Gene exrpression profiling of childhood adrenocortical tumors

Pediatric adrenocortical tumors (ACT) are rare and often fatal malignancies; little is known regarding their etiology and biology. To provide additional insight into the nature of ACT, we determined the gene expression profiles of 24 pediatric tumors (five adenomas, 18 carcinomas, and one undetermined) and seven normal adrenal glands. Distinct patterns of gene expression, validated by quantitative real-time PCR and Western blot analysis, were identified that distinguish normal adrenal cortex from tumor. Differences in gene expression were also identified between adrenocortical adenomas and carcinomas. In addition, pediatric adrenocortical carcinomas were found to share similar patterns of gene expression when compared with those published for adult ACT. This study represents the first microarray analysis of childhood ACT. Our findings lay the groundwork for establishing gene expression profiles that may aid in the diagnosis and prognosis of pediatric ACT, and in the identification of signaling pathways that contribute to this disease. We used microarrays to explore the expression profiles differentially expressed in childhood adrenocortical tumors and in normal adrenal gland tissues. Pediatric adrenocortical adenoma and carcinoma patients were enrolled on the International Pediatric Adrenocortical Tumor Registry (IPACTR) and Bank protocol. Tumor specimens were harvested during surgery and snap frozen in liquid nitrogen to preserve tissue integrity. Data have been compiled for eight males and 15 females between 0 and 16 years of age. Table 1 (West et al, Cancer Research 67:601-608, 2007) summarizes the primary clinical information for each subject (excluding sample Unk1 with ACT of undetermined histology), including stage of the disease, tumor class, sex, age, relapse-free survival, and overall survival.