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The somatostatin analog octreotide has proven to be an effective form of treatment for various hypersecretory states including acromegaly. This report describes the effects of escalating doses of octreotide on the growth hormone (GH) profiles, insulin-like growth factor-1 (IGF-1), prolactin (PRL), and adverse effects in 99 patients with acromegaly. Treatment with octreotide was initiated at 50 μg sc every 8 h and the dose gradually titrated to a maximum of 1500 μg/d if more than 75% of GH determinations in a 12-h day profile were above detection limits. This dose was maintained for the duration of 6 months. Seventy-three percent of patients did not reach the GH reduction criterion at the 300 μg dose. Mean GH levels decreased from 33±4 μg/l to 10±1 μg/l (p

Basic fibroblast growth factor (bFGF) is a potent mitogenic and angiogenic factor that is known to regulate GH, PRL, and TSH secretion. Sequences within a bFGF gene family member have been detected in transforming DNA samples derived from human PRL-secreting tumors. Furthermore, elevated serum concentrations of bFGF have been noted in patients with multiple endocrine neoplasia-1. To further examine the significance of bFGF in sporadic human pituitary adenomas, we investigated the expression of bFGF by these tumors. Using an enzyme-linked immunoassay that recognizes all 16-24 kilodalton molecular mass forms of bFGF, we measured circulating serum concentrations in 21 patients with sporadic pituitary adenomas; they ranged from less than 0.5-84 pg/mL and declined following surgical adenomectomy. To confirm the pituitary source of this growth factor, we determined in vitro bFGF release from 43 adenomas (10 GH, 7 PRL, 10 ACTH, 14 gonadotrope adenomas/oncocytomas, and 2 silent subtype 3 adenomas). bFGF was present with wide variability (0.75-2100 pg/24 h.10(5) cells) in conditioned culture media of all adenomas examined. The adenohypophysial source of this growth factor was further demonstrated by the reverse hemolytic plaque assay. Variable bFGF messenger RNA expression was identified by the reverse-transcription polymerase chain reaction technique in 9 functional (2 PRL, 5 GH, 2 ACTH) and 7 nonfunctional (1 oncocytoma, 2 null cell, 2 gonadotrope, 2 Silent Subtype 3) adenomas examined. bFGF levels were unaltered in vitro following hypothalamic hormone stimulation/inhibition. The lack of a bFGF signal peptide sequence and hypothalamic hormone-independence suggest that secretion of this factor may be independent of pituitary hormone regulation. Immunocytochemistry failed to localize bFGF in tumors that released this factor in vitro, suggesting that storage of this peptide does not correlate with its synthesis and release. In conclusion, the heterogenous expression of bFGF suggests that it may play a specific and selective role in the tumorigenic process of some pituitary adenomas.

Growth factors induce cell proliferation and are implicated in the multistep process of tumorigenesis. Transforming growth factor-alpha (TGF alpha), a peptide that binds to the epidermal growth factor receptor, is expressed by carcinomas and normal tissues. To investigate the possible role of TGF alpha in adenohypophysial tumorigenesis, we studied its expression in nontumorous human pituitary and different clinically and morphologically characterized human pituitary adenomas. Ribonucleic acid was reverse transcribed and amplified by polymerase chain reaction; transcript signals were identified with marked variation in 14 of 15 adenomas, and a weak signal was detected in nontumorous pituitary. Immunohistochemical positivity was found with variable intensity in all adenoma types, but not all tumors. Ultrastructural immunogold localized TGF alpha in endoplasmic reticulum, in Golgi apparatus, and on cell membranes; surface localization was confirmed by immunofluorescence. To assess possible secretion, the reverse hemolytic plaque assay was performed; small plaques were identified using an antibody that recognizes the extracellular domain of pro-TGF alpha; however, the plaques did not increase in size with time, suggesting that they detected membrane-anchored TGF alpha. Moreover, TGF alpha was undetectable by enzyme-linked immunosorbent assay in pituitary tumor-conditioned culture media. The marked variable expression of TGF alpha, the absence of secretion in measurable quantities, and the preferential membrane localization suggest a specific juxtacrine mechanism for TGF alpha in pituitary tumorigenesis.

SummaryObjective To evaluate demographic data and quality of care of patients with acromegaly in Canada and their evolution over time and secondly, to evaluate predictors of co-morbidities and treatment outcomes. Design and patients Retrospective analyses of clinical, biochemical and treatment outcome data of 649 patients with acromegaly (males: 50·7%) followed from 1980 to 2010 (mean 10·2 years, SD 13·7) in eight tertiary care centres from six Canadian provinces. Results In comparison to 1980–1994, the number of patients referred with acromegaly in the last 15 years was higher with female preponderance (52·8% vs 41·4%, P = 0·01) and an older age at diagnosis (46·4 ± 14 vs 41·3 ± 12 years, P

The brain is an exceedingly rare site of metastasis in medullary thyroid carcinoma (MTC). A 50-year-old female who had a history of micro-MTC 11 years prior developed a cerebellar metastasis which was incidentally discovered. Imaging revealed a right cerebellar hemispheric mass with contrast enhancement on CT scans. Histopathologic exam demonstrated a metastatic tumour composed of nodules and sheets of large tumour cells with abundant cytoplasm. Immunohistochemistry confirmed the origin from a MTC. This case report highlights the unique features of an unusual metastatic brain tumour, which followed an indolent course for a long time despite multiple distant metastases.

C-terminal binding protein (CtBP) is a transcriptional corepressor that plays an important role in mammalian development and tumorigenesis. We demonstrate that CtBP is expressed in adenohypophyseal cells and is expressed at high levels in human corticotroph, somatotroph, and lactotroph pituitary adenomas. CtBP interacts with Ikaros isoforms in GH4 and AtT20 pituitary tumor cells. Ikaros and CtBP1 expression is coordinately induced by hypoxia, and this response is abrogated by CtBP1 deficiency. Forced reduction of CtBP1 leads to reduced cell growth, up-regulation of Sprouty 2, and down-regulation of ectonucleotide pyrophosphatase phosphodiesterase 2 (Enpp2). Consistent with diminished Enpp2 activity, CtBP1-deficient pituitary cells are more susceptible to hypoxia-induced apoptosis, which is rescued by Enpp2-derived lysophosphatidic acid treatment. These results identify putative oncogenic properties of CtBP1 and provide new insights into the overlapping functions of two members of the chromatin remodeling network in the response to hypoxic pituitary tumor cell drive.

This prospective study defines the clinical and biochemical features of acromegaly in a large cohort of patients. There was no difference in sex distribution, and for men and women the mean ages at diagnosis (40 +/- 12 and 40 +/- 14 yr, respectively) were similar. Nearly three-quarters of patients were overweight and some 12% severely overweight; the frequency and severity of obesity also was not different between the sexes. Half of patients were hypertensive or were taking anti-hypertensive drugs. Neither GH nor insulin levels were significantly different between normotensive and hypertensive patients. Acral growth and facial coarsening, soft tissue swelling, and excessive perspiration were present in the majority (98%) of patients. Mean serum GH, Sm-C, and PRL levels did not differ between the sexes. Sm-C levels correlated with mean GH concentration (r = 0.31, p < 0.001), both variables inversely related to age. With each decade of life, mean GH and Sm-C levels declined by 7.6 +/- 0.2 ng/mL and 0.5 +/- 0.2 U/mL, respectively. Impaired glucose tolerance was diagnosed in 36% and frank diabetes mellitus in 30% of patients. Hyperprolactinemia was noted in 18% of patients. Galactorrhea was noted in 43 (9%) patients, most of whom were female; the mean GH levels of patients with galactorrhea (60.1 +/- 13 ng/mL) were higher than those of patients without (35.4 +/- 2.6 ng/mL, p = 0.02). Acromegaly appears to afflict men and women equally with a preponderance of presentation in the fourth decade of life.(ABSTRACT TRUNCATED AT 250 WORDS)

The SRIH analog octreotide is a potent GH-inhibiting agent that has been used to effectively treat patients with acromegaly. To investigate the morphological changes induced by octreotide on GH-producing pituitary tumors, we examined 86 adenomas from acromegalic patients who participated in a multicenter study. GH- producing pituitary adenomas removed from 43 patients treated preoperatively with octreotide for 4 months were compared to those obtained from 43 untreated acromegalic patients. Tissue samples were studied by histology, immunohistochemistry, and transmission electron microscopy as well as light microscopic and ultrastructural morphometry. The morphological appearance of some tumors was unaltered by octreotide treatment. Necrotic changes were not apparent in any. Acidophilia and GH immunoreactivity were more pronounced in the octreotide-treated tumors. Perivascular and interstitial fibrosis was more prevalent in the octreotide group (72% vs. 42%). An increase in hormone granularity was obvious in 4 of 15 densely granulated and 2 of 9 sparsely granulated (SG) tumors from treated patients. A decrease in cell size was conspicuous in 4 of 15 densely granulated and 2 of 10 SG adenomas. There was a slight downward trend in the cell and cytoplasmic size in all treated tumors and a slight upward trend in secretory granule size in treated SG adenomas. Only 2 of 9 SG adenomas in the octreotide group, however, demonstrated a statistically significant reduction in cell and cytoplasmic size. There was no statistically significant change in the size of nuclei, secretory granules, or lysosomes between the 2 groups. Decreased cell size and increased granularity were not linked, however. We conclude that there are no striking morphological alterations in GH pituitary adenomas that can be consistently associated with octreotide treatment.

Koop BL, Harris AG. Ezzat S. Effect of octreotide on glucose tolerance in acromegaly. Eur J Endocrinol 1994;130:581–6. ISSN 0804–4643 To determine the effect of the somatostatin analog octreotide on glucose tolerance in acromegaly, we examined glucose profiles, oral glucose tolerance and the insulinogenic index in patients treated with this analog. Ninety patients participated in a long-term, prospective, open-label study. There was no significant change between mean daily blood glucose profiles at baseline or during octreotide treatment. Using glucose tolerance test criteria, 61% of 90 patients had normal baseline glucose tolerance. While on octreotide, 20% and 29% of these patients, respectively, developed impaired glucose tolerance or became frankly diabetic. Conversely, three of the patients who were diabetic at baseline (N = 11) became normal (18%) or developed impaired glucose tolerance (9%) during octreotide therapy. There was no relationship between the dose of octreotide and change in glycemic state. The insulinogenic index (insulin/glucose) response to a glucose challenge decreased uniformly in octreotide-treated patients. Female patients and those with elevated baseline insulin levels were more likely to develop diabetes mellitus during octreotide therapy. In conclusion, octreotide significantly alters glucose tolerance in patients with acromegaly, mandating glucose monitoring during this form of therapy. Alan G Harris, Division of Clinical Pharmacology, Department of Medicine, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA

NMR spectroscopy is a useful tool for monitoring multiple intermediate metabolic pathways in different organs in intact animals and humans. We report the effect of the somatostatin analogue octreotide on the fate of 13C-labeled glucose administered to fasted and well-fed rats as determined by NMR spectroscopy. The production of 13C-labeled glycogen and its subsequent breakdown after the end of infusion was identified with a time resolution of 7 min. Hepatic glycogen synthesis was not different between control and octreotide-treated animals but persisted for 15 min after the end of the infusion only in control animals. Glycogenolysis, however, was initiated immediately after the end of infusion in octreotide-treated animals where the half-life of glycogen was 40 min compared with 68 min in control animals. However, once initiated, the rate of glycogenolysis was not significantly altered by octreotide. Although octreotide had no effect on glucose signal intensities in fasted animals, 13C glucose signals were more intense in octreotide compared with control well-fed animals. In conclusion, octreotide alters rat hepatic metabolism by accelerating the onset of glycogenolysis and stimulating glucose accumulation without significantly interfering with glycogen synthesis.

Pituitary tumors are common intracranial neoplasms, yet few germline abnormalities have been implicated in their pathogenesis. Here we show that a single nucleotide germline polymorphism (SNP) substituting an arginine (R) for glycine (G) in the FGFR4 transmembrane domain can alter pituitary cell growth and hormone production. Compared with FGFR4-G388 mammosomatotroph cells that support prolactin (PRL) production, FGFR4-R388 cells express predominantly growth hormone (GH). Growth promoting effects of FGFR4-R388 as evidenced by enhanced colony formation was ascribed to Src activation and mitochondrial serine phosphorylation of STAT3 (pS-STAT3). In contrast, diminished pY-STAT3 mediated by FGFR4-R388 relieved GH inhibition leading to hormone excess. Using a knock-in mouse model, we demonstrate the ability of FGFR4-R385 to promote GH pituitary tumorigenesis. In patients with acromegaly, pituitary tumor size correlated with hormone excess in the presence of the FGFR4-R388 but not the FGFR4-G388 allele. Our findings establish a new role for the FGFR4-G388R polymorphism in pituitary oncogenesis, providing a rationale for targeting Src and STAT3 in the personalized treatment of associated disorders., Author Summary Several human cancers have been associated with increased growth hormone levels. Here we show that a frequent single nucleotide polymorphism (SNP) associated with increased cancer risk and progression also deregulates pituitary function. Through recruitment of a distinct STAT3 signaling cascade, this polymorphic receptor variant drives pituitary growth hormone cell survival and hormonal output. These findings provide an example of a potentially common genetic program shared between cancer and a hormone that promotes its progression.

Carney complex is a genetically heterogenous multiple neoplasia syndrome. Adrenal cortical carcinoma is a rare malignancy with a poor prognosis that is not recognized to be associated with this syndrome.We report a 22-yr-old female presenting with Carney complex who developed adrenal carcinoma. The response to adjunctive therapy is also described.We performed a detailed pathology review of the adrenal tumor to examine morphologic changes, Ki-67 labeling, and p53 expression. We also performed genetic testing of candidate genes and describe the response to radiation and kinase inhibition therapy.The patient presented with an 8.5-cm adrenal mass with a MIB-1 labeling index of 20% and unequivocal angioinvasion classified as a T3NXM0 carcinoma. The nontumorous adrenal cortex revealed characteristic features of primary pigmented nodular adrenocortical disease. Genetic analysis revealed a novel PRKAR1 frame shift mutation resulting in a premature stop codon and a heterozygous p53 polymorphic substitution previously noted in other solid carcinomas. Disease recurrence in the liver showed partial response to combined stereotactic radiotherapy and sorafenib multikinase inhibition.This represents an initial characterization of a malignancy among patients with Carney complex. Our findings have implications for disease surveillance and management of individuals with this genetic syndrome.

Background and Objective: Patients with early stage papillary thyroid cancer (PTC) who have had a thyroidectomy are often faced with the decision to accept or reject adjuvant radioactive iodine (RAI) treatment (remnant ablation). We have designed a patient-directed computerized decision aid, intended to educate patients about this choice as a contribution to the development of person-centered medicine. The objective of this study was to test the usability of this decision aid in patients with a recent diagnosis of early stage PTC, using a mixed methods approach. Methods: The decision aid was tested by individuals with early stage PTC (4 cm or smaller primary tumor with no known lymph node nor distant metastases), who had recently undergone thyroidectomy. After using the decision aid, the participants were interviewed, using semi-structured questions. Qualitative participant feedback was obtained, major themes were categorized and quantified. Results: The decision aid was tested by 50 participants; all 97 comments on the usability and all 67 comments on the credibility of the decision aid, were positive. There were 37 positive comments on the understandability of the decision aid, 8 neutral ones and no negative ones. Participants’ opinions on the relevance of the medical content were categorized as follows: 52 positive, 2 neutral and 1 negative. Furthermore, general comments about the decision aid were categorized as follows: 75 positive, 11 neutral and 8 negative. Conclusions: A patient-directed computerized decision aid explaining the choice of radioactive iodine remnant ablation compared to no remnant ablation, was received with largely positive feedback from individuals with a recent diagnosis of PTC. We advance our study as an important contribution to person-centered medicine for the patient with thyroid malignancy.

Acromegaly results from increased growth hormone and its target insulin-like growth factor-1, most commonly due to a pituitary tumour. As it is frequently accompanied by infertility, little is known about the course of this disease in pregnancy.We describe 13 new pregnancies in acromegalic women and compare their outcomes in a systematic review of the literature.We collected clinical, biochemical, imaging, and outcomes data during and following pregnancy and performed a systematic review for a total of 47 pregnancies. An extended analysis of 106 pregnancies was also performed.In 13 newly described cases, pregnancy was un-complicated without need for additional surgical intervention. In these pregnancies, adjunctive medical therapy was required in three patients. This was in the form of somatostatin analogs (SA) (3/13) as well as pegvisomant in 1/13 to control symptomatic and biochemical progression. One 37-year-old female succeeded in having two separate pregnancies 2 years apart both without need for any form of medical therapy. Review of an additional 34 published reports allowed for an analysis of outcomes in 47 pregnancies. Adjunctive medical therapy during pregnancy was required in 15 of these cases where 12 received SA and an additional three received dopamine agonists. None of these patients developed endocrine or neurologic complications during pregnancy. In an extended analysis of 106 pregnancies, treatment during pregnancy appears to be associated with good disease control but increased risk of microsomic or macrosomic newborns depending on the medical agent used.In 13 newly described pregnancies along with systematic review of an additional 34 cases indicate that pregnancy in treated acromegalic women can proceed without significant complications or teratogenicity. Medical treatment during pregnancy with DA or SA appears to be associated with altered neonatal weight. Nevertheless, gestation may have a beneficial impact on acromegaly control both during and following pregnancy.

In an effort to improve the diagnosis of pituitary tumors, we propose a synoptic approach to pituitary pathology reporting that will provide clear information to endocrinologists, neurosurgeons, neuropathologists, and surgical pathologists to advance the diagnosis and classification of pituitary adenomas.

Purpose: Well-differentiated thyroid cancer (WDTC) is the most frequent form of endocrine neoplasia. One of the main challenges in the management of this disease is distinguishing low-risk patients who can be treated by surgical resection of the lesion from those with a high likelihood of recurrence who need a more extensive approach, including total thyroidectomy and radioiodine ablation. Experimental Design: A tissue microarray (TMA) comprising 410 cases of WDTC was constructed with risk estimates for the following features: extrathyroidal extension, lymph node metastases, and vascular invasion. The variables examined were morphologic classification, candidate genetic, and proteomic biomarkers. Results: BRAF (Raf kinase type B) mutant carriers showed increased risk of developing invasion compared with wild-type (WT) cases. However, when classified morphologically, classic papillary thyroid carcinomas (PTC) showed much higher risk estimates for invasive features compared with follicular variant PTCs (FVPTC); within these morphologic subgroups, BRAF mutational status did not provide independent risk estimates. Staining intensities for membranous galectin-3 (Gal3), HBME-1, and CK19 and nuclear Gal3 were statistically validated as markers of aggressive behavior. Estrogen receptor beta (ERβ) was overexpressed in lesions with invasive behavior. The utility of these biomarkers remained statistically significant in the FVPTC. In contrast, a different set of biomarkers proved effective in classic PTC where upregulation of cyclin D1, loss of p27, and overexpression of ERβ were associated with invasive behavior. Conclusion: Different proteomic signatures validate the distinction of classic and FVPTC and provide a practical clinical mechanism to predict the thyroid cancer behavior and stratify patients for clinical management. Clin Cancer Res; 17(8); 2385–94. ©2011 AACR.

The effects of chronic GH and insulin-like growth factor-I (IGF-I) excess on bone metabolism were examined by measuring serum markers of bone formation and urine markers of bone resorption as well as vertebral bone densities in patients with active acromegaly. Fasting serum GH levels were elevated in all 27 patients (31 +/- 11 micrograms/L). Serum calcium levels were within the normal range, except in 3 of 27 (10%) patients with mild hypercalcemia. Urinary calcium excretion, however, was increased in 6 (22%) patients despite mainly normal serum PTH and 1,25-dihydroxyvitamin D levels, suggesting a direct renal GH and/or IGF-I-mediated calciuric effect. Urinary hydroxyproline/creatinine excretion was increased in all except 1 patient and correlated with plasma IGF-I levels (r = 0.49; P0.02; n = 22). A more specific indicator of bone collagen turnover, urinary type I collagen cross-linked N-telopeptide, was elevated in all except 1 patient and correlated with serum GH (r = 0.47; P0.02), IGF-I (r = 0.60; P0.005), and urinary hydroxyproline/creatinine excretion (r = 0.62; P0.001). Serum bone Gla protein (osteocalcin), a specific marker of osteoblastic activity, was also increased in 50% of the patients and correlated with urinary N-telopeptide (r = 0.47; P0.02), but not with serum GH or IGF-I concentrations. Trabecular bone density, as determined by quantitative computerized tomography of the lumbar spine, was increased in only 1 patient; 13 others had subnormal bone density. The results suggest that in long-standing acromegaly, osteoblastic and osteoclastic activities are increased. Vertebral trabecular bone mass is usually reduced. Urinary collagen cross-links may serve as a more specific marker of bone resorption in acromegaly.

Background. Acromegaly is usually the result of a pituitary growth hormone (GH)-cell adenoma or is more rarely due to ectopic secretion of GH-releasing hormone (GHRH). The authors previously described a more unusual form of acromegaly secondary to ectopic GH synthesis by a pancreatic islet cell tumor. Methods. One year after tumor resection and transient disease remission, multiple abdominal metastases were identified with accompanying elevated levels of circulating GH and insulin-like growth factor-1 (IGF-1). Serial 24-hour GH sampling was performed before and after intravenous GHRH or thyrotropin releasing hormone (TRH) administration during treatment with bromocriptine; treatment with the somatostatin (SRIF) analogue octreotide; or no treatment. RNA from abdominal tumor tissue was extracted and subjected to Northern gel electrophoresis and GH hybridization analysis. Results. Neither GHRH nor TRH resulted in stimulation of the elevated GH levels. Bromocriptine and octreotide did not suppress GH secretion but attenuated the thyroid stimulating hormone (TSH) response to TRH administration. Octreotide (as much as 1500 μg/d) was clinically, biochemically, and radiographically ineffective. GH-secreting abdominal tumor tissue expressed a 0.9-kb mRNA transcript consistent with the size of authentic human GH mRNA. Conclusion. The natural history and ectopic nature of a GH-producing pancreatic carcinoma has been documented, with biochemical remission occurring after initial tumor resection, with autonomous GH hypersecretion after tumor recurrence, and with RNA analysis demonstrating ectopic activation of GH gene transcription. Cancer 1993; 71:66-70.

Genome-wide association studies highlight the importance of the fibroblast growth factor (FGF) receptor as a risk factor for breast cancer development. In particular, FGFR4 has been implicated in membrane ruffling, cancer cell invasiveness, and clinical chemoresistance in breast cancer. In this work, we studied FGFR4 in both human breast cancers and cell lines. We examined primary human microdissected breast samples for FGFR4 mutations, polymorphisms, loss of heterozygosity (LOH), and DNA methylation status. We identified no activating somatic mutations of FGFR4; however, we did identify a high proportion of the FGFR4-R388 heterozygous germline polymorphism. Analysis of paired microdissected samples uncovered selective LOH at the FGFR4 locus in 50% of primary tumors. This LOH involved the FGFR4-WT allele as frequently as the cancer progression-associated FGFR4-G388R polymorphic allele. Further, we identified DNA methylation in one-third of cases that targeted the FGFR4-WT allele more often and occurred more frequently either in concert with or exclusively in lymph node metastases. The role of DNA methylation in silencing the FGFR4-WT allele was supported by azacytidine treatment findings and was also confirmed in mouse xenograft studies, demonstrating selective FGFR4-WT allelic methylation with corresponding gene down-regulation. These findings support a growth advantage function for FGFR4-R388 and underscore the complex role of DNA methylation and LOH in determining the penetrance of allelic selection in breast cancer progression. These findings therefore have critical therapeutic importance.

Activating mutations of GNAq protein in a hotspot at codon 209 have been recently described in uveal melanomas. Since these neoplasms share with thyroid carcinomas a high frequency of MAP kinase pathway-activating mutations, we hypothesized whether GNAq mutations could also play a role in the development of thyroid carcinomas. Additionally, activating mutations of another subtype of G protein (GNAS1) are frequently found in hyperfunctioning thyroid adenomas, making it plausible that GNAq-activating mutations could also be found in some of these nodules. To investigate thyroid papillary carcinomas and thyroid hyperfunctioning nodules for GNAq mutations in exon 5, codon 209, a total of 32 RET/PTC, BRAF, and RAS negative thyroid papillary carcinomas and 13 hyperfunctioning thyroid nodules were evaluated. No mutations were identified. Although plausible, GNAq mutations seem not to play an important role in the development of thyroid follicular neoplasms, either benign hyperfunctioning nodules or malignant papillary carcinomas. Our results are in accordance with the literature, in which no GNAq hotspot mutations were found in thyroid papillary carcinomas, as well as in an extensive panel of other tumors. The molecular basis for MAP-kinase pathway activation in RET-PTC/BRAF/RAS negative thyroid carcinomas remains to be determined.

Background Patients with early stage papillary thyroid carcinoma (PTC), are faced with the decision to either to accept or reject adjuvant radioactive iodine (RAI) treatment after thryroidectomy. This decision is often difficult because of conflicting reports of RAI treatment benefit and medical evidence uncertainty due to the lack of long-term randomized controlled trials. Methods We report the protocol for a parallel, 2-arm, randomized trial comparing an intervention group exposed to a computerized decision aid (DA) relative to a control group receiving usual care. The DA explains the options of adjuvant radioactive iodine or no adjuvant radioactive iodine, as well as associated potential benefits, risks, and follow-up implications. Potentially eligible adult PTC patient participants will include: English-speaking individuals who have had recent thyroidectomy, and whose primary tumor was 1 to 4 cm in diameter, with no known metastases to lymph nodes or distant sites, with no other worrisome features, and who have not received RAI treatment for thyroid cancer. We will measure the effect of the DA on the following patient outcomes: a) knowledge about PTC and RAI treatment, b) decisional conflict, c) decisional regret, d) client satisfaction with information received about RAI treatment, and e) the final decision to accept or reject adjuvant RAI treatment and rationale. Discussion This trial will provide evidence of feasibility and efficacy of the use of a computerized DA in explaining complex issues relating to decision making about adjuvant RAI treatment in early stage PTC. Trial registration Clinical Trials.gov Identifier: NCT01083550

Osteopontin (OPN) and its interacting partner CEA-cell adhesion molecule (CEACAM1) mediate similar biological functions and have been expressed in several types of cancer. Here we investigated the prognostic significance of OPN in thyroid tumours and correlated our findings with the expression of CEACAM1.297 human thyroid samples were collected in a tissue microarray and as fresh frozen samples to perform immunohistochemistry and western blotting for OPN and to compare these data with our previously published data on CEACAM1 expression.Nearly all normal samples were negative for OPN. Some thyroid adenomas were weakly OPN positive whereas many carcinomas were strongly positive. In contrast to CEACAM1, which was preferentially expressed in metastatic papillary carcinomas, no associations were found between OPN expression and patient age, gender and tumour size.These results may have future implications for the diagnosis and management of patients with thyroid cancers.

Serum insulin-like growth factor-1 (IGF-1) is a sensitive marker of growth hormone (GH) activity. The levels of IGF-1 vary widely, peaking during puberty and declining with advancing age. During adolescence, serum IGF-1 levels tend to correlate better with pubertal stage rather than chronological age. Here we discuss two cases of delayed puberty, both in their 20s, who presented with high serum IGF-1 but no clinical or biochemical evidence of hypersomatotropism as confirmed by appropriate GH response to an oral glucose challenge. Both individuals achieved full pubertal status with testosterone replacement therapy and their serum IGF-1 levels settled into normal age-specific range. We suggest that in chronologically adult individuals with delayed puberty, serum IGF-1 should not be interpreted on the basis of age-specific normal values but rather on their pubertal status. Furthermore, in the absence of another cause of elevated IGF-1, the expectation is that IGF-1 levels will decline towards age-normative ranges following androgen replacement therapy.

S OMATOSTATIN (SRIF) was discovered nearly two decades ago during the course of efforts to isolate growth hormone-releasing hormone (GHRH).’ Human pre-proSRIF is encoded by a single copy gene consisting of two exons separated by an 877-bp intronic sequence.2 This hypothalamic peptide was initially characterized as possessing a potent inhibitory effect on the secretion of pituitary growth hormone (GH).3 However, cloning, sequencing, and purification of the native prohormone (SRIF-28) and hormone (SRIF-14) has subsequently led to the discovery of the ubiquitous distribution and multifunctional properties of this peptide. However, the native SRIF hormones are rapidly degraded, with a half-life of less than 2 minutes in the circulation. Thus, to apply the physiologic activities of SRIF to clinical applications, it was necessary to develop longer-acting SRIF analogues. SMS 20 l-995, octreotide acetate (Sandostatin@), is an 8-amino acid cyclic derivative with a disulfide bond bridge that is relatively resistant to in vivo degradation. This analogue has an extended half-life of up to 1 I7 minutes in man4 and has been studied in multiple areas of clinical research and pharmacotherapy. This report will provide an overview of proven and potential endocrine applications of Sandostatin@, with particular emphasis on pituitary disorders, ectopic hormone production. diabetes mellitus, and endocrine manipulation of neoplastic conditions. Detailed results, risks, and benefits of these studies are fully described in subsequent reports.

Acromegaly is a unique condition characterized by chronic growth hormone (GH) and insulin-like growth factor-1 (IGF-1) hypersecretion usually due to a pituitary adenoma. Rarely, acromegaly can result from a GH-releasing hormone carcinoid or pancreatic neoplasm which stimulates the normal pituitary to secrete GH. This review describes the interactions between acromegaly and the gastrointestinal system. In contrast to the soft tissue and skeletal changes, clinical organomegaly of the liver, kidney, and spleen is unusual in patients with acromegaly and should warrant further investigations. The prevalence of cholelithiasis is notably increased by the use of the otherwise effective GH-lowering somatostatin analog, octreotide. Patients on long-term therapy with this agent may require anticholelithogenic treatment. The frequency of malignant and premalignant polyps of the colon justify the routine screening for these lesions in newly diagnosed patients with acromegaly.

Pituitary tumorigenesis infrequently involves intragenic mutations of oncogenes or tumor suppressor genes (Asa and Ezzat, 1998, 2002). Increasing evidence suggests that signals implicated in pituitary development may be relevant to neoplastic changes. Equally as important, accumulating evidence suggests that in contrast to other forms of solid neoplasia, pituitary tumors are frequently associated with epigenetic changes. In this review we discuss evolving models of epigenetic control and use members of the fibroblast growth factor receptor (FGF) receptor family as examples of dysregulated signals in pituitary tumorigenesis (Asa and Ezzat, 2009).

Transient pregnancy-induced Cushing's syndrome (CS) is extremely rare, with only several cases reported in the literature. Ectopic LH/hCG-receptors (LHCGR) in the adrenal gland have been suggested to be involved in the pathogenesis of this condition. We report the clinical, molecular, and genetic features of a patient with pregnancy-induced CS. A 29-year-old female patient developed CS during multiple pregnancies, leading to repeated miscarriage. Signs and symptoms of hypercortisolism resolved soon after delivery or abortion, only to recur in subsequent pregnancies. In the non-pregnant state, hCG stimulation testing resulted in elevated cortisol levels. Serum cortisol was not suppressible with dexamethasone. The adrenals exhibited bilateral adrenal cortical nodular hyperplasia. Quantitative RT-PCR revealed a 2-fold increase in LHCGR and progesterone receptor mRNA expression and decreased estrogen receptor-beta expression in the patient's adrenal tissue relative to normal adrenals. Higher intensity of immunostaining for LHCGR was observed, particularly within the nodular lesions, compared to controls. Quantitative PCR revealed a LHCGR-to-beta-actin ratio of 1.5 in genomic DNA from adrenal and peripheral leukocytes, suggesting the presence of a germline duplication of the LHCGR gene. LHCGR overexpression resulting from germline gene duplication may be a potential pathogenic mechanism underlying this case of pregnancy-induced CS.

Recent genome-wide association studies have identified fibroblast growth factor receptor (FGFR)2 as one of a few candidate genes linked with breast cancer susceptibility. In particular, the disease-predisposing allele of FGFR2 is inherited as a 7.5-kb region within intron 2 that harbors eight single nucleotide polymorphisms. The relationship between these single nucleotide polymorphisms and FGFR2 gene expression remains unclear. Here we show the common occurrence of polymorphisms within the intron 2 region in a panel of 10 breast cancer cell lines. High FGFR2-expressing cell lines such as MCF-7 cells displayed polymorphic sequences with constitutive histone acetylation at multiple intron 2 sequences harboring putative transcription binding sites. Knockdown of Runx2 or CCAAT enhancer binding protein beta in these cells resulted in diminished endogenous FGFR2 gene expression. In contrast FGFR2-negative MDA-231 cells were wild type and showed evidence of histone 3/4 deacetylation at the rs2981578, rs10736303, and rs7895676 disease-associated alleles that harbor binding sites for Runx2, estrogen receptor, and CCAAT enhancer binding protein beta, respectively. Histone deacetylation inhibition with trichostatin A resulted in enhanced acetylation at these intron 2 sites, an effect associated with robust FGFR2 reexpression. Isoform analysis proved reexpression of the FGFR2-IIIc variant the splicing of which was positively influenced by trichostatin A-mediated recruitment of the Fas-activated serine/threonine phosphoprotein survival protein. Our findings highlight the potential role of histone acetylation in modulating access to selected polymorphic sites within intron 2 as well as downstream splicing sites in generating variable FGFR2 levels and isoforms in breast cancer.

Normal epithelial cells undergo apoptosis upon detachment from the extracellular matrix, a process termed “anoikis.” However, malignant epithelial cells with metastatic potential resist anoikis and can survive in an anchorage-independent fashion. Molecules that sensitize resistant cells to anoikis will be useful chemical probes to understand this pathway. To identify novel anoikis sensitizers in anoikis-resistant PPC-1 prostate adenocarcinoma cells, a library of 2,000 off-patent drugs and natural products was screened for their ability to preferentially induce cell death in suspension over adherent culture conditions. This screen identified five members of the family of cardiac glycosides as anoikis sensitizers, including ouabain, peruvoside, digoxin, digitoxin, and strophanthidin. We conducted further studies with ouabain to discern the mechanism of cardiac glycoside-induced anoikis sensitization. Ouabain initiated anoikis through the mitochondrial pathway of caspase activation. In addition, ouabain sensitized cells to anoikis by inhibiting its known target, the Na+/K+ ATPase pump, and inducing hypoosmotic stress. Resistance to anoikis permits cancer cells to survive in the circulation and facilitates their metastasis to distant organs, so we tested the effects of Na+/K+ ATPase inhibition on distant tumor formation in mouse models. In these mouse models, ouabain inhibited tumor metastases but did not alter the growth of subcutaneous tumors. Thus, we have identified a novel mechanism to sensitize resistant cells to anoikis and decrease tumor metastasis. These results suggest a potential mechanism for the observed clinical reduction in metastasis and relapse in breast cancer patients who have undergone treatments with cardiac glycosides. [Cancer Res 2009;69(7):2739–47]

The risk of second primary malignancies (SPMs) associated with cancer therapies is an important concern of thyroid cancer survivors and physicians. Our objective was to determine if the risk of SPMs is increased in individuals with thyroid cancer treated with radioactive iodine (RAI), compared to those not treated with RAI.We performed a systematic review of the literature and meta-analysis. Two independent reviewers screened citations and reviewed full-text papers. If not reported by the primary authors, the relative risk (RR) of SPMs was calculated by dividing the standardized incidence ratio of SPM in individuals with thyroid cancer treated with RAI compared to those not treated with RAI (with associated 95% confidence intervals [CI]). The natural logarithms of RRs of respective SPMs, weighted by the inverse of the variance, were pooled using fixed effects models and the exponential of the results was reported.Two multi-center studies (one from Europe and the other from North America) were included in this review. The RR of SPMs in thyroid cancer survivors treated with RAI was significantly increased at 1.19 (95% confidence interval [CI] 1.04, 1.36, p = 0.010), relative to thyroid cancer survivors not treated with RAI (data from 16,502 individuals), using a minimum latency period of 2 to 3 years after thyroid cancer diagnosis. The RR of leukemia was also significantly increased in thyroid cancer survivors treated with RAI, with an RR of 2.5 (95% CI 1.13, 5.53, p = 0.024). We did not observe a significantly increased risk of the following cancers related to prior RAI treatment: bladder, breast, central nervous system, colon and rectum, digestive tract, stomach, pancreas, kidney (and renal pelvis), lung, or melanoma of skin.The risk of SPMs in thyroid cancer survivors treated with RAI is slightly increased compared to thyroid cancer survivors not treated with RAI.

Thyroid cancer exhibits a spectrum from relatively indolent tumors to tumors that are invasive, metastatic, or progress to poorly differentiated carcinoma. Microarray expression analysis of thyroid cancer cell lines has implicated a member of the melanoma-associated (MAGE) family of cancer–testis antigens in thyroid cancer development and progression. We performed this study to validate the role of MAGE in human thyroid cancers. A tissue microarray (TMA) of samples from 375 patients with thyroid cancer was analyzed with immunohistochemistry (IHC) to localize MAGE. Western blotting of fractionated proteins from MAGE-transfected cells was used to confirm intracellular localization of proteins. Automated analysis of TMA samples was evaluated and subjected to statistical analysis. MAGE immunoreactivity was identified in nuclear and cytoplasmic compartments of normal and malignant tissues. Specificity of staining was proved by fractionation studies that confirmed MAGE expression in nucleus and cytoplasm. Normal thyroid tissue exhibited weak cytoplasmic and strong nuclear MAGE reactivity. Tumors exhibited an increase in cytoplasmic MAGE scores that correlated with clinical behavior: larger tumors had higher MAGE scores, and there was a positive and significant correlation between MAGE cytoplasmic score and the number of histologically proven lymph node metastases. There was a statistically significant negative correlation between cytoplasmic MAGE and the percentage of p53-positive nuclei. Our data confirm gene-profiling evidence that members of the MAGE family play a role in thyroid cancer progression. The use of TMA analyses identifies IHC techniques that are translatable to the clinical setting for prognostic assessment of patients with thyroid cancer.

This review, will evaluate the experimental and clinical evidence that benign and malignant nonendocrine tumors occur as complications of acromegaly

GH is first detectable in the fetal rat pituitary between gestational days 18 and 19. The reasons for the GH surge soon after birth and subsequent postnatal decline to adult levels remain unclear. We therefore determined whether GH gene regulation in the developing pituitary could be distinguished from adult rat somatotroph function. In primary cultures of fetal and neonatal rat pituitary cells, GH secretion was detected by the 20th gestational day. These cells were stimulated by GH-releasing hormone (GHRH), but not by T3 or the morphogen retinoic acid. The stimulatory effect of T3 (0.25 mM) on GH secretion was detected only on the 2nd neonatal day and was similar to that seen in mature rat pituitary cell cultures. GHRH (10 nM) treatment for 24 h caused a 5-fold induction of GH secretion in pituitary cells derived from 2-, 5-, and 12-day-old neonatal rats. The presence or absence of T3 in the culture medium did not alter the response to GHRH. In contrast, only 2-fold induction of GH was observed in adult male pituitary cells during the same time course. Insulin-like growth factor-I (IGF-I; 6.5 nM), the peripheral target hormone for GH, resulted in a modest (20%) attenuation of GH secretion from pituitary cells derived from 20-day-old fetuses. IGF-I, however, produced a 70% reduction in GH levels in adult male pituitary cells grown under similar conditions. The effects of IGF-I on adult pituitary cells grown in T3-depleted medium were blunted. Addition of T3 partially restored the responsiveness of these cells to IGF-I. The results suggest that the high circulating GH levels in the fetal and neonatal rat may be secondary to relative insensitivity of the immature somatotroph to the inhibitory actions of IGF-I in addition to enhanced responsiveness to GHRH compared with the adult rat pituitary. Relative thyroid hormone deficiency in the immature rat may be contributory to this early transient state of pituitary IGF-I resistance.

Paragangliomas are tumors that develop from extraadrenal chromaffin cells. Approximately 20% of paragangliomas are malignant, and surgical resection is considered the primary treatment when possible. The optimal systemic treatment for advanced disease is undefined, due in part to lack of effective agents. Here we report our experience suggesting that sunitinib is an effective agent in this malignancy.Three patients with metastatic paraganglioma were treated with sunitinib at the Princess Margaret Hospital. Limited analyses of tumor tissue and germline DNA were available.Sunitinib at a standard dose (50 mg daily, 4 wk on, 2 wk off) was titrated to patient tolerance.One patient has achieved a near complete response, and two patients demonstrated partial responses. Two patients demonstrated germline defects suggesting a pseudo-hypoxic drive to the tumor whereas the third demonstrated immunohistochemical evidence of this phenomenon.Sunitinib appears to be an active agent in this malignancy based on this limited cohort, with an understandable mechanism of action similar to that described in other hypoxia-driven tumors. A single arm phase 2 trial is underway.

Epigenetically-mediated gene dysregulation is a common feature associated with human pituitary tumorigenesis. The mechanisms leading to these changes, however, remain largely unknown. In this review, we examine changes responsible for DNA and histone modifications as independent, butpotentially interrlated modes of communication effecting chromatin remodeling. The dynamic properties of the enzymes involved in these reactions is highlighted. We use the fibroblast growth factor receptor 2 (FGFR2) as a model through which the p53-regulating melanoma-associated antigen (MAGE) system is governing in pituitary cells. The pathogenetic and potential therapeutic implications are discussed.

Epigenetic dysregulation is implicated in pituitary neoplasia as the cause of silencing of several tumor suppressor genes. However, the upstream mediators of such events remain unknown.We examined the three members of the DNA methyltransferase (DNMT) enzyme family in normal and neoplastic human and mouse pituitary cells.This study was performed at a university-affiliated cancer research institute.Gene expression, promoter DNA methylation, histone modifications, and cell proliferation were determined.In contrast to DNMT1 and DNMT3a, DNMT3b was expressed at relatively higher levels in neoplastic pituitary cells. However, examination of the human DNMT3b 5' region showed uniformly low DNA methylation levels with little difference between normal and tumor samples. Through pharmacological methylation inhibition or histone deacetylation inhibition, we identified that DNMT3b gene expression is subject to histone modifications. Down-regulation of DNMT3b resulted in induction of retinoblastoma, p21, and p27, and reduction in cell proliferation. These targeted effects were associated with enhanced histone 3 acetylation and diminished histone methylation.Our findings identify DNMT3b as a putative mediator of epigenetic control through histone modifications of gene expression in pituitary cells.

Ikaros is a transcription factor that directs lymphoid lineage commitment and pituitary neuroendocrine cell expansion and function. Here, we show that Ikaros regulates the low-density lipoprotein receptor (LDL-R) to alter metabolism in pituitary corticotroph cells. The DNA-binding Ikaros isoform Ik1 binds and enhances activity of the LDL-R promoter. Ik1 decreases methylation and increases acetylation of histone H3 (Lys9) at the LDL-R promoter. Confocal microscopy and quantitative fluorometry show enhanced LDL endocytosis in Ik1-transfected cells that exhibit abundant endoplasmic reticulum, large Golgi complexes, and prominent secretory granule formation, consistent with more robust cholesterol incorporation into functionally relevant membrane-rich organelles. Consistent with these data, LDL-R−/− mice, like Ik−/− mice, have decreased circulating levels of adrenocorticotropic hormone. These findings expand the repertoire of Ikaros actions to include regulation of the cholesterol uptake metabolic pathway with therapeutic implications for lipid-modifying drugs in Ikaros-associated cancers. [Cancer Res 2008;68(10):3715–23]

Purpose: Four members of the fibroblast growth factor receptor (FGFR) family transduce signals of a diverse group of FGF ligands. The FGFR2-IIIb isoform is abundantly present in the normal pituitary gland with contrasting down-regulation in neoplastic pituitary cells. cDNA profiling identified the cancer-testis antigen melanoma-associated antigen A3 (MAGE-A3) as a putative target negatively regulated by FGFR2. Experimental Design: Comparisons were made between normal and neoplastic human and mouse pituitary cells. Gene expression was examined by reverse transcription-PCR, DNA methylation was determined by methylation-specific PCR and combined bisulfite restriction analysis, and histone modification marks were identified by chromatin immunoprecipitation. Results: Normal human pituitary tissue that expresses FGFR2-IIIb does not express MAGE-A3; in contrast, pituitary tumors that are FGFR2 negative show abundant MAGE-A3 mRNA expression. MAGE-A3 expression correlates with the presence and extent of DNA promoter methylation; more frequent and higher-degree methylation is present in the normal gland compared with pituitary tumors. Conversely, pituitary tumors are hypomethylated, particularly in females where MAGE-A3 expression is nearly thrice higher than in males. Estradiol treatment induces MAGE-A3 through enhanced histone 3 acetylation and diminished methylation. The effects of estradiol are directly opposed by FGF7/FGFR2-IIIb. Down-regulation of MAGE-A3 results in p53 transcriptional induction, also through reciprocal histone acetylation and methylation modifications. Conclusions: These findings highlight MAGE-A3 as a target of FGFR2-IIIb and estrogen action and provide evidence for a common histone-modifying network in the control of the balance between opposing signals.