Summary
In order to investigate the relationship between abnormal intracellular signal transduction and tumorgenesis of human pituitary somatotrophinomas, the effects of protein kinase A (PKA)-de-pendent growth hormone (GH) releasing hormone (GHRH) and protein kinase C (PKC)-dependent GH-releasing peptide (GHRP-6) on cAMP production were observed by using cell culture and biochemical methods, and the expression of the gsp oncogene was detected by using PCR and direct sequence assay methods in 11 patients with human pituitary somatotrophinomas. It was found that GHRP-6 exerted significant stimulatory effect on cAMP production by 2 gsp-positive tumors and no effect on the gsp-negative tumors. GHRP-6 could enhance the stimulation of cAMP production induced by GHRH in tumor without gsp oncogenes. It was suggested that both GHRH and GHRP-6 exert identical effects on human pituitary soamtotrophinomas, which was contributed to the crosstalk between the two intracellular signal transduction pathways in pituitary cells.
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References
Lei T, Adams E F, Buchfelder Met al. Relationship between protein kinase C and adenylyl cyclase activity in the regulation of growth hormone secretion by human pituitary somatotrophinomas. Neurosurgery, 1996, 39:569
1997, 35:328
Gsp 2000, 17:53
1999, 16:190
Liu Q, Lei T, Adams E Fet al. Relationship between GHRP-6 and TPA in the regulation of growth hormone secretion by human pituitary somatotrophinomas. J Tongji Med Univ, 1997, 17:132
Liu Q, Bai X J, Liu Ket al. The Effect of GHRH, GHRP-2 and somatostatin on GH secretion by fetal pituitary. J Tongji Med Univ, 1999, 19:277
Yoshimasa T, Sibley D R, Bouvier Met al. Cross-talk between cellular signalling pathways suggested by phorbol-ester-induced adenylate cyclase phosphorylation. Nature, 1987, 327:67
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This project was supported by the grants from National Natural Science Foundation of China (No. 39670736), Deutsche Gesellschaft fuer Zusammenarbeit (No. 93. 2254. 6-02.196) and Health Ministry (No. 96-2-14).
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Ting, L., Qin, L., Luo, L. et al. Preliminary study on the relationship between cAMP level and gsp expression in cultured human pituitary somatotrophinomas. Current Medical Science 20, 214–216 (2000). https://doi.org/10.1007/BF02886994
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DOI: https://doi.org/10.1007/BF02886994