Overexpression of steroid receptor coactivator-3 in bone cancers: An in vivo immunohistochemical study with tissue microarray

ABSTRACT Although the essential involvement of the progesterone receptor (PR) in female reproductive tissues is firmly established, the coregulators preferentially enlisted by PR to mediate its physiological effects have yet to be fully delineated. To further dissect the roles of members of the steroid receptor coactivator (SRC)/p160 family in PR-mediated reproductive processes in vivo, state-of-the-art cre-loxP engineering strategies were employed to generate a mouse model (PR Cre/+ SRC-2 flox/flox) in which SRC-2 function was abrogated only in cell lineages that express the PR. Fertility tests revealed that while ovarian activity was normal, PR Cre/+ SRC-2 flox/flox mouse uterine function was severely compromised. Absence of SRC-2 in PR-positive uterine cells was shown to contribute to an early block in embryo implantation, a phenotype not shared by SRC-1 or -3 knockout mice. In addition, histological and molecular analyses revealed an inability of the PR Cre/+ SRC-2 flox/flox mouse uterus to undergo the necessary cellular and molecular changes that precede complete P-induced decidual progression. Moreover, removal of SRC-1 in the PR Cre/+ SRC-2 flox/flox mouse uterus resulted in the absence of a decidual response, confirming that uterine SRC-2 and -1 cooperate in P-initiated transcriptional programs which lead to full decidualization. In the case of the mammary gland, whole-mount and histological analysis disclosed the absence of significant ductal side branching and alveologenesis in the hormone-treated PR Cre/+ SRC-2 flox/flox mammary gland, reinforcing an important role for SRC-2 in cellular proliferative changes that require PR. We conclude that SRC-2 is appropriated by PR in a subset of transcriptional cascades obligate for normal uterine and mammary morphogenesis and function.

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Overexpression of ClC-3 Chloride Channel in Chondrosarcoma: An In Vivo Immunohistochemical Study with Tissue Microarray

Medical Science Monitor ◽

10.12659/msm.917382 ◽

2019 ◽

Vol 25 ◽

pp. 5044-5053

Author(s):

Zhiqin Deng ◽

Wencui Li ◽

Murad Alahdal ◽

Ningfeng Zhang ◽

Junxiong Xie ◽

...

Keyword(s):

Tissue Microarray ◽

Chloride Channel ◽

Immunohistochemical Study

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Reduction of Coactivator Expression by Antisense Oligodeoxynucleotides Inhibits ERα Transcriptional Activity and MCF-7 Proliferation

Molecular Endocrinology ◽

10.1210/mend.16.2.0770 ◽

2002 ◽

Vol 16 (2) ◽

pp. 253-270 ◽

Cited By ~ 2

Author(s):

Ilaria T. R. Cavarretta ◽

Ratna Mukopadhyay ◽

David M. Lonard ◽

Lex M. Cowsert ◽

C. Frank Bennett ◽

...

Keyword(s):

Gene Expression ◽

Transcriptional Activity ◽

Steroid Receptors ◽

Biological Effects ◽

Steroid Receptor ◽

Transient Transfection ◽

Antisense Oligodeoxynucleotides ◽

Steroid Receptor Coactivator ◽

Mcf 7

Abstract Steroid receptor RNA activator (SRA) is a novel coactivator for steroid receptors that acts as an RNA molecule, whereas steroid receptor coactivator (SRC) family members, such as steroid receptor coactivator-1 (SRC-1) and transcriptional intermediary factor 2 (TIF2) exert their biological effects as proteins. Individual overexpression of each of these coactivators, which can form multimeric complexes in vivo, results in stimulated ERα transcriptional activity in transient transfection assays. However there is no information on the consequences of reducing SRC-1, TIF2, or SRA expression, singly or in combination, on ERα transcriptional activity. We therefore developed antisense oligodeoxynucleotides (asODNs) to SRA, SRC-1, and TIF2 mRNAs, which rapidly and specifically reduced the expression of each of these coactivators. ERα-dependent gene expression was reduced in a dose-dependent fashion by up to 80% in cells transfected with these oligonucleotides. Furthermore, treatment of cells with combinations of SRA, SRC-1, and TIF2 asODNs reduced ERα transcriptional activity to an extent greater than individual asODN treatment alone, suggesting that these coactivators cooperate, in at least an additive fashion, to activate ERα-dependent target gene expression. Finally, treatment of MCF-7 cells with asODN against SRC-1 and TIF2 revealed a requirement of these coactivators, but not SRA, for hormone-dependent DNA synthesis and induction of estrogen-dependent pS2 gene expression, indicating that SRA and SRC family coactivators can fulfill specific functional roles. Taken together, we have developed a rapid method to reduce endogenous coactivator expression that enables an assessment of the in vivo role of specific coactivators on ERα biological action and avoids potential artifacts arising from overexpression of coactivators in transient transfection assays.

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Immunohistochemical localization of steroid receptor coactivators in chondrosarcoma: An in vivo tissue microarray study

Pathology - Research and Practice ◽

10.1016/j.prp.2014.04.012 ◽

2014 ◽

Vol 210 (12) ◽

pp. 1005-1010 ◽

Cited By ~ 2

Author(s):

Wei Li ◽

Jingshu Fu ◽

Chen Bian ◽

Jiqiang Zhang ◽

Zhao Xie

Keyword(s):

Tissue Microarray ◽

Steroid Receptor ◽

Immunohistochemical Localization ◽

Microarray Study ◽

Steroid Receptor Coactivators

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In Vivo Interaction of Steroid Receptor Coactivator (SRC)-1 and the Activation Function-2 Domain of the Thyroid Hormone Receptor (TR) β in TRβ E457A Knock-In and SRC-1 Knockout mice

Endocrinology ◽

10.1210/en.2009-0093 ◽

2009 ◽

Vol 150 (8) ◽

pp. 3927-3934 ◽

Cited By ~ 23

Author(s):

Manuela Alonso ◽

Charles Goodwin ◽

XiaoHui Liao ◽

Tania Ortiga-Carvalho ◽

Danielle S. Machado ◽

...

Keyword(s):

Thyroid Hormone ◽

Thyroid Hormone Receptor ◽

Steroid Receptor ◽

Activation Function ◽

Steroid Receptor Coactivator ◽

Pituitary Thyroid Axis ◽

Serum T4 ◽

Thyroid Axis

The activation function-2 (AF-2) domain of the thyroid hormone (TH) receptor (TR)-β is a TH-dependent binding site for nuclear coactivators (NCoA), which modulate TH-dependent gene transcription. In contrast, the putative AF-1 domain is a TH-independent region interacting with NCoA. We determined the specificity of the AF-2 domain and NCoA interaction by evaluating thyroid function in mice with combined disruption of the AF-2 domain in TRβ, due to a point mutation (E457A), and deletion of one of the NCoAs, steroid receptor coactivator (SRC)-1. The E457A mutation was chosen because it abolishes NCoA recruitment in vitro while preserving normal TH binding and corepressor interactions resulting in resistance to TH. At baseline, disruption of SRC-1 in the homozygous knock-in (TRβE457A/E457A) mice worsened the degree of resistance to TH, resulting in increased serum T4 and TSH. During TH deprivation, disruption of AF-2 and SRC-1 resulted in a TSH rise 50% of what was seen when AF-2 alone was removed, suggesting that SRC-1 was interacting outside of the AF-2 domain. Therefore, 1) during TH deprivation, SRC-1 is necessary for activating the hypothalamic-pituitary-thyroid axis; 2) ligand-dependent repression of TSH requires an intact AF-2; and 3) SRC-1 may interact with the another region of the TRβ or the TRα to regulate TH action in the pituitary. This report demonstrates the dual interaction of NCoA in vivo: the TH-independent up-regulation possibly through another domain and TH-dependent down-regulation through the AF-2 domain.

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Modulation by Steroid Receptor Coactivator-1 of Target-Tissue Responsiveness in Resistance to Thyroid Hormone

Endocrinology ◽

10.1210/en.2003-0239 ◽

2003 ◽

Vol 144 (9) ◽

pp. 4144-4153 ◽

Cited By ~ 30

Author(s):

Yuji Kamiya ◽

Xiao-Yong Zhang ◽

Hao Ying ◽

Yusuhito Kato ◽

Mark C. Willingham ◽

...

Keyword(s):

Thyroid Hormone ◽

Target Genes ◽

Thyroid Hormone Receptor ◽

Expression Patterns ◽

Steroid Receptor ◽

Target Tissue ◽

Dependent Manner ◽

Resistance To Thyroid Hormone ◽

Steroid Receptor Coactivator

Abstract Mutations in the thyroid hormone receptor-β gene (TRβ) cause resistance to thyroid hormone. How the action of mutant thyroid hormone nuclear receptors (TRs) is regulated in vivo is not clear. We examined the effect of a TR coactivator, steroid receptor coactivator-1 (SRC-1), on target-tissue responsiveness by using a mouse model of resistance to thyroid hormone, TRβPV knockin mice, in the SRC-1 null background. Lack of SRC-1 intensified the dysfunction of the pituitary-thyroid axis and impaired growth in TRβPV/+ mice but not in TRβPV/PV mice. In TRβPV/PV mice, however, lack of SRC-1 intensified the pathological progression of thyroid follicular cells to papillary hyperplasia, reminiscent of papillary neoplasia. In contrast, lack of SRC-1 did not affect responsiveness in the liver in regulating serum cholesterol in either TRβPV/+ or TRβPV/PV mice. Lack of SRC-1 led to changes in the abnormal expression patterns of several T3 target genes in the pituitary and liver. Thus, the present studies show that a coactivator such as SRC-1 could modulate the in vivo action of TRβ mutants in a tissue-dependent manner.

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Peptidyl-Prolyl Isomerase 1 (Pin1) Serves as a Coactivator of Steroid Receptor by Regulating the Activity of Phosphorylated Steroid Receptor Coactivator 3 (SRC-3/AIB1)

Molecular and Cellular Biology ◽

10.1128/mcb.25.21.9687-9699.2005 ◽

2005 ◽

Vol 25 (21) ◽

pp. 9687-9699 ◽

Cited By ~ 70

Author(s):

Ping Yi ◽

Ray-Chang Wu ◽

Joshua Sandquist ◽

Jiemin Wong ◽

Sophia Y. Tsai ◽

...

Keyword(s):

Conformational Changes ◽

Intracellular Signaling ◽

Steroid Receptors ◽

Steroid Receptor ◽

Dependent Manner ◽

Prolyl Isomerase ◽

Peptidyl Prolyl Isomerase ◽

Steroid Receptor Coactivator

ABSTRACT Steroid receptor coactivator 3 (SRC-3/AIB1) interacts with steroid receptors in a ligand-dependent manner to activate receptor-mediated transcription. A number of intracellular signaling pathways initiated by growth factors and hormones induce phosphorylation of SRC-3, regulating its function and contributing to its oncogenic potential. However, the range of mechanisms by which phosphorylation affects coactivator function remains largely undefined. We demonstrate here that peptidyl-prolyl isomerase 1 (Pin1), which catalyzes the isomerization of phosphorylated Ser/Thr-Pro peptide bonds to induce conformational changes of its target proteins, interacts selectively with phosphorylated SRC-3. In addition, Pin1 and SRC-3 activate nuclear-receptor-regulated transcription synergistically. Depletion of Pin1 by small interfering RNA (siRNA) reduces hormone-dependent transcription from both transfected reporters and an endogenous steroid receptor target gene. We present evidence that Pin1 modulates interactions between SRC-3 and CBP/p300. The interaction is enhanced in vitro and in vivo by Pin1 and diminished when cellular Pin1 is reduced by siRNA or in stable Pin1-depleted cell lines. Depletion of Pin1 in MCF-7 human breast cancer cells reduces the endogenous estrogen-dependent recruitment of p300 to the promoters of estrogen receptor-dependent genes. Pin1 overexpression enhanced SRC-3 cellular turnover, and depletion of Pin1 stabilized SRC-3. Our results suggest that Pin1 functions as a transcriptional coactivator of nuclear receptors by modulating SRC-3 coactivator protein-protein complex formation and ultimately by also promoting the turnover of the activated SRC-3 oncoprotein.

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Genetic Ablation of the Steroid Receptor Coactivator-Ubiquitin Ligase, E6-AP, Results in Tissue-Selective Steroid Hormone Resistance and Defects in Reproduction

Molecular and Cellular Biology ◽

10.1128/mcb.22.2.525-535.2002 ◽

2002 ◽

Vol 22 (2) ◽

pp. 525-535 ◽

Cited By ~ 54

Author(s):

Carolyn L. Smith ◽

Darryll G. DeVera ◽

Dolores J. Lamb ◽

Zafar Nawaz ◽

Yong-Hui Jiang ◽

...

Keyword(s):

Mammary Gland ◽

Ubiquitin Ligase ◽

Steroid Hormone ◽

Steroid Receptor ◽

Null Mouse ◽

Wild Type ◽

Male And Female ◽

Genetic Ablation ◽

Steroid Receptor Coactivator

ABSTRACT The E6-associated protein (E6-AP), although originally identified as a ubiquitin ligase, has recently been shown to function as a coactivator of steroid receptor-dependent gene expression in in vitro assays. In order to determine whether E6-AP acts as a coactivator in vivo, physiological parameters associated with male and female sex steroid action were assessed in the E6-AP null mouse. Gonadal size was reduced in E6-AP null male and female mice in comparison to wild-type controls in conjunction with reduced fertility in both genders. Consistent with this observation, defects in sperm production and function, as well as ovulation were observed. In comparison to wild-type controls, induction of prostate gland growth induced by testosterone and uterine growth by estradiol were significantly reduced. In contrast, estrogen and progesterone-stimulated growth of virgin mammary gland was not compromised by E6-AP ablation despite E6-AP expression in this tissue. This latter finding contrasts with the impaired estrogen and progesterone-induced mammary gland development observed previously for steroid receptor coactivator type 1 (SRC-1) and SRC-3 female knockout mice. Taken together, these results are consistent with a role for E6-AP in mediating a subset of steroid hormone actions in vivo. Nevertheless, differences observed between SRC and E6-AP knockout phenotypes indicate that these two families of steroid receptor coactivators are not functionally equivalent and supports the hypothesis that coactivators contribute to tissue-specific steroid hormone action.

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Stimulation of Steroid Receptor Coactivator-3 (SRC-3) Gene Overexpression by a Positive Regulatory Loop of E2F1 and SRC-3

Molecular Endocrinology ◽

10.1210/me.2005-0522 ◽

2006 ◽

Vol 20 (12) ◽

pp. 3105-3119 ◽

Cited By ~ 42

Author(s):

Paola Mussi ◽

Chundong Yu ◽

Bert W. O’Malley ◽

Jianming Xu

Keyword(s):

Breast Cancer ◽

Binding Sites ◽

Promoter Activity ◽

Steroid Receptor ◽

Regulatory Sequence ◽

Dependent Manner ◽

Breast Cancers ◽

Steroid Receptor Coactivator ◽

Regulatory Loop

Abstract Steroid receptor coactivator 3 (SRC-3, amplified in breast cancer 1, or ACTR) is a transcriptional coactivator for nuclear receptors and certain other transcription factors such as E2F1. SRC-3 is overexpressed in breast cancers, and its overexpression is sufficient to cause mammary carcinomas in vivo. However, the mechanisms controlling endogenous SRC-3 overexpression are unknown. In this study, we identified the first exon and analyzed the 5′ regulatory sequence of the SRC-3 gene. We found three evolutionarily conserved regions (ECRs) in the 5′ SRC-3 regulatory sequence, and ECR2 makes a major contribution to the SRC-3 promoter activity. The ECR2 region (bp −250/+350) contains several specificity protein 1 (Sp1) binding sites and two E2F1 binding sites. We show that E2F1 can significantly activate the ECR2 promoter activity in a dose-dependent manner. Furthermore, overexpression of E2F1 significantly increases the promoter activity of the endogenous SRC-3 gene and boosts SRC-3 expression in vivo. Conversely, knockdown of E2F1 reduces SRC-3 expression. We demonstrate that the mechanism of E2F1 activity on SRC-3 promoter is independent of the E2F binding sites but relies on the Sp1 element located at bp +150/+160. Sp1, E2F1, and SRC-3 are specifically recruited to this Sp1 site and the interaction between E2F1 and Sp1 is essential to modulate SRC-3 expression. Moreover, SRC-3 coactivates E2F1 activity and thereby additively stimulates a further increase in SRC-3 expression in vivo. These results suggest that in cells with hyperactive E2F1, such as the case encountered in breast cancer cells, there is a positive feedback regulatory loop consisting of E2F1 and SRC-3 to maintain high levels of SRC-3 and E2F1 activity, which may partially interpret the oncogenic role of SRC-3 overexpression.

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