The cancer-related transcription factor Runx2 combined with osteopontin: a novel prognostic biomarker in resected osteosarcoma.

PURPOSE

Osteosarcoma is the most common primary bone cancer in children and young adults. Recent experimental evidence has indicated that Runx2/OPN axis play important roles in the metastasis of osteosarcoma cells. The present study aimed to explore their relationship and prognostic significance in surgically resected osteosarcoma.

METHODS

The expression of runt-related transcription factor2(Runx2) and osteopontin (OPN) in clinical specimens from 105 osteosarcoma patients were detected by immunohistochemistry. The correlations between Runx2, OPN, and clinicopathologic data were analyzed by Chi-square (χ) tests. The prognostic values were determined by univariate and multivariate survival analysis. The accuracy of oncologic outcome prediction was evaluated by receiver-operating characteristics curves.

RESULTS

The results showed there is a significant positive correlation between Runx2 and OPN expression at protein levels (P = 0.015). Runx2 and OPN were both independent predictors for overall survival and metastasis-free survival. When Runx2 and OPN were taken into consideration together, the predictive range was extended and the sensitivity was improved, and more significant and better biomarkers for osteosarcoma metastasis and survival.

CONCLUSIONS

These results suggest that a combined Runx2/OPN expression could be a valuable independent predictor of tumor metastasis and survival in osteosarcoma patients.