The incidence of premature ovarian failure (POF), also known as ovarian insufficiency, has been increasing in recent years. Although some treatments are currently available, improved treatment strategies are urgently required. Many researchers have reported that human endometrial stem cells (HuMenSCs), which exhibit stem/progenitor cell properties in vitro repaired damaged cells in vivo. Thus, we aimed to determine whether HuMenSCs can serve as cell therapy tools and be used for the treatment of POF. After treating with cyclophosphamide, on the first estrus period (we predicted mouse estrus cycle was generally 5 days), HuMenSCs were injected into a cyclophosphamide-induced mouse model of POF. The results revealed that the HuMenSCs could survive within POF mouse ovaries for at least 14 days in vivo; further, ovaries of the HuMenSCs-transplanted group expressed higher levels of ovarian markers [AMH, inhibin α/β, and follicle-stimulating hormone receptor (FSHR)], and the proliferative marker Ki67. In addition, the ovarian weight, plasma E2 level, and the number of normal follicles increased over time in the HuMenSC group compared with the control group. Further, microarray analysis of cDNA expression patterns revealed that, after HuMenSC transplantation, the gene mRNA expression patterns in the ovarian cells following stimulation of the host ovarian niche became increasingly similar to those observed in human ovarian tissue compared with the pretransplantation mRNA expression pattern in HuMenSCs. Hence, we can safely conclude that the mesenchymal stem cell properties and in vivo survival of HuMenSCs make them ideal seed cells for stem cell transplantation in the treatment of POF.

a b s t r a c tPreviou s cDNA microarrays indicated that CLDN1 (claudin-1) is an important gene for ovarian cancer-init iating cell (OCIC) invasion and adhesion. Here, we show that the downregulation of miR-155 in OCICs correlates with CLDN1 overexpression and the suppression of OCIC invasion. Luciferase assay s indicate that miR-155 targets CLDN1 mRNA on the 3 0 UTR. CLDN1 mRNA and claudin-1 protein expressi on were significantly decreased in miR-155-OCICs. Proliferation assays and Transwell migration assays show that miR-155 significantly suppresses the proliferative and invasive capacity of OCICs. Furthermore, miR-155 suppresses the growth of OCIC xenograft tumors. Thus, overexpression of miR-155 may prevent tumorigenesis in human ovarian cancer through downregu lation of CLDN1.

No abstract

MLK3 is upregulated in metastatic melanoma, and regulates cell proliferation and invasion in melanoma cells. MLK3 is a direct target of miR-125b.

The incidence of premature ovarian failure (POF), a condition causing amenorrhea and hypergonadotropic hypoestrogenism in women before the age of 40, has been increasing in recent years. As an irreversible pathological change, improved treatment strategies for this disease are urgently needed. In this study, a type of microRNA (miR-17-3p) was used to guide the differentiation of human-induced pluripotent stem (iPS) cells into hormone-sensitive ovarian epithelial (OSE)-like cells in vitro. To prevent their morphological transformation into fibroblast-like cells, MiR-17-3p, a microRNA that suppresses vimentin expression, was transfected into human iPS cells. Subsequently, these cells were successfully induced into OSE-like cells in vitro after treatment with estrogen and cell growth factors. Compared with controls, iPS cells transfected with miR-17-3p expressed higher levels of epithelial markers (cytokeratin 7, AE1, AE3, and E-cadherin) and estrogen receptors (ERa and ERb) while levels of mesenchymal markers (fibronectin, vimentin, and N-cadherin) lowered after the induction. The human iPS cellderived OSE-like cells were then injected into cyclophosphamide-induced POF model mice to determine their potential benefit as grafts to repair ovarian tissues. The OSE-like cells survived within POF mouse ovaries for at least 14 days in vivo. Compared with the negative controls, expressions of cytokeratin 7 and ERb proteins were elevated while fibronectin and vimentin levels in ovarian tissues were downregulated in the OSE-like cell transplantation group. Moreover, the ovarian weight and plasma E 2 level increased over time in the transplantation with OSE-like cells, compared with control groups. Hence, we can draw the conclusion that iPS cells can be induced to differentiate into OSE-like cells in vitro.

No abstract

Ophiobolin O is a member of ophiobolin family, which has been proved to be a potent anti-tumor drug candidate for human breast cancer. However, the anti-tumor effect and the mechanism of ophiobolin O remain unclear. In this study, we further verified ophiobolin O-induced G1 phase arrest in human breast cancer MCF-7 cells, and found that ophiobolin O reduced the phosphorylation level of AKT and GSK3β, and induced down-regulation of cyclin D1. The inverse docking (INVDOCK) analysis indicated that ophiobolin O could bind to GSK3β, and GSK3β knockdown abolished cyclin D1 degradation and G1 phase arrest. Pre-treatment with phosphatase inhibitor sodium or thovanadate halted dephosphorylation of AKT and GSK3β, and blocked ophiobolin O-induced G1 phase arrest. These data suggest that ophiobolin O may induce G1 arrest in MCF-7 cells through interaction with AKT/GSK3β/cyclin D1 signaling. In vivo, ophiobolin O suppressed tumor growth and showed little toxicity in mouse xenograft models. Overall, these findings provide theoretical basis for the therapeutic use of ophiobolin O.

BackgroundTriptolide is a structurally unique diterpene triepoxide with potent antitumor activity. However,the effect and mechanism of triptolide on hepatocellular carcinoma (HCC) is not well studied.MethodsCells were treated with triptolide, and the anti-HCC activity of triptolide was evaluated using flow cytometry, western blot, and xenograft studies. MicroRNA microarray and quantitative reverse-transcription polymerase chain reaction was used to identify differential microRNAs induced by triptolide. Chromatin immunoprecipitation assay was employed to study the interaction between c-Myc and genomic regions of miR106b-25. MicroRNAs overexpression and knockdown experiments were performed to determine the role of these microRNAs in triptolide-induced apoptosis.ResultsTriptolide inhibited cell proliferation and induced marked apoptosis in multiple HCC cell lines with different p53 status. Several signaling molecules involved in different pathways were altered after the treatment of triptolide. Xenograft tumor volume was significantly reduced in triptolide-treated group compared with vehicle control group. Two miRNA clusters, miR-17-92 and miR-106b-25, were significantly suppressed by triptolide, which resulted in the upregulation of their common target genes, including BIM, PTEN, and p21. In HCC samples, high levels of these miRNA clusters correlated with shorter recurrence free survival. Triptolide inhibited the expression of theses miRNAs in a c-Myc-dependent manner, which enhanced triptolide-induced cell death. We further showed that triptolide down-regulated the expression of c-Myc through targeting ERCC3, a newly identified triptolide-binding protein.ConclusionsThe triptolide-induced modulation of c-Myc/miRNA clusters/target genes axis enhances its potent antitumor activity, which indicates that triptolide serves as an attractive chemotherapeutic agent against HCC.Electronic supplementary materialThe online version of this article (10.1186/s13046-018-0698-2) contains supplementary material, which is available to authorized users.