The hedgehog antagonist HHIP as a favorable prognosticator in glioblastoma

Inactivation of hedgehog-interacting protein (HHIP) and overexpression of Gli1 play vital roles in the development of diverse human cancers. The aim of this study is to examine the association of HHIP and Gli1 with the clinicopathologic features and prognosis of patients with glioblastoma (GBM). The expression of HHIP and Gli1 in 103 patients with GBM and 32 control patients was investigated by immunohistochemistry. Statistical analysis was utilized to evaluate the association of HHIP as well as Gli1 with clinicopathological characteristics and prognosis of patients. HHIP and Gli1 were dysregulated in GBM. Spearman's rank analysis showed that HHIP and Gli1 had an inverse correlation (r = -0.386, P = 0.000). Expression of HHIP was significantly correlated with age (P = 0.000), gender (P = 0.003), seizure (P = 0.013), resection degree (P = 0.033), adjuvant treatment (P = 0.030), and O(6)-methylguanine-DNA methyltransferase (MGMT) methylation (P = 0.021), while Gli1 expression was significantly correlated with age (P = 0.002), gender (P = 0.033), Karnofsky performance status (KPS) score (P = 0.028), resection degree (P = 0.000), adjuvant treatment (P = 0.014), and MGMT methylation (P = 0.030). Kaplan-Meier method showed that patients with low Gli1 expression had longer overall survival (OS) than those with high Gli1 expression (P = 0.000) and the OS of the patients with HHIP-positive GBM was significantly longer than that of the patients with HHIP-negative GBM (P = 0.000). Univariate and multivariate analyses confirmed that HHIP expression and Gli1 expression were independent prognostic factors. Our data suggested that expression of HHIP could be considered as significant prognostic marker for patients with GBM.