metallothionein and Goiter--Nodular

The expression of metallothionein I/II (MT-I/II) was examined in thyroids of Graves' disease (GD) and nodular goiter (NG) patients to determine its role as a potential marker of proliferation and autoimmune inflammation in the thyroid.. MT-I/II and Ki-67 antigen expression was studied using immunohistochemistry in 72 GD and 24 NG patients.. MT-I/II expression was noted in the cytoplasm and nuclei of thyrocytes of GD and NG patients. Cytoplasmic and nuclear MT-I/II expression correlated strongly with GD (r=0.51; p<0.0001) and NG (r=0.50; p=0.0137). Cytoplasmic MT-I/II expression was significantly higher in GD (mean IRS 9.24±2.36) than in NG (mean IRS 7.13±2.51; p=0.0006) and correlated positively with Ki-67 antigen expression (r=0.28; p=0.0165). Nuclear MT-I/II expression was elevated in GD (mean 3.53±0.65) in comparison to NG (mean 2.96±0.86; p=0.028).. MT-I/II may be a potential marker of GD in the thyroid and may be potentially involved in thyrocytes' proliferation.

Topics: Adolescent; Adult; Aged; Cell Nucleus; Female; Goiter, Nodular; Graves Disease; Humans; Immunohistochemistry; Ki-67 Antigen; Male; Metallothionein; Middle Aged; Thyroid Gland; Young Adult

Metallothioneins (MTs) are involved in numerous cell processes such as binding and transport of zinc and copper ions, differentiation, proliferation and apoptosis, therefore contributing to carcinogenesis. Scarce data exist on their expression in benign and malignant lesions of the thyroid.. mRNA expression of functional isoforms of MT genes (MT1A, MT1B, MT1E, MT1F, MT1G, MT1H, MT1X, MT2A, MT4) was studied in 17 nodular goiters (NG), 12 follicular adenomas (FA) and 26 papillary thyroid carcinomas (PTC).. One-way ANOVA revealed significant differences in mRNA expression levels of MT1A (p<0.05), MT1E (p<0.005), MT1F (p<0.0001), MT1G (p<0.005), MT1X (p<0.0005) and MT2A (p<0.005) in the analyzed samples. Post hoc analysis confirmed a significantly lower expression of MT1A mRNA in PTC compared to NG (p<0.05). Significant down-regulation was also noted for other MT isoforms in PTC in comparison to NG: MT1E (p<0.05), MT1F (p<0.0001), MT1G (p<0.005), MT1X (p<0.0005) and MT2A (p<0.05). In addition, significant down-regulation of MT1F and MT1G in FA compared to NG was observed (p<0.005 and p<0.05, respectively).. Expression of functional MT isoforms may contribute to thyroid carcinogenesis and potentially serve as a diagnostic marker in distinguishing benign and malignant lesions.

Topics: Adenoma; Adult; Aged; Aged, 80 and over; Carcinoma; Carcinoma, Papillary; Female; Gene Expression Regulation, Neoplastic; Goiter, Nodular; Humans; Male; Metallothionein; Middle Aged; Protein Isoforms; RNA, Messenger; Thyroid Cancer, Papillary; Thyroid Neoplasms; Young Adult