PURPOSE: Long noncoding RNA 00703 (LINC00703) was found originating from a region downstream of Kruppel-like factor 6 (KLF6) gene, having 2 binding sites for miR-181a. Since KLF6 has been reported as a target of miR-181a in gastric cancer (GC), this study aims to investigate whether LINC00703 regulates the miR-181a/KLF6 axis and plays a functional role in GC pathogenesis.MATERIALS AND METHODS: GC tissues, cell lines, and nude mice were included in this study. RNA binding protein immunoprecipitation (RIP) and pull-down assays were used to evaluate interaction between LINC00703 and miR-181a. Quantitative real-time polymerase chain reaction and western blot were applied for analysis of gene expression at the transcriptional and protein levels. A nude xenograft mouse model was used to determine LINC00703 function in vivo.RESULTS: We revealed that LINC00703 competitively interacts with miR-181a to regulate KLF6. Overexpression of LINC00703 inhibited cell proliferation, migration/invasion, but promoted apoptosis in vitro, and arrested tumor growth in vivo. LINC00703 expression was found to be decreased in GC tissues, which was positively correlated with KLF6, but negatively with the miR-181a levels.CONCLUSIONS: LINC00703 may have an anti-cancer function via modulation of the miR-181a/KLF6 axis. This study also provides a new potential diagnostic marker and therapeutic target for GC treatment.
Animals ; Apoptosis ; Binding Sites ; Blotting, Western ; Cell Line ; Cell Proliferation ; Gene Expression ; Heterografts ; Immunoprecipitation ; In Vitro Techniques ; Mice ; Mice, Nude ; Real-Time Polymerase Chain Reaction ; RNA, Long Noncoding ; RNA-Binding Proteins ; Stomach Neoplasms

OBJECTIVETo investigate the methylation status of miR-378 promoter in chronic myeloid leukemia (CML) and to analyze its clinical significance.

METHODSThe unmethylation level of miR-378 gene promoter in bone marrow mononuclear cells of 25 healthy donors and 53 patients with CML was detected by using real-time quantitative methylation-specific PCR (RQ-MSP).

RESULTSThe hypomethylation of miR-378 gene promoter was found in 17/53 (32.1%) patients, but only in 1/25 (4.0%) of controls. The difference between the two groups was very statistically significant (P < 0.01). The frequency of miR-378 unmethylation in CML patients at chronic phase (CP), accelerated phase (AP) and blastic phase (BP) was 35.0% (14/40), 40.0% (2/5), and 12.5% (1/8), respectively. However, there were no significant differences in the unmethylation level of miR-378 among CML patients at different sexes, stages and karyotypes. No significant differences could be observed in age, white blood cell counts, platelet count, hemoglobin level and BCR/ABL1 transcript level (P > 0.05). CONCLUDSION: The miR-378 hypomethylation is a common molecular event in CML, especially at chronic or accelerated phases.

Bone Marrow Cells ; metabolism ; Case-Control Studies ; DNA Methylation ; Humans ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; genetics ; MicroRNAs ; metabolism ; Promoter Regions, Genetic

OBJECTIVETo study the methylation status of fragile histidine triad (FHIT) gene promoter in patients with myelodysplastic syndrome (MDS) and its clinical relevance.

METHODSMethylation-specific PCR (MSP) was used to detect FHIT promoter methylation in bone marrow samples from 54 MDS cases.

RESULTSHypermethylation of FHIT promoter was detected in 26 cases (48.1%). Association was not found between FHIT gene hypermethylation and sex, hematologic parameters and chromosomal abnormalities of MDS patients, but found between FHIT gene hypermethylation and age of the MDS cases. Although significant difference was not observed in the frequencies of FHIT gene hypermethylation among patients with refractory anemia/refractory anemia with ringed sideroblasts (RA/RAS) (1/6, 16.7%), refractory anemia/refractory anemia with ringed sideroblasts (RCMD) and refractory cytopenia with multilineage dysplasia with ringed blasts (RCMD-RS) (6/19, 31.6%), refractory anemia with excess blasts-1 (RAEB-1) (7/11, 63.6%), refractory anemia with excess blasts-2 (RAEB-2) (4/7, 57.1%) and refractory anemia with excess blasts in transformation/acute myeloid leukemia (RAEBt/AML) (8/11, 72.7%)(chi-square=8.417, P=0.077), it was observed in patients in early stages (RA/RAS and RCMD) (7/25, 28.0%), advanced stages (RAEB-1 and RAEB-2)(11/18, 61.1%) and RAEBt/AML (8/11, 72.7%) (chi-square=7.938, P=0.019). Furthermore, there was a positive correlation between the frequency of FHIT gene hypermethylation and different IPSS groups (chi-square=10.110, P=0.018).

CONCLUSIONFHIT gene hypermethylation might be one of the molecular events involved in the disease progression of MDS.

Acid Anhydride Hydrolases ; genetics ; Adolescent ; Adult ; Age Factors ; Aged ; Aged, 80 and over ; Base Sequence ; DNA Methylation ; Female ; Humans ; Male ; Middle Aged ; Molecular Sequence Data ; Myelodysplastic Syndromes ; classification ; genetics ; pathology ; Neoplasm Proteins ; genetics ; Polymerase Chain Reaction ; Promoter Regions, Genetic ; genetics