[Clinical features and prognosis of malignancy-associated hemophagocytic lymphohistiocytosis in children: a clinical analysis of 24 cases].

OBJECTIVE: To investigate the clinical features and prognosis of malignancy-associated hemophagocytic lymphohistiocytosis (MAHS) in children. METHODS: A retrospective analysis was performed for the primary diseases, clinical features, and prognosis of 24 children with MAHS. RESULTS: Among the 24 children, 11 (46%) had MAHS induced by tumor and 13 (54%) had chemotherapy-associated MAHS. As for primary diseases, 17 children had acute leukemia, 6 had lymphoma, and 1 had neuroblastoma. The most common clinical manifestations were pyrexia, respiratory symptoms, and hepatosplenomegaly. The most common laboratory abnormalities were hemocytopenia, elevated serum ferritin, and elevated lactate dehydrogenase. Of the 24 children, 22 were treated according to the HLH-2004 protocol and 2 gave up treatment; 18 children died, 1 was lost to follow-up, and 5 survived. The survival time ranged from 3 days to 2 years and 4 months (median 28 days). CONCLUSIONS: Children with MAHS have various clinical features and extremely poor treatment outcomes.

[Expression of CD146 in Adult and Children's Acute B Cell Lymphoblastic Leukemia and Its Significance].

OBJECTIVE: To explore the differences of CD146 expression in adult and children's acute B cell lymphoblastic leukemia(B-ALL), and its relation with clinical features, molecular biological and cytogenctic claracteristics. METHODS: The expression of CD146 in bone marrow samples from adult and children's B-ALL patients were detected by flow cytometry (FCM) and the relation of CD146 abnormal high expression with the patients' clinical features, molecular biological and cytogenetical characteristics, as well as other antigens were analyzed. RESULTS: The abnormal high expression rates of CD146 in adult and children's B-ALL patients were 29.17% and 9.09% respectively, showing that the expression rate of CD146 in adult patients was higher than that in children's patients(P<0.05). In adult B-ALL, CD146 was positively related with CD64 and CD117, while in children's B-ALL CD146 was positively related with CD71 and CD58 (P<0.05). After 1 course of standardized chemotherapy, the complete remission rates in adult and children's B-ALL patients with abnormal high expression of CD146 both were low as compared with adult and children's B-ALL without abnormal high expression of CD146 (P<0.05). CONCLUSION: The expression rate of CD146 in adult B-ALL is higher than that in children's B-ALL. The CD146 positively relates with poor prognostic antigens, the CD146 may be one poor prognosis marker.

Screening of human chromosome 21 genes in the dorsolateral prefrontal cortex of individuals with Down syndrome.

The aim of the current study was to identify the genes on human chromosome 21 (HC21) that may serve important functions in the pathogenesis of Down syndrome (DS). The microarray data GSE5390 were obtained from the Gene Expression Omnibus database, which contained 7 DS and 8 healthy normal samples. The data were then normalized and the differentially expressed genes (DEGs) were identified using the LIMMA package and Bonferroni correction. Furthermore, the DEGs underwent clustering and gene ontology analysis. Additionally, the locations of the DEGs on HC21 were confirmed using human genome 19 in the University of California, Santa Cruz Interaction Browser. A total of 25 upregulated and 275 downregulated genes were screened between DS and healthy samples with a false discovery rate of <0.05 and |logFC|>1. The expression levels of these genes in the two samples were different. In addition, the up­ and downregulated genes were markedly enriched in organic substance biological processes (P=4.48x10­10) and cell­cell signaling (P=0.000227). Furthermore, 17 overexpressed genes were identified on the 21q21­22 area, including COL6A2, TTC3 and ABCG1. Together, these observations suggest that 17 upregulated genes on HC21 may be involved in the development of DS and provide the basis for understanding this disability.

[Hydroa vacciniforme-like lymphoma: two cases report and literatures review].

OBJECTIVE: Two children with hydroa vacciniforme-like lymphoma (HVLL) were reported for a better understanding of this disease. METHODS: The clinical manifestation, pathological characteristics, therapeutic outcomes of two children with HVLL were analyzed and presented by compared with what described in literatures. RESULTS: Two children were girls, who treated firstly in the hospital in May 2012, July 2012 and their duration were 1 years, more than 10 years respectively. Their clinical manifestations were both limbs and craniofacial polymorphous rashes. Pathological findings revealed that the dermis and subcutaneous tissue were profiled by atypical lymphocytic infiltration. Immunohistochemistry showed that the infiltration of cells from T/NK cell, and Epstein-Barr virus encoded small RNA (EBER)(+). Case 1 was treated with chemotherapy, but her condition continued to deteriorate. Case 2 just received symptomatic treatment, her skin lesions gradually reduced and rash disappeared completely 2 months later. CONCLUSION: HVLL is found with special clinical manifestation, its diagnosis mainly depend on skin biopsy and immunohistochemistry, there is no specific treatment method now, and its prognosis still needs further research.

[Effects of FMS-like tyrosine kinase 3 targeted RNA interference on proliferation and apoptosis of acute monocytic leukemia cell line THP-1].

OBJECTIVE: FMS-like tyrosine kinase 3 (FLT3) is a receptor tyrosine kinase that is constitutively activated in (70-90)% pediatric patients with acute myeloid leukemia (AML) and appears to confer an adverse prognosis. Although several FLT3-selective small molecule inhibitors and antibodies were developed with varied degrees of success, to address the specificity and resistance, new approaches for specifically targeted FLT3 are needed and RNA interference is a promising choice. The aim of the present study was to investigate the efficacy of suppression of FLT3 induced by small hairpin interfering RNA (shRNA) on myeloproliferation and apoptosis in an acute monocytic leukemia (AMOL) cell line THP-1. METHODS: FLT3-targeted small hairpin interfering RNA (FLT3-shRNA) was designed and synthesized by transcription system in vitro was transfected into THP-1 cells. Firstly FLT3 mRNA level was detected by semi-quantitative RT-PCR and FLT3 protein level was detected by flow cytometry (FCM) to verify the efficacy on FLT3-shRNA interference at 48 h after transfection. Cell growth viability was measured at 24 h, 48 h and 72 h after treatment with CCK-8. The distribution of cell cycle was assayed by FCM, and apoptosis was analyzed by DNA Ladder and Annexin V-FITC Staining at 48 h. RESULTS: FLT3 targeted shRNAs was synthesized successfully and the concentration of 15 nmol/L for 48 h could obtain desirable downregulation of FLT3 expression, the inhibitory percentages of FLT3 mRNA and protein were (72.95 +/- 2.07)% and (65.39 +/- 5.57)%, respectively. The suppression of FLT3 induced by FLT3-shRNA resulted in marked inhibition of cell growth and the inhibitory percentages were (36.66 +/- 3.67)% at 48 h, (35.56 +/- 0.73)% at 72 h. FLT3-shRNA induced the inhibition of cell cycle from G(0)/G(1) phase to S phase, the percentage of sub-G(0)/G(1) phase (65.71 +/- 4.47)% was higher than those in the PBS-control group (52.23 +/- 2.98)%, NC-shRNA control group (51.81 +/- 1.44)%, P < 0.01; the percentage of S phase (25.11 +/- 2.70)% was lower than those in the PBS-control group (34.41 +/- 4.07)% and NC-shRNA control group (32.50 +/- 1.46)%, P < 0.05. Furthermore treatment with FLT3-shRNA for 48 h resulted in clear apoptosis ladder, the percentage of early apoptosis detected by Annexin V-FITC was (18.59 +/- 2.07)% which was significantly higher than that in the PBS-control group (4.00 +/- 0.50)% and the NC-shRNA control group (6.06 +/- 0.70)%, P < 0.001. CONCLUSION: The suppression of FLT3 induced by the shRNA can effectively inhibit cell proliferation, and apoptosis induction on THP-1 cells, which indicates that this approach may bear the therapeutic potential on childhood AMOL.

[In vitro transcription synthesis and effects of FLT3 targeted short hairpin RNA].

FMS-like tyrosine kinase 3 (FLT3) is a receptor of tyrosine kinase that is constitutively activated in most of acute myeloid leukemia patients and seems to give an adverse prognosis. In order to explore the silencing effect of FLT3 targeted short hairpin RNA (FLT3-shRNA) on acute leukaemia cell line THP-1, three FLT3-shRNAs (shRNA1, shRNA2, shRNA3) were designed and synthesized by transcription system in vitro and then transfected into THP-1 cells. FLT3 mRNA was analyzed by semi-quantitative RT-PCR, FLT3 protein was detected by Flow cytometry and immunofluorescence. The results indicated that FLT3 expression was downregulated by shRNA1 and shRNA3, and shRNA1 showed stronger inhibitory effect. At 48 hours following transfection, the inhibitory rate of 25 nmol/L shRNA1 was 72.95 +/- 2.07%, lasting 72 hours. The 5 nmol/L and more concentration of FLT3 shRNA1 could downregulate FLT3 mRNA level, which displayed a quantity-effect relation; the inhibitory rate of 15 nmol/L shRNA1 was 67.53 +/- 0.66%. FLT3 protein was located on THP-1 cell membrance, its expression was downregulated obviously by shRNA1, at 72 hours following transfection the inhibitory rate of shRNA1 was 79.67 +/- 0.66%. shRNA1 showed the best inhibitory effect on FLT3 protein, the optimal time of which was 72 hours with an inhibitory rate of 79.67%. It is concluded that FLT3-shRNA1 shows a desireable FLT3-targeted inhibitory effect, which can be used for further investigation of FLT3 mechanism or FLT3 targeting treatment.