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- DNA methylation as a triage marker for colposcopy referral in HPV-based cervical cancer screening: a systematic review and meta-analysisPublication . Salta, Sofia; Lobo, João; Magalhães, Bruno; Henrique, Rui; Jerónimo, CarmenScreening plays a key role in secondary prevention of cervical cancer. High-risk human papillomavirus (hrHPV) testing, a highly sensitive test but with limited specificity, has become the gold standard frontline for screening programs. Thus, the importance of effective triage strategies, including DNA methylation markers, has been emphasized. Despite the potential reported in individual studies, methylation markers still require validation before being recommended for clinical practice. This systematic review and meta-analysis aimed to evaluate the performance of DNA methylation-based biomarkers for detecting high-grade intraepithelial lesions (HSIL) in hrHPV-positive women. Hence, PubMed, Scopus, and Cochrane databases were searched for studies that assessed methylation in hrHPV-positive women in cervical scrapes. Histologically confirmed HSIL was used as endpoint and QUADAS-2 tool enabled assessment of study quality. A bivariate random-effect model was employed to pool the estimated sensitivity and specificity as well as positive (PPV) and negative (NPV) predictive values. Twenty-three studies were included in this meta-analysis, from which cohort and referral population-based studies corresponded to nearly 65%. Most of the women analyzed were Dutch, and CADM1, FAM19A4, MAL, and miR124-2 were the most studied genes. Pooled sensitivity and specificity were 0.68 (CI 95% 0.63–0.72) and 0.75 (CI 95% 0.71–0.80) for cervical intraepithelial neoplasia (CIN) 2+ detection, respectively. For CIN3+ detection, pooled sensitivity and specificity were 0.78 (CI 95% 0.74–0.82) and 0.74 (CI 95% 0.69–0.78), respectively. For pooled prevalence, PPV for CIN2+ and CIN3+ detection were 0.514 and 0.392, respectively. Furthermore, NPV for CIN2+ and CIN3+ detection were 0.857 and 0.938, respectively. This meta-analysis confirmed the great potential of DNA methylation-based biomarkers as triage tool for hrHPV-positive women in cervical cancer screening. Standardization and improved validation are, however, required. Nevertheless, these markers might represent an excellent alternative to cytology and genotyping for colposcopy referral of hrHPV-positive women, allowing for more cost-effective screening programs.
- Methamphetamine promotes a-tubulin deacetylation in endothelial cells: The protective role of acetyl-L-carnitinePublication . Fernandes, Sílvia; Salta, Sofia; Summavielle, TeresaMethamphetamine (METH) is a powerful psychostimulant drug used worldwide for its reinforcing properties. In addition to the classic long-lasting monoaminergic-disrupting effects extensively described in the literature, METH has been consistently reported to increase blood brain barrier (BBB) permeability, both in vivo and in vitro, as a result of tight junction and cytoskeleton disarrangement. Microtubules play a critical role in cell stability, which relies on post-translational modifications such as a-tubulin acetylation. As there is evidence that psychostimulants drugs modulate the expression of histone deacetylases (HDACs), we hypothesized that in endothelial cells METH-mediation of cytoplasmatic HDAC6 activity could affect tubulin acetylation and further contribute to BBB dysfunction. To validate our hypothesis, we exposed the bEnd.3 endothelial cells to increasing doses of METH and verified that itleads to an extensivea-tubulin deacetylation mediated by HDACs activation. Furthermore, since we recently reported that acetyl-L-carnitine (ALC), a natural occurring compound, prevents BBB structural loss in a context of METH exposure, we reasoned that ALC could also preserve the acetylation of microtubules under METH action. The present results confirm that ALC is able to prevent METH-induced deacetylation providing effective protection on microtubule acetylation. Although further investigation is still needed, HDACs regulation may become a new therapeutic target for ALC.