FAMLF is a target of miR-181b in Burkitt lymphoma.

Burkitt lymphoma (BL) is a highly malignant non-Hodgkin's lymphoma that is closely related to the abnormal expression of genes. Familial acute myelogenous leukemia related factor (FAMLF; GenBank accession No. EF413001.1) is a novel gene that was cloned by our research group, and miR-181b is located in the intron of the FAMLF gene. To verify the role of miR-181b and FAMLF in BL, RNAhybrid software was used to predict target site of miR-181b on FAMLF and real-time quantitative PCR (RQ-PCR) was used to detect expression of miR-181b and FAMLF in BL patients, Raji cells and unaffected individuals. miR-181b was then transfected into Raji and CA46 cell lines and FAMLF expression was examined by RQ-PCR and western blotting. Further, Raji cells viability and proliferation were detected by MTT and clone formation, and Raji cell cycle and apoptosis were detected by flow cytometry. The results showed that miR-181b can bind to bases 21-42 of the FAMLF 5' untranslated region (UTR), FAMLF was highly expressed and miR-181b was lowly expressed in BL patients compared with unaffected individuals. FAMLF expression was significantly and inversely correlated to miR-181b expression, and miR-181b negatively regulated FAMLF at posttranscriptional and translational levels. A dual-luciferase reporter gene assay identified that the 5' UTR of FAMLF mRNA contained putative binding sites for miR-181b. Down-regulation of FAMLF by miR-181b arrested cell cycle, inhibited cell viability and proliferation in a BL cell line model. Our findings explain a new mechanism of BL pathogenesis and may also have implications in the therapy of FAMLF-overexpressing BL.

Effect of CYP1A1 and GSTM1 genetic polymorphisms on bone tumor susceptibility.

Tumor gene polymorphisms are often associated with individual susceptibility to genetic diseases. Cytochrome P4501A1 (CYP1A1) and glutathione S-transferase mu 1 (GSTM1) gene polymorphisms are closely related to the susceptibility of the body to chemical carcinogens in the environment. Therefore, we explored the relationship between CYP1A1 and GSTM1 gene polymorphisms and susceptibility to bone tumors. Multiplex-polymerase chain reaction (PCR), allelic-specific PCR, and PCR-restriction fragment length polymorphism techniques were used to analyze CYP1A1 and GSTM1 gene polymorphisms in 52 bone tumor patients and 100 healthy subjects. The allelic variation frequency of the CYP1A1 gene at exon 7 (Ile 462 Val) in bone tumor patients was 0.462, which was significantly higher than that in the normal controls (0.223). The frequency of the absence of the GSTM1 homozygous genotype in the patients (0.65) was also markedly higher than that in the control group (0.41). Subjects with CYP1A1 Val/Val homozygous mutations and absence of the GSTM1 homozygous genotype were at markedly increased risk of developing bone tumors [ORs 4.15 (95%CI: 1.268-13.30) and 2.35 (95%CI: 1.15-4.85), respectively]. The OR for the combined effect of the CYP1A1 and GSTM1 gene polymorphisms was 8.55 (95%CI: 1.75-41.50). CYP1A1 and GSTM1 polymorphisms are genetic risk factors in patients with bone tumors, and the allelic variation of these genes increases the risk of bone tumor occurrence.

Screening and identification of the nucleic acid aptamers in nasopharyngeal carcinoma.

To screen the nucleic acid aptamers of the EB virus-positive nasopharyngeal carcinoma cells, we used SELEX technology and synthesized in vitro a 78-nucleotide random DNA library. We used normal nasopharyngeal epithelial cells and EB virus-positive low differentiated nasopharyngeal carcinoma cells as target to conduct 10 cycles of screening, cloning, sequencing, and identification of the aptamers. The fluorescence produced by the combination of the sub-library and the target cells gained intensity gradually with the increase in the number of screening cycles, indicating elevated binding capacity. The cluster analysis showed that the aptamers can be divided into three families, with two of the families having the common conserved sequence. In this study, by screening nucleic acid aptamers for affinity and specificity, we established an initial aptamer library for EB virus-positive nasopharyngeal carcinoma cells.