scholarly journals SHH-N non-canonically sustains androgen receptor activity in androgen-independent prostate cancer cells

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Diana Trnski ◽  
Maja Sabol ◽  
Sanja Tomić ◽  
Ivan Štefanac ◽  
Milanka Mrčela ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Androgen Receptor ◽  
Cancer Cells ◽  
Therapy Resistance ◽  
Androgen Deprivation ◽  
Prostate Cancer Cells ◽  
Androgen Independence ◽  
Androgen Receptor Activity ◽  
Signaling Activation ◽  
Androgen Independent

AbstractProstate cancer is the second most frequent cancer diagnosed in men worldwide. Localized disease can be successfully treated, but advanced cases are more problematic. After initial effectiveness of androgen deprivation therapy, resistance quickly occurs. Therefore, we aimed to investigate the role of Hedgehog-GLI (HH-GLI) signaling in sustaining androgen-independent growth of prostate cancer cells. We found various modes of HH-GLI signaling activation in prostate cancer cells depending on androgen availability. When androgen was not deprived, we found evidence of non-canonical SMO signaling through the SRC kinase. After short-term androgen deprivation canonical HH-GLI signaling was activated, but we found little evidence of canonical HH-GLI signaling activity in androgen-independent prostate cancer cells. We show that in androgen-independent cells the pathway ligand, SHH-N, non-canonically binds to the androgen receptor through its cholesterol modification. Inhibition of this interaction leads to androgen receptor signaling downregulation. This implies that SHH-N activates the androgen receptor and sustains androgen-independence. Targeting this interaction might prove to be a valuable strategy for advanced prostate cancer treatment. Also, other non-canonical aspects of this signaling pathway should be investigated in more detail and considered when developing potential therapies.

T-LAK cell-originated protein kinase (TOPK) enhances androgen receptor splice variant (ARv7) and drives androgen-independent growth in prostate cancer

2020 ◽  
Author(s):  
Lama Alhawas ◽  
Karishma S Amin ◽  
Bharath Salla ◽  
Partha P Banerjee
Keyword(s):  
Prostate Cancer ◽  
Androgen Receptor ◽  
Protein Kinase ◽  
Cancer Cells ◽  
Prostate Cancer Cells ◽  
Androgen Independence ◽  
Androgen Synthesis ◽  
Lak Cell ◽  
Androgen Independent ◽  
Constitutively Active

Abstract Despite impressive advances in the treatment of prostate cancer with various efficacious inhibitors along the androgen/androgen receptor axis, eventual development of incurable metastatic Castration-Resistant Prostate Cancer (mCRPC) is inevitable and remains a major clinical challenge. Constitutively active androgen receptor (AR) spliced variants have emerged as primary means of resistance to anti-androgens and androgen synthesis inhibitors. The alternatively spliced AR variant, ARv7, has attracted significant interest due to its constitutively active status in CRPC that drives androgen-independence. Factors that are involved in regulating ARv7 levels in CRPC are not clearly known. We recently demonstrated that a protein kinase, T-LAK cell-originated protein kinase (TOPK) level correlates with the aggressiveness of prostate cancer and its invasive behavior. In this study we investigated whether TOPK plays a role in driving androgen-independence in prostate cancer cells. Our data demonstrate that TOPK overexpression in androgen-dependent LNCaP and VCaP induces ARv7 and drives androgen-independent growth. On the other hand, pharmacological inhibition of TOPK in androgen-independent LNCaP95 and 22Rv1 represses AR transactivation, and AR stability. In summary, this study illustrates a direct role of TOPK in regulating ARv7 and driving androgen-independence in prostate cancer cells.

scholarly journals MED19 alters AR occupancy and gene expression in prostate cancer cells, driving MAOA expression and growth under low androgen

PLoS Genetics ◽  
2021 ◽  
Vol 17 (1) ◽  
pp. e1008540
Author(s):  
Hannah Weber ◽  
Rachel Ruoff ◽  
Michael J. Garabedian
Keyword(s):  
Gene Expression ◽  
Prostate Cancer ◽  
Cancer Cells ◽  
Androgen Deprivation ◽  
Monoamine Oxidase A ◽  
Lncap Cells ◽  
Prostate Cancer Cells ◽  
Cancer Cell Growth ◽  
Androgen Independence ◽  
Androgen Independent

Androgen deprivation therapy (ADT) is a mainstay of prostate cancer treatment, given the dependence of prostate cells on androgen and the androgen receptor (AR). However, tumors become ADT-resistant, and there is a need to understand the mechanism. One possible mechanism is the upregulation of AR co-regulators, although only a handful have been definitively linked to disease. We previously identified the Mediator subunit MED19 as an AR co-regulator, and reported that MED19 depletion inhibits AR transcriptional activity and growth of androgen-insensitive LNCaP-abl cells. Therefore, we proposed that MED19 upregulation would promote AR activity and drive androgen-independent growth. Here, we show that stable overexpression of MED19 in androgen-dependent LNCaP cells promotes growth under conditions of androgen deprivation. To delineate the mechanism, we determined the MED19 and AR transcriptomes and cistromes in control and MED19-overexpressing LNCaP cells. We also examined genome-wide H3K27 acetylation. MED19 overexpression selectively alters AR occupancy, H3K27 acetylation, and gene expression. Under conditions of androgen deprivation, genes regulated by MED19 correspond to genes regulated by ELK1, a transcription factor that binds the AR N-terminus to induce select AR target gene expression and proliferation, and genomic sites occupied by MED19 and AR are enriched for motifs associated with ELK1. Strikingly, MED19 upregulates expression of monoamine oxidase A (MAOA), a factor that promotes prostate cancer growth. MAOA depletion reduces androgen-independent growth. MED19 and AR occupy the MAOA promoter, with MED19 overexpression enhancing AR occupancy and H3K27 acetylation. Furthermore, MED19 overexpression increases ELK1 occupancy at the MAOA promoter, and ELK1 depletion reduces MAOA expression and androgen-independent growth. This suggests that MED19 cooperates with ELK1 to regulate AR occupancy and H3K27 acetylation at MAOA, upregulating its expression and driving androgen independence in prostate cancer cells. This study provides important insight into the mechanisms of prostate cancer cell growth under low androgen, and underscores the importance of the MED19-MAOA axis in this process.

Hypoxia Increases Androgen Receptor Activity in Prostate Cancer Cells

2006 ◽  
Vol 66 (10) ◽  
pp. 5121-5129 ◽  
Author(s):  
Soo-Yeon Park ◽  
Yun-Jeong Kim ◽  
Allen C. Gao ◽  
James L. Mohler ◽  
Sergio A. Onate ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Androgen Receptor ◽  
Cancer Cells ◽  
Receptor Activity ◽  
Prostate Cancer Cells ◽  
Androgen Receptor Activity

Phenethyl isothiocyanate in combination with dibenzoylmethane inhibits the androgen-independent growth of prostate cancer cells

2018 ◽  
Vol 9 (4) ◽  
pp. 2398-2408 ◽  
Author(s):  
Huarong Huang ◽  
Yan He ◽  
Lanyue Zhang ◽  
Hongping Xiang ◽  
Dongli Li ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Cancer Cells ◽  
Inhibitory Effect ◽  
Phenethyl Isothiocyanate ◽  
Prostate Cancer Cells ◽  
Prostate Tumors ◽  
Androgen Independence ◽  
Androgen Independent

This study investigates the inhibitory effect of PEITC and DBM in combination on the progression of androgen-dependent VCaP prostate tumors to androgen independence.

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