Expression of autocrine human growthhormone (hGH) as a key factor in the oncogenesis of glioblastomamultiforme

Background: Glioblastoma multiforme (GBM) is one of themost malignant forms of brain cancer which is associated withpoor prognosis. Despite various treatment efforts includingmaximal surgical resection if feasible, followed by a combination of radiotherapy and/or chemotherapy, the average survivaltime is about ۱۲-۱۸ months. Given the high morbidity andmortality associated with aggressive GBMs, identifying thepotential factor promoting this process is of major health significance.Increased expression of the growth hormone/IGF-Iaxis is associated with the risk of oncogenesis. Tumor derivedautocrine human growth hormone (hGH) has been implicatedin development and progression of some tumors through inductionof cell proliferation, angiogenesis, and immortalization.However, the potential expression of hGH in GBMs remainslargely to be determined.Materials and Methods: We used twenty-five samples of GBMtumors and four samples from the healthy brain as control. Allsamples transferred in liquid nitrogen and stored at –۸۰°C untilRNA isolation. Total RNA extraction was performed using Trizolreagent and then converted to cDNA. Real-time PCR wasused to evaluate the expression level of GH geneResults: The expression of human growth hormone gene (hGH)were significantly increased in tumor samples in comparisonto normal tissue samples (p value < ۰.۰۵). However, the resultshowed various expression pattern among all patients.Conclusion: This study may highlight the mechanism thatGBM tumors have a local regulation for GH expression topromote cell proliferation and survival. Hence, inhibition of Fsignaling may be a potential novel therapeutic modality againstGBMs

کلیدواژه ها:

Glioblastoma multiforme ، growth hormone ، autocrineexpression ، potential oncogenesis ، cancer progression