MicroRNA-20b promotes cell growth of breast cancer cells partly via targeting phosphatase and tensin homologue (PTEN)

BACKGROUND: MicroRNAs (miRNAs) are endogenous, small non-coding RNAs that play important roles in multiple biological processes. MiR-20b has been reported to participate in breast cancer tumorigenic progression, however, the functional roles are still unclear and under debating. The aim of this study is to explicit the molecular mechanism of miR-20b underlying breast cancer tumorigenesis. RESULTS: In the present study, we showed that miR-20b was overexpressed in human breast cancer tissues and cell lines compared with paired adjacent normal tissues and normal cell lines, respectively. We identified PTEN, a well-known tumor suppressor, as the functional downstream target of miR-20b. Luciferase assays confirmed that miR-20b could directly bind to the 3′ untranslated region(UTR) of PTEN and suppress translation. Alteration of miR-20b expression changed PTEN protein level but not mRNA expression in ZR-75-30 and MCF-7 breast cancer cells, suggesting miR-20b regulates PTEN gene expression at the posttranscriptional level. Furthermore, upregulation of miR-20b significantly promoted the proliferation, colony formation and DNA synthesis of ZR-75-30 and MCF-7 breast cancer cells. Conversely, knockdown of miR-20b expression inhibited the growth of breast cancer cells in vitro and in vivo. CONCLUSION: Dysregulation of miR-20b plays critical roles in the breast cancer tumorigenesis, at least in part via targeting the tumor suppressor PTEN. This microRNA may serve as a potential diagnostic marker and therapeutic target for breast cancer. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/2045-3701-4-62) contains supplementary material, which is available to authorized users

Aberrant expression of decoy receptor 3 in human breast cancer: relevance to lymphangiogenesis

AbstractBackgroundDecoy receptor 3 (DcR3), a decoy receptor against Fas ligand belonging to the tumor necrosis factor receptor superfamily, is overexpressed in some forms of cancer. It was recently reported that DcR3 could protect endothelial cells from apoptosis, implying a potential role in the development of vessels, whereas its role in the lymphangiogenesis remains unclear. In the present study, we studied the DcR3 expression and its relationship with the lymphatic microvessel density (LMVD) to investigate if it played a role in the lymph metastasis of human breast cancer.Materials and methodsReal-time polymerase chain reaction and immunohistochemistry were performed to measure the messenger RNA and protein expression of DcR3 in the breast cancer tissues, noncancerous counterparts, and axillary lymph node from 63 patients. LMVD in these specimens was assessed by counting the D2-40 labeled–microvessels. Furthermore, the correlations between DcR3 expression and LMVD and other clinicopathologic parameters were analyzed.ResultsDcR3 was overexpressed in the breast cancer tissue of 58 patients (92.1%) and was also expressed in vascular endothelial cells and tumor cells in the lymph nodes. LMVD in cancer tissue and lymph nodes were both positively correlated to the aberrant expression of DcR3.ConclusionsThe relevance between DcR3 overexpression and LMVD revealed the existence of possible links between DcR3 and lymphangiogenesis. Based on these findings, it is important to further explore the regulation of lymphangiogenesis operated by the reverse tumor necrosis factor signaling of DcR3

Chronic and Cumulative Adverse Life Events in Women with Primary Ovarian Insufficiency:An Exploratory Qualitative Study

BACKGROUND AND PURPOSE: Primary ovarian insufficiency (POI) has serious physical and psychological consequences due to estradiol deprivation, leading to increased morbidity and mortality. However, the causes of most POI cases remain unknown. Psychological stress, usually caused by stressful life events, is known to be negatively associated with ovarian function. It is important to explore high-frequency adverse life events among women with POI for future interventions. METHODS: Forty-three women (mean age=33·8 years) were recruited who were newly- diagnosed with idiopathic POI (FSH levels >40 IU/L) to participate in semi-structured interviews through convenience sampling. The main questions covered by the topic guide were designed to explore adverse life events prior to POI diagnosis. Interviews were audio recorded, transcribed and analyzed thematically. Data were analyzed from June 2019 to August 2020. RESULTS: Among the women with POI, mean age at diagnosis of POI was 33·8 years (range from 19 to 39 years), and the average time between the onset of irregular menstruation and POI diagnosis was 2.3 years. These women with POI had a relatively normal menstrual cycle before the diagnosis. A number of stressful life events prior to POI diagnosis were discussed by them as important factors influencing their health. Four core themes emerged: 1) persistent exposure to workplace stress, 2) persistent exposure to family-related adverse life events, 3) sleep problem/disturbance existed in women with POI before diagnosis, and 4) participants’ general cognition and concerns about POI. CONCLUSIONS: Persistent exposures to adverse life events related to work stress, family stress and sleep problem existed in women with POI. Our findings are consistent with the hypothesis that adverse life events play a role in the development of POI. Future research should investigate how social environmental factors influence POI disease risks, and whether provision of tailored interventions (i.e. preventing or mitigating impact of adverse life events) aimed at high-risk populations may help prevent new POI cases and improve conditions of women with POI. We gained an in-depth understanding of the experiences of these women via 1:1 qualitative method, and find adverse life events are frequent in women with POI prior to the diagnosis

SMSC administration decreased ovary inflammation and improved folliculogenesis transcription.

<p>A) Analysis of pro- and anti-inflammatory cytokine gene expression as performed by qPCR. Administration of SMSCs 7 days after chemotherapy resulted in significantly less gene expression for TNF-α, TGF-β, IL-8, IL-6, IL-1β, and IFN-γ than in untreated control mice (*<i>P</i><0.05, **<i>P</i><0.01, ***<i>P</i><0.01). B) Expression of oocyte-specific genes in treated and untreated recipient mouse ovaries. Quantitative real-time RT-PCR showed that the relative expression of Nobox, Nanos3, and Lhx 8 was significantly higher in the SMSC group compared than among untreated controls (**<i>P</i><0.01). 18s rRNA served as an internal housekeeping gene. Data represent mean±SE of 3 independent experiments.</p

Numerical investigation on the impact of membrane thickness on transport phenomena in PEM fuel cells

A two-dimensional mathematical model is used to investigate the performance and transport characteristics of PEM fuel cells with different membrane thicknesses. The overall cell performance of three cases are presented and compared. In addition, the local temperature, liquid water saturation, water content and current density distributions are analyzed and compared. Results show that performance increases with decreasing membrane thickness and the local transport characteristics is also significantly affected. The ohmic loss is mainly caused by the proton transport process inside fuel cell. And a thinner membrane can enhance water back diffusion process in the membrane which is beneficial to the water management at the anode side

Skin-Derived Mesenchymal Stem Cells Help Restore Function to Ovaries in a Premature Ovarian Failure Mouse Model

<div><p>Skin-derived mesenchymal stem cells (SMSCs) can differentiate into the three embryonic germ layers. For this reason, they are considered a powerful tool for therapeutic cloning and offer new possibilities for tissue therapy. Recent studies showed that skin-derived stem cells can differentiate into cells expressing germ-cell specific markers <i>in vitro</i> and form oocytes <i>in vivo</i>. The idea that SMSCs may be suitable for the treatment of intractable diseases or traumatic tissue damage has attracted attention. To determine the ability of SMSCs to reactivate injured ovaries, a mouse model with ovaries damaged by busulfan and cyclophosphamide was developed and is described here. Female skin-derived mesenchymal stem cells (F-SMSCs) and male skin-derived mesenchymal stem cells (M-SMSCs) from red fluorescence protein (RFP) transgenic adult mice were used to investigate the restorative effects of SMSCs on ovarian function. Significant increases in total body weight and the weight of reproductive organs were observed in the treated animals. Both F-SMSCs and M-SMSCs were shown to be capable of partially restoring fertility in chemotherapy-treated females. Immunostaining with RFP and anti-Müllerian hormone (AMH) antibodies demonstrated that the grafted SMSCs survived, migrated to the recipient ovaries. After SMSCs were administered to the treated mice, real-time PCR showed that the expression levels of pro-inflammatory cytokines TNF-α, TGF-β, IL-8, IL-6, IL-1β, and IFNγ were significantly lower in the ovaries than in the untreated controls. Consistent with this observation, expression of oogenesis marker genes Nobox, Nanos3, and Lhx8 increased in ovaries of SMSCs-treated mice. These findings suggest that SMSCs may play a role within the ovarian follicle microenvironment in restoring the function of damaged ovaries and could be useful in reproductive health.</p></div