Dedifferentiation of enterochromaffin-like cells in gastric cancer of hypergastrinemic cotton rats

The role of enterochromaffin-like (ECL) cells in gastric carcinogenesis is not fully understood. Spontaneous tumours developing in hypergastrinemic female cotton rats have an adenocarcinoma phenotype, but numerous cells in the dysplastic mucosa as well as in the carcinomas are positive for neuroendocrine markers. In the present study of female cotton rats with 2 and 8 months' hypergastrinemia, the oxyntic mucosa of the stomach was examined histologically and immunolabelled for histidine decarboxylase (HDC) and pancreastatin, and hyperplastic and neoplastic ECL cells were evaluated by electron microscopy. These animals developed hyperplasia of the oxyntic mucosa in general and of the ECL cells in particular after 2 months and dysplasia and carcinomas after 8 months. The immunoreactivity of the ECL cells in the oxyntic mucosa was increased at 2 months and declined at 8 months. These histological changes were associated with progressive loss of secretory vesicles and granules in ECL cells. We suggest that ECL cells in hypergastrinemic cotton rats dedifferentiate with time and that the gastric carcinomas may develop from ECL cells.     

Ghrelin expression in normal kidney tissue and renal carcinomas

Ghrelin expression in cancers is either reduced/absent or increased depending on the organs involved. The aims of this study were to investigate: (i) whether there are differences in ghrelin peptide expression between kidney tissues from a series of renal cell carcinoma cases, oncocytomas, and normal controls; (ii) whether there are correlations between tissue ghrelin levels in a series of renal carcinoma cases and normal controls; and (iii) how normal is kidney ghrelin expression per mg tissue as compared with the normal stomach tissue ghrelin level. We studied 7 normal stomach and 7 normal kidney samples, 21 clear cell renal carcinomas, 7 chromophobe type renal cell carcinomas (RCC), 7 papillary type RCC, and 7 oncocytoma samples. Tissue ghrelin expression was measured by RIA and immunohistochemistry. Grades 1–3 clear renal cell carcinomas, chromophobe type RCC, papillary type RCC, and oncocytomas expressed 88%, 94%, 95%, 51%, 75%, and 48% less ghrelin than the normal kidney, respectively. Overall, we concluded that ghrelin expression in renal cell carcinoma tissues is always lower than that in normal kidney or is absent. This low level or lack of ghrelin may play a role in the etiopathogenesis and progression of cancer.     

Warthin-Finkeldey-like cells in benign and malignant lymphoid proliferations

Multinucleate giant cells resembling Warthin-Finkeldey cells have been described in various lymphoid disorders. These Warthin-Finkeldey-like cells (WFLC) with as many as 50 nuclei are of three main types: reticular, lymphocyte and intermediary. In reactive lymphoid proliferations (34 cases) WFLC were mainly observed inside germinal centres and to a lesser extent in the interfollicular zones. In neoplastic lymphoid proliferations (33 cases) WFLC were most commonly found in the lymphocytic predominance type of Hodgkin's disease (16/25 cases). All non-Hodgkin's lymphomas (13 cases) in which WFLC were detected proved to be of low grade malignancy (lymphocytic: one case, lymphoplasmacytic-plasmacytoid: six cases; and centroblastic-centrocytic, six cases). They were also found in two cases of angioimmunoblastic lymphadenopathy. Immunoperoxidase and electron microscopic studies could not elucidate the exact histogenesis of these cells, but it is assumed that they are associated with B cell proliferations.     

Galectin-3 expression in normal,hyperplastic, and neoplastic endometrial tissues

This study evaluated the expression of galectin-3 in 101 curettage specimens from normal, hyperplastic, and neoplastic endometrial tissues using immunohistochemistry. The histologic diagnoses were as follows: normal proliferative (n = 8) and secretory (n = 4) phase, simple hyperplasia (SH, n = 16), complex hyperplasia without atypia (CH, n = 11), atypical hyperplasia (AH, n = 13), endometrioid adenocarcinoma (EC, n = 35), serous papillary carcinoma (SPC, n = 10), and clear cell carcinoma (CC, n = 4). Immunostaining was scored with regard to the approximate percentage of positive tumor cells and relative staining intensity. The scores of immunostaining increased significantly from NE, SH, CH, and AH to the adenocarcinomas (ANOVA, p < 0.0001). Subsequently, three significantly different levels of galectin-3 expression were found (Newman-Keuls multiple comparison test). These consisted of (a) NE, SH, and CH, (b) AH and EC, and (c) SPC and CC. Galectin-3 expression increased with tumor grade (ANOVA, p = 0.0026). The scores of FIGO stages I to III did not differ significantly (ANOVA, p = 0.1687). Enhanced nuclear galectin-3 expression was noted in carcinomas, immunostaining of stromal cells decreased in the latter. This study shows that galectin-3 expression increases from normal and hyperplastic to atypical hyperplastic and cancerous states of endometrial tissues, and provides further evidence of a relationship between AH and EC.     

An Unusual Case of Multiple Gastric Carcinoids Associated with Diffuse Endocrine Cell Hyperplasia and Parietal Cell Hypertrophy

We describe a case of multiple gastric carcinoid tumors in a 47-year-old Japanese man. The patient had markedly elevated serum gastrin levels (>800 pg/mL), which were suppressed by secretin-pancreozymin administration. In the partial gastrectomy specimen, a total of 19 carcinoids arose from diffuse linear and micronodular hyperplasia of the oxyntic mucosal endocrine cells. The carcinoid cells were chromogranin A-positive. Except for a very small number of serotonin-positive cells in several carcinoids, none of the 19 reacted with a battery of antibodies to other bioactive neuroendocrine substances. The most prominent findings in this case were peculiar fundic glands that were distended with a proteinaceous substance and lined with large hypertrophic parietal cells. At the ultrastructural level, these cells showed poorly developed intracytoplasmic canaliculi and vesicotubular profiles, yet their large cytoplasm had numerous mitochondria. On the basis of our histological and ultrastructural findings we suggest that an intrinsic HCl secretion abnormality of the parietal cells may be responsible for the patient's hypergastrinemia. Since there have been no reports on similar parietal cells changes, it is possible that our case may represent a pathological entity not previously described.     

Ghrelin对棕榈酸诱导的内皮细胞凋亡的影响及机制

 目的 探讨ghrelin能否抑制棕榈酸诱导的大鼠主动脉内皮细胞凋亡及其与PI3K/Akt通路的关系。 方法 大鼠主动脉内皮细胞在分别在含或不含0.3mM棕榈酸的DMEM培养基中孵育,培养基中加或不加ghrelin及PI3K/Akt的阻断剂LY294002,流式细胞仪Annexin Ⅴ/PI法检测凋亡,分光光度计检测caspase-3活性,Western blot检测总Akt及磷酸化Akt。 结果0.3mM棕榈酸作用24小时增加大鼠主动脉内皮细胞凋亡,Ghrelin抑制棕榈酸诱导的内皮细胞凋亡。棕榈酸干预内皮细胞24小时能显著抑制Akt的磷酸化,加入ghrelin可引起Akt的活化。Ghrelin引起的Akt的活化能够显著地被PI3K/Akt阻断剂LY294002所阻断,而且LY294002能够阻断ghrelin对棕榈酸诱导的内皮细胞凋亡的保护作用。 结论 Ghrelin能够抑制棕榈酸诱导的大鼠主动脉内皮细胞凋亡,ghrelin的抗凋亡作用至少是部分通过PI3K/Akt通路起作用的。     

Adrenomedullin, Bcl-2 and microvessel density in normal, hyperplastic and neoplastic endometrium

Adrenomedullin (ADM) is a multifunctional 52-amino acid peptide involved in numerous physiological and pathological processes, including angiogenesis, growth regulation, differentiation, and vasodilation. ADM is thought to act through the G protein-coupled receptor calcitonin receptor-like receptor, with specificity being conferred by receptor-associated modifying protein 2. The aim of the present study was to clarify the roles of ADM status, and tumor vessels in endometrium. Specimens were examined for ADM, microvessel density (MVD), area of venules (AV) and Bcl-2 oncoprotein using an immunoperoxidase method. The difference of ADM between normal proliferative phase and hyperplasia without atypia was significant ( P < 0.05). The level of Bcl-2 was significantly different between hyperplasia without atypia and hyperplasia with atypia ( P < 0.05). ADM, MVD and AV in the endometrium increased in a stepwise manner from normal, simple or complex hyperplasia with or without atypia to grade 1 adenocarcinoma. In contrast, expression of Bcl-2 oncoprotein was decreased. These parameters identify the role of ADM expression and Bcl-2 protein in relation to cell growth and vasodilating in the neoplastic changes.     

Ghrelin对血管紧张素Ⅱ诱导的人脐静脉内皮细胞损伤保护作用的研究

目的研究促生长激素释放肽Ghrelin对血管紧张素Ⅱ（AngⅡ）体外诱导人脐静脉内皮细胞（HUVECs）损伤的保护作用。方法体外培养的HuVEcs，随机分为6组：正常对照组；Ghrelin（10^-7mol／L）组；AngⅡ（10^-7mol／L）组；AngⅡ（10^-7mol／L）＋Ghrelin不同浓度组：（Ghrelin 10^-7mol／L、10^-7mol／L和10^-7mol／L三个浓度组）。每组设6个复孔。用AngⅡ和Ghrelin联合干预细胞18h后，采用放射免疫方法测定内皮素-1（ET-1）含量；硝酸还原酶法测定一氧化氮（NO）含量；流式细胞仪检测细胞内活性氧（ROS）水平。结果Ghrelin呈浓度依赖性地显著减少AngⅡ诱导人脐静脉内皮细胞的ROS生成及ET-1释放，且明显促进NO生成（P〈0．05）。结论Ghrelin对AngⅡ体外诱导的HUVECs损伤有保护作用。     

G‐cell hyperplasia of the stomach induces ECL‐cell proliferation in the pyloric glands in a paracrinal manner

An inhibitory mechanism toward gastrin hypersecretion is significantly different between G‐cell hyperplasia and gastrinoma despite the common clinical manifestations; hypergastrinemia and its related persistent gastric ulcers. We recenlty studied the G‐cell, d ‐cell and ECL‐cell density in a case of G‐cell hyperplasia. The 70‐year‐old patient has been treated for persistent gastric ulcers with a markedly increased plasma gastrin (5600 pg/mL). The stomach was surgically resected because of the obstruction associated with ulcer scars. The number of G‐cells in the pyloric glands was quantified on the surgical specimens and G‐cell hyperplasia was histolopathologically identified. Immunostainig of histidine decarboxylate revealed the presence of ECL‐cell hyperplasia in the pyloric glands and its density was significantly and positively correlated with G‐cell density. Somatostatin immunoreactive cells (d ‐cells) increased in their number in the oxyntic glands. These results all indicated that hypersecretion of gastrin in G‐cell hyperplasia could induce ECL‐cell proliferation in a paracrinal manner. In addition, relatively non‐prominent endocrinological features in the G‐cell hyperplasia compared to gastrinoma could be also related to the paracrinal somatostatin inhibitory effects upon ECL‐cells in the pyloric glands.     

乳腺导管内增生性病变及浸润性癌中树突状细胞的检测

目的　检测乳腺导管内增生性病变和微小浸润性癌及浸润性导管癌中树突状细胞(dendriticcells,DC)和T细胞的 分布状况和浸润密度,探讨乳腺癌发生、发展中机体免疫状态的变化规律。方法　应用免疫组化S P法和两步法对16例正常 副乳腺、58例导管内增生性病变、4例微浸润导管癌及67例浸润性导管癌乳腺标本进行S 100蛋白+DC、HLA DR+DC、CD1a +DC(DC三参数)及CD45RO+T细胞的浸润密度检测。结果　浸润癌中DC三参数浸润密度均高于其它病变组织(P< 0.05)。导管原位癌、微浸润癌及浸润癌组织中CD45RO+T细胞浸润密度均高于其它病变组织(P<0.05)。DC三参数间及 其与CD45RO+T细胞间均呈正相关(P<0.001)。结论　DC浸润密度随增生性病变加重而逐渐增高,发展为浸润癌时则明 显增高。     

Ghrelin increases intracellular Ca(2+) concentration in the various hormone-producing cell types of the rat pituitary gland

Ghrelin, isolated from the stomach as an endogenous ligand for the growth hormone secretagogue receptor (GHS-R), has potent growth hormone release ability in vivo and in vitro. Although GHS-R is abundantly expressed in the pituitary gland, there is no direct evidence of a relationship between hormone-producing cells and functional GHS-R in the pituitary gland. The aim of this study was to determine which anterior pituitary cells respond to ghrelin stimulation in male rats. We performed Fura-2 Ca(2+) imaging analysis using isolated pituitary cells, and performed immunocytochemistry to identify the type of pituitary hormone-producing cells. In Fura-2 Ca(2+) imaging analysis, ghrelin administration increased the intracellular Ca(2+) concentration in approximately 50% of total isolated anterior pituitary cells, and 20% of these cells strongly responded to ghrelin. Immunocytochemical analysis revealed that 82.9±1.3% of cells that responded to ghrelin stimulation were GH-immunopositive. On the other hand, PRL-, LH-, and ACTH-immunopositive cells constituted 2.0±0.3%, 12.6±0.3%, and 2.5±0.8% of ghrelin-responding pituitary cells, respectively. TSH-immunopositive cells did not respond to ghrelin treatment. These results suggest that ghrelin directly acts not only on somatotrophs, but also on mammotrophs, gonadotrophs, and corticotrophs in the rat pituitary gland.     

Cyclooxygenase-2 in normal,hyperplastic and neoplastic follicular cells of the human thyroid gland

This study was undertaken to investigate cyclooxygenase-2 (COX-2) expression in follicular cells of the human thyroid. COX-2 expression was studied immunohistochemically in a total of 174 samples. COX-2 immunoreactivity was confined to the cell cytoplasm with the nuclei remaining unlabelled. COX-2 expression was observed in five cases (17.2%) of normal follicular cells and in one case (16.6%) of solid cell nests. Follicular carcinoma expressed COX-2 more frequently than follicular adenoma (93.4% vs 21.1%) (p0.001). A higher percentage of cases of papillary microcarcinomas up-regulated COX-2 in comparison with all papillary carcinomas (p0.05). However, we could not establish any relationships among COX-2, patients ages or lymph node metastases in papillary carcinomas. COX-2 expression was found in 12 (92.3%) poorly differentiated carcinomas and in 13 (92.8%) undifferentiated carcinomas. We found that COX-2 is not always useful as a marker of malignancy. Our results suggest that COX-2 plays a role in progression of all thyroid carcinomas, but in papillary carcinomas, seems more important only in the early stages. COX-2 expression in the undifferentiated carcinoma deserves special consideration due to its prognosis and to the fact that selective COX-2 inhibitors were found to enhance tumour response to radiation in some studies.     

Regular immunohistochemical localization of endothelin-1 and endothelin-B receptor in normal, hyperplastic and neoplastic human adrenocortical cells

The locallzation of endothelin (ET)-l/blg ET-1, ET-3/big ET-3, ET-A and ET-B receptor was Immunohistochemlcally examined in human adrenal glands composed of 36 normal cases, nine hyperplasla, 70 adenomas and seven carcinomas of cortical cells. In normal adrenals, ET-1/blg ET-1 and ET-B receptor were regularly detected In the cortical cells, especially in the zona fasciculata for ET-1 and zone glomerulosa for ET-B receptor but not in the medulla, while ET-A receptor localized occasionally in endothelial cells or rarely in cortical cells and ET-3/blg ET-3 was very limited In the cortical cells. In hyperplasia, adenoma and carcinoma, ET-1 /big ET-1 and ET-B receptor showed frequent localization, although focal distrlbutlon of the ET-B receptor was rather predominant in these groups. ET-A receptor and ET-3/big ET-3 were very Infrequently expressed. Functioning versus non-functioning and hypertensive versus normotenshe cases revealed no significant differences in the frequency of posltive cells for ET-l /big ET-1, ET-3/big ET-3, ET-A receptor or ET-B receptor. Alternatively, the frequency of lmmunoreactivtty to ET-1/big ET-1 or ET-B receptor significantly decreased in hyperplasia, adenoma and carcinoma, when compared wlth that of normal adrenal cortex.
The present study, therefore, indicates that ET-1 /big ET-1 and ET-B receptor are a prevalent Iigand-receptor system In normal and hyperplastic/neoplastic adrenocortical cells, even wkh a malignant prdle, and may contribute in maintalnlng adrenocortical cell function or cell viability but not cell growth or systemic hypertension.     

Significance of hormone receptor status and tumor vessels in normal, hyperplastic and neoplastic endometrium

The aims of this study were to identity the roles of tumor vessels and hormone receptor status in normal, hyperplastic, and neoplastic endometrium, and to explore their relationships with other prognostic factors of endometrial adenocarcinoma. Endometrial curettage specimens of proliferative phase and secretory phase endometrium, simple hyperplasia with or without atypia, complex hyperplasia with or without atypia, and grade 1 adenocarcinoma were examined for estrogen receptor alpha (ER alpha), progesterone receptor (PgR), Ki-67 labeling index (LI), cyclin D1, microvessel density (MVD), and area of venules (AV) using an immunoperoxidase method. The results showed high levels of ER alpha in complex hyperplasia, and high levels of PgR in simple hyperplasia without atypia. Expression of ER alpha in the endometrium decreased in a stepwise manner from complex hyperplasia without atypia to grade 1 adenocarcinoma. Expression of PgR in the endometrium decreased in a stepwise manner from simple hyperplasia without atypia to grade 1 adenocarcinoma. In contrast, the expressions of Ki-67 LI, cyclin D1, MVD and AV in the endometrium increased in a stepwise manner from normal, simple or complex hyperplasia with or without atypia to grade 1 adenocarcinoma. These changes may become irreversible on progression from simple or complex hyperplasia to neoplasia.     

Proliferative activity of oxyphilic (Hurthle) cells in reactive and neoplastic thyroid lersions

The proliferative potential of oxyphilic (Hurthle) cells (HCs) present in neoplastic and non-neoplastic thyroid lesions is uncertain. To estimate the HCs ability to proliferate and to determine whether their proliferative activity correlates with the biologic behavior of different thyroid oxyphilic lesions, we selected 31 cases of chronic lymphocytic (Hashimoto’s) thyroiditis and 28 oxyphilic (Hurthle cell) thyroid tumors, including 12 adenomas and 16 carcinomas. Seven histologically normal thyroid specimens from euthyroid patients served as control tissue. The proliferative activity of HCs was evaluated by means of a double immunostaining for Ki67 and a mitochondrial antigen (which specifically recognizes oxyphilic cells). Oxyphilic cells in thyroiditis had a low proliferative activity (PA: 0.55%), although higher than that of normal thyroid parenchyma (PA: 0.06%). Neoplastic HC lesions had a mean proliferative activity of 1.56% and 6.26% in adenomas and carcinomas, respectively. A statistically significant difference was observed between proliferative activity of non-neoplastic and neoplastic lesions (p<0.01), but not within the tumor group, between adenomas and carcinomas. In addition, HC carcinomas had a statistically significant positive correlation between proliferative activity and tumor size (p<0.01) and the presence of necrosis (p<0.001).     

Angioimmunoblastic T-cell lymphoma with hyperplastic germinal centers: a clinicopathological and immunohistochemical study of 10 cases

An absence of germinal centers is one of the histological characteristics of angioimmunoblastic T-cell lymphoma (AITL). We report here 10 unusual cases of AITL with hyperplastic germinal centers. The clinical presentation of each patient was characterized by generalized lymphadenopathy, constitutional symptoms and polyclonal hypergammaglobulinemia. The initial biopsy findings of each patient were similar and were characterized by hyperplastic germinal centers with ill-defined borders and a proliferation of high endothelial venules (HEV). In the paracortical area there was a mixed infiltrate including irregularly shaped clusters or small nests of clear cells in all cases. Moreover, the clear cells invaded the lymphoid follicles, resulting in expansion of the germinal centers, except for one case. Immunohistochemistry revealed that the tumor cells, including clear cells, were CD4-expressing T cells. Some of the atypical lymphocytes were also Bcl-6-positive. A majority of the follicular dendritic cell networks showed a normal/reactive or an expanded/disrupted pattern in all cases. Moreover, three lesions possessed a few large irregularly shaped proliferations of follicular dendritic cells around the HEV Four cases progressed to AITL within a few years. The present 10 cases probably represent an early stage of AITL preceding follicular dendritic cell hyperplasia. Detection of clear cells, Bcl-6-positive atypical T lymphocytes, and foci of irregularly shaped proliferation of follicular dendritic cells appears to be critical for early diagnosis and treatment of AITL with hyperplastic follicles.