[Expression of MiRNA-21 in diffuse large B cell lymphoma and its significance].

MicroRNA-21 (miR-21) is considered to play a key role in many cellular processes, affecting tumorigenesis by inhibiting target gene expression. However, its role in diffuse large B-cell lymphoma (DLBCL) is still unclear, and there are no in depth studies on relationship between miR-21 and cellular phenotype. This study was aimed to investigated the expression and role of miR-21 in the regulation of cell biological behavior in DLBCL. The expressions of miR-21 in three DLBCL cell lines were detected by real-time quantitative reverse-transcription polymerase chain reaction (qRT-PCR). The possible roles of miR-21 in the biological and behavioral properties of DLBCL were explored by transfection of anti-miR-21 for miR-21 knockdown. In addition, PDCD4 and PTEN were assessed by luciferase reporter assay, qRT-PCR and Western blot. The results revealed that miR-21 expression was significantly upregulated in activated B-cell-like DLBCL cells as compared to germinal centre-like DLBCL cells. The inhibition of miR-21 could induce suppression of proliferation and invasion, as well as increase apoptosis in DLBCL. Moreover, knockdown of miR-21 increased the expressions of PDCD4 and PTEN at the protein level but not at the mRNA level. It is concluded the miR-21 can regulate proliferation, invasion, and apoptosis, so it has a potential therapeutic application in DLBCL.

Roles of E-cadherin (CDH1) genetic variations in cancer risk: a meta-analysis.

E-Cadherin (CDH1) genetic variations may be involved in invasion and metastasis of various cancers by altering gene transcriptional activity of epithelial cells. However, published studies on the association of CDH1 gene polymorphisms and cancer risk remain contradictory, owing to differences in living habits and genetic backgrounds. To derive a more better and comprehensive conclusion, the present meta-analysis was performed including 57 eligible studies of the association between polymorphisms of CDH1 gene promoter -160 C>A, -347 G>GA and 3'-UTR +54 C>T and cancer risk. Results showed that these three polymorphisms of CDH1 were significantly associated with cancer risk. For -160 C>A polymorphism, -160A allele carriers (CA and CA+AA) had an increased risk of cancer compared with the homozygotes (CC), and the similar result was discovered for the -160A allele in the overall analyses. In the subgroup analyses, obvious elevated risk was found with -160A allele carriers (AA, CA, CA+AA and A allele) for prostate cancer, while a decreased colorectal cancer risk was shown with the AA genotype. For the -347 G>GA polymorphism, the GAGA genotype was associated with increased cancer risk in the overall analysis with homozygous and recessive models. In addition, results of subgroup analysis indicated that the elevated risks were observed in colorectal cancer and Asian descendants. For +54 C>T polymorphism, a decreased risk of cancer was found in heterozygous, dominant and allele models. Moreover, +54T allele carriers (CT, CT+TT genotype and T allele) showed a potential protective factor in gastric cancer and Asian descendants.

Gene therapy for colorectal cancer by an oncolytic adenovirus that targets loss of the insulin-like growth factor 2 imprinting system.

BACKGROUND: Colorectal cancer is one of the most common malignant tumors worldwide. Loss of imprinting (LOI) of the insulin-like growth factor 2 (IGF2) gene is an epigenetic abnormality observed in human colorectal neoplasms. Our aim was to investigate the feasibility of using the IGF2 imprinting system for targeted gene therapy of colorectal cancer. RESULTS: We constructed a novel oncolytic adenovirus, Ad315-E1A, and a replication-deficient recombinant adenovirus, Ad315-EGFP, driven by the IGF2 imprinting system by inserting the H19 promoter, CCCTC binding factor, enhancer, human adenovirus early region 1A (E1A) and enhanced green fluorescent protein (EGFP) reporter gene into a pDC-315 shuttle plasmid. Cell lines with IGF2 LOI (HCT-8 and HT-29), which were infected with Ad315-EGFP, produced EGFP. However, no EGFP was produced in cell lines with maintenance of imprinting (HCT116 and GES-1). We found that Ad315-E1A significantly decreased cell viability and induced apoptosis only in LOI cell lines in vitro. In addition, mice bearing HCT-8-xenografted tumors, which received intratumoral administration of the oncolytic adenovirus, showed significantly reduced tumor growth and enhanced survival. CONCLUSIONS: Our recombinant oncolytic virus targeting the IGF2 LOI system inhibits LOI cell growth in vitro and in vivo, and provides a novel approach for targeted gene therapy.

[Detection of Hepcidin in transfusion dependent myelodysplastic syndrome patients and its clinical significance].

OBJECTIVE: To explore the application value of detection of Hepcidin together with indicator of iron overload on clinical diagnosis and treatment of MDS with iron overload by measuring Hepcidin and iron load indices of transfusion dependent myelodysplastic syndrome (MDS) patients. METHODS: Enzyme-linked immunosorbent assay (ELISA), radioimmunoassay and colorimetry were used to determine the Hepcidin, serum ferritin (SF) and serum iron (SI) levels of 106 serum samples from 68 cases of transfusion dependent MDS patients, 30 serum samples of MDS patients without transfusion and 60 serum samples of controls. RESULTS: For MDS group, Hepcidin level in blood transfusion < 9 U subgroup was significantly higher than that in control group \[(583 ± 50) µg/L vs (175 ± 35) µg/L\] and there was a strong positive correlation between Hepcidin levels and SF (r = 0.976), but no correlation between Hepcidin and SI (r = 0.284); Both Hepcidin and SF level in transfusion 9 ∼ 24 U subgroup was significantly higher than those in control group \[(665 ± 80) µg/L vs (175 ± 35) µg/L; (1445 ± 275) µg/L vs (112 ± 26)µg/L\]; whereas for SI level, there was no difference between transfusion 9 ∼ 24 U subgroup and the control group. Hepcidin did not correlate with SF or SI; For blood transfusion > 24 U group, all of Hepcidin, SF and SI levels were higher than those in control groups \[(703 ± 64) µg/L vs (175 ± 35) µg/L; (2587 ± 352) µg/L vs (112 ± 26)µg/L; (20 ± 4) µg/L vs (14 ± 4) µmol/L\], Hepcidin negatively correlated with SF and SI (r = -0.536; r = -0.456). Hepcidin levels of RARS patients were significantly lower than RAEB patients \[(260 ± 40) µg/L vs (442 ± 51) µg/L\], and there was no significant difference between RARS group and control group regardless of the number of blood transfusion. CONCLUSION: Both Hepcidin and SF levels in MDS patients regardless of transfusion dependent or not, or the number of blood transfused were higher than those of normal controls, the increase of Hepcidin can not synchronize with the increase of SF level due to the increased blood transfusion, when blood transfusion > 24 U, Hepcidin level showed a negative relationship with SF and SI, reflecting the decreased ability of Hepcidin to inhibit body iron absorption during the increase of blood transfusion, which finally would lead to iron overload. We can predict the occurrence of iron overload in transfusion dependent MDS patients by dynamic monitoring concentration of Hepcidin.

Identification of SSR markers using soybean (Glycine max) ESTs from globular stage embryos

Microsatellites, or simple sequence repeats (SSRs), in expressed sequence tags (ESTs) provide an opportunity for low cost SSR development. We looked for EST-SSRs in 403,511 ESTs (generated by 454 sequencing and representing 70,654 contigs and 52,082 singletons) from soybean globular stage embryos. Among 122,736 unique ESTs, 3,729 contained one or more SSRs. In total, 3,989 SSRs were identified including 304 mono, 1,374 di, 2,208 tri, 70 tetra, 13 penta and 20 hexanucleotide SSRs. Thirty three EST-SSRs were selected for primer design and polymorphism analysis using twenty soybean cultivars and one wild-type soybean. Successful amplification was obtained using 21 of these primer pairs, 11 of which detected polymorphisms in these soybean cultivars. These results demonstrated that 454 high throughput sequencing is a powerful tool for molecular marker development. From the 3,989 identified SSRs we expect to obtain a large number of makers with polymorphism among different soybean cultivars, which would be useful for analysis of genetic diversity and maker assisted selection in the soybean breeding programs.

EST sequencing and SSR marker development from cultivated peanut (Arachis hypogaea L)

Making use of the gene resources of wild type peanuts is a way to increase the genetic diversity of the cultivars. Marker assisted selection (MAS) could shorten the process of inter-specific hybridization and provide a possible way to remove the undesirable traits. However, the limited number of molecular markers available in peanut retarded its MAS process. We started a peanut ESTs (Expressed Sequence Tags) project aiming at cloning genes with agronomic importance and developing molecular markers. In this study we found 610 ESTs that contained one or more SSRs from 12,000 peanut ESTs. The most abundant SSRs in peanut are trinucleotides (66.3 percent) SSRs and followed by dinucleotide (28.8 percent) SSRs. AG/TC (10.7 percent) repeat was the most abundant and followed by CT/GA (9.0 percent), CTT/GAA (7.4 percent), and AAG/TTC (7.3 percent) repeats. Ninety-four SSR containing ESTs were randomly selected for primer design and synthesis, of which 33 pairs could generate good amplification and were used for polymorphism assessment. Results showed that polymorphism was very low in cultivars, while high level of polymorphism was revealed in wild type peanuts.

[Effect of decitabine combined with Trichostatin A on MDS cell line SKM-1 in vitro].

The study was purposed to explore the effect and mechanisms of decitabine and/or Trichostatin A (TSA) on SKM-1 cells in vitro. The effect of decitabine and/or TSA on proliferation of SKM-1cells was analyzed with trypan blue exclusion; the differentiation of SKM-1 cells was detected by nitro-blue tetrazolium (NBT) reduction and flow cytometry; the apoptosis of cells was measured by Annexin V-FITC; the mRNA expression of Fas, survivin and P15(INK4B) in cells treated with decitabine and/or TSA was evaluated by RT-PCR. The results showed that decitabine and/or TSA were capable of inhibiting SKM-1 cell growth and promoting cell differentiation; they stimulated the expression of CD14 and CD11b and inhibited HLA-DR expression; meanwhile and decitabine or/and TSA could induce cell apoptosis, up-regulate mRNA expression of Fas and P15(INK4B), and down-regulate survivin mRNA expression. It is concluded that decitabine can induce apoptosis/differentiation of SKM-1 cells, whose mechanisms may related to the expression of Fas, survivin and P15(INK4B). Decitabine has the synergistic effect with TSA.

[Cytogenetic and clinical study of myeloid leukemia].

OBJECTIVE: To explore the clinical cytogenetic features and prognosis of myeloid leukemia patients. METHODS: Bone marrow direct method and/or 24h culture without phytohaemagglutimin(PHA) were used to prepare the chromosomes and karyotype analysis was performed with R-banding and G-banding techniques. RESULTS: Among 420 patients with acute myeloid leukemia (AML), 223 cases were found to exhibit clonal chromosome abnormalities, accounted for 53.1%. t(8; 21), t(15; 17), inv(16)and del(11) were specifically associated with M2b, M3, M4Eo and M5 respectively. Out of 158 patients with chronic myeloid leukemia (CML), 96.8% (153/158) were found to exhibit clonal chromosome abnormalities. T(9;22) was specifically associated with CML and some cases of M0, M1 and M2. In these myeloid leukemia cases, there were 18 cases (AML 13 cases, CML 15 cases) without clonal chromosome abnormalities, accounted for 3.1% (18/578) and this phenomenon agreed with the diagnose of clinical signs, marrow morphology and immunology incompletely. CONCLUSION: Karyotype analysis was not only helpful to the diagnose and differential diagnose of myeloid leukemia, but also an important standard of the remission, relapse and therapeutic effect of myeloid leukemia. Chromosome analysis can be made exactly with the probe and FISH technique on the basic of chromosome karyotype analysis.