Abstract
Background: Mutations of the genes encoding the α subunit of the stimulatory G protein (Gs) and of the inhibiting Gi2 protein (GNAS1 and GNAI2 genes, respectively) have been described in various endocrine neoplasias, including pituitary tumors. Aim: To search for mutations of GNAS1 and GNAI2 in a continuous series of nonfunctioning pituitary adenoma (NFPA) patients neurosurgically treated. Subjects and methods: The surgical samples of 22 patients who have been defined and characterized on a clinical, biochemical, histological, and immunohistochemical point of view have been processed for investigating the presence of the above mutations by PCR amplification of the hot spots exons 8 and 9 of GNAS1, and exons 5 and 6 of GNAI2, followed by direct sequencing. Moreover, the promoter region of GNAI2, in order to assess the prevalence of single nucleotide polymorphisms (SNP), was investigated in the same series. Results: A CGT>TGT mutation at codon 201 of GNAS1 gene in a single case of NFPA was found, but no mutation of GNAI2A was demonstrated. Conclusions: This finding suggests and confirms that G-protein mutations are rare and not crucial in NFPA development. Additionally, we found a silent SNP at codon 318 in the promoter of the Gi2α gene in one out of the 22 NFPA.
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R.M. Ruggeri and L Santarpia equally contributed to this work.
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Ruggeri, R.M., Santarpia, L., Curtò, L. et al. Non-functioning pituitary adenomas infrequently harbor G-protein gene mutations. J Endocrinol Invest 31, 946–949 (2008). https://doi.org/10.1007/BF03345630
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DOI: https://doi.org/10.1007/BF03345630