title: Role of podocalyxin in astrocytoma: Clinicopathological andin vitroevidence.
abstract: The present study examined the expression of podocalyxin (PODX) in surgically-resected astrocytomas, associated the levels of PODX expression with the clinicopathological characteristics and survival outcomes of astrocytoma and assessed how PODX affected the viability of astrocytoma cells following the administration of chemotherapeutic agents. The immunohistochemical analysis of 102 patient samples revealed that a high expression of PODX was significantly associated with high-grade astrocytomas (P<0.001) and a high Ki-67 labeling index (LI; P<0.001). A Kaplan-Meier survival analysis demonstrated that the high PODX expression group had significantly shorter disease-free survival (DFS) and overall survival (OS) rates compared with the low expression group (P<0.001). The multivariate analysis using the Cox's proportional hazards model revealed that a high expression of PODX, a high World Health Organization grade and a high Ki-67 LI were independent factors for shorter DFS and OS times. A subsequentin vitrostudy using SW1783 and U-87 human astrocytoma cell lines revealed that knocking down PODX decreased astrocytoma cell viability against temozolomide-induced apoptotic stress through the inhibition of the Akt survival signaling pathway. In conclusion, thein vivofindings indicated that a high expression of PODX is predictive of a poor survival outcome and, thus, may be used as a prognostic factor to predict the survival outcomes of astrocytoma patients. Thein vitrofindings indicated that PODX may promote astrocytoma cell viability against chemotherapeutic agent-induced apoptotic stress through the Akt pathway, indicating that PODX may be a novel target for overcoming chemoresistance in astrocytomas.
authors.affiliation: Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China.
authors.forename: Tianxiang
authors.initials: T
authors.lastname: Huang
authors.forename: Xin
authors.initials: X
authors.lastname: Jin
authors.forename: Lei
authors.initials: L
authors.lastname: He
authors.forename: Mingyu
authors.initials: M
authors.lastname: Zhang
authors.forename: Jun
authors.initials: J
authors.lastname: Wu
authors.forename: Yanjin
authors.initials: Y
authors.lastname: Wang
authors.forename: Jiasheng
authors.initials: J
authors.lastname: Fang
keywords: Akt; Ki-67; astrocytoma; cell survival; disease-free survival; overall survival; podocalyxin; temozolomide