High expression of stathmin protein predicts a fulminant course in medulloblastoma

Abstract

Object Stathmin, an important cytosolic phosphoprotein, is involved in cell proliferation and motility. This study was performed to elucidate the role of stathmin in the progression of medulloblastoma. Methods The expression of stathmin protein was examined by immunohistochemical staining of tumor sections obtained in 17 consecutive patients with medulloblastoma who underwent resection between 1995 and 2005. Four patients were excluded because they were either lost to follow-up or underwent biopsy sampling only, leaving a total of 13 patients in the study. The stathmin expression was scored according to the immunoreactive fraction of tumor cells, and the level was correlated with various clinicopathological factors. Results The expression level of stathmin protein was ≤ 10% in 9 patients, 11–50% in 1, and > 50% in 3. No staining was seen in the tissues adjacent to the tumors. For comparison, the authors grouped the expression level of stathmin into high (> 50%) and low (≤ 50%). It was found that patients with high expression of stathmin had more frequent tumor dissemination at the time of resection or soon after total excision of the tumor (p = 0.0035), and hence experienced a fulminant course with lower patient survival (p < 0.0001), with an average survival period of 6.7 months (range 2–10 months). The expression level of stathmin did not correlate with patient age, sex, CSF cytological findings, use of adjuvant therapies, Ki 67 index, or risk classification of the tumors according to previously described categories in the literature. Conclusions High stathmin expression correlates with tumor dissemination, is an important prognostic factor of medulloblastoma, and may serve as a useful marker for more intensive adjuvant therapies.