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The T-box gene family refers to a group of transcription factors that share a highly conserved, sequence-specific DNA-binding domain (T-box) containing around 180-amino acids. According to HUGO gene nomenclature committee (HGNC), there are 18 T-box family members. These T-box genes have been implicated essential roles during embryogenesis and cardiac development, given their specific expression pattern in developing mammalian heart for several T-box genes, including TBX5 . TBX5 is consisted of three transcriptional variants which cover 9 exons and encode two distinct isoforms that differ in N-terminus. TBX5 is probably the most frequently studied T-box gene over the past decade due to the typical cardiac defects observed in Holt-Oram syndrome (HOS), which is caused by TBX5 mutation. Most of the mutations are within exons 3-7 where locate sequence coding for the T-box domain. Notably, a variety of cardiac defects, as well as abnormalities in limb and other organs have been seen in HOS syndrome with different kinds of TBX5 mutations, suggesting a heterogeneous disease mechanism. We have performed a meta-analysis of TBX5 and found a significant correlation between its single nucleotide polymorphism (SNP) rs3825214 (A to G), and risk of atrial fibrillation and its subtypes, supporting TBX5 as a master transcription factor for cardiac development. In addition, bioinformatics analysis of this SNP identified several TFs that may be affected for their binding affinity with TBX5. Identification and characterization of more TBX5 mutations and SNPs hold promise for therapeutic strategy targeting TBX5 associated developmental abnormalities and diseases.

Runx2, a member of the Runt domain family, is a well-known master transcription factor for osteoblast differentiation. Runx2 has also been shown to play essential roles during chondrocyte hypertrophy, an important late stage of endochondral ossification linking both bone and cartilage development. To identify the co-factors that may interact with Runx2 together to regulate this critical process, we have performed yeast two-hybrid (Y2H) screening using Runx2 as a bait to screen a cDNA library of hypertrophic chondrocytes. The bait expressing cassette was constructed by fusing Runx2 with the pGBKT7 vector containing the Gal4 DNA binding domain (BD). The Mate & Plate libraries were constructed using pGADT7-Rec and cDNAs derived from hypertrophic chondrocytes enriched limb tissues or hypertrophic MCT cells. After co-transformation of pGBKT7-Runx2 and the cDNA libraries, colonies that grew in nutrition deficient medium were selected and subjected to PCR and sequencing analysis. We successfully identified more than 30 candidate genes, including Lectin-1 (Lgals1), Col1a2, Edf1 and Timp-2. We have performed literature review and bioinformatics analysis of these genes using GenePaint. Most of them show ubiquitous expression with Lgals1 show enhanced expression in hypertrophic chondrocytes. We further performed preliminary expression analysis by quantitative PCR and detected differential expression of these candidate genes in proliferative and hypertrophic MCT cells, with Timp-2 significantly (around 3-fold) and Lgals1 moderately (around 1.5 fold) upregulated in hypertrophic MCT cells. Our results suggest that, candidate gene Timp-2 is very likely to interact with Runx2 and together to play essential function during cartilage development, and possibly its homeostasis.

Objective: Previous study suggested adiponectin receptor 2 (ADIPOR2) genetic polymorphisms were associated with the risk of ischemic stroke. However, the relation between adiponectin receptor 1 (ADIPOR1) gene polymorphism and stroke remains unclear., Methods: In the present study, we utilized the polymerase chain reaction-sequencing method to detect rs2275737 and s1342387 genotypes of ADIPOR1 gene in 300 cases of ischemic stroke patients and 300 age- and sex- matched healthy controls., Results: For rs2275737, we found A allele carriers have increased risk to ischemic stroke (OR=2.570, 95% CI: 1.999-3.305); also, we found rs1342387 A allele was associated with the risk for stroke (OR=1.351, 95% CI: 1.074-1.699). After adjusted for confounders such as hypertension, diabetes, and smoking, we found the association remains significant., Conclusion: ADIPOR1 genetic polymorphism may increase the risk of ischemic stroke.

This study was aimed to investigate the effects of arsenic trioxide (As2O3) combined with TPA on cell cycle, cell differentiation and apoptosis of K562 cell line, and their possible mechanisms. K562 cells were treated with 200 nmol/L TPA, 2 µmol/L As2O3 alone and 200 nmol/L TPA combined with 2 µmol/L As2O3. The proliferative inhibition rates were determined with CCK-8. Annexin V and agarose gel electrophoresis were adopted to detect apoptosis. Colony formation test was used to determine the colony-formation efficiency. Flow cytometry was used to detect the cell differentiation and cell cycle changes. Western blot was employed to detect the expression of P38 and p-P38 proteins. The results showed that combination treatment had synergistic effects on the proliferative inhibition and apoptosis, which were much higher than those treated alone. As2O3 could decrease the colony formation ability of K562 cells. The cells treated with both TPA and As2O3 expressed far more CD11b antigens compared with cells exposed to As2O3 alone. K562 cells treated with TPA were arrested in G1 phase compared with the control group, As2O3 increased the percentage of K562 cells in the G2 phase. The combination treatment increased the expression of p-P38 of K562 cells compared with the cells exposed As2O3 alone. It is concluded that TPA can enhance the effect of As2O3 on inducing apoptosis and adjusting cell cycle , which will expect to provide a new therapeutic program.

Objective: To study melanoma cell fusion and find a highly efficient fusion method for tumor cells., Methods: Melanoma cells were labeled with green fluorescent protein and red fluorescent protein, respectively, and fused by a modified phytohaemagglutinin (PHA)-ECM830 fusion method. Melanoma fusion cells were selected by the fluorescence activated cell sorting. DNA content was determined by propidium iodide staining., Results: Melanoma cells were labeled with green fluorescent protein and red fluorescent protein markers and successfully fused through PHA-ECM830 fusion method. The fusion efficiency (7.18%) was much higher compared with ECM830 electricfusion method (0.50%). Melanoma fusion cells were successfully obtained by the fluorescence activated cell sorting.DNA content was doubled in melanoma fusion cells compared to B16-F10 melanoma cells. The proliferation rate of melanoma fusion cells was significantly decreased in vitro and in vivo., Conclusions: We successfully obtained the melanoma fusion cells by the improved PHA-ECM830 fusion method. The proliferation rate of melanoma fusion cells dramatically decreases.

Objective: To investigate the efficacy, adverse events and long-term survival of cyclophosphamide, vindesine, cytarabine, dexamethasone and bleomycin (COAD-B) regimen for relapsed and refractory non-Hodgkin lymphoma (NHL)., Methods: Eighty six patients diagnosed with relapsed or refractory NHL were included in our study from January 2007 to January 2013. The chemotherapy regimen was COAD-B, the therapeutic efficacy was evaluated every 2 courses. Once the stable disease (SD) or progress of the disease (PD) achieved, the patients would switch to other second-line regimens., Results: The overall response rate (ORR) was 67.4%, median remission duration was 13 months (3-51 months); 1-,2- and 4-year overall survival (OS) rates were 75.4%, 56.8% and 40.0%, respectively; 1-, 2- and 4-year progression-free survival (PFS) rates were 50.3%, 39.4% and 27.5%, respectively. The main adverse reaction of patients was myelosuppression. The response to chemotherapy and long- term survival of the relapsed patients were significantly better than that of the refractory ones, and the difference had statistical significance., Conclusion: COAD-B could be the salvage regimen for relapsed and refractory NHL.

This study was aimed to evaluate the frequencies and prognostic significance of the nucleophosmin 1 (NPM1) mutation, the fms-like tyrosine kinase 3 (FLT3) mutation and c-KIT mutation in acute myeloid leukemia (AML) and to explore their relevance to clinical characteristics, cytogenetics and survival. Genomic DNA from 78 newly diagnosed AML from August 2010 to October 2012 was screened by PCR and sequencing or capillary electrophoresis (CE) for NPM1, FLT3 and c-KIT mutations. The results showed that the incidence of NPM1 mutation was 14.1% in AML patients and 26.7% in normal karyotype AML patients. NPM1 mutant cases were significantly associated with old age (P < 0.05), high peripheral white cell count and platelet counts (P < 0.05) and low expression of CD34 (P < 0.05), but no statistic difference was found in sex, percentage of bone marrow blasts, Hb, expression of CD117 and HLA-DR, complete remission rate, overall survival and relapse rate (P > 0.05). The prevalences of FLT3-ITD and FLT3-TKD mutations were 11.5% (9/78) and 3.8% (3/78) respectively, and no one patient has both of the two mutations. Patients with FLT3-ITD mutation had higher white blood cell counts and percentage of in bone marrow blasts (P < 0.05), and lower overall survival (P < 0.05), more relative to normal karyotype (P < 0.05), while no statistic difference was found in sex, age, platelet count, Hb level, complete remission rate and relapse rate (P > 0.05). No statistic analysis was performed due to the cases of less FLT3-TKD mutation. C-KIT mutation accounts for 7.7% (6/78). Patients with C-KIT mutation had a higher percentage in abnormal karyotype (P < 0.05), and higher relapse rate (P < 0.05), and lower overall survival, whereas no statistic difference was found in sex, age, percentage of bone marrow blasts, peripheral blood cell count, complete remission rate (P > 0.05). It is concluded that the detection of NPM1, FLT3 and C-KIT mutations may contribute to guiding treatment and evaluating prognosis of patients with AML.

Objective: To study the effect of transforming growth factor-β activated kinase-1 (TAK1) gene silencing on the proliferation and apoptosis of Kasumi-1 cells induced by arsenic trioxide (As₂O₃)., Methods: Acute myeloid leukemia with t(8;21) cell line Kasumi-1 cells were treated with As₂O₃ or in combination with TAK1 siRNA interference technology. The experiment was divided into four groups: Kasumi-1 cells without any treatment, TAK1 specific siRNA transfection alone, Kasumi-1 cells treated with different concentration of As₂O₃, TAK1siRNA transfection combined with As₂O₃. CCK-8 was used to detect the cell viability. The expression of phosphorylated c-Jun N-terminal kinase (P-JNK) was determined by Western Blot. Cell apoptosis and growth were examined by morphological and colony formation assay., Results: After Kasumi-1 cells were treated with As₂O₃, the rate of cell inhibition was concentration-dependent, and the 50% inhibitory concentration was 3.5 μmol/L. The highest expression level of P-JNK appeared in 30 minutes after cells were treated with As₂O₃. The apoptosis rates of Kasumi-1 cells without any treatment, TAK1 siRNA interference alone group, As₂O₃ alone group and the combined group were (5.02 ± 1.13)%, (6.18 ± 0.28)%, (48.33 ± 2.70)% and (86.07 ± 2.21)%; colony formation rates were (73.83 ± 2.78)%, (76.03 ± 1.46)%, (55.07 ± 1.50)% and (22.20 ± 1.15)%; apoptosis rate of TAK1 siRNA group and the untreated group has no significant difference (P = 0.052); colony formation rate between TAk1 siRNA group and the untreated group has no significant difference (P = 0.179), but the difference in other groups was significant (P = 0.000)., Conclusion: Silencing the expression of TAK1 can enhance the anti-proliferative and pro-apoptotic effect of As₂O₃ on Kasumi-1 cells, and its mechanism may be through the TAK1 downstream JNK signal pathway.

Objective: To detect the changes of naive T cell level of thymic recent output at different stages of treatment in patients with diffuse large B-cell lymphoma (DLBCL), thereby to evaluate the relationship of thymic recent output function with prognosis and the impact of chemotherapy on the potential of immunological recovery., Methods: The levels of T-cell receptor rearrangement excision circles (TREC) in DNA of peripheral blood mononuclear cells (PBMNC) from 30 DLBCL patients were monitored before, during, until 3 months and 6 months after chemotherapy by real-time PCR (TaqMan), and TREC-level was detected according to the number of CD3 positive(CD3(+)) cells. Twelve normal individuals who matched in age were served as controls., Results: There was a dramatic reduction of TREC values in all DLBCL patients among which TREC values in germinal center B-cell-like-DLBCL (GCB-DLBCL) were higher than those in non-GCB-DLBCL, as compared with TREC values of normal individual in peripheral blood. The mean values of TREC were 0.91 ± 0.15/1000 PBMNCs and (1.22 ± 0.69)/1000 CD3(+) cells in GCB-DLBCL, (0.43 ± 0.29)/1000 PBMNCs and (0.64 ± 0.44)/1000 CD3(+) cells in non-GCB-DLBCL before chemotherapy. TREC values were significantly associated with lower international prognostic index (IPI) grade (r = -0.441, P = 0.015). TREC-level in DLBCL patients was further decreased after chemotherapy, and reached to the lowest level after the 6th cycle of chemotherapy, and during the corresponding period, the mean values of TREC were (0.63 ± 0.34)/1000 PBMNCs and (0.89 ± 0.65)/1000 CD3(+)cells in GCB-DLBCL, (0.19 ± 0.11)/1000 PBMNCs and (0.27 ± 0.25)/1000 CD3(+) cells in non-GCB-DLBCL. TREC-level began to rise obviously 3 months after the last cycle of chemotherapy in most of the DLBCL patients, and came close to normal level in five cases of patients 6 months after the last cycle of chemotherapy., Conclusions: Thymic recent output function was impaired severely in DLBCL patients. There was an important relationship between thymic recent output function before chemotherapy and prognosis, and chemotherapy had influenced the potential of immunological recovery.

Objective: To assess the frequencies and prognostic significance of the isocitrate dehydrogenase 1 and 2 (IDH1 and IDH2) mutations in acute myeloid leukemia (AML) and to explore their relevance to clinical, cytogenetic and molecular feature., Methods: Genomic DNA from 96 newly diagnosed AML patients from Sep. 2009 to Jan. 2011 was screened by RT-PCR and sequencing for IDH1 and 1DH2 mutation., Results: The prevalence of IDH1 (p. P127 and p. I130) and IDH2 mutations (p. R140) was 14.6% (14/ 96) and 2.17% (2/96) respectively. The IDH1 mutations of p. P127 and p. I130 were not reported so far in literature. Of 14 IDH1 mutation patients, 10 were with normal karyotype and the differences had statistical significance (P=0.021). Two patients with IDH2 mutation were also with normal karyotype. IDH2 mutations were in older patients at diagnosis. Patients with IDH mutation had higher white blood cell counts, lower platelet counts, expression of HLA-DR, CD34, CD33 and CD13, lower remission rate and higher relapse rate., Conclusion: IDH mutation is recurring genetic change in AML and indicates poor prognosis.