GABBR2 as a Downstream Effector of the Androgen Receptor Induces Cisplatin Resistance in Bladder Cancer

The precise molecular mechanisms responsible for resistance to cisplatin-based chemotherapy in patients with bladder cancer remain elusive, while we have indicated that androgen receptor (AR) activity in urothelial cancer is associated with its sensitivity. Our DNA microarray analysis in control vs. AR-knockdown bladder cancer sublines suggested that the expression of a GABA B receptor GABBR2 and AR was correlated. The present study aimed to determine the functional role of GABBR2 in modulating cisplatin sensitivity in bladder cancer. AR knockdown and dihydrotestosterone treatment considerably reduced and induced, respectively, GABBR2 expression, and the effect of dihydrotestosterone was at least partially restored by an antiandrogen hydroxyflutamide. A chromatin immunoprecipitation assay further revealed the binding of AR to the promoter region of GABBR2 in bladder cancer cells. Meanwhile, GABBR2 expression was significantly elevated in a cisplatin-resistant bladder cancer subline, compared with control cells. In AR-positive bladder cancer cells, knockdown of GABBR2 or treatment with a selective GABA B receptor antagonist, CGP46381, considerably enhanced the cytotoxic activity of cisplatin. However, no additional effect of CGP46381 on cisplatin-induced growth suppression was seen in GABBR2-knockdown cells. Moreover, in the absence of cisplatin, CGP46381 treatment and GABBR2 knockdown showed no significant changes in cell proliferation or migration. These findings suggest that GABBR2 represents a key downstream effector of AR signaling in inducing resistance to cisplatin treatment. Accordingly, inhibition of GABBR2 has the potential of being a means of chemosensitization, especially in patients with AR/GABBR2-positive bladder cancer.

[1]  I. Bodrogi,et al.  Gemcitabine and Cisplatin Versus Methotrexate, Vinblastine, Doxorubicin, and Cisplatin in Advanced or Metastatic Bladder Cancer: Results of a Large, Randomized, Multinational, Multicenter, Phase III Study. , 2023, Journal of clinical oncology : official journal of the American Society of Clinical Oncology.

[2]  M. Gingras,et al.  γ-aminobutyric acid B2 receptor: A potential therapeutic target for cholangiocarcinoma in patients with diabetes mellitus , 2023, World journal of gastroenterology.

[3]  P. Gajate,et al.  Current and Future Landscape of Perioperative Treatment for Muscle-Invasive Bladder Cancer , 2023, Cancers.

[4]  Sujin Choi,et al.  miR-31-3p functions as a tumor suppressor by directly targeting GABBR2 in prostate cancer , 2022, Frontiers in Oncology.

[5]  R. Santi,et al.  Neoadjuvant Treatment in Muscle-Invasive Bladder Cancer: From the Beginning to the Latest Developments , 2022, Frontiers in Oncology.

[6]  Zhiquan Hu,et al.  Circular RNAs and Drug Resistance in Genitourinary Cancers: A Literature Review , 2022, Cancers.

[7]  G. Netto,et al.  Androgen Receptor Signaling Induces Cisplatin Resistance via Down-Regulating GULP1 Expression in Bladder Cancer , 2021, International journal of molecular sciences.

[8]  V. Cherezov,et al.  Molecular mechanisms of metabotropic GABAB receptor function , 2021, Science Advances.

[9]  H. Ide,et al.  Sex Hormone Receptor Signaling in Bladder Cancer: A Potential Target for Enhancing the Efficacy of Conventional Non-Surgical Therapy , 2021, Cells.

[10]  P. Tchounwou,et al.  Advances in Our Understanding of the Molecular Mechanisms of Action of Cisplatin in Cancer Therapy , 2021, Journal of experimental pharmacology.

[11]  S. Inoue,et al.  Identification of BXDC2 as a Key Downstream Effector of the Androgen Receptor in Modulating Cisplatin Sensitivity in Bladder Cancer , 2021, Cancers.

[12]  S. Shariat,et al.  Update on systemic treatment of upper tract urothelial carcinoma: a narrative review of the literature , 2021, Translational andrology and urology.

[13]  A. Hamid,et al.  Meta-analysis of neoadjuvant chemotherapy compared to radical cystectomy alone in improving overall survival of muscle-invasive bladder cancer patients , 2020, BMC Urology.

[14]  S. Inoue,et al.  Androgen Receptor Signaling Reduces the Efficacy of Bacillus Calmette-Guérin Therapy for Bladder Cancer via Modulating Rab27b-Induced Exocytosis , 2020, Molecular Cancer Therapeutics.

[15]  S. Inoue,et al.  FOXO1 inactivation induces cisplatin resistance in bladder cancer , 2020, Cancer science.

[16]  Xiaoping Zhou,et al.  ceRNA network development and tumour-infiltrating immune cell analysis of metastatic breast cancer to bone , 2020, Journal of bone oncology.

[17]  Hongjun Li,et al.  miRNAs: A Promising Target in the Chemoresistance of Bladder Cancer , 2019, OncoTargets and therapy.

[18]  L. Smit,et al.  Multicenter Validation of Histopathologic Tumor Regression Grade After Neoadjuvant Chemotherapy in Muscle-invasive Bladder Carcinoma , 2019, The American journal of surgical pathology.

[19]  M. Ankem,et al.  Combination of androgen receptor inhibitor and cisplatin, an effective treatment strategy for urothelial carcinoma of the bladder. , 2019, Urologic oncology.

[20]  Tetsutaro Hayashi,et al.  Transcribed ultraconserved region Uc.63+ promotes resistance to cisplatin through regulation of androgen receptor signaling in bladder cancer. , 2019, Oncology reports.

[21]  K. Hanna Updates and novel treatments in urothelial carcinoma , 2018, Journal of oncology pharmacy practice : official publication of the International Society of Oncology Pharmacy Practitioners.

[22]  A. Jemal,et al.  Global cancer statistics 2018: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries , 2018, CA: a cancer journal for clinicians.

[23]  S. Uddin,et al.  Cisplatin based therapy: the role of the mitogen activated protein kinase signaling pathway , 2018, Journal of Translational Medicine.

[24]  H. Fröhlich,et al.  Key Players of Cisplatin Resistance: Towards a Systems Pharmacology Approach , 2018, International journal of molecular sciences.

[25]  Steven J. M. Jones,et al.  Comprehensive Molecular Characterization of Muscle-Invasive Bladder Cancer , 2017, Cell.

[26]  Jianfeng Liu,et al.  GABABR-Induced EGFR Transactivation Promotes Migration of Human Prostate Cancer Cells , 2017, Molecular Pharmacology.

[27]  S. Inoue,et al.  Role of the androgen receptor in urothelial cancer , 2017, Molecular and Cellular Endocrinology.

[28]  Yun Liu,et al.  Genome-wide DNA Methylation Analysis Reveals GABBR2 as a Novel Epigenetic Target for EGFR 19 Deletion Lung Adenocarcinoma with Induction Erlotinib Treatment , 2017, Clinical Cancer Research.

[29]  S. Inoue,et al.  Androgen receptor activity modulates responses to cisplatin treatment in bladder cancer , 2016, Oncotarget.

[30]  M. Babjuk,et al.  European Association of Urology Guidelines on Upper Urinary Tract Urothelial Carcinoma: 2017 Update. , 2015, European urology.

[31]  A. Jemal,et al.  Global cancer statistics, 2012 , 2015, CA: a cancer journal for clinicians.

[32]  Yair Lotan,et al.  Multicenter assessment of neoadjuvant chemotherapy for muscle-invasive bladder cancer. , 2015, European urology.

[33]  Yi Li,et al.  GATA3 in the urinary bladder: suppression of neoplastic transformation and down-regulation by androgens. , 2014, American journal of cancer research.

[34]  Chih Lee,et al.  LASAGNA-Search 2.0: integrated transcription factor binding site search and visualization in a browser , 2014, Bioinform..

[35]  Jingxin Li,et al.  GABAergic signaling facilitates breast cancer metastasis by promoting ERK1/2-dependent phosphorylation. , 2014, Cancer letters.

[36]  L. Galluzzi,et al.  Systems biology of cisplatin resistance: past, present and future , 2014, Cell Death and Disease.

[37]  K. Baggerly,et al.  Identification of distinct basal and luminal subtypes of muscle-invasive bladder cancer with different sensitivities to frontline chemotherapy. , 2014, Cancer cell.

[38]  Haibo Zhang,et al.  Expression of gamma-aminobutyric acid receptors on neoplastic growth and prediction of prognosis in non-small cell lung cancer , 2013, Journal of Translational Medicine.

[39]  K. Kuroiwa,et al.  Androgen receptor signaling regulates cell growth and vulnerability to doxorubicin in bladder cancer. , 2012, The Journal of urology.

[40]  Mårten Fernö,et al.  A Molecular Taxonomy for Urothelial Carcinoma , 2012, Clinical Cancer Research.

[41]  Jorge Yao,et al.  Dihydrotestosterone upregulates the expression of epidermal growth factor receptor and ERBB2 in androgen receptor-positive bladder cancer cells. , 2011, Endocrine-related cancer.

[42]  G. Minuk,et al.  GABA-B receptor activation inhibits the in vitro migration of malignant hepatocytes. , 2011, Canadian journal of physiology and pharmacology.

[43]  S. Roberts,et al.  GABA Receptor Expression in Benign and Malignant Thyroid Tumors , 2009, Pathology & Oncology Research.

[44]  N. Hoosein,et al.  Expression of gamma-aminobutyric acid receptor (subtype A) in prostate cancer , 2008, Acta oncologica.

[45]  Masahito Watanabe,et al.  Invasive Ability of Human Renal Cell Carcinoma Cell Line Caki-2 Is Accelerated by Gamma-Aminobutyric Acid, via Sustained Activation of ERK1/2 Inducible Matrix Metalloproteinases , 2007, Cancer investigation.

[46]  T. Patel,et al.  gamma-Aminobutyric acid inhibits cholangiocarcinoma growth by cyclic AMP-dependent regulation of the protein kinase A/extracellular signal-regulated kinase 1/2 pathway. , 2005, Cancer research.

[47]  M. Lai,et al.  Various forms of mutant p53 confer sensitivity to cisplatin and doxorubicin in bladder cancer cells. , 2001, The Journal of urology.

[48]  W. Froestl,et al.  The actions of orally active GABAB receptor antagonists on GABAergic transmission in vivo and in vitro. , 1993, European journal of pharmacology.

[49]  D. Kelsen,et al.  Cisplatin nephrotoxicity. Correlation with plasma platinum concentrations. , 1985, American journal of clinical oncology.

[50]  T. Miyazaki,et al.  Enzalutamide inhibits proliferation of gemcitabine-resistant bladder cancer cells with increased androgen receptor expression. , 2017, International journal of oncology.

[51]  F. Entschladen,et al.  The neurotransmitter gamma-aminobutyric acid is an inhibitory regulator for the migration of SW 480 colon carcinoma cells. , 2002, Cancer research.