Tissue remodeling of human endometrium occurs during the menstrual cycle to prepare for embryo adhesion and invasion. The ovarian steroid hormones 17β-estradiol and progesterone control the menstrual cycle to achieve the receptive state during the “window of implantation” (WOI). Here, we focus on the human endometrial epithelium and its changes in polarity, adhesion, cytoskeletal organization and the underlying extracellular matrix enabling embryo implantation. The adhesion and invasion of the trophoblast via the apical plasma membrane of epithelial cells is a unique cell biological process, which is coupled to partial epithelial–mesenchymal transition (EMT). Given the fundamental species differences during implantation, we restrict the review mainly to the human situation and focus on cell culture systems to study the interaction between human trophoblast and endometrial cells. We summarize current knowledge based on the relatively scarce in vivo data and the steadily growing in vitro observations using various cell culture systems.

Angiogenesis - the formation of new blood vessels from pre-existing ones - is one of the hallmarks of cancer, regardless of subtype. However, the development of a specific tumor type is a highly heterogeneous process that influences the morphology of the tumor vasculature, which has a direct impact on the malignancy and invasiveness of the lesions. Therefore, the analysis of tumor vascularity without the need for invasive procedures is of fundamental interest for the classification of tumor tissue and the monitoring of therapies. Ultrasound localization microscopy is a promising new technique that breaks the resolution limits of conventional ultrasound imaging and allows to detect vascular structures and blood flow down to the capillary level. In this article, we discuss this emerging technique in the context of cancer imaging, focusing on crucial implementation aspects as well as on initial basic research in preclinical and clinical settings.

This study aimed to assess the association of CA125 levels at pre-defined clinical time points with survival outcomes and to evaluate its role in recurrence detection in low-grade serous ovarian cancer. In this retrospective multi-center cohort study, patients with low-grade serous ovarian cancer of all International Federation of Gynecology and Obstetrics stages treated between 2007 and 2023 at 9 tertiary centers in Germany and Austria were included. Clinical data and serial CA125 measurements were extracted from medical records at pre-defined time points: diagnosis, after debulking surgery, during adjuvant therapy, follow-up, and recurrence. Associations with progression-free survival and overall survival were analyzed using Kaplan-Meier estimates and Cox regression. Sensitivity of CA125 for recurrence detection was assessed. A total of 368 patients were included; 84.2% had International Federation of Gynecology and Obstetrics stage IIB to IV disease. Median baseline CA125 was 113 U/mL, declining to 16 U/mL after primary treatment and remaining below 35 U/mL during follow-up. A 10-fold increase in baseline CA125 was associated with worse overall survival (hazard ratio 2.24, 95% confidence interval 1.37 to 3.67), remaining significant after adjustment for International Federation of Gynecology and Obstetrics stage, residual disease, age, and ascites (hazard ratio 1.90; 95% confidence interval 1.13 to 3.19). Elevated post-operative CA125 was associated with shorter progression-free survival. Persistently elevated CA125 after 6 cycles of adjuvant chemotherapy was associated with a higher hazard of progression or death (hazard ratio 5.54; 95% confidence interval 2.21 to 13.9). At recurrence, CA125 detected most relapses; however, 15.7% occurred despite normal marker levels, corresponding to a sensitivity of 84% (95% CI 74.0 to 90.4). CA125 in low-grade serous ovarian cancer correlates with disease stage, reflects treatment response, and shows prognostic relevance for progression-free survival at pre-defined clinical time points. It may support recurrence detection but should not be used as a stand-alone marker.