STUDY QUESTION Can we reconstitute physiologically relevant 3-dimensional (3D) microengineered endometrium in-vitro model? SUMMARY ANSWER Our representative microengineered vascularised endometrium on-a-chip closely recapitulates the endometrial microenvironment that consists of three distinct layers including epithelial cells, stromal fibroblasts and endothelial cells in a 3D extracellular matrix in a spatiotemporal manner. WHAT IS KNOWN ALREADY Organ-on-a-chip, a multi-channel 3D microfluidic cell culture system, is widely used to investigate physiologically relevant responses of organ systems. STUDY DESIGN, SIZE, DURATION The device consists of five microchannels that are arrayed in parallel and partitioned by array of micropost. Two central channels are for 3D culture and morphogenesis of stromal fibroblast and endothelial cells. In addition, the outermost channel is for the culture of additional endometrial stromal fibroblasts that secrete biochemical cues to induce directional pro-angiogenic responses of endothelial cells. To seed endometrial epithelial cells, on Day 8, Ishikawa cells were introduced to one of the two medium channels to adhere on the gel surface. After that, the microengineered endometrium was cultured for an additional 5–6 days (total ∼ 14 days) for the purpose of each experiment. PARTICIPANTS/MATERIALS, SETTING, METHODS Microfluidic 3D cultures were maintained in endothelial growth Medium 2 with or without oestradiol and progesterone. Some cultures additionally received exogenous pro-angiogenic factors. For the three distinct layers of microengineered endometrium-on-a-chip, the epithelium, stroma and blood vessel characteristics and drug response of each distinct layer in the microfluidic model were assessed morphologically and biochemically. The quantitative measurement of endometrial drug delivery was evaluated by the permeability coefficients. MAIN RESULTS AND THE ROLE OF CHANCE We established microengineered vascularised endometrium-on-chip, which consists of three distinct layers: epithelium, stroma and blood vessels. Our endometrium model faithfully recapitulates in-vivo endometrial vasculo-angiogenesis and hormonal responses displaying key features of the proliferative and secretory phases of the menstrual cycle. Furthermore, the effect of the emergency contraception drug levonorgestrel was evaluated in our model demonstrating increased endometrial permeability and blood vessel regression in a dose-dependent manner. We finally provided a proof of concept of the multi-layered endometrium model for embryo implantation, which aids a better understanding of the molecular and cellular mechanisms underlying this process. LARGE SCALE DATA N/A. LIMITATIONS, REASONS FOR CAUTION This report is largely an in-vitro study and it would be beneficial to validate our findings using human primary endometrial cells. WIDER IMPLICATIONS OF THE FINDINGS Our 3D microengineered vascularised endometrium-on-a-chip provides a new in-vitro approach to drug screening and drug discovery by mimicking the complicated behaviours of human endometrium. Thus, we suggest our model as a tool for addressing critical challenges and unsolved problems in female diseases, such as endometriosis, uterine cancer and female infertility, in a personalised manner. STUDY FUNDING/COMPETING INTEREST(S) This work is supported by funding from the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) to Y.J.K. (No. 2018R1C1B6003), to J.A. (No. 2020R1I1A1A01074136) and to H.S.K. (No. 2020R1C1C100787212). The authors report no conflicts of interest.

Successful pregnancy inevitably depends on the implantation of a competent embryo into a receptive endometrium. Although many substances have been suggested to improve the rate of embryo implantation targeting enhancement of endometrial receptivity, currently there rarely are effective evidence-based treatments to prevent or cure this condition. Here we strongly suggest minimally-invasive intra-uterine administration of embryo-secreted chemokine CXCL12 as an effective therapeutic intervention. Chemokine CXCL12 derived from pre- and peri-implanting embryos significantly enhances the rates of embryo attachment and promoted endothelial vessel formation and sprouting in vitro. Consistently, intra-uterine CXCL12 administration in C57BL/6 mice improved endometrial receptivity showing increased integrin β3 and its ligand osteopontin, and induced endometrial angiogenesis displaying increased numbers of vessel formation near the lining of endometrial epithelial layer with higher CD31 and CD34 expression. Furthermore, intra-uterine CXCL12 application dramatically promoted the rates of embryo implantation with no morphologically retarded embryos. Thus, our present study provides a novel evidence that improved uterine endometrial receptivity and enhanced angiogenesis induced by embryo-derived chemokine CXCL12 may aid to develop a minimally-invasive therapeutic strategy for clinical treatment or supplement for the patients with repeated implantation failure with less risk.

To investigate the therapeutic efficacy of hyperthermic intraperitoneal chemotherapy (HIPEC) as consolidation treatment after completing first-line treatment in patients with advanced ovarian cancer. MethodsA retrospective chart review was conducted on patients treated at the Comprehensive Gynecologic Cancer Center between January 2014 and 2019. Based on the inclusion criteria, 24 eligible patients who received HIPEC (paclitaxel 175 mg/m 2 , for 90 min, at 42°C) (HIPEC group) as consolidation treatment after terminating the adjuvant chemotherapy were identified. Another 24 patients who met the inclusion criteria and did not receive HIPEC were matched, representing the non-HIPEC group. Disease-free survival (DFS) and overall survival (OS) were examined between the two groups. ResultsThe median DFS was 28.7 and 24.2 months in the HIPEC and non-HIPEC groups, respectively (P=0.688). The 3year DFS rates in the HIPEC and non-HPEC groups were 39.5% and 32.6%, respectively. However, the median OS was not determined. The 5-year OS rates in the HIPEC and non-HIPEC groups were 86.2% and 81.3%, respectively (P=0.850). One patient developed grade 3 neutropenia. Other patients experienced mild adverse events after HIPEC. ConclusionThis study suggests that consolidation HIPEC could not support the survival benefit after completing the first-line treatment for patients with advanced ovarian cancer, although no severe specific safety issues were found. Therefore, randomized trials evaluating consolidation HIPEC for the management of ovarian cancer are warranted.

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