USP8 inhibitor RA-9 reduces ACTH release and cell growth in tumor corticotrophs

2021 ◽  
Author(s):  
Donatella Treppiedi ◽  
Genesio Di Muro ◽  
Giusy Marra ◽  
Anna Maria Barbieri ◽  
Federica Mangili ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Primary Cultures ◽  
Hormone Secretion ◽  
Human Tumor ◽  
Wild Type ◽  
Acth Secretion ◽  
Curative Therapy ◽  
Novel Strategy ◽  
Acth Secreting

Cushing’s Disease (CD) is a rare endocrine disorder caused by an adrenocorticotropic hormone (ACTH)-secreting pituitary tumor. Pasireotide is the only pituitary-targeted drug approved for adult patients. Nevertheless, many side effects are encountered and a curative therapy is still challenging. Ubiquitin Specific Peptidase 8 (USP8) plays a crucial role in the modulation of corticotroph cells growth and ACTH secretion. Here, we explored the anticancer potential of the USP8 inhibitor RA-9 in USP8-wild type human tumor corticotroph cells and murine AtT-20 cells. Our results showed that RA-9 causes cell proliferation decrease (-24.3±5.2%, P<0.01) and cell apoptosis increase (207.4±75.3%, P<0.05) in AtT-20 cells, as observed with pasireotide. Moreover, RA-9 reduced ACTH secretion in AtT-20 cells (-34.1±19.5%,P<0.01), as well as in AtT-20 cells transfected with USP8 mutants, and in 1 out of 2 primary cultures in vitro responsive to pasireotide (-40.3±6%). A RA-9 mediated decrease of pERK1/2 levels was observed in AtT-20 cells (-52.3±13.4%, P<0.001), comparable to pasireotide, and in primary cultures, regardless of their in vitro responsiveness to pasireotide. Upregulation of p27 was detected upon RA-9 treatment only, both in AtT-20 cells (167.1±36.7%, P<0.05) and 1 primary culture tested (168.4%), whilst pCREB level was similarly halved in AtT-20 cells by both RA-9 and pasireotide. Altogether, our data demonstrate that RA-9 is efficient in exerting cytotoxic effects and inhibitory actions on cell proliferation and hormone secretion by modulating the expression of pERK1/2, pCREB and p27. Inhibition of USP8 might represent a novel strategy to target both USP8-wild type and USP8-mutated tumors in CD patients.

Gap junction expression and cell proliferation in differentiating cultures of Cx43 KO mouse hepatocytes

2001 ◽  
Vol 281 (4) ◽  
pp. G1004-G1013 ◽  
Author(s):  
Takashi Kojima ◽  
Alfredo Fort ◽  
Mingyuan Tao ◽  
Masao Yamamoto ◽  
David C. Spray
Keyword(s):  
Lucifer Yellow ◽  
Primary Cultures ◽  
Mrna Levels ◽  
Wild Type ◽  
Dye Transfer ◽  
Gap Junctional Communication ◽  
Junctional Communication ◽  
Junctional Conductance ◽  
Mouse Hepatocytes

Primary cultures of adult mouse hepatocytes are shown here to reexpress differentiated hepatocyte features following treatment with 2% DMSO and 10−7 M glucagon. To examine the roles of gap junctional communication during hepatocyte growth and differentiation, we have compared treated and untreated hepatocytes from connexin (Cx)32-deficient [Cx32 knockout (KO)] and wild-type mice. In untreated cultures, DNA replication of Cx32 KO hepatocytes was markedly higher than of wild types. Although Cx26 mRNA levels remained high at all time points in wild-type and Cx32 KO hepatocytes, Cx32 mRNA and protein in wild-type hepatocytes underwent a marked decline, which recovered in 10-day treated cultures. Increased levels of Cx26 protein and junctional conductance were observed in Cx32 KO hepatocytes at 96 h in culture, a time when cell growth rate was high. Treatment with DMSO/glucagon highly reinduced Cx26 expression in Cx32 KO hepatocytes, and such treatment reinduced expression of both Cx32 and Cx26 expression in wild types. Dye transfer was not observed following Lucifer yellow injection into DMSO/glucagon-treated Cx32 KO hepatocytes, whereas the spread was extensive in wild types. Nevertheless, high junctional conductance values were observed in treated cells from both genotypes. These studies provide a method by which the differentiated phenotype can be obtained in cultured mouse hepatocytes and provide in vitro evidence that expression of gap junctions formed of Cx32 are involved in the regulation of growth of mouse hepatocytes.

scholarly journals Ubiquitin-Specific Protease 8 Mutant Corticotrope Adenomas Present Unique Secretory and Molecular Features and Shed Light on the Role of Ubiquitylation on ACTH Processing

2019 ◽  
Vol 110 (1-2) ◽  
pp. 119-129 ◽  
Author(s):  
Antonella Sesta ◽  
Maria Francesca Cassarino ◽  
Mariarosa Terreni ◽  
Alberto G. Ambrogio ◽  
Laura Libera ◽  
...  
Keyword(s):  
Protein Degradation ◽  
Pituitary Adenomas ◽  
Expression Profiles ◽  
Primary Cultures ◽  
Acth Secretion ◽  
Specific Protease ◽  
Ubiquitin Proteasome ◽  
Ubiquitin Specific Protease ◽  
Acth Secreting

Background: Somatic mutations in the ubiquitin-specific protease 8 (USP8) gene have recently been shown to occur in ACTH-secreting pituitary adenomas, thus calling attention to the ubiquitin system in corticotrope adenomas. Objectives: Assess the consequences of USP8 mutations and establish the role of ubiquitin on ACTH turnover in human ACTH-secreting pituitary adenomas. Methods: USP8 mutation status was established in 126 ACTH-secreting adenomas. Differences in ACTH secretion and POMC expression from adenoma primary cultures and in microarray gene expression profiles from archival specimens were sought according to USP8 sequence. Ubiquitin/ACTH coimmunoprecipitation and incubation with MG132, a proteasome inhibitor, were performed in order to establish whether ubiquitin plays a role in POMC/ACTH degradation in corticotrope adenomas. Results: USP8 mutations were identified in 29 adenomas (23%). Adenomas presenting USP8 mutations secreted greater amounts of ACTH and expressed POMC at higher levels compared to USP wild-type specimens. USP8 mutant adenomas were also more sensitive to modulation by CRH and dexamethasone in vitro. At microarray analysis, genes associated with endosomal protein degradation and membrane components were downregulated in USP8 mutant adenomas as were AVPR1B, IL11RA, and PITX2. Inhibition of the ubiquitin-proteasome pathway increased ACTH secretion and POMC itself proved a target of ubiquitylation, independently of USP8 sequence status. Conclusions: Our study has shown that USP8 mutant ACTH-secreting adenomas present a more “typical” corticotrope phenotype and reduced expression of several genes associated with protein degradation. Further, ubiquitylation is directly involved in intracellular ACTH turnover, suggesting that the ubiquitin-proteasome system may represent a target for treatment of human ACTH-secreting adenomas.

Differential in vitro effects of chemotherapeutic agents on primary cultures of human ovarian carcinoma

2004 ◽  
Vol 14 (4) ◽  
pp. 607-615 ◽  
Author(s):  
P. Kornblith ◽  
R. L. Ochs ◽  
A. Wells ◽  
M. J. Gabrin ◽  
J. Piwowar ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Cultured Cells ◽  
Primary Cultures ◽  
Human Tumor ◽  
Clinical Results ◽  
Chemotherapeutic Agents ◽  
Primary Ovarian Cancer ◽  
In Vitro Effects ◽  
Therapeutic Decision Making

The treatment of ovarian cancer principally relies on the use of platinum and taxane chemotherapeutic agents. Short-term clinical results have been encouraging, but long-term responses remain limited. In this report, an in vitro assay system that utilizes cells grown from human tumor explants has been used to quantitatively evaluate responses to relevant concentrations of alternative chemotherapeutic agents. The results suggest that there are significant differences in the responses of explant-derived cultured cells to the different agents tested. In an evaluation of 276 primary ovarian cancer specimens, five nonstandard drugs were tested in 51 cases. Of these 51 cases, cyclophosphamide had the highest rate of response at 67%, followed by doxorubicin at 61%, gemcitabine at 49%, etoposide at 48%, and topotecan at 14%. Venn diagrams, representing the in vitro responses to the platins and taxanes, as well as the responses to the nonstandard drugs, illustrate that there clearly are distinct differences among patients in a given population. These data underscore the potential importance of evaluating each patient's response to a number of different drugs to optimize the therapeutic decision-making process.

scholarly journals Keratin 17 regulates nuclear morphology and chromatin organization

2020 ◽  
Vol 133 (20) ◽  
pp. jcs254094 ◽  
Author(s):  
Justin T. Jacob ◽  
Raji R. Nair ◽  
Brian G. Poll ◽  
Christopher M. Pineda ◽  
Ryan P. Hobbs ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Proliferation ◽  
Target Genes ◽  
Primary Cultures ◽  
Human Tumor ◽  
Chromatin Organization ◽  
Nuclear Morphology ◽  
Intermediate Filament Protein ◽  
Mutant Form ◽  
Keratin 17

ABSTRACTKeratin 17 (KRT17; K17), a non-lamin intermediate filament protein, was recently found to occur in the nucleus. We report here on K17-dependent differences in nuclear morphology, chromatin organization, and cell proliferation. Human tumor keratinocyte cell lines lacking K17 exhibit flatter nuclei relative to normal. Re-expression of wild-type K17, but not a mutant form lacking an intact nuclear localization signal (NLS), rescues nuclear morphology in KRT17-null cells. Analyses of primary cultures of skin keratinocytes from a mouse strain expressing K17 with a mutated NLS corroborated these findings. Proteomics screens identified K17-interacting nuclear proteins with known roles in gene expression, chromatin organization and RNA processing. Key histone modifications and LAP2β (an isoform encoded by TMPO) localization within the nucleus are altered in the absence of K17, correlating with decreased cell proliferation and suppression of GLI1 target genes. Nuclear K17 thus impacts nuclear morphology with an associated impact on chromatin organization, gene expression, and proliferation in epithelial cells.This article has an associated First Person interview with the first author of the paper.

scholarly journals Mitotane reduces human and mouse ACTH-secreting pituitary cell viability and function

2013 ◽  
Vol 218 (3) ◽  
pp. 275-285 ◽  
Author(s):  
Erica Gentilin ◽  
Federico Tagliati ◽  
Massimo Terzolo ◽  
Matteo Zoli ◽  
Marcello Lapparelli ◽  
...  
Keyword(s):  
Cell Viability ◽  
Cell Line ◽  
Primary Cultures ◽  
Pituitary Cell ◽  
Therapeutic Window ◽  
Adrenocortical Function ◽  
Acth Secretion ◽  
And Function ◽  
Acth Secreting ◽  
Human And Mouse

Medical therapy for Cushing's disease (CD) is currently based on agents mainly targeting adrenocortical function. Lately, pituitary-directed drugs have been developed, with limited efficacy. Mitotane, a potent adrenolytic drug, has been recently investigated for the treatment of CD, but the direct pituitary effects have not been clarified so far. The aim of our study was to investigate whether mitotane may affect corticotroph function and cell survival in the mouse pituitary cell line AtT20/D16v-F2 and in the primary cultures of human ACTH-secreting pituitary adenomas, as an in vitro model of pituitary corticotrophs. We found that in the AtT20/D16v-F2 cell line and in primary cultures, mitotane reduces cell viability by inducing caspase-mediated apoptosis and reduces ACTH secretion. In the AtT20/D16v-F2 cell line, mitotane reduces Pomc expression and blocks the stimulatory effects of corticotropin-releasing hormone on cell viability, ACTH secretion, and Pomc expression. These effects were apparent at mitotane doses greater than those usually necessary for reducing cortisol secretion in Cushing's syndrome, but still in the therapeutic window for adrenocortical carcinoma treatment. In conclusion, our results demonstrate that mitotane affects cell viability and function of human and mouse ACTH-secreting pituitary adenoma cells. These data indicate that mitotane could have direct pituitary effects on corticotroph cells.

scholarly journals Regulation of cell proliferation by ERK and signal-dependent nuclear translocation of ERK is dependent on Tm5NM1-containing actin filaments

2015 ◽  
Vol 26 (13) ◽  
pp. 2475-2490 ◽  
Author(s):  
Galina Schevzov ◽  
Anthony J. Kee ◽  
Bin Wang ◽  
Vanessa B. Sequeira ◽  
Jeff Hook ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Actin Filaments ◽  
Nuclear Translocation ◽  
Genetic Manipulation ◽  
Wild Type ◽  
Proximity Ligation ◽  
Mouse Embryo Fibroblasts ◽  
Wild Type Mefs

ERK-regulated cell proliferation requires multiple phosphorylation events catalyzed first by MEK and then by casein kinase 2 (CK2), followed by interaction with importin7 and subsequent nuclear translocation of pERK. We report that genetic manipulation of a core component of the actin filaments of cancer cells, the tropomyosin Tm5NM1, regulates the proliferation of normal cells both in vitro and in vivo. Mouse embryo fibroblasts (MEFs) lacking Tm5NM1, which have reduced proliferative capacity, are insensitive to inhibition of ERK by peptide and small-molecule inhibitors, indicating that ERK is unable to regulate proliferation of these knockout (KO) cells. Treatment of wild-type MEFs with a CK2 inhibitor to block phosphorylation of the nuclear translocation signal in pERK resulted in greatly decreased cell proliferation and a significant reduction in the nuclear translocation of pERK. In contrast, Tm5NM1 KO MEFs, which show reduced nuclear translocation of pERK, were unaffected by inhibition of CK2. This suggested that it is nuclear translocation of CK2-phosphorylated pERK that regulates cell proliferation and this capacity is absent in Tm5NM1 KO cells. Proximity ligation assays confirmed a growth factor–stimulated interaction of pERK with Tm5NM1 and that the interaction of pERK with importin7 is greatly reduced in the Tm5NM1 KO cells.

In Vitro Evaluation of Plasticizer Activity on the Growth and Metabolism of Chick Embryo Fibroblasts and on the Development of Chick Embryo Lungs

1992 ◽  
Vol 20 (6) ◽  
pp. 475-482 ◽  
Author(s):  
G Stabellini ◽  
O Fiocchi ◽  
A Pellati ◽  
A Caruso
Keyword(s):  
Cell Proliferation ◽  
Protein Synthesis ◽  
Chick Embryo ◽  
Primary Cultures ◽  
Embryonic Cells ◽  
Cytostatic Effect ◽  
Dna And Protein Synthesis ◽  
Embryo Fibroblasts ◽  
Ethylhexyl Phthalate

Administration of di(2-ethylhexyl) phthalate (DEHP) to primary cultures of chick embryo fibroblasts brought about a decrease in cell proliferation rate after 48 h and an inhibition of both DNA and protein synthesis measured by [3H]thymidine and [3H]leucine, respectively, after 48h. The growth of chick embryo lung rudiments in vitro was also depressed by DEHP treatment. Lung rudiment were smaller in DEHP-treated embryos after 6 days' treatment. These results indicate that DEHP has a cytostatic effect on embryonic cells and tissues. L'administration de di(2-éthylhexyl) phthalate (DEHP) à des cultures primaires de fibroblastes d'embryon de poulet a provoqué une diminution du taux de prolifération cellulaire après 48 heures et une inhibition de la synthèse à la fois d'ADN et de protéines mesurée, respectivement, par [3H]thymidine et [3H]leucine après 48 h. La croissance des ébauches pulmonaires de l'embryon de poulet in vitro a également été abaissée par le traitement DEHP. Les ébauches pulmonaires étaient plus petites dans les embryons traités au DEHP après un traitement de 6 jours. Ces résultats indiquent que le DEHP a un effet cytostatique sur les cellules et tissus embryonnaires.

In Vitro Effects of Glycosphingolipids on Human Tumor Cell Proliferation

1981 ◽  
Vol 166 (1) ◽  
pp. 107-112 ◽  
Author(s):  
P. M. Kimball ◽  
L. Hammonds ◽  
J. M. McKibbin ◽  
M. G. Brattain ◽  
G. Glover ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Tumor Cell ◽  
Human Tumor ◽  
Tumor Cell Proliferation ◽  
Human Tumor Cell ◽  
In Vitro Effects

Ghrelin Stimulates Adrenocorticotrophic Hormone (ACTH) Secretion by Human ACTH-Secreting Pituitary Adenomas In Vitro

2007 ◽  
Vol 19 (3) ◽  
pp. 208-212 ◽  
Author(s):  
F. Pecori Giraldi ◽  
L. G. Bucciarelli ◽  
A. Saccani ◽  
M. Scacchi ◽  
S. Pesce ◽  
...  
Keyword(s):  
Pituitary Adenomas ◽  
Adrenocorticotrophic Hormone ◽  
Acth Secretion ◽  
Acth Secreting

Poly(ADP-ribose) polymerase-1 (PARP-1) controls lung cell proliferation and repair after hyperoxia-induced lung damage

2007 ◽  
Vol 293 (3) ◽  
pp. L619-L629 ◽  
Author(s):  
Alessandra Pagano ◽  
Isabelle Métrailler-Ruchonnet ◽  
Michel Aurrand-Lions ◽  
Monica Lucattelli ◽  
Yves Donati ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Cell Damage ◽  
Neutrophil Infiltration ◽  
Lung Damage ◽  
Wild Type ◽  
Cell Hyperplasia ◽  
Primary Fibroblasts ◽  
Parp 1

Oxygen-based therapies expose lung to elevated levels of ROS and induce lung cell damage and inflammation. Injured cells are replaced through increased proliferation and differentiation of epithelial cells and fibroblasts. Failure to modulate these processes leads to excessive cell proliferation, collagen deposition, fibrosis, and chronic lung disease. Poly(ADP-ribose) polymerase-1 (PARP-1) is activated in response to DNA damage and participates in DNA repair, genomic integrity, and cell death. In this study, we evaluated the role of PARP-1 in lung repair during recovery after acute hyperoxia exposure. We exposed PARP-1 −/− and wild-type mice for 64 h to 100% hyperoxia and let them recover in air for 5–21 days. PARP-1-deficient mice exhibited significantly higher lung cell hyperplasia and proliferation than PARP-1 +/+ animals after 5 and 10 days of recovery. This was accompanied by an increased inflammatory response in PARP-1 −/− compared with wild-type animals, characterized by neutrophil infiltration and increased IL-6 levels in bronchoalveolar lavages. These lesions were reversible, since the extent of the hyperplastic regions was reduced after 21 days of recovery and did not result in fibrosis. In vitro, lung primary fibroblasts derived from PARP-1 −/− mice showed a higher proliferative response than PARP-1 +/+ cells during air recovery after hyperoxia-induced growth arrest. Altogether, these results reveal an essential role of PARP-1 in the control of cell repair and tissue remodeling after hyperoxia-induced lung injury.

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