Correction: Lycopene and Beta-Carotene Induce Growth Inhibition and Proapoptotic Effects on ACTH-Secreting Pituitary Adenoma Cells

Abstract The functional aftermath of microRNA (miRNA) dysregulation in ACTH-secreting pituitary adenomas has not been demonstrated. miRNAs represent diagnostic and prognostic biomarkers as well as putative therapeutic targets; their investigation may shed light on the mechanisms that underpin pituitary adenoma development and progression. Drugs interacting with such pathways may help in achieving disease control also in the settings of ACTH-secreting pituitary adenomas. We investigated the expression of 10 miRNAs among those that were found as most dysregulated in human pituitary adenoma tissues in the settings of a murine ACTH-secreting pituitary adenoma cell line, AtT20/D16v-F2. The selected miRNAs to be submitted to further investigation in AtT20/D16v-F2 cells represent an expression panel including 5 up-regulated and 5 down-regulated miRNAs. Among these, we selected the most dysregulated mouse miRNA and searched for miRNA targets and their biological function. We found that AtT20/D16v-F2 cells have a specific miRNA expression profile and that miR-26a is the most dysregulated miRNA. The latter is overexpressed in human pituitary adenomas and can control viable cell number in the in vitro model without involving caspase 3/7-mediated apoptosis. We demonstrated that protein kinase Cδ (PRKCD) is a direct target of miR-26a and that miR26a inhibition delays the cell cycle in G1 phase. This effect involves down-regulation of cyclin E and cyclin A expression via PRKCD modulation. miR-26a and related pathways, such as PRKCD, play an important role in cell cycle control of ACTH pituitary cells, opening new therapeutic possibilities for the treatment of persistent/recurrent Cushing's disease.

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Marked Response of a Hypermutated ACTH-Secreting Pituitary Carcinoma to Ipilimumab and Nivolumab

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2018-01347 ◽

2018 ◽

Vol 103 (10) ◽

pp. 3925-3930 ◽

Cited By ~ 37

Author(s):

Andrew L Lin ◽

Philip Jonsson ◽

Viviane Tabar ◽

T Jonathan Yang ◽

John Cuaron ◽

...

Keyword(s):

Pituitary Adenoma ◽

Liver Metastasis ◽

Effective Treatment ◽

Somatic Hypermutation ◽

Treatment Options ◽

Pituitary Tumors ◽

Pituitary Carcinoma ◽

Tumor Resistance ◽

Clinical Sequencing ◽

Acth Secreting

Abstract Context Pituitary carcinoma is a rare and aggressive malignancy with a poor prognosis and few effective treatment options. Case A 35-year-old woman presented with an aggressive ACTH-secreting pituitary adenoma that initially responded to concurrent temozolomide and capecitabine prior to metastasizing to the liver. Following treatment with ipilimumab and nivolumab, the tumor volume of the dominant liver metastasis reduced by 92%, and the recurrent intracranial disease regressed by 59%. Simultaneously, her plasma ACTH level decreased from 45,550 pg/mL to 66 pg/mL. Molecular Evaluation Both prospective clinical sequencing with Memorial Sloan Kettering–Integrated Mutation Profiling of Actionable Cancer Targets and retrospective whole-exome sequencing were performed to characterize the molecular alterations in the chemotherapy-naive pituitary adenoma and the temozolomide-resistant liver metastasis. The liver metastasis harbored a somatic mutational burden consistent with alkylator-induced hypermutation that was absent from the treatment-naive tumor. Resistance to temozolomide treatment, acquisition of new oncogenic drivers, and subsequent sensitivity to immunotherapy may be attributed to hypermutation. Conclusion Combination treatment with ipilimumab and nivolumab may be an effective treatment in pituitary carcinoma. Clinical sequencing of pituitary tumors that have relapsed following treatment with conventional chemotherapy may identify the development of therapy-induced somatic hypermutation, which may be associated with treatment response to immunotherapy.

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