Meningiomas are the most common primary intracranial tumors. Surgical resection remains the treatment of choice for these tumors. However, a significant number of tumors are either not surgically accessible, recur, or become malignant, necessitating repeat surgery and sometimes radiation. Chemotherapy is rarely used and is generally not recognized as effective. Cancer/testis (CT) genes represent a unique class of genes, which are expressed by germ cells, normally silenced in somatic cells, but activated in various cancers. CT proteins can elicit spontaneous immune responses in cancer patients and this feature makes them attractive targets for immunotherapy-based approaches. We analyzed mRNA expression of 37 testis-restricted CT genes in a discovery set of 18 meningiomas by reverse transcription PCR. The overall frequency of expression of CT genes ranged from 5.6 to 27.8%. The most frequently expressed was NY-ESO-1, in 5 patients (27.8%). We subsequently analyzed NY-ESO-1 protein expression in a larger set of meningiomas by immunohistochemistry and found expression in 108/110 cases. In some cases NY-ESO-1 expression was diffuse and homogenous, but in most instances was heterogeneous. Importantly, NY-ESO-1 expression positively correlated with higher grade and patients presenting with higher levels of NY-ESO-1 staining had significantly worse disease-free and overall survival. We have also demonstrated that NY-ESO-1 expression may lead to humoral immune response in meningioma patients. Considering the limited treatment options for meningioma patients, the potential of NY-ESO-1-based immunotherapy should be explored.
- Received March 26, 2013.
- Revision received July 17, 2013.
- Accepted July 17, 2013.
- Copyright © 2013, American Association for Cancer Research.