Micronucleus cytome assay reveals genomic instability in premalignant cervical lesions among high-risk HPV-positive women

Cervical cancer is a major health burden driven by persistent infection with high-risk human papillomavirus (HPV). Genomic instability biomarkers from the micronucleus cytome (MNcyt) assay may improve identification of women at risk of progression beyond cytology and HPV testing. A cross-sectional study of 184 women attending routine cervical cancer screening was conducted in Popayán, Colombia. Exfoliated cervical epithelial cells were collected for HPV DNA genotyping, liquid-based cytology, and MNcyt analysis using the Feulgen-Fast Green DNA-specific method. For each sample, 2,000 cells were scored for micronuclei, nuclear buds, binucleated cells, pyknotic cells, karyorrhectic cells, karyolytic cells, and cells with condensed chromatin. Group differences and trends were assessed across ordered HPV/cytology categories; genotype analyses used age-adjusted models and, among HPV-positive women, models adjusted for age and cytology. Women were classified as HPV-negative with negative for intraepithelial lesion or malignancy (HPV−/NILM, n = 69), HPV-positive with NILM (HPV+/NILM, n = 47), HPV-positive with atypical squamous cells of undetermined significance or low-grade squamous intraepithelial lesion (HPV+/ASCUS-LSIL, n = 49), and HPV-positive with high-grade squamous intraepithelial lesion or worse (HPV+/≥HSIL, n = 19). Significant positive trends across these ordered categories were observed for micronuclei (p = 0.044), nuclear buds (p = 0.029), and binucleated cells (p = 0.011). Among HPV-positive women, genotype differences adjusted for age and cytology were observed for nuclear buds (p = 0.046), karyolytic cells (p = 0.010), and condensed chromatin (p = 0.035). Overall, micronuclei, nuclear buds, and binucleated cells showed consistent patterns of genomic instability across HPV/cytology categories, while genotype-focused analyses also identified differences in selected genotoxic and cytotoxic endpoints. These findings support the potential value of MNcyt biomarkers as a complementary approach for risk assessment in HPV-related cervical disease.