Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0149925 (small cell lung cancer)
 6,491 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The present case report describes the rare clinical presentation of diabetes insipidus in a patient with an ectopic ACTH syndrome (morning plasma cortisol 1.10 mumol/l, morning plasma ACTH 322 ng/l) due to disseminated small cell lung cancer including a metastasis in the posterior pituitary. The patient was treated by combination chemotherapy and at the same time received octreotide to control hypercortisolism and desmopressin (DDAVP) to control polyuria. Partial tumour remission was achieved resulting in decreased cortisol production and disappearance of the diabetes insipidus. Medical treatment could be discontinued. Several months later tumour regrowth occurred, with recurrence of hypercortisolism (mean morning plasma cortisol 0.74 mumol/l, mean morning plasma ACTH 112 ng/l) but without diabetes insipidus. Early treatment of hypercortisolism in patients with an ectopic ACTH syndrome and disseminated small cell lung cancer may prolong survival and improve the quality of life.
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PMID:Central diabetes insipidus and Cushing's syndrome due to ectopic ACTH production by disseminated small cell lung cancer: a case report. 971 40

We report on a case of rapid and marked hormone release as a result of rapid tumor reduction due to chemotherapy in a 36-year-old woman with ectopic ACTH syndrome due to small cell lung cancer. Treatment of the cancer with cisplatin and etoposide resulted in an 80% reduction in tumor size on computed tomographic scan within two weeks. Concurrently, plasma ACTH exhibited an unexpected and astonishing increase from 373 pg/ml before treatment to more than 1200 pg/ml. There were no biochemical characteristics observed in tumor lysis syndrome of solid tumors such as azotemia, increased LDH and hyperkalemia. The present case indicates that anticancer chemotherapy instituted in patients with ectopic ACTH syndrome could result in an acute increase of plasma ACTH and exacerbation of hypercortisolism, similar to tumor lysis syndrome, which is a potentially fatal complication following anti-cancer chemotherapy.
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PMID:Marked increase in plasma ACTH with tumor reduction after chemotherapy in ectopic ACTH syndrome. 1046 19

Ectopic secretion of ACTH, from sites such as small cell lung cancer (SCLC), results in severe Cushing's syndrome. ACTH is cleaved from POMC. The syndrome may occur when the highly tissue-specific promoter of the human POMC gene (POMC) is activated. The mechanism of activation is not fully understood. This promoter is embedded within a defined CpG island, and CpG islands are usually considered to be unmethylated in all tissues. We demonstrate that much of this CpG island is methylated in normal nonexpressing tissues, in contrast to somatically expressed CpG island promoters reported to date, and is specifically unmethylated in expressing tissues, tumors, and the POMC-expressing DMS-79 SCLC cell line. A narrow 100-bp region is free of methylation in all tissues. E2F factors binding to the upstream domain IV region of the promoter have been shown to be involved in the expression of POMC in SCLC. We show that these sites are methylated in normal nonexpressing tissues, which will prevent binding of E2F, but are unmethylated in expressing tissue. Methylation in vitro is sufficient for silencing of expression, which is not reversed by treatment with Trichostatin A, suggesting that inhibition of expression may be mediated by means other than recruitment of histone deacetylase activity. The DMS-79 cells lack POMC demethylating activity, implying that the methylation and expression patterns are likely to be set early or before neoplastic transformation, and that targeted de novo methylation might be a potential therapeutic strategy.
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PMID:The CpG island promoter of the human proopiomelanocortin gene is methylated in nonexpressing normal tissue and tumors and represses expression. 1115 38

ACTH-producing tumors of nonpituitary origin characteristically exhibit insensitivity to the negative feedback effects of glucocorticoids. In the DMS-79 cell line derived from an ACTH-producing small cell lung cancer we have previously identified an aberrantly spliced glucocorticoid receptor (GRDelta) that lacks a ligand-binding domain. We examined the interactions of this truncated form of GR with the proximal human proopiomelanocortin (POMC) promoter. In electrophoretic mobility shift assays GRDelta bound to the negative glucocorticoid response element (nGRE) at position -78 to -50 in the human POMC promoter. Nur77, an orphan nuclear receptor that exerts positive regulatory effects on the POMC gene is also known to bind to this DNA element. The functional properties of GR and GRDelta binding to this DNA element were examined in transient transfection experiments in murine AtT-20 corticotroph tumor cells. Reporter gene expression under the control of proximal POMC promoter elements was stimulated by addition of forskolin to the culture medium or by transfection with expression constructs for human Nak1, the human homologue of Nur77. Treatment of transfected cells with dexamethasone resulted in suppression of forskolin- or Nak1-stimulated POMC-reporter gene expression in the presence of co-transfected GR but not with GRDelta. The experiments indicate that in the human POMC promoter GRDelta is capable of binding to the nGRE but cannot effect trans-repression of POMC-reporter gene expression.
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PMID:Function of a truncated glucocorticoid receptor form at a negative glucocorticoid response element in the proopiomelanocortin gene. 1117 53

DNA microarray techniques were used to compare gene expression in an adrenocorticotropin (ACTH)-producing human small cell lung carcinoma line (DMS-79) with six other small cell lung cancer (SCLC) lines that do not produce ACTH. Twelve genes were expressed at more than five-fold higher levels in DMS-79 cells. Two transcription factors were the genes that exhibited the most remarkable over-expression: T-box 3 mRNA was detected at levels 19.37 +/- 3.78 times those observed in the SCLCs. Thyroid transcription factor (TTF-1, T/ebp, Nkx2.1) was expressed at 14.24 +/- 3.41-fold higher in DMS-79 cells. Seven genes were identified whose expression levels were at least five-fold lower in the ACTH-producing cell line. Variation in culture medium formulation did not significantly affect the gene expression profile of DMS-79 cells and expression data observed in microarray experiments were corroborated by northern blot analysis of RNA from the same cell lines. These experiments reveal new candidate genes that could be involved in the dysregulation of POMC gene expression manifested by ACTH-producing nonpituitary tumors.
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PMID:Gene expression phenotyping of an ACTH-producing small cell lung cancer line. 1514 32

The clinical usefulness of a new 99mTc-labeled somatostatin analogue has been studied from the standpoint of oncological diagnostics. The group of patients studied included 40 individuals with diagnosed malignant neoplasms (32 primary and 8 metastatic). Among the primary tumors were 7 pituitary adenomas (5 hormonally active and 2 inactive), 1 liposarcoma, 2 carcinoids, 1 breast carcinoma, and 21 cases of lung cancer (2 small cell and 19 non-small cell) were represented. The metastatic tumors consisted of: 3 malignant melanomas, 1 pheochromocytoma, 1 prostatic cancer, 1 leiomyosarcoma, 1 pancreatic carcinoma ectopically secreting ACTH, and 1 carcinoid of the thymus. The radiopharmaceutical, 99mTc-EDDA/HYNIC-octreotide, was i.v. administered at the activity of 740-925 MBq. The imaging was comprized of a whole-body scan and single photon emission computed tomography. Positive scintigrams were obtained in 4 of 5 hormonally active pituitary adenomas, in 1 of 2 cases of carcinoid, in liposarcoma, breast cancer, and all cases of small cell (SCLC) and non-small cell lung cancer (NSCLC). The neoplastic metastases were visualized in 2 of 3 cases of melanoma and in patients with pheochromocytoma, pancreatic carcinoma secreting ACTH, and thymic carcinoid. Scintigrams were negative in both hormonally inactive pituitary adenomas, in one case of metastatic malignant melanoma, leiomyosarcoma, and in cases of metastasis from the prostatic carcinomas. The results of this pilot study indicated that 99mTc-EDDA/HYNIC-TOC is a potentially useful radiopharmaceutical for the imaging of a wide range of primary and metastatic tumors. More detailed indications for the clinical usefulness of the new tracer for the imaging of selected tumor types require studies on much larger groups of patients. Special attention should be paid to the successful imaging of all cases of NSCLC.
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PMID:Clinical usefulness of 99mTc-EDDA/HYNIC-TOC scintigraphy in oncological diagnostics: a pilot study. 1518 7

Ectopic ACTH syndrome is a rare differential diagnosis of hypokalemic hypertension. Patients with ectopic ACTH syndrome due to small cell lung cancer have a poor prognosis. We report on a 68-year-old female patient who presented with dyspnea and hypokalemic hypertension. Endocrine testing was consistent with ectopic ACTH syndrome due to small cell lung cancer. After initiation of chemotherapy with etoposide and carboplatin ACTH and cortisol levels normalized and clinical symptoms impressively improved.
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PMID:[68-year-old female patient with dyspnea and hypokalemic hypertension]. 1848 Oct 38

When a 45-year-old man visited his local hospital with a complaint of chest discomfort and coughing, an abnormal chest X-ray shadow was found. On referral to our department, pigmentation was mainly observed on his face, however, no striae cutis distensae or facial swelling was observed. After a systemic examination, Stage IV small cell lung cancer with Cushing's syndrome was diagnosed. Marked increases in ACTH levels were observed, but no abnormality was found in the pituitary MRI findings, and therefore ACTH-producing small cell lung cancer was suspected. Chemotherapy was administered in addition to appropriate treatment for Cushing's syndrome. The tumor temporarily began to decrease in size, but hypercortisolemia remained, and thus adrenal hormone synthesis-inhibiting therapy was concurrently administered. Subsequently, cortisole began to decrease, but it could not be sufficiently controlled, resulting in occasional colonization by bacteria. Hypercortisolemia is believed to induce the suppression of the immune system, thereby affecting the outcome and QOL more than the immediate symptoms of cancer. Therefore, from an early stage, it is believed that adrenal cortical hormone synthesis-inhibiting therapy should be performed concurrently with chemotherapy, if hypercortisolemia cannot be controlled by radiation and chemotherapy alone.
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PMID:[A case of small cell lung cancer complicated by Cushing syndrome]. 1840 68

Dopamine agonists (DA) and somatostatin (SS) analogues have been proposed in the treatment of ACTH-producing neuro-endocrine tumours that cause Cushing's syndrome. Inversely, glucocorticoids (GCs) can differentially influence DA receptor D(2) or SS receptor subtype (sst) expression in rodent models. If this also occurs in human neuro-endocrine cells, then cortisol-lowering therapy could directly affect the expression of these target receptors. In this study, we investigated the effects of the GC dexamethasone (DEX) on D(2) and sst expression in three human neuro-endocrine cell lines: BON (carcinoid) and TT (medullary thyroid carcinoma) versus DMS (small cell lung cancer), which is severely GC resistant. In BON and TT, sst(2) mRNA was strongly down-regulated in a dose-dependent manner (IC(50) 0.84 nM and 0.16 nM), whereas sst(5) and especially D(2) were much more resistant to DEX treatment. Sst(2) down-regulation was abrogated by a GC receptor antagonist and reversible in time upon GC withdrawal. At the protein level, DEX also induced a decrease in the total number of SS (-52%) and sst(2)-specific (-42%) binding sites. Pretreatment with DEX abrogated calcitonin inhibition by sst(2)-preferring analogue octreotide in TT. In DMS, DEX did not cause significant changes in the expression of these receptor subtypes. In conclusion, we show that GCs selectively down-regulate sst(2), but not D(2) and only to a minor degree sst(5) in human neuro-endocrine BON and TT cells. This mechanism may also be responsible for the low expression of sst(2) in corticotroph adenomas and underwrite the current interest in sst(5) and D(2) as possible therapeutic targets for a medical treatment of Cushing's disease.
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PMID:Differential regulation of human dopamine D2 and somatostatin receptor subtype expression by glucocorticoids in vitro. 1885 17

Ectopic ACTH syndrome is a rare cause of Cushing's syndrome accounting for about 15% of all cases. Small cell lung cancer and bronchial carcinoids account for about half of the cases. Malignant neoplasm has rapid and more aggressive metabolic effects. We report a 54-year-old male patient with phenotypic features of Cushing's syndrome with severe hypokalemia, metabolic alkalosis, hypertension and altered mental status as manifestations of an ACTH-secreting small cell carcinoma from the lung. Ectopic ACTH syndrome should be highly considered in patients with hypertension and severe hypokalemic metabolic alkalosis, especially when a lung mass is discovered.
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PMID:Severe hypokalemia, metabolic alkalosis and hypertension in a 54 year old male with ectopic ACTH syndrome: a case report. 1982 70


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