PAX1 Methylation Status in Cervical Scrapes as Novel Diagnostic Biomarker in CIN 2/3 and Invasive Squamous Cell Carcinoma.

OBJECTIVES: DNA methylation of paired box-1 (PAX-1) gene has been shown to be a potential biomarker for the detection of high-grade cervical intra-epithelial neoplasia (CIN) and invasive cervical cancer. The objective of this pilot study was to quantify and compare methylation percentage of PAX1 gene in benign cervical lesion, pre-invasive and invasive cervical cancer.

METHODS: A total of 200 screen positive women (VIA, VILI and Pap test) underwent colposcopy. Cervical scrapes taken were taken and stored for DNA analysis and PAX 1 methylation status. Women with Swede score of 5 or more ( n  = 98) were biopsied. Cervical scrapes and biopsy were taken from women with obvious cervical growth ( n  = 14), without prior colposcopy. Sixty women were recruited to the study and allocated into three groups on the basis of histopathology, i.e., benign cervix (Group 1; n  = 20), CIN 2/3 (Group 2; n  = 20) and invasive cervical carcinoma (Group; n  = 20). PAX 1 methylation percentage was calculated from the DNA extracted from the cervical scrapes of the women recruited.

RESULTS: The mean PAX1 methylation percentage in benign lesions, CIN 2/3 and invasive cancer was 9.58% (SD ± 2.37%), 18.21% (SD ± 2.67%) and 24.34% (SD ± 4.09%), respectively, with p-value of < 0.001.

CONCLUSIONS: PAX 1 gene methylation has a promising role in identifying high-grade lesions and invasive cancer.