Search Results

You are looking at 1 - 1 of 1 items for

  • Author: Federica Mangili x
  • All content x
Clear All Modify Search
Restricted access

Donatella Treppiedi, Genesio Di Muro, Giusy Marra, Anna Maria Barbieri, Federica Mangili, Rosa Catalano, Andreea Liliana Serban, Emanuele Ferrante, Marco Locatelli, Andrea Gerardo Antonio Lania, Maura Arosio, Anna Spada, Erika Peverelli, and Giovanna Mantovani

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.