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F Juhasz

Publications and source records attributed to F Juhasz.

13 recordsLinked to original sources

Gene profiling identifies genes specific for well-differentiated epithelial thyroid tumors.

Thyroid nodules are common. It would very helpful if genetic markers that can diagnose malignancy from fine needle aspiration samples were available. Few such markers has been thus identified and none are specific. Large panels of potential markers can be screened by microarray technology. Studies done to date have concentrated on single tumor types and thus provide no help in identifying tumor subtype specific markers. To that end we have studied gene profiles of 5 types of benign and malignant thyroid nodular tissue (multinodular goiter, follicular adenoma, papillary and follicular carcinomas). We have identified 195 genes whose differential expression clustered into clinically relevant groups. Twenty-eight genes were selected for further confirmation using real time quantitative polymerase chain reaction. Despite the differences in the microarray panels used, we confirmed the differential regulation of 12 genes previously reported in thyroid cancer, although we found the expression of several genes to be regulated in other histological tumor subtypes than originally described. We found, PCSK2, TRIB1, RAP1 GA1 to be specifically overexpressed in follicular cancer and S100A4 and GK2 in papillary carcinoma. SERP1, RNASE 2 and STATA5 were suppressed in papillary thyroid cancer. We have thus identified new potential markers specific to malignant thyroid tumors. It is apparent that a range of nodular thyroid tissue using large tumor sample numbers is necessary to establish robust markers for malignancy and to categorize tumors on the basis of small tumor samples.

Adenocarcinoma, Follicular↗

Differentiated thyroid cancer and outcome in iodine deficiency.

AIMS: Factors influencing prognosis and long-term outcome of thyroid cancer have been described by several groups. We wished to asses the previously described prognostic factors in a moderately iodine deficient region in Hungary. METHODS: Four hundred and fifty-four out of 492 patients who had surgery for papillary thyroid cancer (PTC, 386 cases) and follicular thyroid cancer (FTC, 106 cases) between 1971 and 1998 were analyzed. Survival curves were compared using the Kaplan-Meier method and Cox regression analysis. RESULTS: The 10 and 20-year survival rates were 87.9 and 84% for PTC, and 78.2 and 78.2% for FTC. In PTC, extrathyroidal invasion (p<0.0001), lymph node metastasis (p<0.0001), distant metastasis (p<0.0001), and age over 40 years (p=0.002) were significant adverse predictors. In FTC, extrathyroidal invasion (p=0.003) distant metastases (p<0.0001), and age over 40 years (p=0.011) were significant adverse predictors. CONCLUSION: Iodine intake did not appear to influence survival. The incidence of follicular cancer, which has less favourable prognosis, was higher in iodine deficient regions. This supports the importance of iodine supplementation in these areas.

Adenocarcinoma, Follicular↗

High rates of ras codon 61 mutation in thyroid tumors in an iodide-deficient area.

Using polymerase chain reaction and sequence-specific oligonucleotide hybridization, the frequency of three ras oncogene mutations (N-ras, Ha-ras, and K-ras) in thyroid tumors (25 adenomas, 16 follicular carcinomas, and 22 papillary carcinomas) was investigated in both iodide-deficient and iodide-sufficient areas. The ras oncogene mutation rate was significantly higher in the iodide-deficient area, being 85 versus 17% in the adenomas, and 50 versus 10% in the follicular carcinomas. No mutations were found in papillary carcinomas. The most common mutation site was Ha-ras codon 61 with Gln----Arg substitution. Two ras mutations at codon 61 (Gln----Lys in N-ras and Gln----Arg in Ha-ras) were found in a microfollicular adenoma specimen from Eastern Hungary. We conclude that dietary iodine may modulate ras oncogene mutations, and that in the iodide-deficient area, ras oncogene activation may play a more important role in the initiation and/or maintenance of follicular tumors. Additional factors are, however, necessary to initiate carcinogenesis.

Adenocarcinoma↗

Cytogenetic analyses of three papillary carcinomas and a follicular adenoma of the thyroid.

Cytogenetic data of three papillary carcinomas and a follicular adenoma using direct preparations or cell cultures or both after 7 to 60 days in vitro are presented. Although karyotype of the follicular adenoma proved completely normal, in each of the three papillary carcinomas a modal chromosome number in the diploid range and a deleted 11q were observed. In case 1 the del(11)(q23) was associated with rearrangement of chromosome 1 and other marker chromosomes. Our results suggest that 11q deletion may be specific for papillary carcinoma of the thyroid.

Adenoma↗

Immunogenetic and immunologic studies of differentiated thyroid cancer.

The authors have studied in detail human leukocyte antigen (HLA) association in 87 Hungarian patients with thyroid epithelial carcinoma. The authors also examined in a small group of patients, five parameters of cell-mediated immunity and related them to HLA as well as to lymphocytic infiltration of the tumor/normal tissue interface. HLA-DR1 was significantly associated with thyroid carcinoma; the strongest association was in patients with follicular histologic features and DR1 homozygotes were not at greater risk for thyroid cancer. The HLA-DR3 was nonsignificantly increased in patients with papillary or mixed histologic features. The HLA-DR1, 3 heterozygotes were highly associated with follicular carcinoma, carried no risk for papillary carcinoma, and an intermediate risk for tumors with mixed histologic features. Because of the small proportion of DR1, 3 heterozygotes in the follicular and mixed histologic group, its predictive value at the population level was low. Better predictive potential was shown for the phenotype DR1 and/or DR3. Neither metastatic disease nor age at diagnosis (less than 45 years) could be related to HLA phenotypes. Patients in all histologic variants showed some measure of cell-mediated immunity compared to controls. Patients with papillary carcinoma showed an overall better response than those with tumors with follicular or mixed histology. The HLA-DR could not be related to cell-mediated immune response. Patients with papillary carcinoma with a good cell-mediated immune response occurred with much lower infiltration of the tumor boundary with lymphocyte whereas the follicular carcinoma less cell-mediated immunity was associated with dense lymphocytic infiltration, suggesting the biological relevance of lymphocytic infiltration may be different for the two histologic variants.

Adenocarcinoma↗

B lymphocyte subsets in Hashimoto's thyroiditis.

Two B lymphocyte subsets are identified on the basis of possession or lack of a surface molecule, CD5. The CD5+ B lymphocytes synthesize autoantibodies and in the process rearrange proximal variables of immunoglobulin genes. We have here studied the proportion and absolute counts of CD5+ B lymphocytes in the peripheral blood of 31 patients with Hashimoto's thyroiditis and related the findings to their HLA phenotypes and clinical features. Although the percentage and absolute number of surface immunoglobulin-positive (B) lymphocytes was comparable in patients to those in twenty controls, % CD5+ was significantly higher in the patient group (38.1 +/- 11.6 [+/- S.D.] vs. 27.9 +/- 10.1, p = 0.009). The absolute CD5+ cells (microliters) were also higher in patients with Hashimoto's thyroiditis (77.90 +/- 37.50 vs. 55.1 +/- 29.8, p = 0.020). The proportion of CD5+ cells was even higher in HLA-DR3 positive patients (43.1% +/- 7.2, n = 13) compared to six DR3+ controls (26.17% +/- 9.7, p = 0.0005). The difference between DR3- patients and controls was not significant (28.6% +/- 10.5 vs. 34.4% +/- 13.0). As the CD5 molecule may be induced on activated B lymphocytes, this study suggests that Hashimoto's thyroiditis is associated with an increase of activated B lymphocytes engaged in autoantibody synthesis. This defect is particularly obvious in DR3+ patients.

Antigens, Differentiation↗

Methimazole blocks Graves' IgG but not interferon-gamma HLA-DR expression by thyroid cells.

We have expanded our early observation that a potent Graves' IgG preparation induces HLA-DR expression on thyroid cells, by showing that four randomly-selected Graves' IgG's were also capable of inducing DR antigens on thyroid cells. The effect of Graves' IgG was specific to thyroid cells, as it did not induce MHC Class II molecule expression on endothelial cells whereas interferon-gamma and immune complexes did so. The anti-thyroid drug methimazole was capable of rapidly reducing Graves' IgG-induced DR expression but to a much lesser extent than brought about by interferon-gamma. We conclude that Graves' IgG propagates thyroid-specific autoaggression by continued induction of DR antigens and than an important means whereby methimazole brings about remission is by reducing this induction.

Graves Disease↗

Expression of HLA-DR antigens by thyroid cells: the effect of Graves' IgG.

We have investigated factors which influence HLA-DR expression on thyroid cells. While bTSH (100 mU/ml) did not enhance HLA-DR expression, it increased when brought about by IFN-gamma. Graves' IgG showed a dose-dependent (0.1-2 mg/ml) increase in DR expression and at a concentration of 2 mg/ml prolonged the time for which DR was expressed. The pathway of DR induction by Graves' IgG apparently differs from that by IFN-gamma. The humoral response in Graves' disease, by inducing DR expression, may be instrumental in propagating thyroid specific autoimmunity.

Autoantibodies↗

The relation of susceptibility to and biologic behavior of thyroid epithelial cell cancer to HLA-DR1.

Fifty-two patients with thyroid epithelial cell cancer were studied for evidence of association with human leukocyte antigens (HLA). Twenty-eight patients (53.8%) and 19.4% of 160 controls were HLA-DR1-positive, conferring a relative risk of 4.85 (chi 2 = 21.3, P less than 0.0001). HLA-DR1 was increased in all histologic types of thyroid cancer. Interestingly 10 of 12 patients with metastatic disease were DR1-positive compared to 18 of 41 patients without metastases (relative risk = 6.1, chi 2 = 4.7, P less than 0.05). This study suggests that major histocompatibility complex-linked gene(s) determine susceptibility to and the biologic behavior of thyroid cancer.

Antigens, Neoplasm↗

Interaction of IgG heavy-chain allotypes (Gm) and HLA in conferring susceptibility to thyroid carcinoma.

We have recently reported an increase in HLA-DR1 in 52 patients with thyroid epithelial cancer from Eastern Hungary (Juhasz et al., 1986). We have now investigated the association of IgG heavy chain markers (Gm) in 50 patients with this disease and explored possible interaction between Gm and HLA in modifying the risk for thyroid cancer. No Gm phenotype showed significant increases in the patients compared to 168 local controls. When both Gm and HLA, however, were considered, a marked heterogeneity in risk was noted. The odds ratio for DR1+fb+ homozygotes was 37.5, for DR1+fb- individuals 6.0 and for DR1-fb+ individuals 2.6 (DR1-fb- = 1.0). Thus Gm and HLA interact to enhance greatly the risk of thyroid cancer.

Disease Susceptibility↗

[Is there any decline in the frequency of perforative appendicitis? (AUTHOR'S TRANSL)].

The authors are concluding the letality of appendicitis displays a steadily declining tendency. The rate of perforations observed at their institution corresponds to the average in international surgical literature. They found that letality statistics of appendicitis improved considerably during the last century, whilst perforation percentage has remained practically the same, though the conditions in public health care and possibilities of hospitalization have considerably improved. They expect the number of perforations to decline by establishing the diagnosis even more consistently stage and by performing operations at an early stage, as well.

Adult↗

Association of goitrous autoimmune thyroiditis with HLA-DR3 in eastern Hungary.

An association of HLA-DR5 and goitrous autoimmune thyroiditis has been reported elsewhere (Farid et al., 1981; Weissel et al., 1980). Recently, the disease was found to be associated with HLA-DR4 in Newfoundlanders (Farid & Thompson, 1986). In order to find out whether different HLA associations with the disease may be found in different ethnic groups, we have now typed 68 patients with autoimmune goitrous thyroiditis from Eastern Hungary for HLA-A, -B, -C, and -DR antigens; 66 of these patients were also typed for IgG heavy-chain markers (Gm). A significant increase in DR3 (OR = 3.30) and a non-significant increase in DR4 (OR = 1.67) were found in the patients when compared with controls. The Gm3 allele, g, interacted with DR3 to enhance the risk for goitrous autoimmune thyroiditis. Hashimoto's disease may show different associations in different ethnic groups, and indeed within the same ethnic group, when newly diagnosed patients are typed several years apart.

Goiter↗