Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of nonspecific antitumoral immunity caused by BCG on intratesticular development of 256 Walker carcinosarcoma has been studied on male hyper- or hypothyroidectomized rats. Thyroid hormones level was altered by administration of T4. Alkiron or thyroidectomy. The time and route of BCG administration differed from one lot to another. Authors' results show that administration of BCG before or concomitantly with the graft stimulates tumor development, whereas administration of BCG mixed with a suspension of tumoral cells causes marked inhibition in the development of primary tumor and metastasis, an inhibition which is not influenced by the thyroid hormones level. In vitro proliferation of the tumoral cells as well as histopathologic examination of the tumors suggest the involvement of a complex process in achieving the nonspecific antitumoral immunity.
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PMID:Influence of BCG on the development of 256 Walker carcinosarcoma inoculated intratesticularly in the rat, in relation to thyroid status alerations. 743 63

Somatostatin (SRIF) immunoreactivity has been frequently reported in tumor tissues of cell types, belonging to the APUD system, including medullary thyroid carcinoma (MTC). However, the value of SRIF as a plasma tumor marker for MTC is controversial. We have measured SRIF plasma levels in 35 patients with different stages of MTC to evaluate the use of SRIF as a plasma tumor marker compared to the current "gold standard" calcitonin (CT). The median SRIF value in healthy controls was 36.5 pg/mL, the upper limit of normal was defined at the controls. The median value was 28 pg/mL (p = 0.37, Mann-Whitney U test). Five patients in the control group and three in the MTC group had SRIF levels that exceed the 95th percentile. SRIF and CT levels correlated only weakly (0.38), as determined by the Spearman rank order correlation test. Pentagastrin stimulation led to a diagnostic increase in SRIF levels in only one of five MTC patients. During selective venous catheterization, diagnostic gradients for CT, allowing tumor localization, could be demonstrated, whereas measurement of SRIF levels did not aid in tumor detection. Although SRIF immunostaining may be valuable as an additional marker in the histochemical diagnosis of MTC, SRIF has no value as a plasma tumor marker in the diagnosis of this disease.
Thyroid 1995 Aug
PMID:Evaluation of somatostatin as a plasma tumor marker in medullary thyroid carcinoma. 748 70

The in vitro synthesis and deposition of laminin family glycoproteins were studied using primary porcine thyroid cells cultured as monolayers or in follicles. The latter organization mimics the in vivo state of these polarized epithelial cells. In both cell systems a trimeric molecule was immunoprecipitated by using polyclonal antibodies against EHS-laminin. When the cells were fully polarized the protein was found at the basal pole of cells, irrespective of their organization. However, this molecule was different from laminin purified from a traditional source, the murine Engelbreth-Holm-Swarm (EHS) tumor. Thyroid cell laminin was composed of two light chains, analogous to EHS B1 and B2, and a disulfide-bonded heavy chain not found in EHS-laminin. The heavy chain was first synthesized as a 380 kDa polypeptide, then rapidly cleaved to a doublet of 350-380 kDa, which was subsequently found in both cell extracts and conditioned culture media. This thyroid laminin variant was compared with merosin, another variant found in the basement membranes of trophoblast, Schwann cells, striated muscle and liver. The heavy chain (M) of merosin shows homology to EHS-laminin heavy chain at the C-terminal domain, and is usually found as two polypeptides of 80 kDa and 300 kDa (Ehrig K., Leivo I., Argraves W. S., Ruoslahti E. and Engvall E. Proc. Nat. Acad. Sci. 87, 3264-3268, 1990). mRNA of the M chain was identified by RT-PCR in freshly isolated thyrocytes as well as in 6-day-old cultured thyroid cells. Furthermore, both the classical laminin heavy chain and the 350 kDa variant were detected by immunoblotting and immunofluorescence in the thyroid gland in vivo. All these results suggest strongly that merosin is a basement membrane component of thyroid cells in vivo and in vitro.
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PMID:Merosin is synthesized by thyroid cells in primary culture irrespective of cellular organization. 751 12

To examine changes in serum TSH and determine whether the sustained excess is necessary for the development and/or progression of thyroid tumors, male F344 rats were administered drinking water containing thiourea (TU), at 0.1 or 0.05%, or sulfadimethoxine (SM), at 0.025 or 0.0125%, for one week in Experiment I. All of the treated animals showed decreased serum levels of T3 and T4 and an increased TSH. In Experiment II, male rats were given a s.c. injection of N-bis(2-hydroxypropyl) nitrosamine (DHPN:1500 mg/kg BW) and, starting one week later, received drinking water containing the same doses of TU or SM as in Experiment I for the following 20 weeks. Thyroid follicular proliferative lesions were induced in most rats treated with TU and SM. However, these treated animals did not demonstrate any consistent alterations in serum T3, T4 and TSH levels, except for the high dose TU group. The present studies thus suggest that thyroid tumors can grow even under conditions of fluctuating serum TSH levels during the progression phase, although TSH stimulation might be an absolute requirement in the early phase of tumor development.
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PMID:Thyroid proliferative lesions induced by anti-thyroid drugs in rats are not always accompanied by sustained increases in serum TSH. 753 49

The expression of adhesion molecules in thyroid specimens from 10 cases of papillary adenocarcinoma, 5 cases of follicular adenoma and 3 normal thyroid specimens was examined by an immunohistochemical method. Thyroid epithelial cells from all cases of papillary adenocarcinoma expressed the intercellular adhesion molecule 1 (ICAM-1, CD54). The ICAM-1-positive staining in these was detected predominantly on the apical site of malignant thyroid epithelial cells. However, no ICAM-1 expression was detected on thyrocytes of adenoma, and normal thyroid tissues. Furthermore, thyroid epithelial cells in patients with thyroid tumor and normal thyroid tissue did not react with anti-LFA-1, anti-VLA-4, anti-VCAM-1 and anti-ELAM-1 monoclonal antibodies. It is speculated that ICAM-1 expression in thyroid papillary adenocarcinoma may have a functional significance.
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PMID:Expression of adhesion molecule ICAM-1 (CD54) in thyroid papillary adenocarcinoma. 753 57

Follicular thyroid carcinomas (FTC) characteristically spread via blood vessels, while papillary thyroid carcinomas (PTC) predominantly metastasize to lymph nodes. This different behavior of cancer cells originating from one organ was investigated by layering multicellular tumor spheroids (MCTS) consisting of various kinds of human thyroid cells onto confluent monolayers of human venous endothelial cells (HEC). The MCTS and HEC were cocultured in an incubation chamber fixed under a microscope, and the behavior of the cells was investigated. In this way significant differences between FTC, PTC, and follicular adenoma cells (FTA) were observed regarding their in vitro behavior upon interaction with HEC. FTC cells required 20 min for adhesion and another hour until they migrated out of a spheroid, whereas PTC- and FTA-MCTS were adhesive after 2 h or later, and their cells did not start migration until 5 h of incubation. Furthermore, one FTC-spheroid triggered about 100 endothelial cells to enter the replication cycle, while no spheroid consisting of either PTC or FTA cells induced more than 20 endothelial cells to start proliferation. During these processes, the cells of the MCTS and the endothelial cells contacted each other directly and remained viable. The results show that FTC cells interact faster and more intensively with human endothelial cells than PTC and FTA cells. Thus the study suggests that an enhanced capability of the FTC cells to interact with venous endothelial cells might favor the clinically observed hematogenous spreading of follicular thyroid carcinomas.
Thyroid 1995 Jun
PMID:Human follicular and papillary thyroid carcinoma cells interact differently with human venous endothelial cells. 758 Feb 62

The purpose of the study was to examine the value of a commercial immunoradiometric (IRMA) method for measuring serum thyroglobulin as a tumor marker after treatment for differentiated thyroid carcinoma. A prospective analysis of consecutive serum samples from 53 patients was performed using the IRMA method and a traditional double antibody radioimmunoassay (RIA). The results were compared with those of 100 healthy control subjects and furthermore the method was validated by investigating sera from 24 patients with Hashimoto's thyroiditis positive for thyroglobulin autoantibodies. Finally, in vitro studies of the influence of thyroglobulin autoantibodies on the method were done. The IRMA method had an acceptable analytical precision and was more sensitive than the RIA. It was furthermore less sensitive to the presence of thyroglobulin autoantibodies but it was affected by them, and it showed less unspecific serum effect. Both methods had limitations as tumor marker when the patients had a thyroid remnant, when serum thyrotropin was not suppressed, and in cases of local recurrence. The highest predictive value was found in patients with distant metastases. Thus, in cases of only slightly elevated serum thyroglobulin, the strongest indication for recurrence is still an increasing serum thyroglobulin level within the same patient rather than a single value.
Thyroid 1995 Jun
PMID:Assessment of the influence of thyroglobulin (Tg) autoantibodies and other interfering factors on the use of serum Tg as tumor marker in differentiated thyroid carcinoma. 758 Feb 63

A 61-year-old Caucasian man presented with otalgia, dysarthria, and weight loss. Neurological examination revealed palatal hypomotility, and weakness of the facial and tongue muscles. Magnetic resonance imaging of the head demonstrated the presence of a soft tissue mass in the clivus. Histologic examination of resected tumor disclosed well-differentiated thyroid follicles that invaded the local osseous tissues. Physical examination and radioiodine images of the thyroid gland were normal. The serum thyroglobulin concentration was markedly elevated (1011 ng/mL). A 0.9-cm well-differentiated benign-appearing left thyroid lobe follicular neoplasm with a thick fibrous capsule was found following diagnostic thyroidectomy. This report illustrates that clinically significant distant metastases can arise from occult follicular thyroid neoplasms that, according to standard histologic criteria, are benign. The presence of a thick fibrous capsule, even in the absence of vascular or capsular invasion, may identify follicular neoplasms that have metastatic potential.
Thyroid 1995 Jun
PMID:Metastatic follicular thyroid carcinoma masquerading as a chordoma. 758 Feb 71

The use of radioactive isotopes in thyroid evaluation and therapy gives important information in the endocrine assessment of the aged. Thyroid uptake imaging can be used to establish a hypothyroid or hyperthyroid state and can determine the functional status of a palpable nodule. Investigational agents, such as T1 201m DMSA, MIBG, FDG, and Gallium are reviewed in relation to the evaluation of neoplasia. A detailed discussion of thyroid carcinoma ablation and subsequent radioiodine therapy is described, as are radiation safety procedures as they relate to the elderly.
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PMID:Radioisotopes and their use in the diagnosis and management of thyroid disease. 760 90

The mechanism of the impaired response to thyrotropin (TSH) in thyroid tumor cells was investigated by searching for structural changes in the TSH receptor (TSH-R) in neoplastic thyroid tissues in humans. Total RNA was prepared from 34 thyroid tissue samples (four normal, six adenoma, six follicular cancer, and 18 papillary cancer) and reverse- transcribed into single-stranded cDNA, which was then used as a template for the polymerase chain reaction and subjected to single-strand conformation polymorphism (SSCP) analysis. Two fragments, FRAG (468-692) (nucleotides 468 to 692, corresponding to the mid-portion of the receptor extracellular domain) and FRAG (2044-2295) (nucleotides 2044 to 2295, corresponding to the COOH-terminal, cytoplasmic domain of the TSH-R cDNA) showed differences in electrophoretic mobility among the various thyroid tissue samples. Direct sequencing revealed Phe197 (TTC) --> Ile(ATC), and Asp219 (GAT) --> Glu(GAG) substitutions in FRAG (468-692) from two papillary cancers. Three types of substitution were identified in FRAG(2044-2295): Asn715 (AAC) --> Asp(GAC) from one papillary cancer, Lys723 (AAG) --> Met(ATG) from one papillary cancer, and Asp 727 (GAC) --> Glu(GAG) from one normal tissue sample, one follicular cancer, and four papillary cancers. These results suggest that there exist structural changes in TSH-R in some cases of thyroid neoplastic tissue.
Thyroid 1995 Apr
PMID:Point mutations in the thyrotropin receptor in human thyroid tumors. 764 78


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