[Evaluation of the expression of survivin-3b and survivin-3alpha ,the novel splice variants, as diagnostic tumor markers in thyroid cancer]

Survivin is a new member of inhibitor of apoptosis protein family [IAP] that plays an important role in the regulation of cell cycle and inhibition of apoptosis. Distinct expression of this gene in tumoral cells versus normal cells introduces it as the fourth major transcriptome in cancers. Thyroid carcinoma is the most common endocrine malignancy. Considering the highly heterogeneous nature of tumoral and non-tumoral thyroid nodules from the pathological viewpoint and also in regard to the absence of appropriate molecular markers, extensive efforts have been made to find a specific molecular tumor marker for diagnosis of thyroid tumors. Studies have been demonstrated that the expression pattern of survivin and its splice variants was different in cancerous tissues compared to normal tissues. In this study we evaluated expression of survivin-3b and survivin-3alpha, the novel survivin splice variants, as diagnostic markers for thyroid cancer. This was a descriptive study. 77 thyroid specimens; including 49 tumoral, 14 non-tumoral and 14 tumor margin samples were collected and expression of survivin-3b ands-3alpha was investigated by hemi-nested RT-PCR method. Tumoral samples showed the highest expression of survivin-3b and survivin-3alpha and the lowest expression was detected in the specimens of tumor margins. In this study we demonstrated the expression of survivin-3b and survivin-3alpha in thyroid tumors for the first time. In conclusion significant expression of survivin-3b and survivin-3alpha splice variants in tumoral cells shows their roles in thyroid cancer progression and their efficiency as molecular markers for detection and classification of tumoral and nontumoral thyroid nodules

[Evaluation of the expression of Survivin-2 alpha splice variant as a molecular marker in thyroid cancer]

Thyroid carcinoma is the most common endocrine malignancy. Considering highly heterogenous nature of tumoral and non-tumoral thyroid nodules from pathological point of view and also in regard to absence of appropriate molecular markers, extensive efforts have been made to find a molecular tumor marker for specific diagnosis of thyroid tumors. Recent attention has been paid to Survivin, a new member of the Inhibitor of Apoptosis Protein Family [IAP], as a new molecular marker in cancer. Studies have been demonstrated that Survivin and its splice variants have different expressions in cancerous tissues compared to normal tissues. In this study the expression of Survivin-2alpha splice, one of the newest Survivin variants, was evaluated in thyroid cancer as a molecular marker. Tissue samples were collected from 77 thyroid specimens including 49 tumoral, 14 nontumoral and 14 tumor margin samples. The expression of Survivin-2 alpha was studied by Hemi-Nested RT-PCR method. Expression of Survivin-2 alpha splice was the highest in surgical margin samples compared to non-tumoral and tumoral samples. The lowest expression was that of tumoral samples. Our data demonstrated the expression of Survivin-2 alpha in thyroid tumors. Although the expression of surviving-2 alpha splice variant in tumoral cells was lower than that of tumor margins, it did not show a significant difference. Therefore it seems likely that it does not have a special role in the progression of tumor and development of abnormal nature of the cells. According to the results of this study, it can be concluded that the different expressions of 2 alpha in these groups can not be an appropriate criterion for distinguishing tumors from non-tumoral lesions of thyroid gland