CyclinA1 Promoter Methylation in Self-Sampling Test

Efficiency of CIN2+ Detection by Thyrotropin-Releasing Hormone (TRH) Site-Specific Methylation

Cervical cancer screening typically involves a Pap smear combined with high-risk human papillomavirus (hr-HPV) detection. Women with hr-HPV positivity but normal cytology, as well as those with precancerous abnormal cytology, such as low-grade squamous intraepithelial lesions (LSIL) and high-grade SIL (HSIL), are referred for colposcopy and histology examination to identify abnormal lesions, such as cervical intraepithelial neoplasia (CIN) and cervical cancer. However, in order to enhance the accuracy of detection, bioinformatics analysis of a microarray database was performed, which identified cg01009664, a methylation marker of the thyrotropin-releasing hormone (TRH). Consequently, a real-time PCR assay was developed to distinguish CIN2+ (CIN2, CIN3, and cervical cancer) from CIN2- (CIN1 and normal cervical epithelia). The real-time PCR assay utilized specific primers targeting methylated cg01009664 sites, whereas an unmethylated reaction was used to check the DNA quality. A cut-off value for the methylated reaction of Ct < 33 was established, resulting in improved precision in identifying CIN2+. In the first cohort group, the assay demonstrated a sensitivity of 93.7% and a specificity of 98.6%. In the cytology samples identified as atypical squamous cells of undetermined significance (ASC-US) and LSIL, the sensitivity and specificity for detecting CIN2+ were 95.0% and 98.9%, respectively. However, when self-collected samples from women with confirmed histology were tested, the sensitivity for CIN2+ detection dropped to 49.15%, while maintaining a specificity of 100%. Notably, the use of clinician-collected samples increased the sensitivity of TRH methylation testing. TRH methylation analysis can effectively identify women who require referral for colposcopy examinations, aiding in the detection of CIN2+.

Worldwide initiatives to eliminate cervical cancer

In 2020, more than 600 000 women were diagnosed with cervical cancer and 342 000 women died worldwide. Without comprehensive control, rates of cervical cancer incidence and mortality are expected to worsen. In 2020, the World Health Organization adopted the global strategy to eliminate cervical cancer to the threshold of four cases per 100 000 women within the 21st century, using a triple pillar intervention strategy comprising 90% of girls fully vaccinated by the age of 15 years, 70% of women screened by the age of 35 years and again by 45 years, and 90% of women with precancer treated and 90% of women with invasive cancer managed. In countries with high cervical cancer incidence, a tremendous effort will be needed to overcome the challenges. This article discusses the efforts in place to accelerate achievement of this ambitious goal.

A triple pillar intervention strategy of vaccination, screening, and timely treatment has been adopted to guide the global ambition to eliminate cervical cancer.