Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01350 (gastrin)
 9,683 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The recent cloning of a second estrogen receptor (ER) provided a new tool to investigate and clarify how estrogens are capable of communicating with the brain and influence gene expression and neural function. The purpose of the present study was to define the neuroanatomical organization of each receptor subtype using a side-by-side approach and to characterize the cellular population (s) expressing the ERbeta transcript in the endocrine hypothalamus using immunohistochemistry combined with in situ hybridization. Axonal transport inhibition was accomplished to cause neuropeptide accumulation into the cytoplasm and thus facilitate the detection of all positive luteinizing hormone-releasing hormone (LHRH), corticotropin-releasing factor (CRF), vasopressin (AVP), oxytocin (OT), gastrin-related peptide (GRP), and enkephalin (ENK) neurons. The genes encoding either ERalpha or -beta were expressed in numerous limbic-associated structures, and fine differences were found in terms of intensity and positive signal. Such phenomenon is best represented by the bed nucleus of the stria terminalis (BnST) and preoptic area/anterior hypothalamus, where the expression pattern of both transcripts differed across subnuclei. The novel ER was also found to be expressed quite exclusively in other hypothalamic nuclei, including the supraoptic (SON) and selective compartments (magnocellular and autonomic divisions) of the paraventricular nucleus (PVN). A high percentage of the ERbeta-expressing neurons located in the ventro- and dorsomedial PVN are of OT type; 40% of the OT-ir cells forming the medial magnocellular and ventromedial parvocellular PVN showed a clear hybridization signal for ERbeta mRNA, whereas a lower percentage (15-20%) of OT neurons were positive in the caudal parvocellular PVN and no double-labeled cells were found in the rostral PVN and other regions of the brain with the exception of the SON. Very few AVP-ir neurons expressing ERbeta transcript were found throughout the rat brain, although the medial PVN displayed some scattered double-labeled cells (<5%). Quite interestingly, the large majority of the ERbeta-positive cells in the caudal PVN were colocalized within CRF-ir perikarya. Indeed, more than 60-80% of the CRF-containing cells located in the caudolateral division of the parvocellular PVN exhibited a positive hybridization signal for ERbeta mRNA, whereas very few (<5%) neuroendocrine CRF-ir parvocellular neurons of the medial PVN expressed the gene encoding ERbeta. A small percentage of ERbeta-expressing cells in the dorsocaudal and ventromedial zones of the parvocellular PVN were also ENK positive. The ventral zone of the medial parvocellular PVN also displayed GRP-ir neurons, but no convincing hybridization signal for ERbeta was detected in this neuronal population. Finally, as previously described for the gene encoding the classic ER, LHRH neurons of both intact and colchicine-pretreated animals did not express the novel estrogen receptor. This study shows a differential pattern of expression of both receptors in the brain of intact rats and that ERbeta is expressed at various levels in distinct neuropeptidergic populations, including OT, CRF, and ENK. The influence of estrogen in mediating genomic and neuronal responses may therefore take place within these specific cellular groups in the brains of cycling as well as intact male mammals.
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PMID:Expression and neuropeptidergic characterization of estrogen receptors (ERalpha and ERbeta) throughout the rat brain: anatomical evidence of distinct roles of each subtype. 973 72

We report a case of metastatic gastrinoma to the breast morphologically mimicking solid papillary carcinoma of the breast. A 59-year-old woman presented with a hypoechoic right breast mass that histologically revealed solid nests of small monotonous tumor cells, fibrovascular cores, and round to oval nuclei with fine chromatin and small nucleoli. Immunohistochemistry demonstrated chromogranin and synaptophysin positivity. Tumor prognostic markers showed weak positivity for estrogen receptor and negativity for progesterone receptor. Although an initial diagnosis of solid papillary carcinoma was rendered, subsequent identification of the patient's clinical history of pancreatic gastrinoma and an additional immunohistochemical stain for gastrin supported a diagnosis of metastatic gastrinoma. We report this rare case to increase awareness of metastatic neuroendocrine tumors in the breast. Multiple breast lesions and lack of expression of estrogen/progesterone hormone receptors should prompt careful review of the patient's clinical history to rule out metastatic neuroendocrine disease.
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PMID:Metastatic gastrinoma in the breast mimicking primary solid papillary carcinoma. 2734 8

The Gastrin-Releasing Peptide Receptor (GRPR) is over-expressed in estrogen receptor (ER) positive breast tumors and related metastatic lymph nodes offering the opportunity of imaging and therapy of luminal tumors. 68Ga-RM2 binding and 18F-FDG binding in tumoral zones were measured and compared using tissue micro-imaging with a beta imager on 14 breast cancer samples (10 primaries and 4 associated metastatic lymph nodes). Results were then assessed against ER expression, progesterone receptor (PR) expression, HER2 over-expression or not and Ki-67 expression. GRPR immunohistochemistry (IHC) was also performed on all samples. We also retrospectively compared 68Ga-RM2 and 18F-FDG bindings to 18F-FDG SUVmax on the pre-therapeutic PET/CT examination, if available. 68Ga-RM2 binding was significantly higher in tumors expressing GRPR on IHC than in GRPR-negative tumors (P = 0.022). In ER+ tumors, binding of 68Ga-RM2 was significantly higher than 18F-FDG (P = 0.015). In tumors with low Ki-67, 68Ga-RM2 binding was also significantly increased compared to 18F-FDG (P = 0.029). Overall, the binding of 68Ga-RM2 and 18F-FDG displayed an opposite pattern in tumor samples and 68Ga-RM2 binding was significantly higher in tumors that had low 18F-FDG binding (P = 0.021). This inverse correlation was also documented in the few patients in whom a 18F-FDG PET/CT examination before surgery was available. Findings from this in vitro study suggest that GRPR targeting can be an alternative to 18F-FDG imaging in ER+ breast tumors. Moreover, because GRPR antagonists can also be labeled with lutetium-177 this opens new avenues for targeted radionuclide therapy in the subset of patients with progressive metastatic disease following conventional treatments.
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PMID:Comparison of the binding of the gastrin-releasing peptide receptor (GRP-R) antagonist 68Ga-RM2 and 18F-FDG in breast cancer samples. 3064 33