Diagnostic value of endometrial cytology and related technology

FBXO7, a tumor suppressor in endometrial carcinoma, suppresses INF2-associated mitochondrial division

Endometrial carcinoma (ECa) is the most common malignant gynecological cancer, with an increased incidence and fatality rate worldwide, while the pathogenesis is still largely unknown. In this study, we confirmed that FBXO7, a gene coding FBXO7 E3 ubiquitin ligase, is significantly downregulated and mutated (5.87%; 31/528) in ECa specimens, and the abnormal low expression and mutations of FBXO7 are associated with the occurrence of ECa. We also identify the excessive expression of INF2 protein, a key factor that triggers mitochondrial division by recruiting the DRP1 protein, and the elevated INF2 protein is significantly negatively correlated with the low FBXO7 protein in ECa specimens. Mechanistically, FBXO7 restrains ECa through inhibiting INF2-associated mitochondrial division via FBXO7-mediated ubiquitination and degradation of INF2. Moreover, we found that ECa-associated FBXO7 mutants are defective in the ubiquitination and degradation of INF2, promoting ECa cells proliferation, migration and apoptosis inhibition via inducing mitochondrial hyper-division. In addition, we found that it could reverse FBXO7 deletion or ECa-associated FBXO7 mutants-induced proliferation, migration, apoptosis inhibition and mitochondrial hyper-division of ECa cells by INF2 or DNM1L knockdown, or DRP1 inhibitor Mdivi-1. In summary, our study shows that FBXO7 acts as a novel tumor suppressor in ECa by inhibiting INF2-DRP1 axis-associated mitochondrial division through the ubiquitination and degradation of INF2 while the effect is destroyed by ECa-associated FBXO7 and INF2 mutants, highlights the key role of FBXO7-INF2-DRP1 axis in ECa tumorigenesis and provides a new viewpoint to treat ECa patients with FBXO7 deletion or mutations by targeting INF2-DRP1 axis-associated mitochondrial division.

Endometrial Cytology in Diagnosis of Endometrial Cancer: A Systematic Review and Meta-Analysis of Diagnostic Accuracy

BACKGROUND

Because the incidence of endometrial cancer has been increasing every year, it is important to identify an effective screening method for it. The endometrial cytology test (ECT) is considered to be the more acceptable technique compared to invasive endometrial sampling.

METHODS

The study followed the Priority Reporting Project for Systematic Evaluation and Meta-Analysis (PRISMA-DTA) protocol. This systematic rating searched EMBASE and Web of Science databases for studies on ECT for endometrial cancer from the databases' dates of inception to 30 September 2022. All literature screening and data extraction were performed by two researchers, while the methodological quality of the included studies was assessed against defined inclusion criteria. And a third researcher resolves the disagreements.

RESULTS

Twenty-six studies were eventually included in this final analysis. Meta-analysis results showed that the diagnostic accuracy characteristics of ECT for endometrial cancer were as follows: combined sensitivity = 0.84 [95% confidence interval (CI) (0.83-0.86)], combined specificity = 0.98 [95% CI (0.98-0.98)], combined positive likelihood ratio = 34.65 [95% CI (20.90-57.45)], combined negative likelihood ratio = 0.21 [95% CI (0.15-0.30)], and area under the summary receiver operating characteristic curve = 0.9673.

CONCLUSIONS

ECT had the ability to detect endometrial cancer with strong specificity, although some studies have demonstrated significant differences in sensitivity.