Ginsenoside Rd Induces Differentiation of Myeloid Leukemia Cells via Regulating ERK/GSK-3ß Signaling Pathway.

OBJECTIVE: To investigate the role of ginsenoside Rd (GRd) in acute myeloid leukemia (AML) cell differentiation. METHODS: AML cells were treated with GRd (25, 50, 100 and 200 µg/mL), retinoic acid (RA, 0.1g/L) and PD98059 (20 mg/mL) for 72 h, cell survival was detected by methylthiazolyldiphenyl-tetrazolium bromide and colony formation assays, and cell cycle was detected by flow cytometry. Cell morphology and differentiation were observed by Wright-Giemsa staining, peroxidase chemical staining and cellular immunochemistry assay, respectively. The protein expression levels of GATA binding protein 1 (GATA-1), purine rich Box-1 (PU.1), phosphorylated-extracellular signal-related kinase (p-ERK), ERK, phosphorylated-glycogen synthase kinase-3ß (p-GSK3ß), GSK3ß and signal transducer and activator of transcription 1 (STAT1) were detected by Western blot. Thirty-six mice were randomly divided into 3 groups using a random number table: model control group (non-treated), GRd group [treated with 200 mg/(kg·d) GRd] and homoharringtonine (HTT) group [treated with 1 mg/(kg·d) HTT]. A tumor-bearing nude mouse model was established, and tumor weight and volume were recorded. Changes of subcutaneous tumor tissue were observed after hematoxylin and eosin staining. WT1 and GATA-1 expressions were detected by immunohistochemical staining. RESULTS: The cell survival was inhibited by GRd in a dose-dependent manner and GRd caused G0/G1 cell arrest (p<0.05). GRd treatment induced leukemia cell differentiation, showing increased expressions of peroxidase and specific proteins concerning erythrogenic or granulocytic differentiation (p<0.05). GRd treatment elicited upregulation of p-ERK, p-GSK-3ß and STAT1 expressions in cells, and reversed the effects of PD98059 on inhibiting the expressions of peroxidase, GATA-1 and PU.1 (P<0.05). After GRd treatment, tumor weight and volume of mice were decreased, and tumor cells underwent massive apoptosis and necrosis (P<0.05). WT1 level was decreased, and GATA-1 level was significantly increased in subcutaneous tumor tissues (P<0.05 or P<0.01). CONCLUSION: GRd might induce the differentiation of AML cells via regulating the ERK/GSK-3ß signaling pathway.

Chinese Medicine Regulates DNA Methylation to Treat Haematological Malignancies: A New Paradigm of "State-Target Medicine".

Aberrant regulation of DNA methylation plays a crucial causative role in haematological malignancies (HMs). Targeted therapy, aiming for DNA methylation, is an effective mainstay of modern medicine; however, many issues remain to be addressed. The progress of epigenetic studies and the proposed theory of "state-target medicine" have provided conditions to form a new treatment paradigm that combines the "body state adjustment" of CM with targeted therapy. We discussed the correlation between Chinese medicine (CM) syndromes/states and DNA methylation in this paper. Additionally, the latest research findings on the intervention and regulation of DNA methylation in HMs, including the core targets, therapy status, CM compounds and active components of the Chinese materia medica were concisely summarized to establish a theoretical foundation of "state-target synchronous conditioning" pattern of integrative medicine for HMs, simultaneously leading a new perspective in clinical diagnosis and therapy.

[Effect of Petroleum Ether Extract of Rhizoma Amorphophalli on Biological Characteristics of K562 Cells and Its Mechanism].

OBJECTIVE: To investigate the role of petroleum ether extract of Rhizoma Amorphophalli (SLG) in inhibiting proliferation and promoting apoptosis and differentiation of leukemia K562 cells. METHODS: K562 cells were processed by SLG and PD98059 which was the ERK signaling pathway blocker. Then cell vitality was tested by MTT. Cell apoptosis rate and positive percentage of antigen expression related with differentiation were detected by flow cytometry. The protein expression levels of ERK1/2 and pERK1/2 were detected by Western blot. RESULTS: The proliferation activity of K562 was reduced by 50, 100, 200 mg/L SLG in a concentration dependent manner (r=0.9997). The apoptosis rate and positive expression rate of CD11b, CD14 and CD42b which were related with differentiation were raised by SLG, as well as the expression of pERK1/2, while PD98059 could reverse the promoting effect of SLG on apoptosis and differentiation partially. CONCLUSION: SLG can inhibit the proliferation and promote apoptosis and differentiation of K562 cells through ERK signaling pathway.

Chinese Medicine Treatment on Graft-Versus-Host Disease after Allogeneic Hematopoietic Stem Cell Transplantation.

Graft-versus-host disease (GVHD) is the most common complication after allogeneic hematopoietic stem cell transplantation, and also an important factor affecting the survival and quality of life in patients after transplantation. Currently, immunosuppressive therapy is commonly used for GVHD, but the curative effect is not ideal. How to effectively prevent and treat GVHD is one of the difficulties to be solved urgently in the field of transplantation. In this paper, we summarize the latest progress in pathogenesis, prevention and treatment of GVHD with Chinese medicine (CM). We hope it will provide ideas and methods for exploring the mechanism and establishing a new comprehensive therapy for GVHD with CM.

Panaxdiol Saponins Component Promotes Hematopoiesis and Modulates T Lymphocyte Dysregulation in Aplastic Anemia Model Mice.

OBJECTIVE: To investigate the potential efficacy of panaxadiol saponins component (PDS-C) in the treatment of aplastic anemia (AA) model mice. METHODS: Totally 70 mice were divided into 7 groups as follows: normal, model, low-, medium-, high-dose PDS-C (20, 40, 80 mg/kg, namely L-, M-, H-PDS-C), cyclosporine (40 mg/kg), and andriol (25 mg/kg) groups, respectively. An immune-mediated AA mouse model was established in BALB/c mice by exposing to 5.0 Gy total body irradiation at 1.0 Gy/min, and injecting with lymphocytes from DBA mice. On day 4 after establishment of AA model, all drugs were intragastrically administered daily for 15 days, respectively, while the mice in the normal and model groups were administered with saline solution. After treatment, the peripheral blood counts, bone marrow pathological examination, colony forming assay of bone marrow culture, T lymphocyte subpopulation analysis, as well as T-bet, GATA-3 and FoxP3 proteins were detected by flow cytometry and Western blot. RESULTS: The peripheral blood of white blood cell (WBC), platelet, neutrophil counts and hemoglobin (Hb) concentration were significantly decreased in the model group compared with the normal group (all P<0.01). In response to 3 dose PDS-C treatment, the WBC, platelet, neutrophil counts were significantly increased at a dose-dependent manner compared with the model group (all P<0.01). The myelosuppression status of AA was significantly reduced in M-, H-PDS-C groups, and hematopoietic cell quantity of bone marrow was more abundant than the model group. The colony numbers of myeloid, erythroid and megakaryocytic progenitor cells in the model group were less than those of the normal mice in bone marrow culture, while, PDS-C therapy enhanced proliferation of hematopoietic progenitor cells by significantly increasing colony numbers (all P<0.01). Furthermore, PDS-C therapy increased peripheral blood CD3+ and CD3+CD4+ cells and reduced CD3+CD8+ cells (P<0.05 or P<0.01). Meanwhile, PDS-C treatment at medium- and high doses groups also increased CD4+CD25+FoxP3+ cells, downregulated T-bet protein expression, and upregulated GATA-3 and FoxP3 protein expressions in spleen cells (P<0.05). CONCLUSION: PDS-C possesses dual activities, promoting proliferation hematopoietic progenitor cells and modulating T lymphocyte immune functions in the treatment of AA model mice.

Auxin production in diploid microsporocytes is necessary and sufficient for early stages of pollen development.

Gametophytic development in Arabidopsis depends on nutrients and cell wall materials from sporophytic cells. However, it is not clear whether hormones and signaling molecules from sporophytic tissues are also required for gametophytic development. Herein, we show that auxin produced by the flavin monooxygenases YUC2 and YUC6 in the sporophytic microsporocytes is essential for early stages of pollen development. The first asymmetric mitotic division (PMI) of haploid microspores is the earliest event in male gametophyte development. Microspore development in yuc2yuc6 double mutants arrests before PMI and consequently yuc2yuc6 fail to produce viable pollens. Our genetic analyses reveal that YUC2 and YUC6 act as sporophytic genes for pollen formation. We further show that ectopic production of auxin in tapetum, which provides nutrients for pollen development, fails to rescue the sterile phenotypes of yuc2yuc6. In contrast, production of auxin in either microsporocytes or microspores rescued the defects of pollen development in yuc2yuc6 double mutants. Our results demonstrate that local auxin biosynthesis in sporophytic microsporocytic cells and microspore controls male gametophyte development during the generation transition from sporophyte to male gametophyte.

Ginseng-Derived Panaxadiol Saponins Promote Hematopoiesis Recovery in Cyclophosphamide-Induced Myelosuppressive Mice: Potential Novel Treatment of Chemotherapy-Induced Cytopenias.

OBJECTIVE: To investigate the potential efficacy of panaxadiol saponins component (PDS-C), a biologically active fraction isolated from total ginsenosides, to reverse chemotherapy-induced myelosuppression and pancytopenia caused by cyclophamide (CTX). METHODS: Mice with myelosuppression induced by CTX were treated with PDS-C at a low- (20 mg/kg), moderate- (40 mg/kg), or high-dose (80 mg/kg) for 7 consecutive days. The level of peripheral white blood cell (WBC), neutrophil (NEU) and platelet (PLT) were measured, the histopathology and colony formation were observed, the protein kinase and transcription factors in hematopoietic cells were determined by immunohistochemical staining and Western blot. RESULTS: In response to PDS-C therapy, the peripheral WBC, NEU and PLT counts of CTX-induced myelosuppressed mice were significantly increased in a dose-dependent manner. Similarly, bone marrow histopathology examination showed reversal of CTX-induced myelosuppression with increase in overall bone marrow cellularity and the number of hematopoietic cells (P<0.01). PDS-C also promoted proliferation of granulocytic and megakaryocyte progenitor cells in CTX-treated mice, as evidenced by significantly increase in colony formation units-granulocytes/monocytes and -megakaryocytes (P<0.01). The enhancement of hematopoiesis by PDS-C appears to be mediated by an intracellular signaling pathway, this was evidenced by the up-regulation of phosphorylated mitogen-activated protein kinase (p-MEK) and extracellular signal-regulated kinases (p-ERK), and receptor tyrosine kinase (C-kit) and globin transcription factor 1 (GATA-1) in hematopoietic cells of CTX-treated mice (P<0.05). CONCLUSIONS: PDS-C possesses hematopoietic growth factor-like activities that promote proliferation and also possibly differentiation of hematopoietic progenitor cells in myelosuppressed mice, probably mediated by a mechanism involving MEK and ERK protein kinases, and C-kit and GATA-1 transcription factors. PDS-C may potentially be a novel treatment of myelosuppression and pancytopenia caused by chemotherapy.

Effects of bufalin on up-regulating methylation of Wilm's tumor 1 gene in human erythroid leukemic cells.

OBJECTIVE: To explore the effects of bufalin on inhibiting proliferation, up-regulating methylation of Wilm' tumor 1 gene (WT1) as well as its possible mechanisms in human erythroid leukemic (HEL) cells. METHODS: The HEL cells were treated with bufalin at various concentrations to observe cellular morphology, proliferation assay and cell cycle. The mRNA and protein expression levels of WT1 were detected by reverse transcription polymerase chain reaction (RT-PCR), Western blot and immunocytochemistry, DNA methylation of WT1 and protein expression levels of DNA methyltransferase 3a (DNMT3a) and DNMT3b were analyzed by methylation-specific PCR, and Western blot respectively. RESULTS: The bufalin was effective to inhibit proliferation of HEL cells in a dose-dependent manner, their suppression rates were from 23.4%±2.1% to 87.2%±5.4% with an half maximal inhibit concentration (IC50) of 0.046 µmol/L. Typical apoptosis morphology was observed in bufalin-treated HEL cells. The proliferation index of cell cycle decreased from 76.4%±1.9% to 49.7%±1.3%. The expression levels of WT1 mRNA and its protein reduced gradually with increasing doses of bufalin, meanwhile, the methylation status of WT1 gene changed from unmethylated into partially or totally methylated. While, the expression levels of DNMT3a and DNMT3b protein gradually increased by bufalin treatment in a dose-dependent manner. CONCLUSIONS: Bufalin can not only significantly inhibit the proliferation of HEL cells and arrest cell cycle at G0/G1 phase, but also induce cellular apoptosis and down-regulate the expression level of WT1. Our results provide the evidence of bufalin for anti-leukemia, its mechanism may involve in increasing WT1 methylation status which is related to the up-regulation of DNMT3a and DNMT3b proteins in erythroid leukemic HEL cells.