RESUMO
There is growing interest in anal cancer screening strategies. However, cytological/molecular evaluation of anal samples is challenging. We aimed to determine the feasibility of detecting, in anal liquid-based cytologies, the expression of biomarkers involved in the cell cycle disturbance elicited by human papillomavirus (HPV). The accuracy of this approach in the identification of high-grade squamous intraepithelial lesions/anal intraepithelial neoplasia grade2-3 (HSIL/AIN2-3) was also evaluated. 215 anal cytologies from men having sex with men living with human immunodeficiency virus were evaluated. Patients showing concordant cytological and anoscopy-directed biopsy diagnosis were selected: 70 with negative cytology and HPV test, 70 with low-grade SIL (LSIL/AIN1) cytology and biopsy, and 75 with cytology and biopsy of HSIL/AIN2-3. CDKN2A/p16, MKI67 and TOP2A mRNA expression was analyzed. HPV detection was performed with Xpert HPV Assay (Cepheid, Sunnyvale, CA, USA). HSIL/AIN2-3 showed higher expression for the biomarkers than LSIL/AIN1 or negative samples. The specificity for HSIL/AIN2-3 detection for a sensitivity established at 70% was 44.7% (95%confidence interval [CI] 36.5-53.2) for TOP2A and MKI67 and 54.5% (95%CI 46.0-62.8%) for CDKN2A/p16. mRNA detection of cell biomarkers in anal liquid-based cytology is feasible. Further studies are warranted to confirm if strategies based on mRNA detection have any role in anal cancer screening.
RESUMO
Several high-risk human papillomavirus (HPV)-induced cell biomarkers have been proposed as possible candidates to identify patients harboring high-grade squamous intraepithelial lesions (HSILs) of the uterine cervix. We aimed to determine the feasibility of the detection of the mRNA of six biomarkers in cervical smear specimens obtained by liquid-based cytology and to evaluate whether this approach might be useful in the identification of patients with HSIL. One-hundred and twenty three women referred to colposcopy in the Hospital Clinic of Barcelona were included in the study. After a thorough study, including Pap test, high-risk HPV testing (Hybrid Capture 2 test), and colposcopy with directed biopsy and/or endocervical curettage, 48 patients were diagnosed with HSIL, whereas 75 were classified as negative (n=28), or harboring low-grade SIL (n=47). CDKN2A/p16, BIRC5, MMP9, TOP2A, MCM5, and MKI67 mRNA expression was analyzed by reverse transcription quantitative polymerase chain reaction in liquid-based cytology after the Pap test and Hybrid Capture 2 performance. The tissue expression of these biomarkers was analyzed by immunohistochemistry in the biopsy material. One-hundred and thirteen out of 123 (92%) liquid-based cytology yielded adequate material for mRNA analysis. TOP2A was the most sensitive (97%) biomarker for the detection of HSIL and CDKN2A/p16 the most specific (78%). The combination of TOP2A and CDKN2A/p16 showed a sensitivity of 96% (95% confidence interval (CI): 88-99) and a specificity of 71% (95% CI: 55-82). In the immunohistochemistry analysis, all biomarkers showed a high sensitivity but low specificity for HSIL, except CDKN2A/p16 which had a sensitivity of 100% and a specificity of 63%. The combination of TOP2A and CDKN2A/p16 showed a sensitivity of 100% (95% CI: 91-100) and a specificity of 43% (95% CI: 32-55). The detection of mRNA of cell biomarkers in liquid-based cytology material is feasible. The combination TOP2A and CDKN2A/p16 has a good balance between sensitivity and specificity for the detection of women with HSIL.