Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027627 (metastases)
103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Our previous studies conducted in pancreatic cancer models established in nude mice and hamsters revealed that cloned somatostatin receptor subtype 2 (sst2) gene expression induced both antioncogenic and local antitumor bystander effects in vivo. In the present study, in vivo gene transfer of sst2 was investigated in two transplantable models of primary and metastatic pancreatic carcinoma developed in hamsters. LacZ reporter or mouse sst2 genes were expressed by means of two different delivery agents: an adenoviral vector and a synthetic polycationic carrier [linear polyethylenimine (PEI)]. sst2 was injected into either exponentially growing pancreatic primary tumors or hepatic metastases, and then transgene expression and tumor progression were investigated 5-6 days after gene transfer. Molecular mechanisms involved in the inhibition of tumor growth were also analyzed. Both adenovirus- and PEI-mediated in vivo gene transfer in primary pancreatic tumors induced an increase of beta-galactosidase activity and expression of sst2 transgene nRNA (100% and 86% of tumors for adenovirus and PEI vector, respectively). Adenoviral vector-based sst2 gene transfer resulted in significant reduction of pancreatic tumor growth (P < 0.05). Using PEI vector, both pancreatic primary tumor growth and metastatic tumor growth were also significantly slackened as compared with both LacZ-treated and untreated control groups (P < 0.02). Moreover, the proliferative index decreased significantly (P < 0.005), whereas apoptosis increased (P < 0.005) in tumors transferred with sst2 gene. The increase of apoptosis correlated with an activation of the caspase-3 and poly(ADP-ribose) polymerase pathways. We concluded that in both primary and metastatic pancreatic cancer models, the synthetic gene delivery system can achieve in vivo sst2 gene transfer and results in a significant antitumor effect characterized by an increase of apoptosis and an inhibition of cell proliferation. This new strategy of gene therapy allows the restoration of expression of an antioncogenic molecule and could be promising for the treatment of advanced pancreatic cancer.
...
PMID:Antitumor effect of in vivo somatostatin receptor subtype 2 gene transfer in primary and metastatic pancreatic cancer models. 1241 37

Somatostatin analogs are well established in the treatment of malignant endocrine pancreatic tumors (EPTs). Our goal is to individualize their treatment using receptor-subtype-specific analogs and, therefore, exploring the receptor expression is highly important. We have examined the expression of somatostatin receptor (sst) subtypes 1-5 on tumor cells and in intratumoral vessels in 28 tumor tissues from malignant EPTs with immunohistochemistry using sst-subtype-specific polyclonal antibodies. We found that sst(2) and sst(4) stained positive in 90% and sst(1) in 70% of the tumor tissues, whereas sst(3) and sst(5) stained positive in only 50% of the tumor tissues. Sst expression in intratumoral vessels was high for sst(2) and sst(4) (80%), moderate for sst(1) (40%), and low for sst(3) and sst(5) (10%). The ssts were evenly distributed among the different tumor subtypes. However, tumors belonging to the same subgroup of EPTs showed a variable expression of receptor subtypes. No differences in receptor-subtype expression could be seen between poorly and welldifferentiated tumors, nor between primary tumors and metastases. Prior medical treatment did not influence sst expression pattern. In conclusion, sst(2) and sst(4) were expressed in most tumor tissues and intratumoral vessels from EPTs. However, sst(3) and sst(5) were lacking in half of the tumor tissues and in most of the intratumoral vessels. These differences indicate the importance of determining each tumor s subset of receptors before treatment with receptor-subtype-specific analogs is initiated. The importance of sst expression in intratumoral vessels is not yet known.
...
PMID:Expression of somatostatin receptor subtypes 1 to 5 in tumor tissue and intratumoral vessels in malignant endocrine pancreatic tumors. 1266 86

Long-acting octapeptide somatostatin analogs can effectively control symptoms resulting from excessive hormone release in patients with endocrine tumors of the gastrointestinal tract, provided that these tumors and metastases show a high expression of the somatostatin receptor subtype 2. The presence of this receptor subtype on these tumors can be demonstrated by in vitro studies, but also in vivo using 111In-pentetreotide scintigraphy. In a few studies, significant antiproliferative effects of these drugs on these tumors have also been demonstrated. The effectiveness of octapeptide somatostatin analogs in the management of chemotherapy- related and AIDS-related diarrhea and in reducing postoperative complications of pancreatic surgery have also been demonstrated. These drugs have been used to decrease the output of enterocutaneous pancreatic fistulas and are prophylactically used to prevent the development of these fistulas. Octapeptide somatostatin analog therapy is widely accepted for the initial management of acute variceal bleeding in cirrhotic patients. These drugs are currently also being evaluated for the treatment of advanced hepatocellular carcinoma and malignant intestinal obstruction. Radiotherapy with octapeptide somatostatin analogs coupled to radionuclides such as indium-111, yttrium-90, and lutetium- 177 is currently being studied in phase I-III trials.
...
PMID:Somatostatin analog therapy in treatment of gastrointestinal disorders and tumors. 1272 9

We report a 21-year-old woman with ectopic ACTH syndrome due to islet cell carcinoma with multiple liver metastases. On admission, she showed Cushingoid appearance (moon face, central obesity etc.) and had acute respiratory distress syndrome due to pneumocystis carinii pneumonia. Laboratory examination revealed marked elevations of plasma ACTH (735 pg/ml) and cortisol (145 microg/dl) with a profound hypokalemia (2.0 mEq/l). She was found to have multiple masses in the liver and a solid mass in the tail of pancreas by abdominal computerized tomography scanning. Treatment with octreotide successfully reduced elevated plasma ACTH and cortisol levels, and she received frequent transhepatic arterial embolization and chemotherapy. The primary pancreatic tumor was surgically removed, revealing islet cell carcinoma which contained high content of ACTH (100 microg/g wet weight) and abundantly expressed proopiomelanocortin and somatostatin receptor subtype-2 mRNAs as determined by Northern blot analysis. Postoperatively, she was free from symptoms for almost one year. However, progressive enlargement of multiple liver metastases refractory to chemotherapy led her to decide on total hepatectomy and liver transplantation from her father. After liver transplantation, she remained almost free from symptoms for almost one year. However, metastases developed to the mediastinal and paraaortic lymph nodes as detected by 111[In] pentetreotide scintigraphy. Eleven months after liver transplantation, she was again treated with octreotide and, 16 months after, with metyrapone, both of which were effective in reducing ACTH and cortisol levels, respectively, until she died of acute respiratory failure. This case of a young female patient with ectopic ACTH-producing islet cell carcinoma of the pancreas was quite unique in that she survived for 5 years despite the acute onset and rapid progression of the multiple liver metastases at least in part due to the long-lasting favorable response to octreotide and living-related liver transplantation.
...
PMID:Octreotide-sensitive ectopic ACTH production by islet cell carcinoma with multiple liver metastases. 1280 33

To investigate somatostatin receptor scintigraphy (SRS) usefulness compared to conventional imaging procedures (CIP) in non-functioning gastroenteropatic (GEP) neuroendocrine tumors, we studied 40 patients, 30 in follow-up (FU) after previous operation for primary tumor (27 cases) or non-operable for disseminated metastases (3 cases), and 10 in the phase of initial diagnosis and staging (IDS). All patients were asymptomatic for hormone overexpression, with slightly high serum chromogranine A in 6 FU. The definitive diagnosis was obtained by surgery, laparotomy or percutaneous CT/US guided biopsy. Within 1 month before scintigraphy, all patients had undergone at least 2 of 3 CIP (CT, MRI and US); 4 and 24 h after 250 MBq 111In-pentetreotide i.v. injection, whole body scanning, planar and SPECT over the abdomen or other suspect regions were performed. Globally, 135 neoplastic lesions (84 hepatic, 34 abdominal extra-hepatic and 17 extra-abdominal) were ascertained in 32/40 patients; SPECT was positive in 29 cases, CIP in 28 and planar in 20, while all 3 procedures were true negative in the remaining 8 cases. Per patient sensitivity and accuracy were significantly higher at SPECT and CIP than planar. SPECT showed a significantly higher per lesion sensitivity (89.6%) than CIP (72.6%) and planar (53.3%) while CIP sensitivity was significantly higher than planar. SPECT correctly modified CIP patient classification and thus management in 18.7% of patients, while it downstaged the disease in 9.4% in respect of CIP; planar was incorrect in 51.3% of cases. SPECT and CIP combined use achieved 100% accuracy and correctly classified all patients. 111In-pentetreotide SRS, particularly SPECT, is a useful diagnostic tool in the detection of non-functioning GEP tumors, contributing to correct patient classification and appropriate therapeutic strategy. SPECT proved more sensitive than CIP, but their combined use achieved the highest accuracy values and gave the most accurate disease staging.
...
PMID:Somatostatin receptor scintigraphy with 111In-pentetreotide in non-functioning gastroenteropancreatic neuroendocrine tumors. 1461 42

Medullary thyroid carcinoma (MTC) is a rare thyroid malignancy, which is familial in 25-29% of cases. Familial MTC is due to germ-line mutations in the RET proto-oncogene. It can occur either alone or as the thyroid manifestation of MEN 2 syndromes; the disease is inherited in an autosomal dominant fashion with age-related penetrance. The treatment of choice is surgery. Early diagnosis and an adeguate initial operation provide the best chance of cure. Hence, the diagnosis should be made preoperatively. Genetic testing can identify almost all affected individuals with hereditary disease and permits prophylactic/early thyroidectomy in gene carriers. Total thyroidectomy and lymphadenectomy of the cervicocentral compartment is mandatory in all patients. In addition, bilateral dissection of the cervicolateral compartment should be done in all cases with more than microscopic disease. Plasma calcitonin is an excellent marker for postoperative follow-up. Treatment of persistent/recurrent disease is primarily surgical. Hence, a reoperative cervical lymphadenectomy should be considered in patients with persistently elevated calcitonin levels and no signs of distant metastases. Chemotherapy and external radiotherapy have little impact on the course of avanced disease; more promising is metabolic radiotherapy with Y90-DOTATOC in patients with somatostatin receptor-positive tumours.
...
PMID:[Treatment of familial medullary thyroid carcinoma]. 1466 8

The rationale underlying an aggressive approach in the management of some carcinoid patients is explained and illustrated by the presented case of a middle-aged man with advanced classic typical midgut carcinoid. The patient exhibited somatostatin receptor scintigraphy-positive massive liver metastases, carcinoid syndrome, severe tricuspid and pulmonic cardiac valve disease with congestive heart failure, ascites and malnutrition. He had been treated for several years with supportive medications and biotherapy including octreotide and alpha interferon but his tumor eventually progressed and his overall condition was markedly deteriorated when he first sought more aggressive treatment. This consisted of prompt replacement of both tricuspid and pulmonic valves, followed by hepatic artery chemoembolus (HACE) injection and then surgical tumor debulking including excision of the primary tumor in the small intestine. In addition, radiofrequency ablation was utilized to reduce the volume of metastases in the liver. Prophylactic cholecystectomy was also performed and a biopsy of tumor was submitted for cell culture drug resistance testing. This was followed by systemic chemotherapy utilizing the drug (docetaxel) which the in vitro studies suggested as most likely to be effective. His excellent response to this succession of treatments exemplifies the successful application of aggressive sequential multi-modality therapy.
...
PMID:Carcinoid case presentation and discussion: the American perspective. 1471 63

Somatostatin receptors are widely expressed on cells and tissues throughout the human body. Apart from their expression in the physiological target organs of the peptide, somatostatin receptors are also expressed in various tumours. The expression of somatostatin receptors on neuroendocrine tumours led to the development of somatostatin receptor scintigraphy using [(111)In-DTPA-D-Phe(1)]-octreotide ((111)In-pentetreotide) in order to visualize somatostatin receptor positive tumours and their metastases in vivo. Previous studies reported the expression of somatostatin receptors in both normal and pathological cells and tissues of the human immune system as well. Somatostatin receptors have been demonstrated in Hodgkin's and non-Hodgkin's lymphomas and sst scintigraphy has shown to be a useful tool in diagnosis and staging of these diseases. Moreover, sst expression has also been detected in granulomateus diseases, like sarcoidosis and auto-immune diseases, like rheumatoid arthritis. In this paper we discuss the (possible) role of somatostatin receptor scintigraphy in diagnosis, staging or follow-up of patients suffering from sarcoidosis and rheumatoid arthritis.
...
PMID:The role of octreotide scintigraphy in rheumatoid arthritis and sarcoidosis. 1497 19

99mTc-Depreotide has been used on single pulmonary nodules to identify somatostatin receptor-positive lung cancer. We report that pulmonary metastases of a 78-y-old man with postradical nephrectomy for renal cell carcinoma were detected by (99m)Tc-depreotide chest SPECT. Thus, (99m)Tc-depreotide chest SPECT can be used to diagnose secondary lung cancer, such as pulmonary metastases from renal cell carcinoma with somatostatin receptor-positive tumor, other than primary lung cancer. Depending on whether the (99m)Tc-depreotide was positive for pulmonary metastases, the patient underwent an appropriate therapy without further invasive procedures.
...
PMID:99mTc-Depreotide chest SPECT demonstrates pulmonary metastases from renal cell carcinoma. 1499 Jun 70

The aim of this study was to assess the feasibility of somatostatin receptor scintigraphy (SRS) for the detection of the site of unknown primary neuroendocrine neoplasms in patients in whom clinical examination and conventional radiological imaging had failed to do so. From 1996 to 2000, 36 patients were referred with gastro-entero-pancreatic (GEP) neuroendocrine tumours. In these patients, no clinical, radiological or endoscopic diagnostic modalities had been able to identify the primary tumour. Twenty-nine patients had liver metastases. Of the others, one had skin and one had lymph node metastases, three had diffuse metastatic involvement and two had carcinoid syndrome. SRS was carried out with both whole-body and single-photon emission tomography (SPET) acquisition, 24 and 48 h after the intravenous administration of In-pentetreotide. SRS findings were suggestive of the possible site of the primary lesion in 14 patients (39%). Six patients underwent surgery on the basis of the SRS findings and, therefore, the final, i.e. pathological, diagnosis was reached. In two patients, the final diagnosis was obtained within 6 months of SRS by means of a follow-up computed tomography (CT) scan. In the remaining six patients, the final diagnosis was reached after at least 2 years of follow-up by means of clinical, radiological and/or nuclear medicine findings. In all eight patients, the primary site identified during follow-up was consistent with the SRS findings. It can be concluded that SRS modified management in the six patients who had surgery. However, the most important finding was that SRS prompted surgical management in 17% of cases.
...
PMID:Feasibility of somatostatin receptor scintigraphy in the detection of occult primary gastro-entero-pancreatic (GEP) neuroendocrine tumours. 1510 May 2


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>