Immunohistochemical examination of pituitary adenomas. Comparison to clinical and endocrinological findings

A comparison was made with the data of 62 cases of pituitary adenoma, evaluated pre- and postoperatively, including as well the results of immunohistochemical hormone examination (also for calcitonin). Prolactin was found in 18 of the 21 adenomas carrying the preoperative diagnosis of prolactinoma, whereas cells containing other hormones (growth hormone, LH, FSH, TSH, ACTH, beta-endorphin), were only occasionally present. The growth hormone was strongly positive in the adenoma tissue in 16 of the 17 cases of acromegaly. 5 of these adenomas were accompanied by a marked hyperprolactinemia and also contained many prolactin cells. 6 of the 19 adenomas diagnosed as being 'inactive' contained hormone-positive cells, but only a very small number of cells. ACTH was found in 3 of the 4 pituitary adenomas of patients with Cushing's disease. 2 of these were also positive for beta-endorphin. The tissue of 1 gonadotrophic adenoma (with elevated FSH in serum) gave positive results with an anti-LH antiserum. Calcitonin was not found in any adenoma. The preoperative serum prolactin levels did not quantitatively correlate with the percentage of prolactin-positive cells.     

HIF-1α 在垂体腺瘤中的表达及与垂体腺瘤侵袭性的关系

目的:研究缺氧诱导因子-1α(HIF-1α)在人垂体腺瘤中的表达,对HIF-1α蛋白表达与肿瘤分级进行相关性分析,探讨其表达水平与垂体腺瘤侵袭性的关系.方法:集影像学检查、内分泌学检查及病理诊断的垂体腺瘤60例,分为侵袭组和非侵袭组,其中侵袭组36例,非侵袭组24例;对照组正常脑组织5例.免疫组织化学技术检测HIF-1α蛋白的表达,结合临床资料进行统计学分析.分析垂体腺瘤HIF-1α蛋白的表达水平并与对照组进行比较,比较侵袭组和非侵袭组垂体腺瘤之间HIF-1α蛋白表达水平的差异.结果:HIF-1α蛋白在垂体腺瘤中的表达明显高于对照组,二者比较,x20.05,1=12.392,P＜0.001,有显著性差异;侵袭组HIF-1α蛋白的表达较非侵袭组显著增高,二者比较,x20.05.1=24.658,P＜0.001,有显著性差异.结论:H1F-1α是垂体腺瘤侵袭过程中的重要调控因子,与垂体腺瘤的大小、分级以及侵袭性密切相关,其作用机制有待进一步研究,其表达程度可用作垂体腺瘤预后的评估指标,为垂体腺瘤术后的复发以及相应的辅助治疗提供判断依据.有可能为人们靶向肿瘤缺氧来开发新药物提供新的作用靶点.     

Responses of the ultimobranchial body in eels (Anguilla anguilla L.) maintained in sea water and experimentally matured,to injections of synthetic salmon calcitonin

The effect of a synthetic salmon calcitonin (SCT) treatment on ultimobranchial body (UB) activity in eels (Anguilla anguilla L.) maintained in seawater and submitted to experimental maturation, has been studied histologically. 2. The activity of the glands of a control group of eels maintained in sea water was taken as a reference. 3. The UB parenchyma showed a marked atrophy in the fish treated with SCT alone and serum calcium decreased significantly in this group. 4. Immature female silver eels receiving carp pituitary extract (CPE 1 mg/100 g body wt. per injections) until complete maturation presented high hypercalcemia associated with cellular hypertrophy and hyperplasia in the UB. 5. SCT treatment did not prevent the hypercalcemia provoked by CPE injections. UB activity was strongly increased in this case. 6. These data indicate that the activity of the UB in eels varies with both physiological and experimental hypercalcemia, and responds to SCT injections.     

Phenotypical and Pharmacological Characterization of Stem-Like Cells in Human Pituitary Adenomas

The presence and functional role of tumor stem cells in benign tumors, and in human pituitary adenomas in particular, is a debated issue that still lacks a definitive formal demonstration. Fifty-six surgical specimens of human pituitary adenomas were processed to establish tumor stem-like cultures by selection and expansion in stem cell-permissive medium or isolating CD133-expressing cells. Phenotypic and functional characterization of these cells was performed (1) ex vivo, by immunohistochemistry analysis on paraffin-embedded tissues; (2) in vitro, attesting marker expression, proliferation, self-renewal, differentiation, and drug sensitivity; and (3) in vivo, using a zebrafish model. Within pituitary adenomas, we identified rare cell populations expressing stem cell markers but not pituitary hormones; we isolated and expanded in vitro these cells, obtaining fibroblast-free, stem-like cultures from 38 pituitary adenoma samples. These cells grow as spheroids, express stem cell markers (Oct4, Sox2, CD133, and nestin), show sustained in vitro proliferation as compared to primary cultures of differentiated pituitary adenoma cells, and are able to differentiate in hormone-expressing pituitary cells. Besides, pituisphere cells, apparently not tumorigenic in mice, engrafted in zebrafish embryos, inducing pro-angiogenic and invasive responses. Finally, pituitary adenoma stem-like cells express regulatory pituitary receptors (D2R, SSTR2, and SSTR5), whose activation by a dopamine/somatostatin chimeric agonist exerts antiproliferative effects. In conclusion, we provide evidence that human pituitary adenomas contain a subpopulation fulfilling biological and phenotypical signatures of tumor stem cells that may represent novel therapeutic targets for therapy-resistant tumors.     

GSTP1、E-cadherin在垂体腺瘤中的表达及临床意义

目的：研究谷胱甘肽S-转移酶P1（GSTP1）、上皮钙粘蛋白（E-cadherin）在垂体腺瘤中的表达及临床意义。方法：应用免疫组化SP染色法检测30例侵袭性垂体腺瘤与30例非侵袭性垂体腺瘤中GSTP1、E-cadherin的表达。结果：GSTP1在侵袭性垂体腺瘤中的表达较非侵袭性垂体腺瘤显著降低（P〈0.05）;E-cadherin在侵袭性垂体腺瘤中的表达较非侵袭性垂体腺瘤显著降低（P〈0.05）;GSTP1、E-cadherin在垂体腺瘤中的表达呈正相关（r=0.82,P〈0.05）。结论：GSTP1、E-cadherin在垂体腺瘤中的表达与肿瘤侵袭程度显著相关,两者联合检测有助于判断垂体腺瘤侵袭性及预后。     

Proliferating cell nuclear antigen (PCNA) expression in pituitary adenomas: relationship to the endocrine phenotype of adenoma

The expression of proliferating cell nuclear antigen (PCNA) correlates to cell proliferation and for this reason it is commonly considered as one of proliferation markers. Since proliferation rate is an important factor determining the tumor aggressiveness, the evaluation of PCNA index (the percentage of PCNA-immunopositive nuclei in the investigated tumor sample) is suggested as useful in predicting pituitary adenoma outcome. Seventy three unselected, surgically removed pituitary adenomas were immunostained with antibodies against the pituitary hormones or their subunits and against the proliferating cell nuclear antigen (PCNA). The highest PCNA index was found in ACTH-immunopositive tumors without the manifestation of the Cushing's disease ("silent" corticotropinomas). This value was significantly different in comparison to other adenoma subtypes including corticotropinomas manifesting themselves by Cushing's disease. The lowest PCNA index was noticed in monohormonal GH-secreting tumors. The adenomas which express more than one hormone (plurihormonal adenomas) seem to have a higher PCNA indices than monohormonal ones; the difference was significant in the case of mono- and plurihormonal prolactinomas. The recurrent tumors presented a higher mean PCNA index as compared to the primary tumors, although the difference was significant only in the case of prolactinomas. These findings suggest that the proliferative potential of pituitary adenomas is related to the tumor recurrence and hormone expression.     

鞍区常见肿瘤影像学诊断现状

鞍区占位包括垂体起源的和非垂体起源的占位性病变,其中以垂体腺瘤最为常见。由于鞍区其他占位性病变在颅内的解剖位置与垂体腺瘤十分接近,因此垂体腺瘤的诊断与鞍区其它肿瘤的鉴别诊断,是影像科医师所面临的挑战。将鞍区其它少见的占位性病变与垂体腺瘤相鉴别,给出正确的诊断对于指导临床手术入路和避免术中和术后出现并发症(如脑脊液漏、颅内感染),具有重要意义。其中鞍区占位性病变常需要将垂体腺瘤与Rathke囊肿、颅咽管瘤、鞍区脑膜瘤、脊索瘤、颅内转移瘤相鉴别。本文总结了目前垂体腺瘤等其他占位性病变的影像学表现以及影像学特征,以便于鞍区常见肿瘤的诊断和鉴别诊断。     

Identification of DLK1 variants in pituitary- and neuroendocrine tumors

In a gene chip analysis of common pituitary tumor types, one of the genes with the most impressive tissue-specific expression regulation was delta-like 1 (DLK1), which was strongly expressed in GH-secreting (GH-S) pituitary tumors. In addition to pituitary adenomas, various endocrine tumors were subjected to real-time-quantitative PCR revealing high expression of DLK1 in normal pituitary tissue, in GH-S-, in one prolactin-secreting pituitary adenoma and in pheochromocytomas. Additionally, three DLK1 gene-derived subvariants were identified. The first, lacking 204 bp--coding for epidermal growth factor-like domain 6 and parts of the juxtamembrane region--was named Secredeltin. In the other two splice variants (named Brevideltin and Brevideltinin), a stop codon is introduced due to a frame-shift, leading to truncated proteins of 204 and 213 aas, respectively.     

miR-134在人垂体腺瘤组织中的表达及其意义(英文)

目的:探讨垂体腺瘤患者miR-134的表达及意义,分析其表达水平与无功能垂体腺瘤(non-functioningpituitaryadenomas,NFPA)增殖侵袭能力的相关性。方法:选择2010年6月至2013年7月本院收集垂体腺瘤标本104例以及8例尸检正常腺垂体的临床资料。采用实时荧光定量PCR、免疫组织化学技术检测Ki-67、MEG3、miR-134等在NFPA组织中的表达水平,并分析数据。结果:miR-134在NFPA组织中表达水平显著低于正常腺垂体和其他类型垂体腺瘤(P0.01);miR-134的表达水平与NFPA患者肿瘤侵袭性、肿瘤细胞Ki-67阳性率及发病年龄呈负相关(P0.01)。结论:miR-134表达下调可能是NFPA肿瘤发生及肿瘤呈侵袭样生长的重要因素,miR-134可作为诊断和评估NFPA预后的参考指标。     

Identification of differentially expressed microRNAs by microarray: a possible role for microRNA genes in pituitary adenomas

MicroRNAs (miRNAs) are small non-coding RNAs that control gene expression by targeting mRNA. It has been demonstrated that miRNA expression is altered in many human cancers, suggesting that they may play a role in human neoplasia. To determine whether miRNA expression is altered in pituitary adenomas, we analyzed the entire miRNAome in 32 pituitary adenomas and in 6 normal pituitary samples by microarray and by Real-Time PCR. Here, we show that 30 miRNAs are differentially expressed between normal pituitary and pituitary adenomas. Moreover, 24 miRNAs were identified as a predictive signature of pituitary adenoma and 29 miRNAs were able to predict pituitary adenoma histotype. miRNA expression could differentiate micro- from macro-adenomas and treated from non-treated patient samples. Several of the identified miRNAs are involved in cell proliferation and apoptosis, suggesting that their deregulated expression may be involved in pituitary tumorigenesis. Predictive miRNAs could be potentially useful diagnostic markers, improving the classification of pituitary adenomas.     

Immunocytochemical study of S-100 protein in human pituitary adenomas

The S-100 protein was localized by immunocytochemistry in 70 pituitary tumors including 30 prolactin, 16 growth hormone, two corticotropin and 22 non-functioning adenomas. Positive immunostaining was observed in only one case (prolactin adenoma). It is concluded that in functioning and non-functioning pituitary tumors there is no particular involvement of S-100 protein-containing cells, at least under the conditions of this study.     

Neuronal differentiation and expression of neural epitopes in pituitary adenomas.

Neural transdifferentiation is increasingly recognized in neural crest and neural stem cell tumors. Neuronal differentiation has been anecdotally described primarily in somatotroph cell adenomas associated with acromegaly, but its prevalence in adenomas and relationship to adenoma type has not been completely established. In this study we performed a retrospective morphological and immunohistochemical analysis of neurofilament, phosphoneurofilament, Neu-N, class III tubulin, and Hu in WHO grade I pituitary adenomas. Limited numbers of cells with neuronal features and neuron-associated epitopes may be more common in pituitary adenomas than previously recognized. These may occur in many forms of adenomas including somatotroph, lactotroph, mixed somatotroph and lactotroph, null cell/gonadotroph cell and, rarely, corticotroph cell adenomas.     

垂体瘤微环境免疫细胞浸润与肿瘤侵袭性的相关性研究

目的:探讨垂体瘤免疫微环境中免疫细胞浸润情况及其与垂体瘤侵袭性的相关性。方法:选取35例垂体瘤病理组织切片,通过免疫组化染色分析巨噬细胞、T细胞以及中性粒细胞的特异性标记蛋白CD68、CD4、CD8和MPO的表达情况。结合临床和影像学数据分析,分析生长激素腺瘤、泌乳素腺瘤和无功能腺瘤的侵袭性与免疫细胞浸润数量的相关性。结果:在15例生长激素腺瘤,10例泌乳素腺瘤和10例无功能性腺瘤患者中,侵袭性垂体瘤中有更多的巨噬细胞浸润(P分别为0.014,0.032和0.032)。侵袭性促生长激素腺瘤、泌乳素腺瘤和无功能性腺瘤巨噬细胞浸润数量均明显多于非侵袭性促生长激素腺瘤、泌乳素腺瘤和无功能性腺瘤(P0.05)。结论:在垂体腺瘤中,巨噬细胞是肿瘤免疫微环境的主体。巨噬细胞浸润可能促进垂体瘤的进展。     

The Min (multiple intestinal neoplasia) mutation: its effect on gut epithelial cell differentiation and interaction with a modifier system

Min is a fully penetrant dominant mutation that leads to the development of multiple intestinal adenomas throughout the duodenal-to-colonic axis. Min/+ C57BL6/J mice have an average life-span of 120 d. Multi-label immunocytochemical studies of these lesions demonstrate patches of differentiated enterocytes, and scattered enteroendocrine, goblet and Paneth cells. Expression of endogenous marker genes within these differentiated cells can be directly correlated with the position occupied by the adenoma along the duodenal-to-colonic axis and mirrors the regional differentiation of the normal gut epithelium. The presence of multiple lineages in adenomas together with their retention of spatial information suggests that tumorigenesis in Min/+ mice may be initiated in a multipotent stem cell normally located at the base of intestinal crypts. To study the time-dependent properties of these tumors, genetic conditions were sought in which Min/+ animals could survive for up to 300 d. Min is fully penetrant in hybrids with either AKR/J or MA/MyJ. However, the hybrids demonstrate a reduction in the number of intestinal adenomas. Preliminary backcross analysis is consistent with a single major modifier locus unlinked to Min in both the AKR/J and MA/MyJ strains. The increased lifespan of the hybrid animals is also associated with the development of invasive tumors. New tumors do not arise continuously over the lifespan of these animals; instead all adenomas appear to be established by 100 d of age or sooner. These studies indicate that the Min/+ mouse is a powerful model system for analyzing the mechanisms that establish and maintain a balance between proliferation and differentiation in the continuously renewing gut epithelium and for an assessment of the multi-step hypothesis of intestinal neoplasia.     

MiR-26a在人垂体腺瘤组织及血清中表达的研究

目的：miRNA遍及生命体的发生、发育、分化和死亡的过程。它在肿瘤、心血管、糖尿病等多种疾病的各个阶段中起到调控癌基因作用。miRNA在垂体腺瘤中异常表达,且影响垂体腺瘤的增殖、侵袭及凋亡情况。本研究通过探讨miRNA家族中的miR-26a在垂体腺瘤组织及血清中的表达变化情况,为垂体瘤的早期诊断及疗效监测提供依据,以便更好的指导临床诊断及治疗工作。方法：收集哈尔滨医科大学附属第四医院微创神经外科手术切除并经病理证实的垂体腺瘤20例,取其组织及采集血清标本：年龄在20-74岁（平均50岁）,术前均未进行任何治疗。既往无内分泌疾病的正常死亡人的垂体组织及其血清标本20例作为对照组。采用实时定量聚合酶链式反应（Real-timePCR）方法分别检测垂体腺瘤病人和正常人组织及血清中的miRNA-26a的表达情况。用SPSSl3．0统计分析软件运用Mann—WhitneyU检验方法对数据进行统计学分析。结果：miRNA-26a在垂体腺瘤组织中的表达量为22．30,正常垂体组织中的表达量为23．38,垂体腺瘤患者血清中miRNA-26a的表达表达量为25．04,正常对照组血清中的表达量为24．95,垂体腺瘤组织中的表达较正常垂体组织中的表达明显升高（P〈0．05）,垂体腺瘤患者血清与正常人血清中miRNA-26a的表达无明显差异（P〉0．05）。结论：垂体腺瘤组织中miRNA-26a的高表达与血清学检测miRNA-26a的正常表达,为预防脑垂体腺瘤的发生和发展提供了重要的临床诊断依据。     

Subhypothalamic grafts of human pituitary adenomas in total-body irradiated rats

Summary Human pituitary adenomas proliferate neither in cell culture nor in athymic nude mice. We propose that one or several of the humoral factors necessary for the growth of pituitary adenomas is missing in these experimental environments. The purpose of our experiments was to examine the possible influence of the hypothalamus in supporting cellular proliferation, and thus adenoma growth. Fragments from four human pituitary adenomas (three pituitary prolactinomas; one ACTH-secreting adenoma) were transplanted into the pituitary fossa of total-body irradiated, hypophysectomized rats. The rats were killed after two weeks and perfused with a mixture of formalin and India ink. Histologic examination of serial sagittal sections through the pituitary fossa and the adjacent brain showed: vascularization of the grafts from the pituitary stalk and from the scar tissue in the sphenoid bone; survival of some adenomas; and numerous mitoses in an ACTH-secreting specimen obtained from a patient who had Cushing's disease. We conclude from these experiments that as yet unidentified hypothalamic factors are essential for the growth of certain types of pituitary adenomas.This study was supported by a grant to Dr. Landolt from the Jubiläumsspende of the University of Zürich, Switzerland.The results were presented in part at the Second European Workshop on Pituitary Adenomas, Paris, September 20–22, 1979     

Paradoxical acute hypercalcemic effect of salmon calcitonin in patients having Paget's disease of bone after treatment with dichloromethylene diphosphonate

The hypocalcemia following administration of calcitonin may be an index to disease activity in Paget's disease of bone. Therefore, we assessed the effect of a single injection of 100 MRC units of salmon calcitonin (SCT) on plasma calcium in 28 patients with active Paget's disease before and after 6 months of treatment with dichloromethylene diphosphonate (Cl2MDP) at a dose of 400 mg/day (3 patients), 800 mg/day (8 patients), 1.600 mg/day (9 patients) or 2.600 mg/day (8 patients). The mean SCT-induced hypocalcemia was reduced by Cl2MDP and there was a significant positive correlation between the decrease of serum calcium induced by SCT and bone resorption evaluated by the number of osteoclasts on bone biopsy taken in pagetic iliac crest. After Cl2MCP treatment, 5 patients manifested a paradoxical hypercalcemic response to SCT injection ranging from +0.3 mg/dl to +0.5 mg/dl, which was sustained over the 9 hours following injection. As these patients had a dramatic inhibition of bone resorption induced by Cl2 MDP, it is suggested that the hypercalcemic response to SCT might reflect persistence or exaggeration of the early hypercalcemic effect of CT which reportedly precedes the hypocalcemic response to SCT.     

The effect of calcitonin on prolactin secretion during gestation

The relationship between calcitonin (CT) and prolactin (PRL) was studied by means of the injection of salmon calcitonin (SCT) i.p. on day 1 of gestation. An estrogen inhibitor - clomiphene - was also administered to certain groups of animals on day 4 and 5 of gestation. SCT did not affect PRL levels on day 1 of gestation nor on days 5 or 7, but it prevented the rise of PRL levels observed in animals submitted to injection stress on days 4 and 5. In animals treated with clomiphene, the inhibition by SCT on PRL increase after injection stress was partially abolished. SCT while not affecting basal PRL level prevented the rise observed after stress and this effect occurred some days later. Thus SCT could exercise a delayed neuroendocrine control. This action of SCT seemed to be partially dependent upon the presence of estrogens.     

Morphogenesis and significance of fibrous bodies in human pituitary adenomas

In the course of light and electron microscopic studies of 142 surgically-removed human pituitary adenomas, 28 tumors were found containing fibrous bodies composed of type II microfilaments with an average width of 115A. These spherical structures, measuring up to 4-5 micrometer occur exclusively in sparsely granulated growth hormone cells and acidophil stem cells, but as revealed by the immunoperoxidase technique, contain no growth hormone. Fibrous bodies are located in the Golgi region and are consistently associated with Golgi membranes and smooth-surfaced endoplasmic reticulum. Their association with centrioles is thought to be anatomical rather than functional. Several adenoma cells possess spherical formations composed entirely of smooth-walled membranes or transitional forms between smooth tubules and type II microfilaments, suggesting that smooth membranes may play a key role in the production of fibrillar substance. Fibrous bodies appear to be reliable morphologic markers and are valuable in the differential diagnosis of pituitary adenomas.     

Early multipotential pituitary focal hyperplasia in the alpha-subunit of glycoprotein hormone-driven pituitary tumor-transforming gene transgenic mice

Pituitary tumor-transforming gene (PTTG), a securin protein isolated from pituitary tumor cell lines, is highly expressed in invasive tumors and exhibits characteristics of a transforming gene. To determine the role of PTTG in pituitary tumorigenesis, transgenic human PTTG1 was targeted to the mouse pituitary using the alpha-subunit of glycoprotein hormone. Males showed plurihormonal focal pituitary transgene expression with LH-, TSH-, and, unexpectedly, also GH-cell focal hyperplasia and adenoma, associated with increased serum LH, GH, testosterone, and/or IGF-I levels. MRI revealed both pituitary and prostate enlargement at 9-12 months. Urinary obstruction caused by prostatic hyperplasia and seminal vesicle hyperplasia, with renal tract inflammation, resulted in death by 10 months in some animals. Pituitary PTTG expression results in plurihormonal hyperplasia and hormone-secreting microadenomas with profound peripheral growth-stimulatory effects on the prostate and urinary tract. These results provide evidence for early pituitary plasticity, whereby PTTG overexpression results in a phenotype switch in early pituitary stem cells and promotes differentiated polyhormonal cell focal expansion.