Notch1 signaling inhibits growth of EC109 esophageal carcinoma cells through downmodulation of HPV18 E6/E7 gene expression.

AIM: To investigate the role of the Notch1 signaling pathway in growth arrest of an esophageal carcinoma cell line (EC109) in vitro and the mechanism involved. METHODS: An intracellular domain of Notch1 (ICN) was transfected into cultured EC109 cells by lipofectamine transfection. Subsequently, the proliferation of the transfected cells was measured by an MTT assay. Cell cycle distribution was analyzed by flow cytometry. Human papillomavirus type 18 (HPV18) E6/E7 mRNA expression was detected by RT-PCR, and p53 protein expression was detected by Western blot. RESULTS: Activation of Notch1 signaling resulted in inhibition of EC109 cell proliferation with the induction of G(2)/M arrest, downmodulation of HPV18 E6/E7 gene expression, and upregulation of p53 expression. CONCLUSION: Repression of HPV18 E6/E7 expression by Notch1 signaling results in the activation of p53-mediated pathways with concomitant growth suppression of HPV18-positive EC109 cells.

[Treatment of stage IV neuroblastoma with allogeneic hematopoietic stem cell transplantation in children].

OBJECTIVE: At present there is no effective therapeutic approach for stage IV neuroblastoma. We report our experience with allogenic hematopoietic stem cell transplantation as a means of treating this disorder in one child. METHODS: A 7-year-old boy with stage IV neuroblastoma received allogenetic hematopoietic stem cell transplantation. The donor was his mother who was haploid HLA-matched to the patient. Conditioning regimen consisted of fludarabin and melphalan. Stem cells were collected from peripheral blood and bone marrow of the donor. RESULTS: The patient achieved hematopoietic reconstruction and was converted to full donor chimerism according to short tandem repeat sequence-polymerase chain reaction detection. The patient's neutrophil count recovered to more than 0.5 x 10(9)/L 10 days after transplantation. The patient's platelet count recovered to more than 20 x 10(9)/L 11 days after transplantation. Acute graft versus host disease occurred 8 days after transplantation and was improved after treatment. The patient survived in a 210-day-follow-up. CONCLUSIONS: Haploid HLA-matched allogeneic hematopoietic stem cell transplantation from parent donor was an alternative, safe and effective treatment for children with stage IV neuroblastoma.

[Expression of FoxO3a in patients with acute myeloid leukemia and its clinical significance].

This study was aimed to investigate the expression and clinical significance of forkhead box protein O3a (FoxO3a) in the patients with acute myeloid leukemia (AML). Western blot was used to detect the FoxO3a protein expression in bone marrow samples from 44 newly diagnosed AML patients and 5 healthy donors. Additionally, 14 patients' samples were reevaluated when they got complete remission (CR). The results showed that FoxO3a expression (FoxO3a/ß-actin 0.43 ± 0.19) in newly diagnosed AML patients was much higher than that in healthy donors (FoxO3a/ß-actin 0.19 ± 0.06) (P < 0.001). The FoxO3a level was down-regulated when CR was got and there was not significant difference between patients in CR and healthy donors (P > 0.10). The correlation analysis showed that the level of FoxO3a expression positively correlated with the white blood cell count of AML patients at the time of diagnosis. Although FoxO3a expression did not positively correlate with the CR rate, the higher FoxO3a expression in AML patients showed a shorter remission duration. It is concluded that FoxO3a may be a oncoprotein in AML, and the high FoxO3a expression is associated with poor prognosis.

[Inhibitory effect of phenylhexyl isothiocyanate on notch signaling of multiple myeloma cells in vitro].

In order to investigate the mechanisms of phenylhexyl isothiocyanate (PHI) inhibiting the proliferation of multiple myeloma cell RPMI8226 in vitro, the RPMI8226 cells were co-cultured with PHI of various concentrations. The inhibition of proliferation was measured by MTT test and the cell apoptosis was assayed by DAPI staining. The changes of Notch1, Jagged2, BCL-2 and p-Akt proteins in the PHI-treated cells were detected by Western blot. The results showed that PHI inhibited RPMI8226 cell proliferation in certain concentration range and induced their apoptosis. The inhibiting effect caused by PHI showed a concentration-and time-dependent manner. The PHI decreased expressions of Notch1 and Jagged2 proteins in a concentration-and time-dependent manners, the levels of BCL-2 and p-Akt declined at the same time. It is concluded that PHI can inhibit proliferation of RPMI8226 cells, and induce their apoptosis. The cell apoptosis is associated with the inhibition of Notch signaling and downstream targets BCL-2 and p-Akt proteins of RPMI8226 cells, PHI may be a new Notch signaling inhibitor and a promising therapeutic drug for multiple myeloma.

[Simultaneous detection of FLT3-ITD and NPM1 gene mutations in acute myeloid leukemia by double PCR].

Objective of this study was to establish a method for simultaneous detection of FLT3/ITD and NPM1 gene mutations in AML. A double PCR was firstly designed and optimized to amplify both exon 12 of NPM1 and exon 14-intron 14-exon 15 of FLT3, with the aim of detecting almost all reported mutations. After optimization, a touchdown PCR was chosen for the multiplex PCR procedure, with the primer concentrations of NPM1 and FLT3-ITD being 200 nmol/L and 152 nmol/L respectively. The PCR amplicons were separated by capillary electrophoresis and the presence of mutants was recognized by the size difference between the mutants and wild-type products. The areas of mutant peak and wild-type peak were used to calculate the mutant/wild-type ratio. All the positive mutated samples were confirmed by sequencing. The results showed that 17 patients with NPM1 mutation, 15 patients with FLT3-ITD mutation, 6 patients with both NPM1 and FLT3-ITD mutations were found among 93 patents. 7 patients with M2, 4 patients with M4, 5 patients with M5 and 1 patients with M6 were found out of 17 patients with NPM1 mutation, in which 10 patients were male and 7 patients were female, 15 patients were with type A, 1 patients was with type B and 1 patients was with type Nm, strikingly 1 CML patient in blast crisis was found to carry a type A mutation. Among 15 patients with FLT3-ITD mutation 1 patient with M1, 8 patients with M2, 2 patients with M2, 2 patients with M3, 1 patient with M4, 3 patients with M5 were found, in which 5 patients were male and 10 patients were female. Sequencing results further confirmed the accuracy and reliability of this method. It is concluded that a novel method with the ability to detect both FLT3-ITD and NPM1 mutations has been developed when genomic DNA was templated. This method is fast, easy, accurate and capable to calculate the mutant/wild-type ratio.

[Expression of pituitary tumor transforming gene in patients with AML].

The aim of study was to explore the expression of pituitary tumor-transforming gene (pttg) in acute myeloid leukemia (AML) and its relationship with the pathogenesis of AML, simultaneously to investigate the difference of the pttg expression among AML different subtypes. The expressions of pttg mRNA were quantitatively detected by real-time fluorescence quantitative polymerase chain reaction (real-time PCR) in bone marrow from 47 patients with AML and 28 normal controls. The results indicated that the expression of pttg mRNA was significantly higher in AML patients [(1.1323 ± 1.3934) × 10(5)] than that in normal controls [(4.5766 ± 1.1817) × 10(3)] (p < 0.05). The expression of pttg mRNA was higher in M(3) patients than that in other AML subtypes, such as M(1), M(2), M(4), M(5). It is concluded that the overexpression of pttg may be related to the pathogenesis and progression of AML, in which the overexpression of pttg may be more intimately related to the pathogenesis and progression of M(3). This study provides a new idea to research the pathogenesis and targeted gene therapy of AML.

[Expression of FLT3 internal tandem duplication in pediatric patients with acute myeloid leukemia and its correlation with multidrug resistance].

This study was aimed to investigate the expression of FLT3 internal tandem duplication (FLT3-ITD) in pediatric patients with acute myeloid leukemia (AML) and to analyse the clinical features of patients with mutations and the relation of FLT3-ITD with multidrug resistance gene 1 (mdr1). RT-PCR was used to determine the expressions of FIT3-ITD and mdr1 gene in bone marrow samples from 81 new diagnosed pediatric patients with AML, the cytogenetics and immunophenotypes of bone marrow cells were routinely examined. The results indicated that the FLT3-ITDs were detected in 8 out of 81 pediatric patients (9.88%) and all mutations detected were hybrid, while less frequently this mutation was detected in adult patients. Although they were irrelevant with sex and immunophenotypes, the mutations seemed predominant in older pediatric patients. The leukocyte counts and bone marrow blast cell counts in pediatric patients with FLT3-ITD at diagnosis were higher than those in pediatric patients without FLT3-ITD (p = 0.001 and p = 0.041 respectively), but the normal chromosomes were found in most pediatric patients with FLT-ITD. The patients with FLT3-ITD had lower induction remission rate (only 25%), but the patients without FLT3-ITD had higher remission rate (76.1%). According results detected by RT-PCR, the mdr1 gene was found in 27 pediatric patients, but only 3 out of 8 pediatric patients with FLT3-ITD were detected to express both FLT3-ITD and mdr1, which suggests unrelation between FLT3-ITD occurrence and mdr1 expression. It is concluded that the FLT3-ITD is frequent mutation in pediatric patients with AML, the prognosis is worse and the induction remission rate is lower in these patients, but the FLT3-ITD not relates with the mdr1, which suggests that the common MDR modulators may be un effective for therapy of the patients with FLT3-ITD.