Analysis of Correlation of WAS Gene Mutations with Clinical Phenotype / 中国实验血液学杂志

OBJECTIVE@#To investigate the gene mutation of patients with WAS gene defect and its correlation with clinical manifestations.@*METHODS@#Thirty-one patients consulted in Children's Hospital of Soochow University from January 2013 to February 2018 were enrolled in this study. The hot pot mutations of WAS gene in 31 patients were detected and related clinical phenotypes were analyzed retrospectively.@*RESULTS@#All patients were male. The median onset age was 1 month (range, 0-83 months). Nine mutants were reported as novel mutations among 25 mutants detected in 31 patients, including c.1234_1235dupCC, c.1093-1097delG, c.28-30dupC, c.436G>T, c.273 + 10_273 + 11dupCC, c.995_996insG, c.1010T>A, c.332_333delCC and c.683C>T mutations. There were 25 cases of classic WAS which mutations included missense mutation, deletion mutation, insertion mutation, splicing mutation and nonsense mutation, 2 cases of X-linked thrombocytopenia (XLT) were induced by missense mutation, 1 case of intermittent X-linked thrombocytopenia (IXLT) was induced by splicing mutation, 2 cases of X-linked pancytopenia were induced by missense mutation. Intravenous immunoglobulin (IVIG) and glucocorticoid therapy in IXLT patient was effective, and remission could be sustained, platelets could be increased in the short-term in treated XLT patients, but only a small part of classic WAS patients(8.0%) showed transient response to it, the IVIG and glucocorticoid therapy did not improve the status of platelet in XLP patients. Immune laboratory examination showed that CD3 was decreased in 60.0% patients, CD19 was decreased in 12.0% patients, and CD56CD16 in 4 patients was decreased, accounting for 16.0%. Out of 24 patients, 22 patients were alive after treated with hematopoietic stem cell transplantation (HSCT), 4 patients who were not given HSCT died of brain bleeding and severe infection, 1 patient diagnosed as IXLT got remission and survived.@*CONCLUSION@#WAS gene defect is an important basis for the diagnosis of WAS and related diseases. IVIG plus glucocorticoid therapy is less effective for fewer patients, the HSCT is an effective treatment for WAS.

Mechanism of Paris Forrestii (Takht.) H. Li-Suppressing the Proliferation of Acute Myeloid Leukemia Cell Lines / 中国实验血液学杂志

OBJECTIVE@#To investigate the mechanism of Paris forrestii (Takht.) H. Li (PCT3)-suppressing the proliferation of HL-60, K562, KG-1 and HT-93 cells.@*METHODS@#cute myeloid leukemia cell lines such as HL-60, K562, KG-1 and HT-93 were treated with Paris forrestii (Takht.) H. Li (PCT3) for 24, 48, and 72 h, and MTT assay was employed to determine the cells proliferation. Meanwhile, the apoptosis of K562, HL-60, KG-1 and HT-93 cells were detected by flow cytometry after PCT3 (Control, 4 μg/ml, 8 μg/ml) treated for 24 h and the Western blot was performed to detect the expression of PARP,Caspase-3, MCL-1, BAX, BCL-2, P53, and P27. GAPDH was used as an internal loading control.@*RESULTS@#MTT assay showed that Paris forrestii (Takht.) H. Li (PCT3) significantly inhibited the proliferation of HL-60, K562, KG-1 and HT-93 cells in concentration and time-dependent manners. Compared with the control group, the leukemia cell viabilities were significantly suppressed (r =0.9436; r =0.8623; r =0.9922; r =0.8918). Paris forrestii (Takht.) H. Li (PCT3) induced apoptosis of leukemia cells in a concentration dependent manner, compared with the control group (P＜0.05 or P＜0.01). Western blot revealed that PARP, a major enzyme in DNA damage repair, and Caspase-3 another one of the major executive apoptotic enzymes were cleaved in cell lines examined, and this cleavage was concentration dependent. Anti-apoptotic proteins such as MCL-1 and BCL-2 were down regulated by Paris forrestii (Takht.) H. Li (PCT3), and Pro-apoptotic protein BAX was upregulated. And the protein of tumor suppressor gene P53 and its downstream signaling protein P27 increased.@*CONCLUSION@#Paris forrestii (Takht.) H. Li (PCT3) can inhibit the proliferation of leukemia cells by activating endogenous apoptosis pathway, and provide a potential new drug selection for clinical treatment of AML leukemia.

Saponins from Paris forrestii(Takht.)H.Li displays potent activity against acute myeloid leukemia by suppressing RNF6/AKT/mTOR signaling pathway / 中国药理学与毒理学杂志

Acute myeloid leukemia (AML) is a heterogeneous disease characterized by the accu-mulation of immature myeloid progenitor cells in the bone marrow,compromising of normal hematopoi-esis and ultimately resulting in bone marrow failure. Chemotherapy is the mainstay treatment for all AML patients,however,drug resistance and clinical relapse limits its efficacy.The 5-year survival rate of AML patients is only 26.6%.Survival rates are even lower among patients ages 65 to 74 years (5.3%)and 75 years or older(1.6%).Therefore,exploring novel therapeutic agents is urgent for improving the outcome of patients with AML. Saponins are amphipathic glycosides found in traditional Chinese medicines. In the present study, we isolated a panel of saponins from Paris forrestii (Takht.) H. Li, a unique plant found in Tibet and Yunnan provinces, China. By examining their activities in suppressing acute myeloid leukemia cell proliferation, total saponins from Paris forrestii (TSPf) displayed more potent activity than individual ones.TSPf induced more than 40% AML cell apoptosis within 24 h and decreased the viability of all leukemia cell lines. TSPf-induced apoptosis was confirmed by both Annexin V staining and caspase-3 activation.TSPf downregulated pro-survival proteins Mcl-1,Bcl-xL and Bcl-2,but upreg-ulated the expression of tumor suppressor proteins p53,p27,Bax and Beclin 1.The AKT/mTOR signaling pathway is frequently over activated in various AML cells,and TSPf was found to suppress the activa-tion of both AKT and mTOR,but had no effects on their total protein expression.This was further con-firmed by the inactivation of 4EBP-1 and p70S6K,two typical downstream signal molecules in the AKT/mTOR pathway. More specifically, TSPf-inactivated AKT/mTOR signaling was found to be associated with downregulated RNF6, a recently identified oncogene in AML. RNF6 activated AKT/mTOR, and consistently, knockdown of RNF6 led to inactivation of the AKT/mTOR pathway. Furthermore, TSPf suppressed the growth of AML xenografts in nude mice models. Oral administration of 100 mg·kg-1 body weight almost fully suppressed tumor growth within 14 d, without gross toxicity. This study thus demonstrated that TSPf displays potent anti-AML activity by suppressing the RNF6/AKT/mTOR pathway. Given its low toxicity,TSPf could be developed for the treatment of AML.