Expression of ubiquitin conjugating enzyme UbcH10 in brain astrocytomas

Abstract

Objective To investigate the expression ofubiquitin conjugating enzyme UbcH10 gene at mRNA and protein levels in brain astrocytomas and its correlation to the pathological grades of astrocytomas. Methods Quantitative real-time RT-PCR analysis, immunohistochemistry and Western blot were performed to detect the expression of UbcH10 mRNA and protein in 32 astrocytomas of different pathological grades and 6 normal brain tissues. The correlation between UbcH10 and Ki-67 immunoreactivity was examined with the Spearman's correlation coefficient. Results Statistical analysis showed significantly increased expression levels of UbcH1O mRNA in high-grade astrocytornas (64.33±60.98) in comparison with those in low-grade astrocytomas (8.36±8.15) and normal brain tissues (1.00±1.57) (P<0.05). increased UbcH10 labeling index in immunohistochemistry was also noted in high-grade astrocytomas [(9.65±5.75)%] as compared with that in low-grade astrocytomas [(4.82± 3.30)%] (P<0.05) and normal brain tissues [0%, P<0.05). Western blot demonstrated significantly higher UbcH10 protein levels in high-grade astrocytomas (0.69±0.38) than in low-grade astrocytomas (0.10±0.08, P<0.05) and normal brain tissues (0.01±0.02, P<0.05). UbcH10 positivity rate was found to positively correlate to that of Ki-67 (r=0.67, P=0.000). Conclusion Overexpression of UbcH10 may play an important role in the development and progression of astrocytomas. Key words: Glioma; Astrocytoma; UbcH10; Ki-67