Background & objective: Recent research had showed that tumor cell adhesion molecular CD44 and matrix metalloproteinases (MMP) were expressed strongly in many tumors, and was associated closely with invasion and metastasis of the tumors. Ki-67 was one of the proliferative markers, which indicated the growth rate of tumor cells. However, the relationship among these markers and the invasion, metastasis, and recurrence of osteosarcoma was unclear yet. In this research the authors studied the expression of standard-type CD44(CD44s), MMP-9, and Ki-67 in osteosarcoma, and their relation to the invasion, metastasis, and recurrence of the tumor.
Methods: Immunohistochemistry staining(SP method) was used to detect CD44s, MMP-9, and Ki-67 in cases of osteosarcoma. Bone benign disease or normal connective tissue were used as the control. The results were treated with semi-quantitative method and analyzed by using non-parameter rank sum test.
Results: The positive rates of CD44s, MMP-9, and Ki-67 in osteosarcoma were 71.0%, 75.8%, and 35.5%, respectively, which were significantly higher than that in control tissue. The positive rate of Ki-67 in recurrent osteosarcoma was 81.8%, which was significantly higher than that in primary tumor. CD44s and Ki-67 positive rates were 88.9% and 66.7% respectively in osteosarcoma with lung metastasis, which were both significantly higher than that in osteosarcoma without lung metastasis. In poorly differentiated osteosarcoma positive rates of CD44s and MMP-9 were 76.3% and 79.7%, respectively, which were significantly higher than that in well differentiated tumor. Spearman correlation analysis proved that the expression of CD44s, MMP-9, and Ki-67 had significant relation to another.
Conclusions: Increase of CD44s, MMP-9, and Ki-67 were involved in the growth and local invasion of osteosarcoma. The recurrence of osteosarcoma was associated with the proliferative rate of tumor cells. Whether there were early lung metastasis or not was affected by the amount of CD44s and the proliferative rate of the tumor cell. The poorer differentiation of osteosarcoma cells, the higher level of CD44s and MMP-9.