| 1. |
- Hagman, Zandra, et al.
(författare)
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miR-205 negatively regulates the androgen receptor and is associated with adverse outcome of prostate cancer patients.
- 2013
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Ingår i: British Journal of Cancer. - : Springer Science and Business Media LLC. - 1532-1827 .- 0007-0920. ; 108:8, s. 1668-1676
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Tidskriftsartikel (refereegranskat)abstract
- Background:The microRNA-205 (miR-205) has been shown to be deregulated in prostate cancer (PCa). Here we continue to investigate the prognostic and therapeutic potential of this microRNA.Methods:The expression of miR-205 is measured by qRT-PCR and in situ hybridisation in a well-documented PCa cohort. An AGO2-based RIP-Chip assay is used to identify targets that are verified with western blots, luciferase reporter assay, ELISA and immunohistochemistry.Results:The expression of miR-205 is inversely correlated to the occurrence of metastases and shortened overall survival, and is lower in castration-resistant PCa patients. The miR-205 expression is mainly localised to the basal cells of benign prostate tissues. Genes regulated by miR-205 are enriched in, for example, the MAPK/ERK, Toll-like receptor and IL-6 signaling pathways. We demonstrate binding of miR-205 to the 3'UTR of androgen receptor (AR) and decrease of both AR transcript and protein levels. This finding was corroborated in the patient cohort were miR-205 expression inversely correlated to AR immunostaining in malignant prostate cells and to serum levels of prostate-specific antigen, an androgen-regulated protein.Conclusion:Taken together, these findings imply that miR-205 might have therapeutic potential, especially for the castration resistant and currently untreatable form of PCa.British Journal of Cancer advance online publication, 9 April 2013; doi:10.1038/bjc.2013.131 www.bjcancer.com.
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| 2. |
- Achari, Chandrani, et al.
(författare)
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Expression of miR-34c induces G2/M cell cycle arrest in breast cancer cells
- 2014
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Ingår i: BMC Cancer. - : Springer Science and Business Media LLC. - 1471-2407. ; 14
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Tidskriftsartikel (refereegranskat)abstract
- Background: MicroRNA-34 is a family of three miRNAs that have been reported to function as tumor suppressor miRNAs and show decreased expression in various cancers. Here, we examine functions of miR-34c in basal-like breast cancer cells. Methods: Data from The Cancer Genome Atlas (TCGA) were used for evaluation of expression in primary breast cancers. Cellular processes affected by miR-34c were investigated by thymidine incorporation, Annexin V-assays and cell cycle analysis using breast cancer cell lines. Effects on potential targets were analyzed with qPCR and Western blot. Results: TCGA data revealed that miR-34c was expressed at lower levels in basal-like breast cancer tumors and low expression was associated with poor prognosis. Ectopic expression of miR-34c in basal-like breast cancer cell lines resulted in suppressed proliferation and increased cell death. Additionally, miR-34c influenced the cell cycle mainly by inducing an arrest in the G2/M phase. We found that expression levels of the known cell cycle-regulating miR-34 targets CCND1, CDK4 and CDK6, were downregulated upon miR-34c expression in breast cancer cell lines. In addition, the levels of CDC23, an important mediator in mitotic progression, were suppressed following miR-34c expression, and siRNAs targeting CDC23 mimicked the effect of miR-34c on G2/M arrest. However, protein levels of PRKCA, a predicted miR-34c target and a known regulator of breast cancer cell proliferation were not influenced by miR-34c. Conclusions: Together, our results support the role of miR-34c as a tumor suppressor miRNA also in breast cancer.
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| 3. |
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| 4. |
- Haflidadottir, Benedikta, et al.
(författare)
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Upregulation of miR-96 Enhances Cellular Proliferation of Prostate Cancer Cells through FOXO1.
- 2013
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 8:8
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Tidskriftsartikel (refereegranskat)abstract
- Aberrant expression of miR-96 in prostate cancer has previously been reported. However, the role and mechanism of action of miR-96 in prostate cancer has not been determined. In this study, the diagnostic and prognostic properties of miR-96 expression levels were investigated by qRT-PCR in two well documented prostate cancer cohorts. The miR-96 expression was found to be significantly higher in prostate cancer patients and correlate with WHO grade, and decreased overall survival time; patients with low levels of miR-96 lived 1.5 years longer than patients with high miR-96 levels. The therapeutic potential was further investigated in vitro, showing that ectopic levels of miR-96 enhances growth and cellular proliferation in prostate cancer cells, implying that miR-96 has oncogenic properties in this setting. We demonstrate that miR-96 expression decreases the transcript and protein levels of FOXO1 by binding to one of two predicted binding sites in the FOXO1 3'UTR sequence. Blocking this binding site completely inhibited the growth enhancement conveyed by miR-96. This finding was corroborated in a large external prostate cancer patient cohort where miR-96 expression inversely correlated to FOXO1 expression. Taken together these findings indicate that miR-96 plays a key role in prostate cancer cellular proliferation and can enhance prostate cancer progression. This knowledge might be utilized for the development of novel therapeutic tools for prostate cancer.
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| 5. |
- Hagman, Zandra, et al.
(författare)
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miR-34c is down regulated in prostate cancer and exerts tumor suppressive functions.
- 2010
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Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136. ; 127:12, s. 2768-2776
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Tidskriftsartikel (refereegranskat)abstract
- MicroRNAs (miRNAs) are small non-coding RNAs that post-transcriptionally regulate gene expression. There have been several reports of miRNA deregulation in prostate cancer and the biological evidence for an involvement of miRNAs in prostate tumorigenesis is increasing. In this study, we show that miR-34c is downregulated in prostate cancer (p = 0.0005) by performing qRT-PCR on 49 TURPs from prostate cancer patients compared to 25 from patients with benign prostatic hyperplasia. The miR-34c expression was found to inversely correlate to aggressiveness of the tumour, WHO grade, PSA levels and occurrence of metastases. Furthermore, a Kaplan-Meier analysis of patient survival based on miR-34c expression levels divided into low (<50(th) percentile) and high (> 50(th) percentile) expression, significantly divides the patients into high risk and low risk patients (p = 0.0003, long-rank test). The phenotypic effects of miR-34c deregulation were studied in prostate cell lines, where ectopic expression of miR-34c decreased cell growth, due to both a decrease in cellular proliferation rate and an increase in apoptosis. In concordance to this, miR-34c was found to negatively regulate the oncogenes E2F3 and BCL-2, which stimulates proliferation and suppress apoptosis in prostate cancer cells respectively. Reversely, we could also show that blocking miR-34c in vitro increases cell growth. Further, ectopic expression of miR-34c was found to suppress migration and invasion. Our findings provide new insight into the role of miR-34c in the prostate, exhibiting tumor suppressing effects on proliferation, apoptosis and invasiveness. (c) 2010 UICC.
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| 6. |
- Hagman, Zandra, et al.
(författare)
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The tumour suppressor miR-34c targets MET in prostate cancer cells.
- 2013
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Ingår i: British Journal of Cancer. - : Springer Science and Business Media LLC. - 1532-1827 .- 0007-0920. ; 109:5, s. 1271-1278
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Tidskriftsartikel (refereegranskat)abstract
- Background:The microRNA, miR-34c, is a well-established regulator of tumour suppression. It is downregulated in most forms of cancers and inhibits malignant growth by repressing genes involved in processes such as proliferation, anti-apoptosis, stemness, and migration. We have previously reported downregulation and tumour suppressive properties for miR-34c in prostate cancer (PCa).Methods:In this study, we set out to further characterize the mechanisms by which miR-34c deregulation contributes to PCa progression. The genes regulated by miR-34c in the PCa cell line PC3 were identified by microarray analyses and were found to be enriched in cell death, cell cycle, cellular growth, and cellular movement pathways. One of the identified targets was MET, a receptor tyrosine kinase activated by hepatocyte growth factor, that is crucial for metastatic progression.Results:We confirmed the inhibitory effect of miR-34c on both MET transcript and protein levels. The binding of miR-34c to two binding sites in the 3'-UTR of MET was validated using luciferase reporter assays and target site blockers. The effect of this regulation on the miR-34c inhibition of the migratory phenotype was also confirmed. In addition, a significant inverse correlation between miR-34c expression levels and MET immunostaining was found in PCa patients.Conclusion:These findings provide a novel molecular mechanism of MET regulation in PCa and contribute to the increasing evidence that miR-34c has a key tumour suppressive role in PCa.British Journal of Cancer advance online publication, 6 August 2013; doi:10.1038/bjc.2013.449 www.bjcancer.com.
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| 7. |
- Larne, Olivia, et al.
(författare)
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miQ - a novel microRNA based diagnostic and prognostic tool for prostate cancer.
- 2013
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Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136. ; 132:12, s. 2867-2875
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Tidskriftsartikel (refereegranskat)abstract
- Today, the majority of prostate tumours are detected at early stages with uncertain prognosis. Therefore, we set out to identify early predictive markers of prostate cancer with aggressive progression characteristics. We measured the expression of microRNAs (miRNA) using qRT-PCR in FFPE prostatic tissue samples from a Swedish cohort of 49 patients with prostate cancer and 25 without cancer and found eight of 14 preselected miRNAs to discriminate between the two groups. Subsequently four discriminatory miRNAs were combined to a quota, denoted the miRNA index quote (miQ); ((miR-96-5p x miR-183-5p)/(miR-145-5p x miR221-5p)). The advantage using a quote is increased discrimination, no need for house-keepings, and most important it may be an advantage considering the heterogeneity of the disease. miQ was found to successfully predict diagnosis (p<0.0001) with high accuracy (AUC=0.931) that was verified in an independent Dutch cohort and three external cohorts, and significantly outperforming PSA. Importantly, miQ also has prognostic power to predict aggressiveness of tumours (AUC=0.895), metastatic statues (AUC=0.827), and overall survival (p=0.0013, Wilcoxon test HR=6.5, median survival 2 versus 5 years), verified in the Dutch cohort. In this preliminary study we propose that miQ has potential to be used as a clinical tool for prostate cancer diagnosis and as a prognostic marker of disease progression. © 2012 Wiley Periodicals, Inc.
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| 8. |
- Magnusson, Cecilia, et al.
(författare)
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Regulation of cysteinyl leukotriene receptor 2 expression-a potential anti-tumor mechanism.
- 2011
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 6:12
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Tidskriftsartikel (refereegranskat)abstract
- The cysteinyl leukotrienes receptors (CysLTRs) are implicated in many different pathological conditions, such as inflammation and cancer. We have previously shown that colon cancer patients with high CysLT(1)R and low CysLT(2)R expression demonstrate poor prognosis. Therefore, we wanted to investigate ways for the transcriptional regulation of CysLT(2)R, which still remains to be poorly understood.
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| 9. |
- Ostling, Päivi, et al.
(författare)
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Systematic Analysis of MicroRNAs Targeting the Androgen Receptor in Prostate Cancer Cells.
- 2011
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Ingår i: Cancer Research. - 1538-7445. ; 71, s. 1956-1967
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Tidskriftsartikel (refereegranskat)abstract
- Androgen receptor (AR) is expressed in all stages of prostate cancer progression, including in castration-resistant tumors. Eliminating AR function continues to represent a focus of therapeutic investigation, but AR regulatory mechanisms remain poorly understood. To systematically characterize mechanisms involving microRNAs (miRNAs), we conducted a gain-of function screen of 1129 miRNA molecules in a panel of human prostate cancer cell lines and quantified changes in AR protein content using protein lysate microarrays. In this way, we defined 71 unique miRNAs that influenced the level of AR in human prostate cancer cells. RNA sequencing data revealed that the 3'UTR of AR (and other genes) is much longer than currently used in miRNA target prediction programs. Our own analyses predicted that most of the miRNA regulation of AR would target an extended 6 kb 3'UTR. 3'UTR-binding assays validated 13 miRNAs that are able to regulate this long AR 3'UTR (miR-135b, miR-185, miR-297, miR-299-3p, miR-34a, miR-34c, miR-371-3p, miR-421, miR-449a, miR-449b, miR-634, miR-654-5p, and miR-9). Fifteen AR downregulating miRNAs decreased androgen-induced proliferation of prostate cancer cells. In particular, analysis of clinical prostate cancers confirmed a negative correlation of miR-34a and miR-34c expression with AR levels. Our findings establish that miRNAs interacting with the long 3'UTR of the AR gene are important regulators of AR protein levels, with implications for developing new therapeutic strategies to inhibit AR function and androgen-dependent cell growth. Cancer Res; 71(5); 1-12. ©2011 AACR.
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