Background: Vulvar cancer mainly affects postmenopausal women, but its incidence is rising among younger individuals due to persistent HPV infection. Validated diagnostic biomarkers remain lacking, though circulating exosomal microRNAs (exomiRs) have recently emerged as promising liquid biopsy tools across various cancers. Objective: The purpose of this study was to identify a panel of dysregulated plasma-derived extracellular vesicle (EV)-associated miRNAs, hereafter referred to as exosomal micro-RNAs, as liquid biopsy markers for the detection of vulvar cancer and for assessment of HPV-positivity. Methods: Five healthy donor (HD) and 10 vulvar cancer samples underwent Next-Generation Sequencing to screen for differentially expressed exomiRs. The seven most dysregulated and four stably expressed exomiRs were subsequently analyzed in 81 cancer and 60 HD samples by qRT-PCR. Differential expression was determined by the 2−ΔΔCT method. Binary regression was used to construct an exomiR panel. HPV status was assessed using mass spectrometry. Results: Five single exomiRs showed a statistically significant dysregulation in cancer patients compared to healthy controls: miR-143-3p, miR-223-3p, miR-451a, miR-4516 and miR-151a-5p. The combination of six exomiRs resulted in a panel with superior diagnostic ability (p < 0.001; ROC-AUC = 0.805; 95% CI: 0.726–0.884) in distinguishing cancer patients from HDs. A model consisting of miR-223-3p, miR-143-3p and miR-451a could discriminate HPV-positive from -negative (p = 0.003; ROC-AUC = 0.939), and a model of miR-4516, miR-143-3p, miR-16-5p and miR-451a was predictive of lymph node positivity (p < 0.001, ROC-AUC = 0.786). Multivariate Cox regression showed that a model of downregulated miR-16-5p and upregulated miR-451a was significantly associated with poorer survival (p = 0.023). Conclusions: This study indicates the future potential of exomiRs as diagnostic and prognostic liquid biopsy markers for vulvar cancer.
Borchardt et al. (Thu,) studied this question.