BACKGROUND: The purpose of the current study was to investigate a hospital series of 986 cases of primary pediatric brain tumors in Taiwan.METHODS: The authors reviewed the database of primary pediatric brain tumors in patients < 18 years of age collected in Taipei Veterans General Hospital (Taipei VGH) from 1975 to May 2004. Age and gender distribution, location, and classification of brain tumors were analyzed. Intracranial tumors with diagnostic imaging were included. Nontumoral lesions, cysts, and vascular malformations were excluded.RESULTS: The mean age of these 986 patients was 7.8 years, and the male to female ratio was 1.4:1. Supratentorial (including pineal–quadrigeminal) located tumors (58.3%) was predominant to infratentorial tumors (41.1%). In these series, 886 patients had either histologic diagnosis (842 patients) or clinical diagnosis (44 patients). The most common 5 categories of tumors were astrocytic tumors (31.1%), germ cell tumors (14.0%), medulloblastomas (13.3%), craniopharyngiomas (8.3%), and ependymal tumors (5.8%). Atypical teratoid/rhabdoid tumors (AT/RTs), a rare but highly malignant tumor, were 2.1%. The high incidence of primary intracranial germ cell tumors correlated with reported series from Japan and Korea. For the remaining 100 patients without diagnostic classifications, the majority were most likely astrocytic tumors in brain stem.CONCLUSIONS: The authors analyzed a large hospital series of primary brain tumors in children. Both histologically verified and unverified tumors were recruited to avoid selective bias. Although it was not a study of a population‐based brain tumor registry, it could still be representative of primary pediatric brain tumors in Taiwan. Cancer 2005. © 2005 American Cancer Society.

Exome sequencing (exome-seq) has aided in the discovery of a huge amount of mutations in cancers, yet challenges remain in converting oncogenomics data into information that is interpretable and accessible for clinical care. We constructed DriverDB (http://ngs.ym.edu.tw/driverdb/), a database which incorporates 6079 cases of exome-seq data, annotation databases (such as dbSNP, 1000 Genome and Cosmic) and published bioinformatics algorithms dedicated to driver gene/mutation identification. We provide two points of view, ‘Cancer’ and ‘Gene’, to help researchers to visualize the relationships between cancers and driver genes/mutations. The ‘Cancer’ section summarizes the calculated results of driver genes by eight computational methods for a specific cancer type/dataset and provides three levels of biological interpretation for realization of the relationships between driver genes. The ‘Gene’ section is designed to visualize the mutation information of a driver gene in five different aspects. Moreover, a ‘Meta-Analysis’ function is provided so researchers may identify driver genes in customer-defined samples. The novel driver genes/mutations identified hold potential for both basic research and biotech applications.

Atypical teratoid/rhabdoid tumor (AT/RT) is an extremely malignant neoplasm in the central nervous system (CNS) which occurs in infancy and childhood. Recent studies suggested that CD133 could be considered a marker for brain cancer stem-like cells (CSCs). However, the role of CD133 in AT/RT has never been investigated. Herein we report the isolation of CD133-positive cells (CD133⁺), found to have the potential to differentiate into three germ layer tissues, from tissues of nine AT/RT patients. The migration/invasion/malignancy and radioresistant capabilities of CD133⁺ were significantly augmented when compared to CD133⁻. The clinical data showed that the amount of CD133⁺ in AT/RTs correlated positively with the degree of resistance to radiation therapy. Using cDNA microarray analysis, the genotoxic–response profiles of CD133⁺ and CD133⁻ irradiated with 10 Gy ionizing radiation (IR) were analyzed 0.5, 2, 6, 12 and 24 h post-IR. We then validated these microarray data and showed increased phosphorylation after IR of p-ATM, p-RAD17, and p-CHX2 as well as increased expression of BCL-2 protein in CD133⁺ compared to CD133⁻. Furthermore, we found that CD133⁺ can effectively resist IR with cisplatin- and/or TRAIL-induced apoptosis. Immunohistochemical analysis confirmed the up-regulated expression of p-ATM and BCL-2 proteins in IR-treated CD133⁺ xenotransgrafts in SCID mice but not in IR-treated CD133⁻. Importantly, the effect of IR in CD133⁺ transplanted mice can be significantly improved by a combination of BCL-2 siRNA with debromohymenialdisine, an inhibitor of checkpoint kinases. In sum, this is the first report indicating that CD133⁺ AT/RT cells demonstrate the characteristics of CSCs. The IR-resistant and anti-apoptotic properties in CD133⁺ may reflect the clinical refractory malignancy of AT/RTs and thus the activated p-ATM pathway and BCL-2 expression in CD133⁺ could be possible targets to improve future treatment of deadly diseases like AT/RT.