Expression of TNKS1 is correlated with pathologic grade and Wnt/β-catenin pathway in human astrocytomas

Astrocytoma is the most common neoplasm of the central nervous system, and its malignancy is closely related to activation of the Wnt/beta-catenin pathway. Accumulated evidence shows that tankyrase (INKS) is necessary for the Wnt/beta-catenin pathway, stabilizing beta-catenin, and that TNKS1, a major member of the INKS family, is involved in a wide range of human cancers. However, the expression of TNKS1 and the molecular relationship between TNKS1 and beta-catenin in human astrocytomas is largely unknown. In the present study, we investigated the expression of TNKS1 in human astrocytomas using reverse transcription-polymerase chain reaction, Western blot and immunohistochemistry. The mRNA and protein expression levels of TNKS1 in astrocytomas were significantly higher compared with the normal brain tissues. Significant association between TNKS1 upregulation and pathological grade of astrocytomas was also confirmed. In addition, beta-catenin immunostaining of the sampled tissues revealed a highly similar change to TNKS1. This study provides additional evidence for the involvement of TNKS1 gene and the Wnt/beta-catenin signaling pathway in the genesis and progression of astrocytoma. TNKS1 may have a key role in astrocytomas. (C) 2011 Elsevier Ltd. All rights reserved.