Abstract:Objective To investigate the expressions of a disintegrin and metalloprotease domain 17 (ADAM17), epidermal growth factor receptor（EGFR）and proliferating cell nuclear antigen （Ki-67）in brain glioma tissues of different malignant degree. Methods The fresh specimens of human brain glioma (n=40, brain glioma F group) were collected from January to December 2014 and divided into low malignancy group (n=20) and highly malignant group (n=20) according to malignant degree. The fresh brain tissue specimen of surgical decompression for traumatic brain injury were selected as control group （n=20）at the same time. Western blot method was used to detect the expressions of ADAM17 and EGFR in the fresh specimens. On the other hand, paraffin block tissues (n=60, brain glioma group P) of brain glioma were collected from January 2010 to January 2013 and divided into low malignancy group（n=23）and highly malignant group （n=37） according to malignant degree, and the paraffin block tissues of surgical decompression for traumatic brain injury were served as control group（n=9）at the same time. Immunohistochemical SABC methodwas used to detect the expressions of ADAM17, EGFR and Ki-67 proteins, which in different specimens and different malignant degree tissues were compared with those in control group. Statistical test level was α=0.05, and it was corrected as α′=0.017 when using R×C table Chi-square test segmentation method. Results Western blot method for fresh specimens showed that(1) the expression of ADAM17 was very low, and no expression of EGFR was found in control group. (2) the expressions of ADAM17 and EGFR in low malignancy group （0.32±0.05，0.46±0.07）and highly malignant group （0.80±0.14，1.16±0.15）increased significantly, and they in highly malignant group were significantly higher than those in low malignant group （all P<0.01）. Immunohistochemical SABC method for paraffin block specimens showed that （1）the expression of ADAM17 protein mainly was weakly positive in control group and mainly was positive and strongly positive in brain glioma group; positive expression rate of ADAM17 protein in brain glioma group was significantly higher than that in control group （80.0% vs 22. 2%, P<0.01）and significantly increased in highly malignant group compared with low malignant group （94. 6%vs 56. 5%, P<0.017）. （2）EGFR protein was not expressed in the brain tissue of control group and mainly was positive and strongly positive expressed in brain glioma group; the positive expression rate ofEGFR protein in brain glioma group was significantly higher than that in control group （70.0% vs 0, P<0.01）and significantly increased in highly malignant group compared with low malignant group （73. 0% vs 39. 1%, P<0.017）. （3）the expression of Ki-67 protein was all negative in 9 cases of control group, and the positive rate of Ki-67 protein in brain glioma group was significantly higher than that in control group（63. 3% vs 0, P<0.01）and significantly increased in highly malignant group compared with low malignant group （86. 5% vs 26. 1%，P<0.017). Conclusions The expressions of ADAM17, EGFR and Ki-67 increase in brain glioma tissues, and the levels of expression obviously increase with the increase of malignant degree. High expressions of ADAM17 and EGFR are closely related to the proliferation of brain glioma cells.