The purpose of this study was to establish tumor tissue specific delivery of let-7i miRNA to reverse paclitaxel-induced chemoresistance. A chimera that combines MUC1 aptamer and let-7i miRNA was tested in OVCAR-3 ovarian cancer cells. Results demonstrated that the chimera can specifically be delivered into OVCAR-3 cells and the released let-7i significantly sensitized the role of paclitaxel in inhibiting cell proliferation, inducing cell apoptosis, and decreasing long-term cell survival. The chimera achieved reversal of chemoresistance through downregulation of cyclin D1, cyclin D2, Dicer 1, and PGRMC1 expressions. Our study indicated that this MUC1/let-7i chimera can specifically reverse chemoresistance to paclitaxel.

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Recently, perinatal outcomes and cumulative live birth rate (cLBR) have widely been utilized to assess the fertility outcomes and safety of assisted reproductive technology (ARt), but more robust research is needed to address the success rates of live-healthy births resulting from this procedure, particularly for patients with low prognosis. this study aims to assess and comparative perinatal outcomes and cLBR per cycle of in vitro fertilization/intracytoplasmic sperm injection (iVf/icSi) between four groups of low prognosis characterized by poSeiDon criteria. A retrospective assessment was done among infertile women with a low prognosis undergoing iVf/icSi at a reproductive center in china. Data were collected between January 2011 and December 2015 with a follow-up of at least two years, and censoring was defined by three-cycle completion, discontinuation, or having a live birth. Participants were grouped into 4 groups according to the POSEIDON classification (POSEIDON1, POSEIDON2, POSEIDON3, and POSEIDON4). The main outcomes were perinatal and obstetric outcomes with cLBR per cycle after iVf/icSi procedure. And iVf/icSi-technique outcomes as a secondary outcome. Statistical analyses were performed by SpSS, and a p value of < 0.05 was considered significant. A total of 461 eligible participants underwent a total of 825 IVF/ICSI cycles. POSEIDON1 had the best perinatal outcomes in terms of live births (≥ 28w) (54.8%). POSEIDON4 had a higher risk for perinatal and obstetric complications with abortion rate (9.8%); LBW (11.7%), PTD (23.5%), PROM (11.7%), and gestational diabetes (17.6%). POSEIDON2 had a high rate for malpresentation (14.2%), and cesarean delivery(57.2%), while POSEIDON3 was much associated with the occurrences of placenta previa (9.3%) compared to other groups (p value = 0.001). After adjusting odds ratio by age and BMI, POSEIDON4 had the least odds for biochemical pregnancy (p value = 0.019); and the least odds for clinical pregnancy (p value = 0.001) of the four groups. CLBR per cycle was better in POSEIDON1 and increased with an increasing number of cycles in all groups during the three cycles. conservative cLBR after three complete cycles were 77.27%, 42.52%, 51.4% and 22.34%, while optimistic CLBR were 79.01%, 51.19%, 58.59% and 34.46% in POSEIDON1 to POSEIDON4, respectively. Younger women with low prognosis and normal ovarian reserve have a higher probability for live births and better perinatal outcomes compared with older women with poor or normal ovarian reserve. Besides, young women with low prognosis, despite ovarian reserve status, can increase their probability of conception and get relatively higher cLBR by undergoing multiple cycles of iVf/icSi. Age is therefore considered as a critical parameter in predicting the perinatal outcome and cLBR.

Integrin β3 (ITGB3), which is the target gene of the miRNA let-7 that can be antagonized by long noncoding RNA (lncRNA) H19, is well known to have a critical role in endometrium receptivity. However, the regulation of ITGB3 in cell–cell or cell–extracellular matrix adhesion and invasion for the maintenance of early pregnancy remains unknown. This study aimed to explore the role of the H19/let-7/ITGB3 axis in regulating trophoblastic spheroid adhesion and in vitro invasion ability using the HTR-8/SVneo cell line and to investigate the expression levels of lncRNA H19 and ITGB3 in human products of conception. The in vitro knockdown of H19 resulted in decreased expression of ITGB3 at the mRNA and protein levels and reduced the adhesion and invasion ability. In the embryonic chorion tissue of spontaneous abortion (SA), the expressions of H19 and ITGB3 at both the mRNA and protein levels decreased. The results of quantitative RT-PCR, Western blot analysis, dual-luciferase report gene and functional miRNA let-7 rescue experiments, adhesion assay and in vitro transwell invasion assay confirmed that H19 regulated trophoblastic spheroid adhesion with endometrial stromal cells through the H19/let-7/ITGB3 axis, thereby providing an improved understanding of the molecular mechanism of SA.

Background Poor endometrial receptivity is a major factor that leads to recurrent implantation failure. However, the traditional method cannot accurately evaluate endometrial receptivity. Various studies have indicated that microRNAs (miRNAs) are involved in multiple processes of embryo implantation, but the role of miRNAs in endometrial receptivity in patients with recurrent implantation failure (RIF) remains elusive. In the present study, we investigated the presence of pinopodes and the roles of miR-30d-5p, suppressor of cytokine signalling 1 (SOCS1) and the leukaemia inhibitory factor (LIF) pathway in women with a history of RIF during the implantation window. Methods Endometrial tissue samples were collected between January 2018 to June 2019 from two groups of women who underwent in vitro fertilisation and embryo transfer (IVF-ET) or frozen ET. The RIF group included 20 women who underwent ≥ 3 ETs, including a total of ≥ 4 good-quality embryos, without pregnancy, whereas the control group included 10 women who had given birth at least once in the past year. An endometrial biopsy was performed during the implantation window (LH + 7). The development of pinopodes in the endometrial biopsy samples from all groups was evaluated using scanning electron microscopy (SEM). Quantitative reverse transcription-polymerase chain reaction and western blotting were used to investigate the expression levels of miR-30d-5p, SOCS1, and the LIF pathway. Results The presence of developed pinopodes decreased in patients with RIF on LH + 7. The expression level of miR-30d-5p decreased in the endometria during the implantation window of patients with RIF, whereas the mRNA and protein levels of SOCS1 were significantly higher in the RIF group than in the control group. Furthermore, a negative correlation was observed between the expression of miR-30d-5p and SOCS1 (r2 = 0.8362). In addition, a significant decrease in LIF and p-STAT3 expression was observed during the implantation window in patients with RIF. Conclusions MiR-30d-5p and SOCS1 may be potential biomarkers for endometrial receptivity. Changes in pinopode development and abnormal expression of miR-30d-5p, SOCS1 and LIF pathway in the endometrium could be the reasons for implantation failure.