| It has been demonstrated that activation of oncogene and inactiva-tion of tumor suppressor gene disturb the normal regulation of the cell proliferation and differentiation, which lead to hyperplasia and poor differentiation of cells. Tumorigenesis is not only related to the growing speed of cells, but also to the mortality speed of cells. The defect or block of apoptosis is also an important factor that results in the occurrence and development of tumor. So cancer is the disease of abnormal proliferation and differentiation of cells, and the disease of abnormal apoptosis. Because of the rapid development of the molecular biology, more novel genes, such as survivin, have been paid attention to and become the new focus. Pituitary adenomas are commonly in-tracranial neoplasms, which are benign in histology. However, the growth speed of tumor cells is significantly difference, about one third of them show malignant biological behavior, invading the cavernous sinus and surrounding bones,so it is difficult to resect them completely and the tumors recur frequently after operation. The pathogenesis of invasive pituitary adenomas isn' t clear at present, and their diagnosis is indirectly made mostly dependent on radiological manifestation, survivin gene, a new inhibitor of apoptosis, has been reported to be highly similar to the reverse complement of the EPR - 1 gene, located on chromosome 17q25 , containing 4 exons and 3 introns. survivin gene is found during embryonic and fetal development but is completely down - regulated and undetectable in normal adult tissues and becomes prominently reexpressed in several human malignancies, including cancers of the colon, stomach, pancreas, lung, prostate, and breast. As a result of its selective expression in malignant cells but not in surrounding normal tissues, survivin gene has generated much interest for its role as a target for anti - cancer drugs and as a novel marker of prognosis in malignancies. To our knowledge, the relation between survivin expression and apoptosis , tumorigenesis, bcl - 2 or p53 has not yet been studied in pituitary adenoma.Objective Purpose of this study was to examine the apoptotic cell and the expression of a novel antiapoptosis gene, survivin, in normal pituitary tissues and pituitary adenoma tissues, and to study theeffects of apoptosis in the occurrence and development of pituitary ade-noma , and the relationship between survivin and bcl - 2 , p53 in controlling pituitary adenoma cell apoptosis.Materials and Methods Fourty - eight pituitary adenoma samples and 8 normal pituitaiy samples were collected. All of the tissues were fixed in 10% neutral formalin and enbedded in paraffin. TUNEL (terminal deoxynucleotidyl transferase mediated dUTP nick end labeling) method was used to evaluating the cell apoptosis index (AI) , and S - P ( streptavidin - biotin peroxidase ) immunohistochemical assay was adopted to detect the survivin , bcl - 2 , and p53 expressions in normal and adenoma pituitary tissues. Statistical analysis; the SPSS 10. 0 software wrap was used, a =0. 05 was the level of test.Results1. In 48 cases , the positive rate of apoptotic cell was 89. 6% (43/48) , The apoptosis index (AI) of noninvasive pituitary adenoma was 12. 6% , and 2. 7% in invasive pituitary adenoma (P <0. 05) .2. In pituitary adenoma tissues the rate of positive expression of survivin gene was 66.7% (32/48). In contrast, normal pituitary tissues did not express survivin. In clinical type of invasive pituitary adenoma , the positive rate of expression of survivin gene is 8 1 . 5 % ( 22/ 27) in invasive pituitary adenoma, and 47. 6% (10/21) in noninvasive pituitary adenoma ( P < 0. 05 ) .3. The positive rate of expression of survivin gene is 78. 8% (22/ 32) in secreting type (functional) , and 62. 5% ( 10/16) in non - se-creting type( non - functional) , P >0. 05.4. The positive rate of expression of survivin gene (77. 8% ) in the pituitary adenoma tissues whose expression of bcl - 2 gene is positive is higher than t...
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