FRA-1 protein overexpression is a feature of hyperplastic and neoplastic breast disorders.

BACKGROUND: Fos-related antigen 1 (FRA-1) is an immediate early gene encoding a member of AP-1 family of transcription factors involved in cell proliferation, differentiation, apoptosis, and other biological processes. fra-1 gene overexpression has an important role in the process of cellular transformation, and our previous studies suggest FRA-1 protein detection as a useful tool for the diagnosis of thyroid neoplasias. Here we investigate the expression of the FRA-1 protein in benign and malignant breast tissues by immunohistochemistry, Western blot, RT-PCR and qPCR analysis, to evaluate its possible help in the diagnosis and prognosis of breast neoplastic diseases. METHODS: We investigate the expression of the FRA-1 protein in 70 breast carcinomas and 30 benign breast diseases by immunohistochemistry, Western blot, RT-PCR and qPCR analysis. RESULTS: FRA-1 protein was present in all of the carcinoma samples with an intense staining in the nucleus. Positive staining was also found in most of fibroadenomas, but in this case the staining was present both in the nucleus and cytoplasm, and the number of positive cells was lower than in carcinomas. Similar results were obtained from the analysis of breast hyperplasias, with no differences in FRA-1 expression level between typical and atypical breast lesions; however the FRA-1 protein localization is mainly nuclear in the atypical hyperplasias. In situ breast carcinomas showed a pattern of FRA-1 protein expression very similar to that observed in atypical hyperplasias. Conversely, no FRA-1 protein was detectable in 6 normal breast tissue samples used as controls. RT-PCR and qPCR analysis confirmed these results. Similar results were obtained analysing FRA-1 expression in fine needle aspiration biopsy (FNAB) samples. CONCLUSION: The data shown here suggest that FRA-1 expression, including its intracellular localization, may be considered a useful marker for hyperplastic and neoplastic proliferative breast disorders.

Familial combined pituitary hormone deficiency due to a novel mutation R99Q in the hot spot region of Prophet of Pit-1 presenting as constitutional growth delay.

Combined pituitary hormone deficiency (CPHD) is characterized by impaired production of GH and one or more of the other anterior pituitary hormones. Prophet of Pit-1 (PROP-1), one of the pituitary specific homeodomain transcription factors, is involved in the differentiation of the anterior pituitary cells (somatotrophs, lactotrophs, thyrotrophs, and gonadotrophs), and PROP-1 gene mutations may interfere with the development of these cells, resulting in CPHD. We performed molecular analyses of the PROP-1 gene in two siblings, born to consanguineous parents, who presented with short stature. The index patient, a boy, was initially diagnosed with constitutional growth delay based on familial short stature, low parental target height, normal GH secretion, and imaging of the pituitary gland. On follow-up, auxological data and pubertal delay prompted a thorough reevaluation, which documented GH, TSH, and gonadotropin deficiencies. Direct sequencing of the PROP-1 gene revealed a novel homozygous transition 296G-->A in exon 2 in the two affected siblings. The mutation substitutes a highly conserved arginine by a glutamine at codon 99 (R99Q) in the second helix of the DNA-binding domain of the PROP-1 protein. Compared with wild-type PROP-1, R99Q displays a significant decrease in DNA binding on a paired box response element (PRDQ9) and trans-activation of a luciferase reporter gene. The findings emphasize the importance of repeated evaluations and illustrate that patients with CPHD associated with PROP-1 mutations present with a phenotypic spectrum, suggesting that the consequences of distinct PROP-1 mutations may be diverse and/or that additional factors, such as modifier genes, may have an impact on their expressivity.

A mutation in the KCNE3 potassium channel gene is associated with susceptibility to thyrotoxic hypokalemic periodic paralysis.

Hypokalemic Periodic Paralyses comprise diverse diseases characterized by acute and reversible attacks of severe muscle weakness, associated with low serum potassium. The most common causes are Familial Hypokalemic Periodic Paralysis (FHypoKPP), an autosomal dominant disease, and Thyrotoxic Hypokalemic Periodic Paralysis (THypoKPP), secondary to thyrotoxicosis. Symptoms of paralysis are similar in both diseases, distinguished by thyrotoxicosis present in THypoKPP. FHypoKPP is caused by mutations in ionic channel genes calcium (CACN1AS), sodium (SCN4A) and potassium (KCNE3). Since both diseases are similar, we tested the hypothesis that THypoKPP could carry the same mutations described in FHypoKPP, being the paralysis a genetically conditioned complication of thyrotoxicosis. In 15 patients with THypoKPP, using target-exon PCR, CSGE screening, and direct sequencing, we excluded known mutations in CACN1AS and SCN4A genes. On the other hand, we were able to identify the R83H mutation in the KCNE3 gene in one sporadic case of THypoKPP, a man who had been asymptomatic until developing thyrotoxicosis caused by Graves' disease; we confirmed the disease-causing mutation in 2 of 3 descendants. R83H was recently found in two FHypoKPP unrelated families, in which the mutant decreased outward potassium flux, resulting in a more positive resting membrane potential. We, therefore, identified the first genetic defect in THypoKPP, a mutation in the KCNE3 gene.