics; D019092:Conization; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000235:genetics; D019175:DNA Methylation; D015254:DNA Modification Methylases / Q000235:genetics; D045643:DNA Repair Enzymes / Q000235:genetics; D064550:Death-Associated Protein Kinases; D018450:Disease Progression; D005260:Female; D051549:Glutathione S-Transferase pi / Q000235:genetics; D052162:Human papillomavirus 16 / Q000302:isolation & purification; D052161:Human papillomavirus 18 / Q000302:isolation & purification; D052163:Human papillomavirus 6 / Q000302:isolation & purification; D006801:Humans; D008875:Middle Aged; D030361:Papillomavirus Infections / Q000150:complications* / Q000821:virology; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic; D018168:Receptors, Retinoic Acid / Q000235:genetics; D012008:Recurrence; D019717:Tissue Inhibitor of Metalloproteinase-3 / Q000235:genetics; D025521:Tumor Suppressor Proteins / Q000235:genetics; D014412:Tumor Virus Infections / Q000150:complications; D002583:Uterine Cervical Neoplasms / Q000235:genetics* / Q000473:pathology / Q000821:virology; D002578:Uterine Cervical Dysplasia / Q000235:genetics* / Q000473:pathology / Q000821:virology
D051017:Apoptosis Regulatory Proteins; D014408:Biomarkers, Tumor; D015820:Cadherins; D019941:Cyclin-Dependent Kinase Inhibitor p16; D018168:Receptors, Retinoic Acid; C088390:TIMP3 protein, human; D019717:Tissue Inhibitor of Metalloproteinase-3; D025521:Tumor Suppressor Proteins; C082925:retinoic acid receptor beta; D015254:DNA Modification Methylases; C515491:MGMT protein, human; C496556:GSTP1 protein, human; D051549:Glutathione S-Transferase pi; D064550:Death-Associated Protein Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D045643:DNA Repair Enzymes