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

Attempts to improve human tumor detection by non-radioactive magnetic resonance techniques have led several investigators to develop antibody-linked paramagnetic contrast agents. Initial studies focused on gadolinium conjugated to monoclonal antibodies. However, very high levels of this contrast agent were needed to significantly reduce proton relaxation times and obtain improved MR images. The use of magnetite (Fe 3O 4) as an MR contrast agent provides a magnetic moment that is approximately one order of magnitude larger than gadolinium. In this study monoclonal antibodies 44 x 14 (specific for squamous cell carcinoma) and 436G10 (specific for melanoma) were obtained from ammonium sulfate precipitation of tumor ascitic fluid. Equal volumes of magnetite solution (1.87 mg Fe/ml) and antibody solution 44 x 14 (5.24 mg protein/ml) and 436G10 (0.64 mg protein/ml) were mixed and sonicated. The 44 x 14-magnetite and 436G10-magnetite solutions were then added to equal volumes of M20 and P3 squamous cell carcinoma cell lines. T1 and T2 values were obtained on a Praxis II NMR spectrometer equipped with a 10 mm probe and 0.25 Tesla permanent magnet. The T2 relaxation times of the magnetite-antibody-cell mixtures were 31 ms with an R = 0.985 for both experimental samples. Our results demonstrate a significant decrease in T2 by binding of the magnetite-coated antibodies to these melanoma and carcinoma cells in vitro. The possibility of detecting subclinical local and metastatic disease with magnetite linked to monoclonal antibodies followed by MRI guided laser tumor ablation therapy may render this technique clinically attractive for treatment of deep-seated tumors.
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PMID:Monoclonal antibody-coated magnetite particles as contrast agents for MR imaging and laser therapy of human tumors. 1014 59

The purpose of this study was to evaluate the potential of superparamagnetic iron oxide particles (SPIO) as tissue specific contrast agent in magnetic resonance (MR) imaging in detection and characterization of focal hepatic lesions. We investigated 45 patients with focal hepatic lesions. T1-weighted SE (TR 650/TE 15 ms) and T2-weighted SE (TR 2015-2030/TE 45 and 90 ms) unenhanced images were obtained. After SPIO application we performed T1-weighted images with and T2-weighted images with and without fat suppression using the same image parameters. Liver signal intensity decreased by 74% (min 47%, max 83%) on T2-weighted images after application of the contrast agent. Benign lesions (FNH, adenoma) showed an average signal drop of 40% (min 20%, max 47%) whereas malignant lesions showed no significant change of signal intensity on post-contrast images. The mean tumor-to-liver contrast-to-noise ratio (C/N) was improved in all post-contrast sequences irrespective of the lesion type. An additional increase of tumor-to-liver contrast by use of fat suppression technique could be established in the slightly T2-weighted sequence (TE 45 ms). In metastases, divided in different size groups, we could determine a significant size relation of tumor-to-liver C/N. After SPIO application the number of detected lesions increased distinctly, especially small foci are more easily demonstrated. SPIO particles are a efficacious contrast agent for MR examinations of the liver. For tumor characterization T1- and T2-weighted pre- and post-contrast images are necessary. The T1-weighted sequences are helpful to differentiate benign lesions such as cysts and hemangiomas from malignant lesions. Detection and differential diagnoses of hepatic lesions are improved by use of the SPIO-particles.
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PMID:MRI with superparamagnetic iron oxide: efficacy in the detection and characterization of focal hepatic lesions. 1019 81

In order to determine the effects of the multifunctional iron-binding glycoprotein, lactoferrin (LF), and related compounds on tumor growth and metastasis, bovine LF (bLF), and bLF hydrolysate and lactoferricin (bLFcin), active products generated by acid-pepsin hydrolysis were administered orally to BALB/c mice bearing subcutaneous (s.c.) implants of the highly metastatic colon carcinoma 26 (Co 26Lu). bLF and the bLF hydrolysate demonstrated significant inhibition of lung metastatic colony formation from s.c. implanted tumors without appreciable effects on tumor growth. bLFcin displayed a tendency for inhibition of lung metastasis. On the other hand, bLF did not exert marked anti-metastatic activity in athymic nude mice bearing Co 26Lu, though bLF had a tendency to inhibit the lung metastatic colony formation associated with anti-asialoGM1 antibody (Ab) treatment. AsialoGM1+ and CD8+ cells in white blood cells were increased after treatment with bLF. In vitro, the viability of Co 26Lu-F55 cells was markedly decreased when co-cultured with white blood cells from mice administrated bLF p.o., but recovered on treatment with anti-asialoGM1 Ab or anti-CD8 mAb and complement. The results suggest bLF and related compounds might find application as tools in the control of metastasis and that asialoGM1+ and CD8+ cells in the blood are important for their inhibitory effects.
Clin Exp Metastasis 1999 Feb
PMID:Inhibitory effects of bovine lactoferrin on colon carcinoma 26 lung metastasis in mice. 1039 Jan 45

The purpose of this study was to evaluate the clinical efficacy of ultrasmall superparamagnetic iron oxide particles as a magnetic resonance (MR) contrast agent in differentiating metastatic from benign lymph nodes. Eighteen patients with primary lung malignancy and suspected regional lymph node metastases underwent MR imaging before and after Combidex(R) infusion in a multi-institutional study. All MR sequences were interpreted by one or more board-certified radiologists experienced in imaging thoracic malignancy. Each patient was evaluated for the number and location of lymph nodes, homogeneity of nodal signal, and possible change of MR signal post contrast. All patients underwent resection or sampling of the MR-identified lymph node(s) 1-35 day(s) post contrast MR imaging. In all, 27 lymph nodes or nodal groups were available for histopathologic correlation. Combidex had a sensitivity of 92% and a specificity of 80% in identifying pathologically confirmed metastatic mediastinal lymph nodes. Based on our preliminary data, Combidex MR imaging may provide additional functional information useful in the staging of mediastinal lymph nodes.
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PMID:Multicenter clinical trial of ultrasmall superparamagnetic iron oxide in the evaluation of mediastinal lymph nodes in patients with primary lung carcinoma. 1050 10

Mediastinal paragangliomas are rare neoplasms in children. Anemia, as a paraneoplastic syndrome, has been described in adults with metastatic paraganglioma. The management of paraneoplastic anemia from metastatic paraganglioma has been problematic, with no reports in the literature describing successful treatment. This article describes a 17-year-old Jehovah's Witness with a mediastinal paraganglioma, hepatic metastases, and severe anemia. The patient and his family refused blood products and the anemia was refractory to erythropoietin and elemental iron therapy. Serial chemoembolization of the hepatic lesions resulted in resolution of the anemia, allowing subsequent debulking of the mediastinal paraganglioma.
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PMID:Metastatic paraganglioma and paraneoplastic-induced anemia in an adolescent: treatment with hepatic arterial chemoembolization. 1059 70

The detection of nodal metastases is of utmost importance in oncologic imaging. Ultrasmall superparamagnetic iron oxide particles (USPIO) are novel contrast agents specifically developed for MR lymphography. After intravenous administration, they are taken up by the macrophages of the lymph nodes, where they accumulate. They reduce the signal intensity (SI) of normally functioning nodes on postcontrast T2-and T2*-weighted images through the magnetic susceptibility effects on iron oxide. Metastatic nodes, in which macrophages are replaced by tumor cells, show no significant change in SI on postcontrast T2-and T2*-weighted images. Early clinical experience suggests that USPIO-enhanced MR lymphography improves the sensitivity and specificity for the detection of nodal metastases. It also suggests that micrometastases could be detected in normal-sized nodes. This article reviews the physiochemical properties of USPIO contrast agents, their enhancement patterns, and early clinical experience.
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PMID:Iron oxide-enhanced MR lymphography: initial experience. 1092 66

Chromophobe renal cell carcinoma (RCC) is a newly established entity of renal neoplasm with histological and molecular biological features different from those of common RCCs. Chromophobe RCC shows characteristically cloudy and reticular cytoplasm and cellular features resembling distal nephron. Its prognosis has been reported to be more favorable than that of common RCCs. Recently, however, several cases have been reported which showed sarcomatoid change to present poor prognosis. Here we present a case of chromophobe RCC with sarcomatoid change which was once resected surgically. The surgically resected tumor was histologically composed of chromophobe epithelial cell sheets and sarcomatoid elements. The former showed positivity for colloid iron staining, and was immunohistochemically positive for E-cadherin and epithelial membrane antigen (EMA), whereas the latter was positive for vimentin instead of colloid iron and E-cadherin. EMA was focally positive in the sarcomatoid element. The patient died with systemic metastases 14 months after the operation. Histologically, the metastatic tumors were composed only of sarcomatoid element lacking epithelial element. Based on these findings and previous reports, this case supports the existence of a tumor progression pathway from chromophobe to sarcomatoid RCC. It is necessary to perform careful postoperative investigation of chromophobe RCC due to its possible histological progression to the sarcomatoid subtype.
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PMID:Chromophobe renal cell carcinoma with sarcomatoid change. A case report. 1099 40

Magnetic resonance imaging (MRI) relies on the physical properties of unpaired protons in tissues to generate images. Unpaired protons behave like tiny bar magnets and will align themselves in a magnetic field. Radiofrequency pulses will excite these aligned protons to higher energy states. As they return to their original state, they will release this energy as radio waves. The frequency of the radio waves depends on the local magnetic field and by varying this over a subject, it is possible to build the images we are familiar with. In general, MRI has not been sufficiently sensitive or specific in the assessment of diffuse liver disease for clinical use. However, because of the specific characteristics of fat and iron, it may be useful in the assessment of hepatic steatosis and iron overload. Magnetic resonance imaging is useful in the assessment of focal liver disease, particularly in conjunction with contrast agents. Haemangiomas have a characteristic bright appearance on T2 weighted images because of the slow flowing blood in dilated sinusoids. Focal nodular hyperplasia (FNH) has a homogenous appearance, and enhances early in the arterial phase after gadolinium injection, while the central scar typically enhances late. Hepatic adenomas have a more heterogenous appearance and also enhance in the arterial phase, but less briskly than FNH. Hepatocellular carcinoma is similar to an adenoma, but typically occurs in a cirrhotic liver and has earlier washout of contrast. The appearance of metastases depends on the underlying primary malignancy. Overall, MRI appears more sensitive and specific than computed tomography with contrast for the detection and evaluation of malignant lesions.
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PMID:Magnetic resonance imaging (MRI) and diseases of the liver and biliary tract. Part 1. Basic principles, MRI in the assessment of diffuse and focal hepatic disease. 1105 26

A variety of different categories of contrast agents, and within each category a number of individual agents, are currently available for clinical use in magnetic resonance (MR) imaging of the liver. In this review, the use of nonspecific extracellular gadolinium chelates, reticuloendothelial system-specific iron oxide particulate agents, hepatocyte-selective agents, and combined perfusion and hepatocyte-selective agents are described. Most clinical experience is with nonspecific extracellular gadolinium chelates. The relatively low cost, safety, good patient tolerance, and ability to help detect and characterize a wide range of liver diseases have rendered gadolinium chelates as commonly used agents. Reticuloendothelial system-specific agents improve lesion detection by decreasing the signal intensity of background liver on T2-weighted MR images, which increases the conspicuity of focal hepatic lesions with negligible reticuloendothelial cells (eg, metastases). Hepatocyte-selective agents increase the signal intensity of background liver on T1-weighted images, which increases the conspicuity of focal lesions that do not contain hepatocytes (eg, metastases). The clinical application of the different categories of contrast agents, techniques for their administration, sequences to be used, and appearances of common entities on contrast agent-enhanced studies are described.
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PMID:Contrast agents for MR imaging of the liver. 1115 76

It is well known that iron plays an essential role in many biochemical reactions and that rapidly growing cells require more iron for their growth and metabolism than resting cells. Transferrin and its receptor are required for entry of iron into the cell. In contrast, ferritin is a cellular storage protein whose main function is to sequester excess ferric iron and thus prevent high concentrations of soluble ferric iron from becoming toxic to the cell. However, the clinical significance of both transferrin receptor and ferritin mRNA levels have not previously been described in tumors from breast cancer patients. In this study, tumor tissue mRNA levels of transferrin receptor and ferritin were quantitated on forty-two breast cancer patients. A highly sensitive non-radioisotopic cDNA polymerase chain reaction assay was used to quantitate expression of mRNA. The expression of glyceraldehyde-3-phosphate dehydrogenase served as the control. In the tumor tissue from the 42 breast cancer patients the transferrin receptor mRNA levels were significantly correlated to the ferritin H-chain mRNA levels (Spearman correlation r = 0.5433, p = 0.0002; Pearson correlation r = 0.6276, p < 0.0001). The level of amplified transferrin receptor complementary DNA was related to differentiation (ANOVA, p = 0.042) with poorly differentiated tumors having high levels of transferrin receptor mRNA. Further, the levels of amplified gene for ferritin heavy chain complementary DNA was directly related to axillary lymph nodes status (Student's t-test, p = 0.044), presence of metastatic disease (Student's t-test, p = 0.046) and clinical stage (stage I + stage II versus stage III + stage IV; Student's t-test, p = 0.0181). These results demonstrate that non-radioisotopic RT-PCR is a very sensitive method for determining mRNA levels in tumor tissue. Additionally, the quantitation of expression of transferrin receptor and ferritin heavy chain mRNA may be useful for assessing prognosis and guiding therapeutic decisions in breast cancer patients.
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PMID:Expression of transferrin receptor and ferritin H-chain mRNA are associated with clinical and histopathological prognostic indicators in breast cancer. 1129 1


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