Male gonadotroph adenoma: report of three cases and a review of the literature.

We herein report three cases of gonadotroph adenoma in men (36-72 years of age) presenting with visual impairment and suprasellar masses measuring approximately 20 to 30 mm in diameter. Endocrinological examinations were normal, except for slightly increased follicle stimulating hormone (FSH) levels in two cases. Based on the tentative diagnosis of non-functioning pituitary adenoma, transsphenoidal surgery was performed, which revealed that the tumors consisted of FSH- and LH-positive cells.

Correlation between histological subtypes and MRI findings in clinically nonfunctioning pituitary adenomas.

Clinically nonfunctioning pituitary adenomas (CNFPAs) consist of several histological subtypes, including null cell adenoma (NCA), silent gonadotroph cell adenoma (SGA), silent corticotroph adenoma (SCA), and other silent adenomas (OSA) (i.e., GH, TSH, and prolactin adenomas).

Differential expression of genes related to drug responsiveness between sparsely and densely granulated somatotroph adenomas.

There are two main subtypes of GH-producing pituitary adenoma: densely granulated (DG-type) and sparsely granulated (SG-type). Despite the difference in drug responsiveness between the two subtypes, their molecular mechanisms remain unknown. The aim of this study is to evaluate the differential expression of genes related to drug responsiveness between the two subtypes of somatotroph adenoma, and their relationship to the clinical characteristics.

Krüppel-like zinc-finger transcription factor 5 (KLF5) is highly expressed in large and giant unruptured cerebral aneurysms.

Background: Krüppel-like zinc-finger transcription factor 5 (KLF5), known as BTEB2 and IKLF, has several biological functions that involve cell proliferation, development, and apoptosis. In human cerebral aneurysms, macrophage infiltration is profoundly associated with growth and rupture, but the role of KLF5 remains unclear. We examined the significance of KLF5 expression in cerebral aneurysms.

A silent follicle-stimulating hormone-producing pituitary adenoma in a teenage male.

An 18-year-old male was referred to Toranomon Hospital seeking reoperation for recurrent clinically nonfunctioning pituitary adenoma. A pituitary macroadenoma was first suspected at age 15 due to intractable headaches. Endocrine data were unremarkable except slightly elevated serum follicle-stimulating hormone (FSH).

Analysis of expression and structure of the rat GH-secretagogue/ghrelin receptor (Ghsr) gene: roles of epigenetic modifications in transcriptional regulation.

In the current study, to elucidate the molecular basis of cell type-specific expression of the GH-secretagogue/ghrelin receptor type 1A (GHSR1A), we characterized the structure and putative promoter region of the rat Ghsr gene. We identified an alternative 5'-untranslated first exon that contains multiple transcription start sites, and confirmed a 200-bp sequence proximal to this exon to be sufficient for basal promoter activity. A promoter-associated CpG island conserved across different species was found to be hypomethylated in Ghsr1a-expressing cell lines, while being heavily methylated in non-expressing cells.

A case of corticotroph carcinoma that caused multiple cranial nerve palsies, destructive petrosal bone invasion, and liver metastasis.

A 52-year-old woman experienced sudden onset of double vision due to a right abducens nerve palsy and was diagnosed as having a pituitary macroadenoma that invaded into the right cavernous sinus. Otherwise, she was asymptomatic despite marked elevation of ACTH (293 pg/ml) and cortisol (24.6 μg/dl) levels.

Adult combined GH, prolactin, and TSH deficiency associated with circulating PIT-1 antibody in humans.

The pituitary-specific transcriptional factor-1 (PIT-1, also known as POU1F1), is an essential factor for multiple hormone-secreting cell types. A genetic defect in the PIT-1 gene results in congenital growth hormone (GH), prolactin (PRL), and thyroid-stimulating hormone (TSH) deficiency. Here, we investigated 3 cases of adult-onset combined GH, PRL, and TSH deficiencies and found that the endocrinological phenotype in each was linked to autoimmunity directed against the PIT-1 protein.

Increased expression of HMGA1 correlates with tumour invasiveness and proliferation in human pituitary adenomas.

Aims: High-mobility group A1 (HMGA1) is highly expressed in various benign and malignant tumours. The development of pituitary adenoma in Hmga1 transgenic mice has been reported. However, no studies have investigated HMGA1 expression and its clinical significance in human pituitary adenomas.

DNA methyltransferases 1, 3a, and 3b overexpression and clinical significance in gastroenteropancreatic neuroendocrine tumors.

The alteration of DNA methylation is one of the most common epigenetic changes in human cancers. Three genes, namely, DNA methyltransferase 1, 3a, and 3b, which code for DNA methyltransferases that affect promoter methylation status, are thought to play an important role in the development of cancers and may be good anticancer therapy targets. The methylation of tumor suppressor genes has been reported in gastroenteropancreatic neuroendocrine tumors; however, there have been no studies about DNA methyltransferase protein expression and its clinical significance in gastroenteropancreatic neuroendocrine tumors.

[Successful rituximab monotherapy in a patient with mucosa-associated lymphoid tissue lymphoma of the rectum with trisomy 3, 18].

A 62-year-old man was referred to our hospital with enlargement of mucosa-associated lymphoid tissue (MALT) lymphoma of the rectum after the eradication of Helicobacter pylori. The patient was given a diagnosis of stage I MALT. Endoscopic observation revealed an enlarged rectal tumor with 3, 18 double trisomy.

Pituitary adenomas that show a faint GH-immunoreactivity but lack fibrous body: Pit-1 adenoma with endocrinologically low activity.

Growth hormone (GH)-producing pituitary adenomas have been classified into densely and sparsely granulated adenomas. The latter are chromophobic with weak GH-positivity and characteristically possess fibrous body (FB), aggregation of cytokeratin filaments. We report eight cases of unusual chromophobic adenomas.

Pituitary and stalk lesions (infundibulo-hypophysitis) associated with immunoglobulin G4-related systemic disease: an emerging clinical entity.

Inflammatory lesions of the pituitary gland are rarely encountered. Recently, the concept of immunoglobulin G4 (IgG4)-related systemic disease was proposed in Japan, and more than 20 cases have been reported as possibly associated with infundibulo-hypophysitis since 2000. We herein review such case reports in the published literature and in the abstracts of scientific meetings.

Clinicopathological characterization of TSH-producing adenomas: special reference to TSH-immunoreactive but clinically non-functioning adenomas.

Thyrotropin (thyroid-stimulating hormone (TSH))-producing pituitary adenomas have been known to be quite variable in clinical features covering from typical functioning TSH-producing adenomas (FTSHomas) associated with hyperthyroidism to clinically silent TSH cell adenomas (STAs) that are apparently unassociated with hyperthyroidism. It is important to distinguish STAs from other types of clinically non-functioning adenomas for adequate postoperative managements. However, because of rareness of TSH-producing adenomas, their histopathological features linking to the clinical manifestations have not been well characterized.

High incidence of low O(6)-methylguanine DNA methyltransferase expression in invasive macroadenomas of Cushing's disease.

Context: Crooke's cell adenoma (CCA), characterized by massive Crooke's hyaline change in corticotroph adenoma, causes a rare subtype of Cushing's disease. In contrast to ordinary corticotroph adenomas, CCAs are generally aggressive and present as invasive macroadenomas, which are refractory to both surgery and radiotherapy and have a high-recurrence rate. Moreover, some patients with CCA present with distant or craniospinal metastases.

Expression of p18(INK4C) is down-regulated in human pituitary adenomas.

Cyclin-dependent kinase inhibitors represented by the INK4 family comprising p16(INK4A), p15(INK4B), p18(INK4C), and p19(INK4D) are regulators of the cell cycle shown to be aberrant in many types of cancer. Mice lacking p18(Ink4c) exhibit a series of phenotypes including the development of widespread organomegaly and pituitary adenomas. The objective of our study is to examine the role of p18(INK4C) in the pathogenesis of human pituitary tumors.

Overexpression of HMGA2 relates to reduction of the let-7 and its relationship to clinicopathological features in pituitary adenomas.

High-mobility group A2 is highly expressed during embryogenesis and in various benign and malignant tumors. Recent studies report that high-mobility group A2 is negatively regulated by the let-7 microRNAs (miRNAs) family in vitro. The development of pituitary adenomas in high-mobility group A2 transgenic mice showed that high-mobility group A2 may be involved in pituitary tumorigenesis.

Altered fracture callus formation in chondromodulin-I deficient mice.

Chondromodulin-I (Chm-I) is a glycoprotein that stimulates the growth of chondrocytes and inhibits angiogenesis in vitro. Mice lacking the Chm1 gene show abnormal bone metabolism and pathological angiogenesis in cardiac valves in the mature stage although they develop normally without aberrations in endochondral bone formation during embryogenesis or in cartilage development during growth. These findings indicate that Chm-I is critical under conditions of stress such as bone repair through endochondral ossification of a fracture callus.