GH/PRL-secreting pituitary macroadenoma associated with GNAS p.Gln227Leu mutation: pediatric case report and review

Consensus guideline for the diagnosis and management of pituitary adenomas in childhood and adolescence: Part 1, general recommendations

Tumours of the anterior part of the pituitary gland represent just 1% of all childhood (aged <15 years) intracranial neoplasms, yet they can confer high morbidity and little evidence and guidance is in place for their management. Between 2014 and 2022, a multidisciplinary expert group systematically developed the first comprehensive clinical practice consensus guideline for children and young people under the age 19 years (hereafter referred to as CYP) presenting with a suspected pituitary adenoma to inform specialist care and improve health outcomes. Through robust literature searches and a Delphi consensus exercise with an international Delphi consensus panel of experts, the available scientific evidence and expert opinions were consolidated into 74 recommendations. Part 1 of this consensus guideline includes 17 pragmatic management recommendations related to clinical care, neuroimaging, visual assessment, histopathology, genetics, pituitary surgery and radiotherapy. While in many aspects the care for CYP is similar to that of adults, key differences exist, particularly in aetiology and presentation. CYP with suspected pituitary adenomas require careful clinical examination, appropriate hormonal work-up, dedicated pituitary imaging and visual assessment. Consideration should be given to the potential for syndromic disease and genetic assessment. Multidisciplinary discussion at both the local and national levels can be key for management. Surgery should be performed in specialist centres. The collection of outcome data on novel modalities of medical treatment, surgical intervention and radiotherapy is essential for optimal future treatment.

Genetic and Epigenetic Pathogenesis of Acromegaly

Simple Summary

Various genetic and epigenetic factors are involved in the pathogenesis of somatotroph tumors. Although GNAS mutations are the most prevalent cause of somatotroph tumors, the cause of half of all pathogenesis occurrences remains unclarified. However, recent findings including the pangenomic analysis, such as genome, transcriptome, and methylome approaches, and histological characteristics of pituitary tumors, the involvement of AIP and GPR101, the mechanisms of genomic instability, and possible involvement of miRNAs have gradually unveiled the whole landscape of underlying mechanisms of somatotroph tumors. In this review, we will focus on the recent advances in the pathogenesis of somatotroph tumors.

Abstract

Acromegaly is caused by excessive secretion of GH and IGF-I mostly from somatotroph tumors. Various genetic and epigenetic factors are involved in the pathogenesis of somatotroph tumors. While somatic mutations of GNAS are the most prevalent cause of somatotroph tumors, germline mutations in various genes (AIP, PRKAR1A, GPR101, GNAS, MEN1, CDKN1B, SDHx, MAX) are also known as the cause of somatotroph tumors. Moreover, recent findings based on multiple perspectives of the pangenomic approach including genome, transcriptome, and methylome analyses, histological characterization, genomic instability, and possible involvement of miRNAs have gradually unveiled the whole landscape of the underlying mechanisms of somatotroph tumors. In this review, we will focus on the recent advances in genetic and epigenetic pathogenesis of somatotroph tumors.

MicroRNA‑29‑3p regulates the β‑catenin pathway by targeting IGF1 to inhibit the proliferation of prolactinoma cells

The present study aimed to analyze the effects and underlying mechanisms of microRNA (miR)-29-3p on the proliferation and secretory abilities of prolactinoma cells by targeting insulin-like growth factor (IGF)-1/β-catenin. The relationship between miR-29a-3p and the survival of prolactinoma cells was analyzed with the Kaplan-Meier method in reference to The Cancer Genome Atlas. The expression levels of miR-29a-3p and IGF-1 in MMQ and GH3 cells were detected. A dual-luciferase reporter gene assay was performed to verify the combination of miR-29a-3p and IGF-1. Cells were transfected with a miR-29a-3p mimic and/or IGF-1 pcDNA3.1 to analyze the effects on the proliferation, apoptosis and secretion of prolactin (PRL) and growth hormone (GH) of prolactinoma cells. The effects on β-catenin in the cytoplasm and nucleus were investigated by western blot analysis. The results showed that miR-29a-3p expression was low in MMQ and GH3 cells. Overexpression miR-29a-3p inhibited IGF-1 mRNA and protein expression. miR-29a-3p inhibited cell proliferation and PRL and GH expression, and promoted apoptosis by inhibiting IGF-1. Increasing the expression of miR-29a-3p increased β-catenin levels in the cytoplasm, whereas IGF-1 promoted β-catenin activation and entry into the nucleus, and reversed the inhibitory effects of miR-29a-3p on β-catenin. To conclude, miR-29a-3p inhibited the proliferation and secretory abilities of prolactinoma cells by inhibiting nuclear translocation of β-catenin via a molecular mechanism that is inseparable from IGF-1.

Pediatric pituitary adenoma with mixed FSH and TSH immunostaining and FSH hypersecretion in a 6 year-old girl with precocious puberty: case report and multidisciplinary management

OBJECTIVE

We describe a rare case of functioning gonadotropins-producing pediatric adenoma immunostaining positively for FSH and focally for TSH causing central precocious puberty associated to central hypothyroidism in a 6 year-old girl.

MATERIALS AND METHODS

Clinical evaluation revealed precocious puberty, as confirmed by hormonal determination with elevated FSH and estradiol, while central hypothyroidism was biochemically diagnosed by a low fT4 and normal TSH. Head MRI showed the presence of a hyperintense pituitary lesion. The patient successfully underwent transsphenoidal endoscopic resection of the pituitary macroadenoma.

RESULTS

Pathologic evaluation of the tissue resected at surgery confirmed the diagnosis of pituitary adenoma with positive immunohistochemistry for FSH and focally for TSH in a mixed pattern. Ten months after surgery, there were no neurological signs and symptoms. Postoperative head MRI showed no abnormalities and no evidence of tumor regrowth.

CONCLUSIONS

Early and accurate diagnosis, multidisciplinary approach and close follow up are crucial factors for the favorable outcome.