Expression of dead box 1 gene in neuroblastoma

Objective To detect the expression of dead box 1 (DDX1) gene in tumor tissue and pericarcinomatous tissue of clinical neuroblastoma(NB) samples, and explore the relationship between DDX1 and NB. Methods Five cases of pathological specimens in children with NB were chosen from Department of Pathology, the First Affi-liated Hospital of Xinxiang Medical University between January 2012 and December 2014.In the 5 cases, 3 cases were male, 2 cases were female, the age of 1-5 years old, average age (2.1±1.6) years.The NB tissue and pericarcinomatous tissue (pericarcinomatous tissue was normal tissue which was at least 2 cm from the tumor tissue) of 5 children were collected and fixed in 40 g/L formaldehyde solution.Then with the conventional dehydration, embedding, sectioning, dewaxing, hydration, antigen repair, add primary antibodies, secondary antibodies, diaminobenzine chromogenic.The expressions of DDX1 in tumor tissue and pericarcinomatous were observed with light microscopy and with semi-quantitative analysis.(1)Staining degree: no staining with 0 score; light staining with 1 score; medium staining with 2 scores; deeply staining with 3 scores.(2)Positive cells proportion: positive cells proportion 61% with 3 scores.Final scores were a half of the sum of staining degree score and positive cells proportion score, final score within 0-1.0 with"-", 1.1-2.0 with"+", 2.1-3.0 with"+ +", 3.1-5.0 with"+ + +". Results DDX1 were expressed in NB and pericarcinomatous tissues, but visible DDX1 positive staining number more and deeper in NB, DDX1 positive staining number less and light in pericarcinomatous tissues.Five cases of pericarcinomatous tissues immunohistochemical semi-quantitative score were negative and final scores were 1.0 score or less, the mean value was 0.5 score.NB immunohistochemical semi-quantitative score were"+"or"+ +"and final scores were 1.5 score or higher, the mean value was 1.8 scores, the expressions of DDX1 were significantly higher in NB than the pericarcinomatous tissues. Conclusions DDX1 is highly expressed in NB, which may contribute to the development of NB.This suggest DDX1 may serve as an oncogene and play a catalytic role in the development of NB, which provides a clinical evidence for the follow-up study. Key words: Neuroblastoma; DDX1 gene; Immunohistochemistry