| 1. |
- Haigh, Daisy B., et al.
(författare)
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The METTL3 RNA Methyltransferase Regulates Transcriptional Networks in Prostate Cancer
- 2022
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Ingår i: Cancers. - : MDPI. - 2072-6694. ; 14:20
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Tidskriftsartikel (refereegranskat)abstract
- Prostate cancer (PCa) is a leading cause of cancer-related deaths and is driven by aberrant androgen receptor (AR) signalling. For this reason, androgen deprivation therapies (ADTs) that suppress androgen-induced PCa progression either by preventing androgen biosynthesis or via AR signalling inhibition (ARSi) are common treatments. The N6-methyladenosine (m6A) RNA modification is involved in regulating mRNA expression, translation, and alternative splicing, and through these mechanisms has been implicated in cancer development and progression. RNA-m6A is dynamically regulated by the METTL3 RNA methyltransferase complex and the FTO and ALKBH5 demethylases. While there is evidence supporting a role for aberrant METTL3 in many cancer types, including localised PCa, the wider contribution of METTL3, and by inference m6A, in androgen signalling in PCa remains poorly understood. Therefore, the aim of this study was to investigate the expression of METTL3 in PCa patients and study the clinical and functional relevance of METTL3 in PCa. It was found that METTL3 is aberrantly expressed in PCa patient samples and that siRNA-mediated METTL3 knockdown or METTL3-pharmacological inhibition significantly alters the basal and androgen-regulated transcriptome in PCa, which supports targeting m6A as a novel approach to modulate androgen signalling in PCa.
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| 2. |
- Harris, Anna E., et al.
(författare)
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Exploring anti-androgen therapies in hormone dependent prostate cancer and new therapeutic routes for castration resistant prostate cancer
- 2022
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Ingår i: Frontiers in Endocrinology. - : Frontiers Media S.A.. - 1664-2392. ; 13
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Forskningsöversikt (refereegranskat)abstract
- Androgen deprivation therapies (ADTs) are important treatments which inhibit androgen-induced prostate cancer (PCa) progression by either preventing androgen biosynthesis (e.g. abiraterone) or by antagonizing androgen receptor (AR) function (e.g. bicalutamide, enzalutamide, darolutamide). A major limitation of current ADTs is they often remain effective for limited durations after which patients commonly progress to a lethal and incurable form of PCa, called castration-resistant prostate cancer (CRPC) where the AR continues to orchestrate pro-oncogenic signalling. Indeed, the increasing numbers of ADT-related treatment-emergent neuroendocrine-like prostate cancers (NePC), which lack AR and are thus insensitive to ADT, represents a major therapeutic challenge. There is therefore an urgent need to better understand the mechanisms of AR action in hormone dependent disease and the progression to CRPC, to enable the development of new approaches to prevent, reverse or delay ADT-resistance. Interestingly the AR regulates distinct transcriptional networks in hormone dependent and CRPC, and this appears to be related to the aberrant function of key AR-epigenetic coregulator enzymes including the lysine demethylase 1 (LSD1/KDM1A). In this review we summarize the current best status of anti-androgen clinical trials, the potential for novel combination therapies and we explore recent advances in the development of novel epigenetic targeted therapies that may be relevant to prevent or reverse disease progression in patients with advanced CRPC.
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| 3. |
- Hedblom, Andreas, et al.
(författare)
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CDK1 interacts with RARγ and plays an important role in treatment response of acute myeloid leukemia
- 2013
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Ingår i: Cell Cycle. - : Taylor & Francis. - 1538-4101 .- 1551-4005. ; 12:8, s. 1251-1266
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Tidskriftsartikel (refereegranskat)abstract
- Alterations in cell cycle pathways and retinoic acid signaling are implicated in leukemogenesis. However, little is known about the roles of cyclin-dependent kinases (CDKs) in treatment response of leukemia. In this study, we observed that CDK1 expression was significantly higher in bone marrow from 42 patients with acute myeloid leukemia (AML) at recurrence than that at first diagnosis (p = 0.04). AML patients had higher level of nuclear CDK1 in their leukemic blasts tended to have poorer clinical outcome compared with those with lower levels. We showed that CDK1 function is required for all-trans retinoic acid (ATRA) to achieve the optimal effect in U-937 human leukemic cells. CDK1 modulates the levels of P27(kip) and AKT phosphorylation in response to ATRA treatment. Further, we show, for the first time, that RARγ in concert with ATRA regulates protein levels of CDK1 and its subcellular localization. The regulation of the subcellular content of CDK1 and RARγ by ATRA is an important process for achieving an effective response in treatment of leukemia. RARγ and CDK1 form a reciprocal regulatory circuit in the nucleus and influence the function and protein stability of each other and the level of P27(kip) protein. In addition, expression of wee1 kinase and Cdc25A/C phosphatases also coincide with CDK1 expression and its subcellular localization in response to ATRA treatment. Our study reveals a novel mechanism by which CDK1 and RARγ coordinate with ATRA to influence cell cycle progression and cellular differentiation.
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| 4. |
- Kashyap, Vasundhra, et al.
(författare)
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Regulation of Stem Cell Pluripotency and Differentiation Involves a Mutual Regulatory Circuit of the Nanog, OCT4, and SOX2 Pluripotency Transcription Factors With Polycomb Repressive Complexes and Stem Cell microRNAs
- 2009
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Ingår i: Stem Cells and Development. - : Mary Ann Liebert. - 1547-3287 .- 1557-8534. ; 18:7, s. 1093-1108
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Forskningsöversikt (refereegranskat)abstract
- Coordinated transcription factor networks have emerged as the master regulatory mechanisms of stem cell pluripotency and differentiation. Many stem cell-specific transcription factors, including the pluripotency transcription factors, OCT4, NANOG, and SOX2 function in combinatorial complexes to regulate the expression of loci, which are involved in embryonic stem (ES) cell pluripotency and cellular differentiation. This review will address how these pathways form a reciprocal regulatory circuit whereby the equilibrium between stem cell self-renewal, proliferation, and differentiation is in perpetual balance. We will discuss how distinct epigenetic repressive pathways involving polycomb complexes, DNA methylation, and microRNAs cooperate to reduce transcriptional noise and to prevent stochastic and aberrant induction of differentiation. We will provide a brief overview of how these networks cooperate to modulate differentiation along hematopoietic and neuronal lineages. Finally, we will describe how aberrant functioning of components of the stem cell regulatory network may contribute to malignant transformation of adult stem cells and the establishment of a "cancer stem cell" phenotype and thereby underlie multiple types of human malignancies.
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| 5. |
- Kashyap, Vasundhra, et al.
(författare)
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The lysine specific demethylase-1 (LSD1/KDM1A) regulates VEGF-A expression in prostate cancer
- 2013
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Ingår i: Molecular Oncology. - : Wiley. - 1574-7891 .- 1878-0261. ; 7:3, s. 555-566
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Tidskriftsartikel (refereegranskat)abstract
- Recurrent prostate cancer remains a major clinical challenge. The lysine specific demethylase-1 (LSD1/KDM1A), together with the JmjC domain-containing JMJD2A and JMJD2C proteins, have emerged as critical regulators of histone lysine methylation. The LSD1-JMJD2 complex functions as a transcriptional co-regulator of hormone activated androgen and estrogen receptors at specific gene promoters. LSD1 also regulates DNA methylation and p53 function. LSD1 is overexpressed in numerous cancers including prostate cancer through an unknown mechanism. We investigated expression of the LSD1 and JMJD2A in malignant human prostate specimens. We correlated LSD1 and JMJD2A expression with known mediators of prostate cancer progression: VEGF-A and cyclin A1. We show that elevated expression of LSD1, but not JMJD2A, correlates with prostate cancer recurrence and with increased VEGF-A expression. We show that functional depletion of LSD1 expression using siRNA in prostate cancer cells decreases VEGF-A and blocks androgen induced VEGF-A, PSA and Tmprss2 expression. We demonstrate that pharmacological inhibition of LSD1 reduces proliferation of both androgen dependent (LnCaP) and independent cell lines (LnCaP: C42, PC3). We show a direct mechanistic link between LSD1 overexpression and increased activity of pro-angiogenic pathways. New therapies targeting LSD1 activity should be useful in the treatment of hormone dependent and independent prostate cancer. (C) 2013 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
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| 6. |
- Kopparapu, Pradeep, et al.
(författare)
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Expression of cyclin d1 and its association with disease characteristics in bladder cancer
- 2013
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Ingår i: Anticancer Research. - 0250-7005 .- 1791-7530. ; 33:12, s. 5235-4252
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Tidskriftsartikel (refereegranskat)abstract
- AIM: Invasive urothelial carcinoma of the bladder (UCB) is characterized by alterations in cell-cycle regulatory pathways. Defects in the expression of cyclin D1, a key cell-cycle regulator, have been implicated in progression of various types of cancer. In the present study, we investigated whether cyclin D1 expression is associated with clinicopathological parameters and whether it has any potential prognostic value in determining risk of UCB recurrence.PATIENTS AND METHODS: Tissue microarrays containing bladder cancer specimens (n=212) and adjacent normal bladder tissues (n=131) were immunostained using an antibody against cyclin D1. The association between cyclin D1 and clinicopathological parameters including stage, lymph node metastasis, and disease-free survival, were evaluated. Cyclin D1 mRNA expression data from human normal bladder (n=14) and cancer specimens (n=28) were extracted from the public Oncomine database.RESULTS: Cyclin D1 mRNA and protein expression were significantly higher in UCB compared to adjacent non-malignant bladder tissue (for mRNA p=0.003, for protein p=0.001). Cyclin D1 protein expression was significantly higher in non-invasive tumors than in muscle-invasive UCB (p=0.016). Among patients with muscle-invasive UCB, increased cyclin D1 expression in tumor cells significantly correlated with lymph node metastasis (p<0.001), and there was a trend of cyclin D1 together with lymph node positivity to be associated with disease recurrence (p=0.678). Loss of nuclear cyclin D1 expression in tumor cells was likewise significantly associated with the presence of lymph node metastasis (p<0.001).CONCLUSION: Altered expression of cyclin D1 is associated with lymph node metastasis and risk of UCB recurrence. Cyclin D1 expression may therefore have clinical value as a prognostic marker and potential therapeutic target.
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| 7. |
- Kopparapu, Pradeep Kumar, et al.
(författare)
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Expression of VEGF and its receptors VEGFR1/VEGFR2 is associated with invasiveness of bladder cancer
- 2013
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Ingår i: Anticancer Research. - 0250-7005 .- 1791-7530. ; 33:6, s. 2381-2390
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Tidskriftsartikel (refereegranskat)abstract
- AIM: Vascular endothelial growth factor (VEGF) signaling is frequently altered in invasive tumor cells and is associated with patient outcome. In the present study, we examined VEGF, VEGFR1, and VEGFR2 expression in non-muscle invasive bladder cancer (NMIBC) and muscle invasive bladder cancer (MIBC), and evaluated the association between VEGF and its receptors with disease characteristics and bladder cancer recurrence.MATERIALS AND METHODS: Tissue microarrays containing bladder cancer specimens (n=212) and adjacent normal bladder mucosa (n=131) were immunostained using antibodies against VEGF, VEGFR1, and VEGFR2. The association between the expression of these proteins and clinical parameters including stage, lymph node metastasis, and recurrence-free survival were statistically evaluated. VEGF mRNA expression data were extracted from the public Oncomine database.RESULTS: VEGF and VEGFR1 mRNA levels were significantly higher in bladder cancer specimens than that of normal mucosa (for VEGF, p<0.001; for VEGFR1, p=0.02). Analysis of their expression at protein levels showed that levels of VEGF and VEGFR1 were significantly higher in NMIBC than in MIBC (p<0.001), while that of VEGFR2 was significantly higher in all cancer specimens compared to benign urothelial mucosa (p=0.001). Further-more, the expression of VEGFR2 was significantly higher in MIBC, as compared to NMIBC (p<0.001). Patients with higher levels of VEGF, VEGFR1, and VEGFR2 tended to have poorer recurrence-free survival than those with lower levels, but this was not statistically significant.CONCLUSION: Our results suggest that alterations in the expression of VEGF and VEGF receptors are associated with disease stage and recurrence.
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| 8. |
- Marcinkiewicz, Katarzyna, et al.
(författare)
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The androgen receptor and stem cell pathways in prostate and bladder cancers (review).
- 2012
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Ingår i: International Journal of Oncology. - : Spandidos Publications. - 1019-6439 .- 1791-2423. ; 40:1, s. 5-12
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Tidskriftsartikel (refereegranskat)abstract
- Bladder cancer is three times more common in men than in women. However, the physiological basis of the male predominance of bladder cancer remains poorly understood. A higher than expected association of prostate and bladder cancers has also been reported which may indicate a common mechanism of carcinogenesis. Consistent with this, androgens and the androgen receptor (AR) play essential roles in prostate carcinogenesis and are believed to play a role in bladder carcinogenesis. There is also evidence implicating cancer stem cells in prostate and bladder cancers. Indeed putative prostate and bladder cancer stem cells share some common molecular features. We highlight key proteins (CD49f, CD133, PTEN, CD44) which are implicated in both prostate and bladder cancers and are enriched in putative prostate and bladder cancer stem cells. We examine published chromatin immuno-precipitation studies analyzing the genome-wide distribution of the AR to identify AR association with, and by inference potential AR-regulation of, these loci. We discuss recent evidence indicating a role for the AR in the splicing of the key urological stem cell protein CD44. We propose a model whereby aberrant AR regulation of these putative stem cell proteins contributes to malignant transformation of prostate and bladder cells. For these reasons we propose that the relationship between androgens and cancer stem cell associated proteins warrants further investigation.
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| 9. |
- Metzler, Veronika M., et al.
(författare)
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The KDM5B and KDM1A lysine demethylases cooperate in regulating androgen receptor expression and signalling in prostate cancer
- 2023
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Ingår i: Frontiers in Cell and Developmental Biology. - : Frontiers Media S.A.. - 2296-634X. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- Histone H3 lysine 4 (H3K4) methylation is key epigenetic mark associated with active transcription and is a substrate for the KDM1A/LSD1 and KDM5B/JARID1B lysine demethylases. Increased expression of KDM1A and KDM5B is implicated in many cancer types, including prostate cancer (PCa). Both KDM1A and KDM5B interact with AR and promote androgen regulated gene expression. For this reason, there is great interested in the development of new therapies targeting KDM1A and KDM5B, particularly in the context of castrate resistant PCa (CRPC), where conventional androgen deprivation therapies and androgen receptor signalling inhibitors are no longer effective. As there is no curative therapy for CRPC, new approaches are urgently required to suppress androgen signalling that prevent, delay or reverse progression to the castrate resistant state. While the contribution of KDM1A to PCa is well established, the exact contribution of KDM5B to PCa is less well understood. However, there is evidence that KDM5B is implicated in numerous pro-oncogenic mechanisms in many different types of cancer, including the hypoxic response, immune evasion and PI3/AKT signalling. Here we elucidate the individual and cooperative functions of KDM1A and KDM5B in PCa. We show that KDM5B mRNA and protein expression is elevated in localised and advanced PCa. We show that the KDM5 inhibitor, CPI-455, impairs androgen regulated transcription and alternative splicing. Consistent with the established role of KDM1A and KDM5B as AR coregulators, we found that individual pharmacologic inhibition of KDM1A and KDM5 by namoline and CPI-455 respectively, impairs androgen regulated transcription. Notably, combined inhibition of KDM1A and KDM5 downregulates AR expression in CRPC cells. Furthermore, combined KDM1A and KDM5 inhibition impairs PCa cell proliferation and invasion more than individual inhibition of KDM1A and KDM5B. Collectively our study has identified individual and cooperative mechanisms involving KDM1A and KDM5 in androgen signalling in PCa. Our findings support the further development of KDM1A and KDM5B inhibitors to treat advanced PCa. Further work is now required to confirm the therapeutic feasibility of combined inhibition of KDM1A and KDM5B as a novel therapeutic strategy for targeting AR positive CRPC.
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| 10. |
- Nilsson, Emeli M., et al.
(författare)
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MiR137 is an androgen regulated repressor of an extended network of transcriptional coregulators
- 2015
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Ingår i: Oncotarget. - : Impact Journals LLC. - 1949-2553. ; 6:34, s. 35710-35725
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Tidskriftsartikel (refereegranskat)abstract
- Androgens and the androgen receptor (AR) play crucial roles in male development and the pathogenesis and progression of prostate cancer (PCa). The AR functions as a ligand dependent transcription factor which recruits multiple enzymatically distinct epigenetic coregulators to facilitate transcriptional regulation in response to androgens. Over-expression of AR coregulators is implicated in cancer. We have shown that over-expression of KDM1A, an AR coregulator, contributes to PCa recurrence by promoting VEGFA expression. However the mechanism(s) whereby AR coregulators are increased in PCa remain poorly understood. In this study we show that the microRNA hsa-miR-137 (miR137) tumor suppressor regulates expression of an extended network of transcriptional coregulators including KDM1A/LSD1/AOF1, KDM2A/JHDM1A/FBXL11, KDM4A/JMJD2A, KDM5B JARID1B/PLU1, KDM7A/JHDM1D/PHF8, MED1/TRAP220/DRIP205 and NCoA2/SRC2/TIF2. We show that expression of miR137 is increased by androgen in LnCaP androgen PCa responsive cells and that the miR137 locus is epigenetically silenced in androgen LnCaP:C4-2 and PC3 independent PCa cells. In addition, we found that restoration of miR137 expression down-regulates expression of VEGFA, an AR target gene, which suggests a role of miR137 loss also in cancer angiogenesis. Finally we show functional inhibition of miR137 function enhanced androgen induction of PSA/KLK3 expression. Our data indicate that miR137 functions as an androgen regulated suppressor of androgen signaling by modulating expression of an extended network of transcriptional coregulators. Therefore, we propose that epigenetic silencing of miR137 is an important event in promoting androgen signaling during prostate carcinogenesis and progression.
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