Uterine leiomyomas are extremely common estrogen and progesterone-dependent tumors of the myometrium and cause irregular uterine bleeding, severe anemia, and recurrent pregnancy loss in 15-30% of reproductive-age women. Each leiomyoma is thought to arise from a single mutated myometrial smooth muscle stem cell. Leiomyoma side-population (LMSP) cells comprising 1% of all tumor cells and displaying tumor-initiating stem cell characteristics are essential for estrogen-and progesterone-dependent in vivo growth of tumors, although they have remarkably lower estrogen/progesterone receptor levels than mature myometrial or leiomyoma cells. However, how estrogen/progesterone regulates the growth of LMSP cells via mature neighboring cells is unknown. Here, we demonstrate a critical paracrine role of the wingless-type (WNT)/β-catenin pathway in estrogen/progesterone-dependent tumorigenesis, involving LMSP and differentiated myometrial or leiomyoma cells. Estrogen/progesterone treatment of mature myometrial cells induced expression of WNT11 and WNT16, which remained constitutively elevated in leiomyoma tissues. In LMSP cells cocultured with mature myometrial cells, estrogen-progesterone selectively induced nuclear translocation of β-catenin and induced transcriptional activity of its heterodimeric partner T-cell factor and their target gene AXIN2, leading to the proliferation of LMSP cells. This effect could be blocked by a WNT antagonist. Ectopic expression of inhibitor of β-catenin and T-cell factor 4 in LMSP cells, but not in mature leiomyoma cells, blocked the estrogen/ progesterone-dependent growth of human tumors in vivo. We uncovered a paracrine role of the WNT/β-catenin pathway that enables mature myometrial or leiomyoma cells to send mitogenic signals to neighboring tissue stem cells in response to estrogen and progesterone, leading to the growth of uterine leiomyomas.WNT/β-catenin signaling | paracrine signaling | tumor biology

IL-8 produced by prostate cancer cells may be responsible for the androgen-independent growth of advanced prostate cancers. Accumulating evidence from microarray analyses and animal genetic models highlights the central involvement of the transcription factor early growth response-1 (EGR-1) in prostate carcinoma progression. It is unknown, however, whether knockdown of EGR-1 inhibits IL-8 production and IL-8-mediated tumor metastasis. Here we show that EGR-1 knockdown by a specific shRNA-Egr1 inhibited gene transcription and production of IL-8 by the human prostate cancer cell line DU145. Conversely, enforced expression of EGR-1 in EGR-1-lacking PC3 prostate cancer cells markedly enhanced IL-8 transcription and secretion. By using wild type and a series of mutant IL-8 promoter luciferase constructs, we found that the NF-B binding site is important for EGR-1 regulation of IL-8. Furthermore, silencing EGR-1 suppressed a synergistically functional interaction between EGR-1 and NF-B. Consequently, knockdown of EGR-1 inhibited IL-8-mediated tumor colony formation and invasion. Thus, targeted knockdown of EGR-1 could be an effective therapeutic approach against prostate cancer.Prostate cancer is currently the most prevalent noncutaneous cancer in men in the Western world and is the second leading cause of male death from cancer. There is considerable evidence from experimental models and studies conducted on patient samples to support a role for the pro-inflammatory chemokine interleukin 8 (IL-8) 2 in the promotion of prostate cancer progression (1, 2). Several studies have now confirmed elevated expression of IL-8 and its associated receptors in prostate cancer (3-6), although these independent studies suggest markedly different distribution patterns for IL-8 and its receptors. By using immunohistochemistry staining, IL-8 expression was detected in glandular epithelial cells of prostate cancer tissue, with little or no IL-8 staining hypertrophy or normal prostate epithelium (7,8). In contrast, Huang et al., reported that IL-8 was expressed solely by neuroendocrine rather than epithelial cells. Their analysis of benign and malignant prostate tissue cores confirmed an increased IL-8 expression that correlated with progressive disease (9). These studies suggested that there is a consistent trend of increased and concurrent expression of IL-8 and its two receptors in prostate cancer tissue; thus, indicating that prostate cancer cells are subject to a continuous autocrine/paracrine stimulus. In addition, several studies have reported the detection of increased IL-8 levels in the serum of patients with either localized or metastatic prostate cancer relative to control patients or patients with benign prostatic hypertrophy (10, 11). It is evident that future research providing a more comprehensive understanding of the transcriptional, translational, and post-translational signaling basis for IL-8-promoted cell motility and cell invasion will be required to identify viable and effective therapeutic strategies to attenuate th...

BackgroundThe yeast Pichia pastoris (P. pastoris) has become a popular ‘cell factory’ for producing heterologous proteins, but production widely varies among proteins. Cultivation temperature is frequently reported to significantly affect protein production; however, the underlying mechanisms of this effect remain unclear.ResultsA P. pastoris strain expressing recombinant human interleukin-10 (rhIL-10) under the control of the AOX1 promoter was used as the model in this study. This system shows high-yield rhIL-10 production with prolonged methanol-induction times when cultured at 20°C but low-yield rhIL-10 production and higher cell death rates when cultured at 30°C. Further investigation showed that G3-pro-rhIL10, an immature form of rhIL-10 that contains the glycosylation-modified signal peptide, remained in the ER for a prolonged period at 30°C. The retention resulted in higher ER stress levels that were accompanied by increased ROS production, Ca2+ leakage, ER-containing autophagosomes, shortened cortical ER length and compromised induction of the unfolded protein response (UPR). In contrast, G3-pro-rhIL10 was quickly processed and eliminated from the ER at 20°C, resulting in a lower level of ER stress and improved rhIL-10 production.ConclusionsHigh-temperature cultivation of an rhIL-10 expression strain leads to prolonged retention of immature G3-pro-rhIL10 in ER, causing higher ER stress levels and thus greater yeast cell death rates and lower production of rhIL-10.Electronic supplementary materialThe online version of this article (doi:10.1186/s12934-014-0163-7) contains supplementary material, which is available to authorized users.

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Aim We performed a meta-analysis to evaluate the efficacy and safety of dutasteride and finasteride in treating men with androgenetic alopecia (AGA) during a 24-week treatment cycle. Methods Randomized controlled trials of dutasteride and finasteride for treating AGA were searched using MEDLINE, EMBASE, and the Cochrane Controlled Trials Register. The data were calculated using Rev Man v5.3.0. The reference lists of retrieved studies were also investigated. Results Three articles including 576 participants which compared dutasteride with finasteride were selected for our analysis. The mean change in total hair count (mean difference [MD], 28.57; 95% CI, 18.75–38.39; P <0.00001), investigator’s assessment of global photographs for the vertex (MD, 0.68; 95% CI, 0.13–1.23; P =0.02) and frontal (MD, 0.63; 95% CI, 0.13–1.13; P =0.01) views, panel global photographic assessment for the vertex (MD, 0.17; 95% CI, 0.09–0.24; P <0.00001) and frontal (MD, 0.25; 95% CI, 0.18–0.31; P <0.00001) views, and subjects’ assessment (MD, 0.56; 95% CI, 0.18–0.94; P =0.003) suggested that dutasteride provided a better efficacy in treating men with AGA compared with finasteride. With regard to the assessment of safety, altered libido ( P =0.54), erectile dysfunction ( P =0.07), and ejaculation disorders ( P =0.58), dutasteride did not show a significant difference compared with finasteride. Conclusion Dutasteride seems to provide a better efficacy compared with finasteride in treating AGA. The two drugs appear to show similar rates of adverse reactions, especially in sexual dysfunction.

Epigenetic silencing of the tumor suppressor gene, RARβ2, through histone deacetylation has been established as an important process of cervical carcinogenesis. This pivotal role has led to the suggestion that a combination of retinoids selective for RARβ2 with histone deacetylase (HDAC) inhibitors may have therapeutic potential. Valproic acid (VPA), a HDAC inhibitor, has a critical role in the regulation of gene expression through histone acetylation and causes transformed cells to undergo growth arrest, differentiation, and apoptosis. Therefore, we hypothesized that the combination of VPA and ATRA could restore RARβ2 expression, thus resulting in enhanced anti-neoplastic activity in cervical cancer. Here, we show that VPA combined with ATRA led to hyperacetylation of histone H3 and a significant alteration of gene expression in cervical cancer cells, including RARβ2 gene expression, which was upregulated 50- to 90-fold. The combination therapy effectively inhibited the growth of cervical cancer cells more than the single agent treatment both in vitro and in vivo. The additive effects were associated with a significant upregulation of p21(CIP1) and p53 as well as a pronounced decrease in p-Stat3. Furthermore, the combined treatment led to cell cycle arrest predominantly at the G1 phase, and it preferentially induced cell differentiation rather than apoptosis in cervical cancer cells. The differentiation program was determined by the presence of E-cadherinmediated adhesion and activation of the PI3K/Akt pathway. Taken together, these results provide new insight into the mechanisms of enhanced antitumor activity of the HDAC inhibitor and ATRA regimen, thus offering a new therapeutic strategy for cervical cancer patients.

Tim‐3 is a negative immunoregulator in anti‐tumor response, but its mechanism in chronic lymphocytic leukemia (CLL) is not yet clear. The aim of this study was to understand the role of Galectin‐9/Tim‐3 signaling pathway in the regulation of CD4+ T cell subsets in CLL patients. Flow cytometry results showed that the number of Treg cells obviously increased, and there was a significant Treg/Th17 imbalance in CLL patients. In addition, Tim‐3 overexpressed on the surface of Th1 and Treg cells in CLL patients. The levels of Galectin‐9 and IL‐10 were significantly elevated in patients of CLL, especially in stages of Binet B, and C. However, IFN‐γ decreased. Moreover, Galectin‐9 in CLL patients was positively correlated with the number of Tim‐3+ Treg cells and the level of IL‐10. Interestingly, when the Tim‐3/Galectin‐9 pathway was blocked in vitro, the level of IL‐10 in the culture supernatant of CD4+ T was significantly reduced, while the levels of IFN‐γ and TNF‐α were increased. After co‐culture with activated Th1 cells, the apoptosis of CLL cells was significantly increased, and this effect was reversed after treatment with Tim‐3+ Tregs. In summary, Galectin‐9/Tim‐3 are elevated in CLL and associated with disease progression. By the negative regulation of CD4+ T cells, activated Galectin‐9/Tim‐3 suppresses Th1 effector function and also promotes Treg to be involved in immune escape of CLL. This pathway might become the potential target of immunotherapy in CLL patients.

BackgroundE2F1 is the gatekeeper of the cell cycle controlling an analogous balance between proliferation and cell death. E2F1 expression is elevated in advanced prostate cancer. However, it is still unclear that the roles and mechanisms of E2F1 on prostate cancers.MethodsTargeted knockdown by interferon RNA was applied on two prostate cancer and Hela cell lines to examine the inverse correlation expression of E2F1 and ICAM-1. ICAM-1 promoter reporter and ChIP assays were used for analysis of the molecular basis of transcriptional regulation of E2F1 on ICAM-1. Co-IP assays were employed for testing the protein interaction between E2F1 and NF-κB. Tumor xenograft mice model with E2F1 and ICAM-1-knockdown prostate cancer cells were used to investigate the effects of E2F1 and ICAM-1 on antitumor immunity.ResultsE2F1 knockdown by a specific short hairpin RNA increased gene transcription and protein expression of ICAM-1. By using wild type and a series of mutant ICAM-1 promoter luciferase constructs, the NF-κB binding sites were found to be important for E2F1 regulation of ICAM-1 promoter. Targeted knockdown of E2F1 did not affect expression and phosphorylation of NF-κB and IκBα, but facilitated NF-κB binding to the ICAM-1 promoter, subsequently induced ICAM-1 transcription and production in prostate carcinoma cells. Furthermore, knockdown of E2F1 inhibited tumor growth of prostate cancer in vivo through increasing the susceptibility of tumor cells to ICAM-1-mediated anti-tumor immunity including enhancement of monocyte adhesion, leucocytes infiltration, as well as cytotoxicity against tumor cells.ConclusionsE2F1 knockdown inhibited prostate tumor growth in vitro and in vivo through sensitizing tumor cells to ICAM-1 mediated anti-immunity by NF-κB modulation, highlighting the potential of E2F1 as a therapeutic target.