The Expression Of Survivin,P53 Gene In Thyroid Papillary Carcinoma

Thyroid carcinoma is one of the most common cancer. The carcinogenesis and development of thyroid carcinoma is multistage and associated with multigene mutated. Survivin is a member of the IAP family. It is not highly expressed in most adult tissues, but high levels have been seen in fast growing cells, Such as transformed cell lines and human cancer cells. Deficiency for survivin induces cell death, and over expression of survivin confers resistance to cell death. However, whether survivin is directly involved in the regulation of apoptosis remains controversial. In vitro, survivin binds to caspases and inhibits their activation, just as other IAP family nembers do. In particular, survivin seems to regulate the localization and activation of caspase-3 during mitosis. It has also been proposed that a splicevatiant of survivin might locate to mitochondria, and regulate intrinsic apoptosis pathways, Rather than controlling apoptosis. The primary function of survivin seems to regulate of mitotic progression. The survivin gene is highly conserved in a wide range of organisms, and all orthologues are involved in mitotic regulation. P53 is mutated in more than 50% of human cancers. Defects in cell-death pathways are hallmarks of cancer, although resistance to apoptosis is closely related with tumorigenesis. Tumour cells can still be induced to die by non-apoptosis mechanisms such as necrosis senescence autophagy and mitosis catastrophy. The molecular pathways that underlie these non-apoptotic responses remain unclear. Several apoptosis and non-apoptosis pathways of cell death have been defined in normal physiology and during tumorigenesis. The inactivation of mitotic-checkpoint molecule survivin could induces the death of P53-deficient cells by mitotic catastrophe. Up to new, the study of survivin and P53 expression in thyroid papillary carcinoma has not been much reported.Objetive: To detect the expression of a novel apoptosis inhibitory gene survivin and the mutant type p53 gene in thyroid papillary Carcinoma and their relationship with clinicopathological features.Materials and Methods: The expression of survivin, P53 gene was observed by immunohistochemistry SP method in 102 specimens of thyroid papillary carcinoma and 10 specimens of thyroid nodular goiter. X~2-test was used for statistical analysis ofresearch data. There was statistical significance when P<0.05 occurred.Results: The positive rates of expression of survivin and mutant type p53 gene were 66.7% and 81.4% in thyroid papillary carcinoma , respectively. In group of mt-p53 postive expression in thyroid papillary carcinoma, the postive rates of expreesion of survivin was 79.5%, while in no mt-p53 expression group, the postive rates of expression of survivin was 10.5% , the difference being significant (p<0.05) . In group of high expression of mt-p53, the postive rates of expression of survivin was 95.6%, while in group of mt-p53 expression low postive group,the postive rates of exprssion of survivin was 60.5%, the diffierences also being signicant (p<0.05) . No mutant p53 expression in nodular goiter. The positive rates of expression of survivin gene in nodular goiter was 30%. No significant relationship were found between the expression of survivin and mt-p53 gene and sex, agen tumour size (< lcm, l-4cm, >4cm), gross type, histological subtype and histological differentiation grade (P>0.05) . The expressin of mt-p53 gene in thyroid papillary carcinoma has no relationship with lymph nodesmetastasis. The postive rates of expression of survivin gene in thyroid papillary carcinoma with lymph nodes metastasis was 79.5%, while it was 57.1% in group of whitout lymph nodes metastasis. The differences are significant (P<0.05) .Conclusion:? The survivin and mt-p53 gene overexression in thyroid papillary carcinoma .?The expression of Survivin and mt-p53 gene inthyroid papillary carcinoma not correlates with sex, age% tumour size -> gross type > histological subtype > histological differentiation grade .?The expression of mt -P53 gene in thyroid papillary carcinoma not correlates with lymph nodes metastasis, while the expression of survivin gene in thyroid papillary carcinoma significantly correlates with lymph nodes metastasis.(4) The expression of survivin gene is significantly correlates with the expression of mt-p53 gene. The expression of survivin is higher in mt-p53 over-expression group than that in mt-p53 low-expression group. The expression of mt-p53 and survivin gene might play synergetic roles in the process of carcinogenesis of thyriod papillary carcinoma.