Biological analysis of chronic lymphocytic leukemia: integration of mRNA and microRNA expression profiles

Chronic lymphocytic leukemia (CLL) is a disease that involves progressive accumulation of nonfunctioning lymphocytes and has a low cure rate. There is an urgent requirement to determine the molecular mechanism underlying this disease in order to improve the early diagnosis and treatment of CLL. In this study, genes differentially expressed between CLL samples and age-matched controls were identified using microRNA (miRNA) and mRNA expression profiles. Differentially expressed (DE) miRNA targets were predicted by combining five algorithms. Common genes were obtained on overlapping the DE mRNA and DE miRNA targets. Then, network and module analyses were performed. A total of 239 miRNA targets were predicted and 357 DE mRNAs were obtained. On intersecting miRNA targets and DE mRNAs, 33 common genes were obtained. The protein-protein interaction network and module analysis identified several crucial genes and modules that might be associated with the development of CLL. These DE mRNAs were significantly enriched in the hematopoietic cell lineage (P = 2.58E-4), mitogen-activated protein kinase signaling pathway (P = 0.0025), and leukocyte transendothelial migration pathway (P = 0.0026). Thus, we conducted biological analysis on integration of DE mRNAs and DE miRNAs in CLL, determined gene expression patterns, and screened out several important genes that might be related to CLL.