ABSTRACT
Objective To investigate the expression of glioma-associated oncogene 2 (Gli2) in giant cell tumor of bone, and analyze the differential expression in the different classification of imaging and pathology and the recurrent diseases, to discuss its role and significance in the pathogenesis and prognosis of giant cell tumor of bone. Methods 46 cases of giant cell tumor of bone who received the primary treatment in Peking University Peopleˊs Hospital during Jan 2009 and Dec 2012 and had the full data of treatment and could be follow-up were collected. Among which there were 40 benign cases and 6 malignant cases. The expression of Gli2 in the different cases of giant cell tumor of bone were detected by immunohistochemistry and real-time PCR, and its effect on the prognosis of giant cell tumor of bone was analyzed. Results Immunohistochemistry revealed positive expression of Gli2 in giant cell tumor of bone. The positive rate of Gli2 in malignant cases was significantly higher than that in benign cases [100.0 % (6/6) vs 55.0 % (22/40), P=0.035], and only found increasing trend but no significant difference among recurrent cases (P=0.204). Results of real-time PCR indicated that Gli2 highly expressed in giant cell tumor of bone, and the increasing trend of expression in different pathological types, different image classifications and recurrent cases, but no statistical different were found (all P>0.05). The expression correlation analysis showed that the expression of Gli2 and PTHrP, and the expression of RANKL and OPG either had a significant correlation (both P< 0.05). Additionally the expression of PTHrP and RANKL had a moderate correlation (P<0.05). Conclusions The expression level of Gli2 is high in giant cell tumor of bone, and Gli2 may be involved in recurrence,metastasis and malignant transformation. Gli2 may effect the osteolytic process of giant cell tumor of bone by the regulation mechanism of Gli2-PTHrP-RANKL pathway.