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Objective: To investigate the effect of silencing SET gene on the biological characteristics of acute promyelocytic leukemia NB4-R1 cells., Methods: The expression vector of pGCSIL containing SET-shRNA were transfected into 293T cells by using other packaging plasmids. The supernatant of the 293T cells was harvested for lentivirus. The SET-shRNA lentiviral vector was transfected into acute promyelocytic leukemia NB4-R1 cells and a stably transfected cell line was established. Real-time quantitative PCR and Western blot were used to assay the silencing efficiency on SET gene and the expression of PP2A. The cell cycle distribution was tested by flow cytometry., Results: The expression of SET in experimental group statistically decreased as compared with that of the control group. The expression of PP2A was obviously raised at the level of mRNA and protein. The percentage of NB4-R1 cells in G0/G1 phase significantly increased, while the percentage of cells in S phase significantly decreased., Conclusion: The silencing gene in acute promyelocytic leukemia NB4-R1 cells using SET-shRNA lentiviral vector can increase the expression of PP2A and interfere of the cell cycle in NB4-R1 cells. This study has laid a experimental base for targed therapy of patients with acute promyelocytic leukemia.

Objective: To explore the effect of RNA interference of human I2PP2A gene on the proliferation and apoptosis of retinoic acid-resistant human acute promyelocytic leukemia (APL) cell line NB4-R1., Methods: Designed and constructed a RNA interference lentiviral vector I2PP2A-shRNA which targeted against I2PP2A gene, then transfected it into NB4-R1 via polybrene mediation. The I2PP2A expression levels before and after transfection were detected by qRT-PCR and Western blot, respectively. Meanwhile, the proliferation and apoptosis rates of each group were determined by CCK-8 and flow cytometry assay. The protein expressions of caspase-8 and PARP were detected by Western blot., Results: Both qRT-PCR and Western blot data showed the I2PP2A expression level was significantly downregulated in the transfection group. The I2PP2A mRNA expression level decreased by (70.0 ± 9.6)% and (64.0 ± 6.2)% respectively, compared with blank control and negative control group, and the I2PP2A protein expression level showed a consistent trend. CCK-8 proliferation assay indicated the NB4-R1 cell proliferation rate in I2PP2A-shRNA transfection group significantly reduced compared to blank control group (P<0.05). Flow cytometry results showed that NB4-R1 apoptosis rate in I2PP2A-shRNA transfection group increased by (6.30 ± 0.67) times and (6.04 ± 0.56) times, respectively (P<0.01). After inhibition of I2PP2A, the total caspase-8 and total PARP expressions decreased by (44.0 ± 3.1)% and (57.0 ± 4.0)%, respectively; Meanwhile, the cleaved caspase-8 (p43) and cleaved PARP (p89) increased by (36.0 ± 2.5)% and (45.0 ± 4.8)%, respectively compared with blank control group (P<0.05)., Conclusion: I2PP2A gene silenced by RNA interference could inhibit the proliferation and promote the apoptosis of NB4-R1, which may be regulated through caspase-8-induced exogenous apoptosis pathway.

Objective: To investigate the expression level of SET gene in patients with acute myeloid leukemia (AML) and evaluate its significance., Methods: The expression level of SET gene in 141 de novo AML patients was determined by real time quantitative PCR (RQ-PCR), and its relationship with the clinical features and outcomes of these patients were analyzed., Results: SET gene transcript level was detected in 141 AML patients with the median expression level of 0.86(range 0.02-15.69). AML patients with higher SET gene expression had a higher level of white blood cell (WBC ≥ 100 × 10⁹/L) count than of lower SET gene expression ones (31.0% vs 11.4%, P=0.005). In the 136 patients who received treatment after diagnosis, higher SET gene expression group had lower complete remission rate (50.0%) than of lower expression cohort (73.5%) after two cycles of chemotherapy (P=0.005). Survival analysis showed that patients with higher SET gene expression had significantly shorter overall survival(OS) (10 months vs 22 months, P=0.001) and event-free survival (EFS) (2 months vs 14 months, P=0.005) than of lower SET gene expression ones. Multivariate COX regression analysis showed SET overexpression was an independent prognostic factor for OS. In the patients with the normal karyotype, higher SET expression group also had significantly shorter OS (12 months vs 35 months, P=0.010) and EFS (4 months vs 14 months, P=0.026) than of lower SET expression ones., Conclusion: High expression of SET gene was associated with poor prognosis and might be a prognostic molecular marker of AML.

Objective: To explore the HIRA gene sequences of 3'UTR region and elucidate the role of 3'UTR region of HIRA gene in the pathogenesis of tetralogy of Fallot (TOF)., Methods: Patients of TOF were confirmed by cardiac catheterization or surgery between April 2007 and December 2012 at our hospital. Mutations and single nucleotide polymorphisms (SNPs) were screened in 278 unrelated probands with isolated TOF and 515 controls. Target Scan was used to predict micro RNAs with possible combinations with 3'UTR region of HIRA gene. Dual-luciferase assay and real-time PCR were performed to detect the inhibition activity of micro RNAs on target genes. And χ(2) and t tests were used to analyze the results., Results: Statistically significant change occurred in the alleleic frequencies of existing SNPs (rs:117447448) between TOF patients and control group (11.5% (32/278) vs 4.9% (25/515), P = 0.001) . The combining site of miR328 was predicted to be 10 bp upstream of SNP site. MiR328 was expressed in heart and it was related with myocardial infarction and atrial fibrillation. Dual-luciferase assay showed a decreased level of luciferase after co-transfection with miR328 (0.012 5 ± 0.000 6 vs 0.019 6 ± 0.003 8, P = 0.034). So was the expression of HIRA (1.039 6 ± 0.077 2 vs 1.608 7 ± 0.274 9, P = 0.037). However, the luciferase level was not affected by SNP (rs:117447448) (P = 0.380)., Conclusions: The SNP (rs:117447448) of 3'UTR region of HIRA gene is related with TOF. HIRA is the target gene of miR328. Although SNP (rs:117447448) is not a major site of target gene HIRA for micro RNA328, it provides an important clue to in-depth studies of 3'UTR region of HIRA gene in the pathogenesis of TOF.

This study was aimed to investigate the occurrence and clinical significance of the SET-NUP214 fusion gene in patients with T-cell acute lymphoblastic leukemia (T-ALL), analyse clinical and biological characteristics in this disease. RT-PCR was used to detect the expression of SET-NUP214 fusion gene in 58 T-ALL cases. Interphase FISH and Array-CGH were used to detect the deletion of 9q34. Direct sequencing was applied to detect mutations of PHF6 and NOTCH1. The results showed that 6 out of 58 T-ALL cases (10.3%) were detected to have the SET-NUP214 fusion gene by RT-PCR. Besides T-lineage antigens, expression of CD13 and(or) CD33 were detected in all the 6 cases. Deletions of 9q34 were detected in 4 out of the 6 patients by FISH. Array-CGH results of 3 SET-NUP214 positive T-ALL patients confirmed that this fusion gene was resulted from a cryptic deletion of 9q34.11q34.13. PHF6 and NOTCH1 gene mutations were found in 4 and 5 out of 6 SET-NUP214 positive T-ALL patients, respectively. It is concluded that SET-NUP214 fusion gene is often resulted from del(9)(q34). PHF6 and NOTCH1 mutations may be potential leukemogenic event in SET-NUP214 fusion gene.

The purpose of this study was to analyze the gene rearrangement pattern of immunoglobulin and T-cell receptor (Ig/TR) and its clinical characteristics in three children with SET-NUP214 fusion gene positive leukemia/lymphoma. The transcript of SET-NUP214 fusion gene was detected by RT-nested PCR. The pattern of Ig/TR gene rearrangement was analyzed by using the BIOMED-2 multiplex PCR assays. Allelic-specific primers were designed for further monitoring the minimal residual disease (MRD). The results indicated that the fusion site located between exon 7 of SET and exon 18 of NUP214 at mRNA level in the three patients. The diagnoses were made as the mixed phenotype of acute leukemia (MPAL) for patients 1, acute T-lymphoblastic leukemia (T-ALL) for patients 2, and stage IV T-lymphoblastic lymphoma (T-LBL) for patients 3, respectively. Patient 1 responded to chemotherapy very poorly and relapsed at month 6 after hematopoietic stem cell transplantation. Patient 2 had high MRD (> 10(-2)) at the end of inducing remission therapy (day 33) which implied poor outcome, and died of toxic epidermal necrolysis and sequent serious infection. Patient 3 achieved hematological complete remission (CR) and MRD negative at day 15 and day 33 respectively. The duration of CR lasted for 30 months. Clonal TR gene rearrangements were detected in all the three patients. The rearrangements of TRD, TRG and TRB were found in patient 1 and 3. The rearrangements of TRD, TRB, IgH and IgK Kde were detected in patient 2. All the 6 TRB rearrangements detected were incomplete rearrangements, whereas 85.7% and 14.3% of the TRD, and TRG rearrangements were complete and incomplete, respectively. It is concluded that the transformation of SET-NUP214(+) leukemia/lymphoma cells may occur after the rearrangements of TRD and TRG and shortly after TRB rearrangement. The leukemia/lymphoma cells of patient 1 and 2 are more immature which may be related with poor outcome or response to chemotherapy.

Histone chaperones may participate the decondensation and assembly of chromatins, thus regulate gene expression. They play important roles in almost all developmental processes, such as gametogenesis, fertilization, embryogenesis, growth and senescence. In this review, we used well studied examples to illustrate various functions of histone chaperones during developmental processes. Focus is given to nucleoplasmin, CAF-1, HIRA, ASF1/CIA, and NAP1.