Preproorexin and Orexin Receptors Are Expressed in Cortisol-Secreting Adrenocortical Adenomas, and Orexins Stimulate in Vitro Cortisol Secretion and Growth of Tumor Cells

Spinazzi, Raffaella; Ruciński, Marcin; Neri, Giuliano; Malendowicz, L K; Nussdorfer, Gastone G.

doi:10.1210/jc.2004-2385

Cited by 53 publications

(86 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this study, we have measured a direct functional outcome of steroidogenesis and cortisol secretion. Cortisol is known to increase in primary adrenal cells and ex vivo tissue in response to ORA (Spinazzi et al 2005a). In our H295R cells, this occurred significantly for ORA but not ORB, consistent with the primary cell and ex vivo data.…”

Section: Discussionsupporting

confidence: 90%

“…Expression of both orexin receptor subtypes has been shown in both the human and rodent adrenal gland (Sakurai et al 1998, Johren et al 2001, Spinazzi et al 2005a. These receptors couple to multiple G-proteins and activate intracellular signalling pathways within the adrenal gland , Malendowicz et al 2001 leading to the production of both cAMP and inositol trisphosphate (IP 3 ) in human adrenal cells .…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Orexin-stimulated MAP kinase cascades are activated through multiple G-protein signalling pathways in human H295R adrenocortical cells: diverse roles for orexins A and B

Ramanjaneya¹,

Conner²,

Chen³

et al. 2009

Journal of Endocrinology

View full text Add to dashboard Cite

Orexins A and B (ORA and ORB) are neuropeptide hormones found throughout the central nervous system and periphery. They are required for a host of physiological processes including mitogen-activated protein kinase (MAPK) regulation, steroidogenesis, appetite control and energy regulation. While some signalling mechanisms have been proposed for individual recombinant orexin receptors in generic mammalian cell types, it is clear that the peripheral effects of orexin are spatially and temporally complex. This study dissects the different G-protein signalling and MAPK pathways activated in a pluripotent human adrenal H295R cell line capable of all the physiological steps involved in steroidogenesis. Both extracellular receptor kinase 1/2 (ERK1/2) and p38 were phosphorylated rapidly with a subsequent decline, in a time-and dose-dependent manner, in response to both ORA and ORB. Conversely, there was little or no direct activation of the ERK5 or JNK pathway. Analysis using signalling and MAPK inhibitors as well as receptorspecific antagonists determined the precise mediators of the orexin response in these cells. Both ERK1/2 and p38 activation were predominantly G q -and to a lesser extent G s -mediated; p38 activation even had a small G i -component. Effects were broadly comparable for both orexin sub-types ORA and ORB and although most of the effects were transmitted through the orexin receptor-1 subtype, we did observe a role for orexin receptor-2-mediated activation of both ERK1/2 and p38. Cortisol secretion also differed in response to ORA and ORB. These data suggest multiple roles for orexin-mediated MAPK activation in an adrenal cell-line, this complexity may help to explain the diverse biological actions of orexins with wide-ranging consequences for our understanding of the mechanisms initiated by these steroidogenic molecules.

show abstract

Section: Discussionsupporting

confidence: 90%

Section: Introductionmentioning

confidence: 99%

Orexin-stimulated MAP kinase cascades are activated through multiple G-protein signalling pathways in human H295R adrenocortical cells: diverse roles for orexins A and B

Ramanjaneya¹,

Conner²,

Chen³

et al. 2009

Journal of Endocrinology

View full text Add to dashboard Cite

show abstract

“…Dispersed cells were lysed, proteins were extracted from each lysate in sample buffer containing protease inhibitors, and 100 μg of proteins was subjected to SDS-PAGE under reducing conditions, as detailed previously (18,19). Samples were resolved in a standard gel apparatus and then transferred to nitrocellulose membranes (SigmaAldrich Corp.).…”

Section: Rt-pcrmentioning

confidence: 99%

“…Cell preparations from adrenals 17-20 were preincubated with Ptx (0.5 μg/ml) for 180 min; then the medium was discarded and cells were exposed for 60 min to a fresh one containing or not 10 -8 M galanin. The concentrations of anti-galanin receptor antibodies and signaling cascade inhibitors were those used in previous investigations (7,18,20). The incubations were carried out in a shaking bath at 37˚C for 60 min (cortisol secretion) or 10 min (cAMP and IP3 production) in an atmosphere of 95% air-5% CO 2 .…”

Section: Rt-pcrmentioning

confidence: 99%

Galanin stimulates cortisol secretion from human adrenocortical cells through the activation of galanin receptor subtype 1 coupled to the adenylate cyclase-dependent signaling cascade

Belloni

Malendowicz²,

Ruciński³

et al. 2007

Int J Mol Med

View full text Add to dashboard Cite

Abstract. Previous studies showed that galanin receptors are expressed in the rat adrenal, and galanin modulates glucocorticoid secretion in this species. Hence, we investigated the expression of the various galanin receptor subtypes (GAL-R1, GAL-R2 and GAL-R3) in the human adrenocortical cells, and the possible involvement of galanin in the control of cortisol secretion. Reverse transcription-polymerase chain reaction detected the expression of GAL-R1 (but not GAL-R2 and GAL-R3) in the inner zones of the human adrenal cortex. The galanin concentration dependently enhanced basal, but not ACTH-stimulated secretion of cortisol from dispersed inner adrenocortical cells (maximal effective concentration, 10 -8 M). The cortisol response to 10 -8 M galanin was abrogated by GAL-R1 immunoneutralization, and unaffected by GAL-R2 or GAL-R3 immunoneutralization. Galanin (10 -8 M) and ACTH (10 -9 M) enhanced cyclic-AMP production from dispersed cells, and the response was suppressed by the adenylate cyclase inhibitor SQ-22536 (10 -4 M). Galanin did not affect inositol triphosphate release, which, in contrast, was raised by angiotensin-II (10 -8 M). SQ-22536 and the protein kinase (PK)A inhibitor H-89 (10 -5 M) abolished the cortisol response to 10 -8 M galanin, while the phospholipase C inhibitor U-73122 and the PKC inhibitor calphostin-C were ineffective. Preincubation with pertussis toxin (Ptx) (0.5 μg/ml) partially inhibited the cortisol response to galanin. We conclude that galanin stimulates cortisol secretion from human inner adrenocortical cells, acting through GAL-R1 coupled to the adenylate cyclase/PKA-dependent signaling cascade via a Ptx-sensitive Gα protein.

show abstract

“…The expression of OX1R has been found in cell lines from human colon cancer (17). However, the study pertaining to the expression of OX2R is limited to clinical samples of cortisol-secreting adrenocortical adenomas (18). Moreover, the role of orexin receptors in cancer cells is as yet unknown.…”

Section: Introductionmentioning

confidence: 99%

Orexin 2 receptor as a potential target for immunotoxin and antibody-drug conjugate cancer therapy

et al. 2011

View full text Add to dashboard Cite

Abstract. Targeting tumor-specific receptors is a promising approach for cytotoxic agents. The orexin 2 receptor (OX2R) has reportedly been expressed in a few types of cancer, but not in normal, cells. This study aimed to explore and assess the expression levels of OX2R in a wide range of cancer cell lines and clinical samples to identify its localization. To analyze OX2R expression, we developed a polyclonal antibody specific to OX2R by immunizing two rabbits with a peptide cocktail. A total of 36 cancer cell lines were employed for reverse transcription polymerase chain reaction (RT-PCR) and western blot analysis, and 221 samples from various tissue arrays were used for the immunohistochemistry of OX2R expression. OX2R was identified in three cancerous cell lines, from the gallbladder, squamous cell carcinoma of the head and neck (SCCHN) and glioblastoma. With clinical samples of tissue arrays, 69/221 (31.2%) samples reacted positively with the OX2R antibody. We confirmed its presence on the cell membrane. In conclusion, OX2R was identified on several cancer cells as well as clinical samples. Further studies with larger numbers of clinical samples are required to confirm the statistical significance of the presence and relationships of OX2R with tumor histology. Results of the current study suggested that OX2R is a potent target for immunotoxin or antibody-drug conjugate (ADC) cancer therapy on OX2R-positive cancer cells.

show abstract

Preproorexin and Orexin Receptors Are Expressed in Cortisol-Secreting Adrenocortical Adenomas, and Orexins Stimulate in Vitro Cortisol Secretion and Growth of Tumor Cells

Cited by 53 publications

References 28 publications

Orexin-stimulated MAP kinase cascades are activated through multiple G-protein signalling pathways in human H295R adrenocortical cells: diverse roles for orexins A and B

Orexin-stimulated MAP kinase cascades are activated through multiple G-protein signalling pathways in human H295R adrenocortical cells: diverse roles for orexins A and B

Galanin stimulates cortisol secretion from human adrenocortical cells through the activation of galanin receptor subtype 1 coupled to the adenylate cyclase-dependent signaling cascade

Orexin 2 receptor as a potential target for immunotoxin and antibody-drug conjugate cancer therapy

Contact Info

Product

Resources

About