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Comparative Study 2007; 28(4): 341-350 PubMed PMID: 17693985 Citation  Keywords:  Adenoma:diagnosis, Adolescent, Adult, Aged, Biomarkers, Tumor:metabolism, Biopsy, Carcinoma, Medullary:diagnosis, Carcinoma, Papillary:diagnosis, Cyclin D, Cyclins:metabolism, Female, Gene Expression Regulation, Neoplastic, Goiter, Nodular:diagnosis, Huma.   

OBJECTIVE: Cyclin D1, encoded by CCND1 (cyclin D1) gene with locus in chromosome 11q13, is a protein that plays the key role in the passage through the restriction point in G1 phase of cell cycle. The aim of the study were: 1) an assessment of CCND1 gene expression level in benign and malignant thyroid lesions and 2) the evaluation of possible correlations between gene expression and the histopathological variants of papillary thyroid carcinoma (PTC), or tumour size, classified according to TNM definition of primary tumours (in case of PTC only) or patient's sex or age.

DESIGN: Thirty five (35) tissue samples were analysed: 24 cases of PTC, 4 cases of medullary thyroid carcinoma (MTC), 4 cases of follicular adenoma (FA) and 3 cases of nodular goitre (NG). In real-time polymerase chain reaction (real-time PCR), two-step RT-PCR (reverse transcriptase-polymerase chain reaction) in an ABI PRISM 7500 Sequence Detection System was employed. Cyclin D1 gene expression level was assessed, calculating the mean relative quantification rate (RQ rate) increase for each sample.

RESULTS: The level of cyclin D1 gene expression was significantly higher in malignant thyroid tumours (PTC, MTC), as compared with that in macroscopically unchanged thyroid tissue, FA and/or NG groups. However, the differences of RQ rate value between different PTC variants were statistically insignificant. No correlation was found between RQ values and patients' sex or age. On the other hand, the correlation was observed between RQ values and tumour size.

CONCLUSIONS: Cyclin D1 gene expression in various thyroid lesions may be helpful in diagnostically doubtful cases. However, our results--mostly due to the small numbers of cases in the groups other than PTC--do not yet allow considering cyclin D1 gene as a molecular prognostic marker....

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Journal Article 2003; 24(5): 310-313 PubMed PMID: 14647002 Citation  Keywords:  Animals, Antioxidants:pharmacology, Circadian Rhythm, Cyclin-Dependent Kinase Inhibitor p21, Cyclins:metabolism, Male, Melatonin:pharmacology, Rats, Rats, Wistar, Thyroid Gland:cytology,.   

OBJECTIVES: The cell-cycle (cc) is, in part, controlled by cyclin-dependent kinases (CDKs), which are activated after binding cyclins (positive regulators of cc). CDK inhibitors (CDKIs), such as p15, p16, p21, and p27, inhibit cyclin-CDK complex activity, and function as negative cell cycle regulators, blocking cell-cycle progression. The aim of our study was to examine the influence of late-afternoon (1600-1800) subcutaneous (s.c.) melatonin (Mel) injections, administered for 2 weeks, on the p21 expression in male Wistar rat thyroid follicular cells (TFC).

METHODS: In order to detect the anti-p21 antibodies, the DAKO LSAB2 Rat Kit/HRP (DAKO, USA) and DAKO Liquid DAB Substrate-Chromogen System (DAKO, USA) were employed.

RESULTS: No statistically significant changes of p21(LI) (p21 labelling index) values were observed in particular groups of the rats receiving Mel injections, in comparison to the controls. The statistical difference of p21(LI) values (p<0.03) was only observed between groups of rats, receiving Mel injections in the dose of 25 microg/daily and 100 microg/daily.

CONCLUSION: Melatonin - in the applied doses and in the experimental conditions without any factors revealing anti-DNA activity - did not change, in any statistical way, p21 expression in rat thyroid follicular cells, as compared to the control group....

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