Effect of miR-449a on radiosensitivity of pancreatic cancer cells / 中华放射肿瘤学杂志

Objective The purpose of this study is to investigate the effect of miR-449a on pancreatic cancer cells and the molecular mechanism. Methods The expression levels of miR-449a in pancreatic cancer cells treated or untreated with radiation was detected by qRT-PCR.High expression of miR-449a was achieved by transfecting miR-449a mimics into SW1990 cells. The cell growth,apoptosis and colony formation ability was assessed by MTT assay,flow cytometry and colony formation assay,respectively. The relationship of miR-449a and Cyclin D1 was determined by the TargetScan and dual luciferase reporter. Immunohistochemistry was used to examine protein levels of Cyclin D1 in pancreatic cancer and normal pancreas tissues. Si-Cyclin D1 was used to detecte the effect of Cyclin D1 on radiosensitivity of pancreatic cancer cells. Results The expression levels of miR-449a in pancreatic cancer cells with radiation treatment were decreased significantly. Mir-449a mimics increased the cell proliferation rates and apoptosis rates obviously,and decreased the colony formation ability in SW1990 cells treated with radiation. Results from the TargetScan and dual luciferase reporter showed that Cyclin D1 was the target of miR-449a. The positive staining rates of Cyclin D1 in pancreatic cancer tissue(85.7%,30/35)was higher than those in normal pancreas tissue(20%,2/10).Knockdown of Cyclin D1 enhanced the radiosensitivity of pancreatic cancer cells.Conclusion MiR-449a enhances the radiosensitivity of pancreatic cancer cells by targeting Cyclin D1.

Effect of brentuximab vedotin combined with chlormethine hydrochloride on the treatment of 6 patients with relapsed and refractory Hodgkin lymphoma / 中华血液学杂志

<p><b>OBJECTIVE</b>To observe the clinical efficacy and side effects of brentuximab vedotin (BV) plus chlormethine hydrochloride (CH) in patients with relapsed and refractory Hodgkin lymphoma (HL) after failure with BV alone.</p><p><b>METHODS</b>From March, 2014 to December, 2014, 6 patients who failed with BV monotherapy were enrolled in this study. The chemotherapy regimen consisted of BV (1.2-1.8 mg/kg, iv. gtt, d1) and CH (6 mg/m2, iv. gtt, d1) was given for 3 weeks as one course, and all patients received about 3-8 courses of chemotherapy, with an median of 4 courses. Clinical efficacy and adverse events were assessed and observed by radiographic examination and serological detection.</p><p><b>RESULTS</b>Among 6 patients, the overall response rate was 100% with 2 complete remission and 4 partial remission. The main adverse events were grade I (2 patients) and IV (2 patients) bone marrow depression, grade II (2 patients)gastrointestinal reaction, grade I (1 patient) increase of transaminase and myocardial enzyme and grade I (1 patient) mouth ulcers.</p><p><b>CONCLUSION</b>The combination of BV and CH in the treatment of relapsed and refractory HL after failure with BV alone was high effective and the toxicities were well tolerable.</p>

Application of multiplex nested RT- PCR assay for screening the fusion genes in acute myeloid leukemia and its clinical significance / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the clinical value of multiplex nested reverse transcription PCR (RT-nPCR) in screening acute myeloid leukemia(AML)fusion genes.</p><p><b>METHODS</b>A novel multiplex RT-nPCR assay was developed to detect 16 AML-related fusion genes (AML1-EVI1, AML1-ETO, AML1-MDS1, AML1-MTG16, MLL-AF9, MLL-AF6, MLL-AF10, MLL-ENL, MLL-MLL, PML-RARα, PLZFRARα, NPM1-RARα, CBFB-MYH11, DEK-CAN, SET-CAN and TLS-ERG) according to 2008 WHO classification of AML. The chromosome reciprocal translocations of 356 AML cases were detected by multiplex RT-nPCR and karyotyping. The positive samples were further confirmed by split- out PCR and FISH.</p><p><b>RESULTS</b>The fusion genes were detected in 172 patients with the positive detection rate of 48.31%(172/356), which was higher than that of karyotyping (31.46%) (χ²=70.314, P<0.01). Multiplex RT-nPCR is superior to karyotyping and FISH in identifying the rare, cryptic chromosome translocation (χ²=96.074, P<0.01).</p><p><b>CONCLUSION</b>The multiplex RT-nPCR used in this study can quickly, effectively and accurately screen the fusion genes in AML patients, which can provide important evidence for assessing diagnosis and treatment, and also provide necessary information for minimal residual disease (MRD) and prognosis.</p>

Application of attenuated salmonella in the gene treatment of tumor / 国际肿瘤学杂志

Salmonella is a kind of intracellular invasive facultative anaerobe,maintaining its antigenicity after being attenuated.Now,it has been widely used as a transporter of DNA vaccines.Salmonella carrying related antigen gene can inhibit multiple tumors,and salmonella carrying repair gene has a clear repair effect for the organism injury after chemoradiotherapy.

Egr-1 promoter regulating effect on granulocyte-macrophage colony-stimulating factor (GM-CSF) gene expression induced by doxorubicin and ionizing radiation / 中华放射医学与防护杂志

Objective To explore the regulating effects of Egr-1 promoter activated by ionizing radiation (IR) and doxorubicin (ADM) on the expression of granulocyte-macrophage colony-stimulating factor (GM-CSF) genes. Methods The human GM-CSF cDNA and enhanced green fluorescent protein (EGFP) cDNA were linked together with IRES(internal ribosome entry site) and then inserted into the expression vector pCIneo under control of the Egr-1 promoter(Egr-EG). The vector was transferred into human bone marrow stromal cell line HFCL by liposome transfection. And the cells were exposure to ADM and IR. The activity of EGFP in HFCL/EG cells were detected by FACS. The effect of N-acetylcysteine on the expression of EGFP following exposure to ADM and IR was examined. The amounts of GM-CSF in HFCL/EG after chemotherapy or radiation were measured with ELISA. The effects of GM-CSF in HFCL/EG cultural supernatants on expansion of CFU-GM derived from cord blood were also studied. RT-PCR analysis for the expression of GM-CSF mRNA in HFCL/EG after exposure to ADM or IR. Results The percentage of EGFP+ HFCL/EG cells exposed to ADM and IR was increased compared with non-treatment group (1.2 % and 15.2 % vs 18.2 %, t = 5.11, P < 0.01). The levels of secreted GM-CSF in HFCL/EG cells exposed to ADM and IR was increased (P < 0.01), but no difference between ADM group and IR group (P 0.05). The expression of EGFP by HFCL/EG treated with ADM and IR was significantly decreased by N-acetylcysteine. The effects of GM-CSF in HFCL/EG cultural supernatants on expansion of CFU-GM in ADM group and IR group were significantly higher than that in HFCL group and non-treatment group. However, The CFU-GM count of IR group was higher than that of ADM group. The expression of GM-CSF mRNA in HFCL/EG cells exposed to ADM and IR was significantly increased(t = 4.37, P < 0.01). Conclusions GM-CSF gene expression regulated by Egr-1 promoter induced by ADM and IR could help the recovery from hematopoietic injury.