The Role Of Pituitary-specific Transcription Factor-1 In Biology Behavior Of Pituitary GH Adenomas

part1The biological significance of pit-1 and c-myc expression in pituitary GH adenomasObjective 1 To investigate the pituitary-specific transcription factor (Pit-1) and c-myc expression on human pituitary adenomas.2 To study the relationship between the pituitary-specific transcriptionfactor (Pit-l),c-myc and the of growth hormone in human pituitary growth hormone adenomas, and to analyse the relativity to them.3 To gain further insight about the value of the pituitary-specifictranscription factor (Pit-1) and c-myc on pathogenesis of pituitary growth hormone adenomas. Methods Mensuration the expression of Pit-1, C-myc on pituitary growth hormoneadenomas by SABC immunohistochemistry method.Results 1 There were high expressions of Pit-1 on all pituitary growth hormone adenomas, compare with control group, the differences of their expression levels were statistically significant P<0.05. There were positive relativity between the expressions of Pit-1 and the level of growth hormone.2 In 26 cases, the expressions of C-myc was obtained in 19 caess(73.1%). compare with control group, the differences of their expressin levels were statistically significant P<0.05. There are positive relativity between the expressions of c-myc and the level of growth hormone. Conclusion 1 There were high expressions of Pit-1 on all pituitary growth hormone adenomas. The expressions levels were positive relativity to the level of growth hormone. The expression of Pit-1 was associated with adenomas biological behaviour, so it has a important role in pathogenesis of pituitary GH adenomas.2 There were high expressions of c-myc on most pituitary growth hormone adenomas. It had a positive relativity to the level of growth hormone. It acted as a important action on the cell proliferation and invasive ability.Part 2The study of effect on the biological action of GH adenomas by inhibition of the expressions of pit-1Objective 1 To explore the effect of pit-1-AODN on cell proliferation and the levelof growth hormone, in GH adenomas. 2 To observe the action of pit-1-AODN on induce apoptesis and change the cell periods.3 To study the control of pit-1-AODN to the expressions of Pit-1,pit-1-mRNA and C-myc, c-mycmRNA in GH adenomas.4 To investigate the correlativity between pit-1 and c-myc,and to studythe mechanism ahout pit-1-AODN inhibited cell proliferation, the level of growth hormone, and induce apoptesis. Methods 1 pit-1-AODN was designed that penetrate cells by lipofectin, which isantisense gene seal to seal aim gene.2 The changes of proliferation rate, the level of GH, cell apoptosis andthe expressions of Pit-1, pit-1-mRNA å’ŒC-myc, c-mycmRNA werestudied by MTT assay, RIA, FCM, SABC immunohistochemistry andRT-PCR.Results 1 pit-1-AODN markly inhibit the proliferation of GH adenomas cell indoes-dependent and time-dependent in a certain range. 2 pit-1-AODN inhibit the level of GH in does-dependent and dependent-time in certain range. The inhibit rates were : 9.23%, 23.1%, 46.0% in 24, 48, 72h at 20μmol/L group. There were statistically significant P<0.05 among groups.3 Compared with control group, pit-1-AODN induced cells apoptosis after 48h, and markedly at 72h (P<0.01). cells stopped at G₂/M phase, and the number of apoptosis cells increased as time went on in a certain range.4 The expressions pit-1, pit-lmRNA were detected in all 12 cases. C-myc, c-mycmRNA were detected in 9 cases. When pit-1-AODN added, The expressions pit-1, pit-lmRNA and C-myc, c-mycmRNA decreased dramatically(P<0.01).Conclusion Pit-1AODN can markly inhibit the cells proliferation and the level of growth hormone. in GH adenomas. It can decrease dramatically the expressions of pit-1, pit-1mRNA and-myc, c-mycmRNA. Part 3The effect of pit-1 antisense oligodeoxynucleotide on Octreotide on the inhibition of GH adenoma cellsObjective 1 To explore the effect of pit-1AODN on cell proliferation of Octreotide and the level of growth hormone and cells apoptosis in GH adenoma.2 To study the change of the expressions of pit-1 and c-myc protein and the change of cells invasiveness in GH adenomas.3 Compared with Octreotide, the effect and the potential prospect ofpit-1-AODN on treatment GH adenoma were evaluated .Methods 1 The effect of pit-1AODN on Octreotide to cell proliferation,the level of growth hormone, in GH adenoma and cells apoptosis were measured by MTT,RIA and FCM.2 The changes of the expressions of pit-1 and c-myc protein in GH adenomas for using pit-1AODN and Octreotide by Western blot.3 The changes of GH adenomas cells invasiveness was evaluated byBoyden chamber.Results 1 Compared with Octreotide, the inhibition rate of cells proliferation was statistically significant (P<0.05) by pit-1AODN at 96,120h. Using pit-1AODN and Octreotide together, there were a good coordination. 2 At 48h, there was a statistically significant (P<0.05) on pit-1AODN and Octreotide in inhibition of the level of growth hormone. Compared with B,C groups, there were high statistically significant (P<0.01) on D group. 3 In AODN group, GH adenomas cells were increased at G₂/M phase as time went on. The efficacy had depended-time in a certain range. In Octreotide group, cells increased at G₀/G₁ phase and decreased at S phase. The ability of pit-1AODN to induce cells apoptosis was superior to B or C group.4 The effect of pit-1AODN on inhibition the expressions of pit-1 and c-myc protein, and depression cells invasiveness were better than Octreotide.Conclusion 1 pit-1AODN and Octreotide all could markly inhibit the cells proliferation and the level of growth hormone. But the effect of pit-1 AODN was earlier and better than Octreotide.2 pit-1AODN and Octreotide all could increase cells apoptosis andchange cells cycle by different pathway.3 pit-1AODN was superior to Octreotide in inhibition the expressionsof c-myc protein and depression cells invasiveness.4 There was potential prospect on pit-1 as a target to treatment GHadenomas.