CCAAT/enhancer-binding protein alpha (CEBPA) gene haploinsufficiency does not alter hematopoiesis or induce leukemia in Lck-CALM/AF10 transgenic mice

Although rare, CALM/AF10 is a chromosomal rearrangement found in immature T-cell acute lymphoblastic leukemia (T-ALL), acute myeloid leukemia, and mixed phenotype acute leukemia of T/myeloid lineages with poor prognosis. Moreover, this translocation is detected in 50% of T-ALL patients with gamma/delta T cell receptor rearrangement, frequently associated with low expression of transcription factor CCAAT/enhancer-binding protein alpha (CEBPA). However, the relevance of CEBPA low expression for CALM/AF10 leukemogenesis has not yet been evaluated. We generated double mutant mice, which express the Lck-CALM/AF10 fusion gene and are haploinsufficient for the Cebpa gene. To characterize the hematopoiesis, we quantified hematopoietic stem cells, myeloid progenitor cells, megakaryocyte-erythrocyte progenitor cells, common myeloid progenitor cells, and granulocyte-macrophage progenitor cells. No significant difference was detected in any of the progenitor subsets. Finally, we tested if Cebpa haploinsufficiency would lead to the expansion of Mac-1+/B220+/c-Kit+ cells proposed as the CALM/AF10 leukemic progenitor. Less than 1% of bone marrow cells expressed Mac-1, B220, and c-Kit with no significant difference between groups. Our results showed that the reduction of Cebpa gene expression in Lck-CALM/AF10 mice did not affect their hematopoiesis or induce leukemia. Our data corroborated previous studies suggesting that the CALM/AF10 leukemia-initiating cells are early progenitors with lymphoid/myeloid differentiating potential.

Expression and Clinical Significance of C/EBPα Gene in Elderly Multiple Myeloma / 中国实验血液学杂志

OBJECTIVE@#To investigate the expression of C/EBPα gene in elderly patients with multiple myeloma （MM） and its prognostic significance.@*METHODS@#Sixty-nine olderly patients with multiple myeloma (MM) treated in our hospital from February 2015 to October 2017 were selected and enrolled in the MM group, 38 healthy persons received physical examination were selected and enrolled in the control group. The bone marrow of 2 groups was collected and the mononuclear cells were isolated.The mRNA expression level of C/EBPα gene in mononuclear cells was determined by RT-PCR, the Western blot was used to detect the protin expression level of PBMNC C/EBPα, and the protein level of C/EBPα in bone marrow was detected by immunohistochemistry. The correlations of C/EBPα gene expression with the clinical characteristics and survival time in MM patients were analyzed.@*RESULTS@#The expression level of mRNA and protein of C/EBPα in MM patients was significantly lower than that in the control group (P0.05).Immunohistochemical staining showed that the bone marrow samples of the control group were stained more deeply, and the staining intensity in bone marrow samples of MM patients with CR, PR and relapse was successively descended. The protein level of C/EBPα in CR patients with MM was significantly higher than that in PR and relapsed patients by Western blot (P<0.05). Kaplan-Meier survival analysis showed that OS and DFS in the patients with high expression of C/EBPα gene were higher than those in low expression group (P<0.05). Multivariate Cox regression analysis showed that CRP,ratio of myeloma cells and C/EBPα gene were independent factors affecting OS and PFS (P<0.05).@*CONCLUSION@#The expression level of C/EBPα gene in MM patients is low that may stimulate the genesis of MM, and the expression of C/EBPα gene closely relates with the development of MM disease.

Dynamic expression and role of SUMO-modified C/EBPα in preterm rats with bronchopulmonary dysplasisa induced by hyperoxia exposure / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the expression of SUMO-modified CCAAT enhancer binding protein α (C/EBPα) in preterm rat model of bronchopulmonary dysplasisa (BPD) induced by hyperoxia exposure and its role.</p><p><b>METHODS</b>Eighteen preterm rats were randomly divided into an air group and a hyperoxia group (n=9 each). The model of BPD was prepared in preterm rats exposed to hyperoxia. The rats from the two groups were sacrificed on postnatal days 4, 7 and 14 respectively (3 rats at each time) and lung tissues were harvested. Periodic acid-Schiff (PAS) staining was used to observe the differentiation of rat lung tissues. Ki67 expression was detected by immunohistochemistry. Western blot was used to measure the protein expression of small ubiquitin-related modifier-1(SUMO1) and C/EBPα. A co-immunoprecipitation assay was performed to measure the protein expression of SUMO-modified C/EBPα.</p><p><b>RESULTS</b>Compared with the air group, the hyperoxia group showed a decreased glycogen content in the lung tissue on postnatal day 4, and an increased content on postnatal days 7 and 14. Over the time of hyperoxia exposure, the hyperoxia group showed an increased expression of Ki67 in the lung tissue compared with the air group at all time points. Compared with the air group, the protein expression of C/EBPα increased on postnatal day 4 and decreased on postnatal days 7 and 14 in the hyperoxia group (P<0.05). The hyperoxia group had significantly upregulated expression of SUMO1 and SUMO-modified C/EBPα compared with the air group at all time points (P<0.05). In the hyperoxia group, the protein expression of SUMO-modified C/EBPα was positively correlated with the glycogen content (r=0.529, P<0.05) and the expression of Ki67 (r=0.671, P<0.05).</p><p><b>CONCLUSIONS</b>Hyperoxia may induce over-proliferation and differentiation disorders of alveolar epithelial cells in preterm rat model of BPD, possibly through an increased expression of SUMO-modified C/EBP&alpha.</p>

Roles of CCAAT enhancer binding protein α in acute myeloblastic leukemia / 浙江大学学报·医学版

The CCAAT enhancer binding protein α (C/EBP α:p42 and p30),which encoded by CCAAT enhancer binding protein α () gene,plays a pretty crucial role in the regulation of myeloid hematopoiesis.The disorder of CEBPA gene expression is an pivotal mechanism of acute myeloid leukemia (AML). The result of uncontrolled expression of C/EBP α gene is the over-expression of p30 and the incomplete loss of p42, both of which contribute to the occurrence of AML. Restoring the expression ratio of C/EBP α such as over-expression of p42 or blocking the carcinogenic pathway of p30 seems to be important for the treatment of AML caused by such causes. In order to better guide medical decision-making, this article reviews research progress on C/EBPα in the pathogenesis of AML.

Effect of H. pylori on the expression of CCAAT enhancer binding protein α and Cx43 and its role in gastric carcinogenesis / 中南大学学报(医学版)

OBJECTIVE@#To explore the effect of H. pylori on the expression of CCAAT enhancer binding protein α (C/EBPα) and connexin 43 (Cx43) in gastric carcinogenesis.
@*METHODS@#Different gastric mucosal epithelial cell lines (GES-1 cells, AGS cells and SGC-7901 cells) were cultured. A total of 6 cases of chronic non-atrophic gastritis tissues, 12 cases of gastric precancerous lesions tissues and 12 cases of gastric cancer tissues were collected under endoscopy. The expression of C/EBPα and Cx43 mRNA in the above-mentioned cells and tissues was detected by real-time PCR. The GES-1 cells and East Asian CagA+ H. pylori strains were co-cultured for 24 and 48 h as an experimental group, and those cell lines without H. pylori infection were cultured for 24 and 48 h as a control group. Real-time PCR and Western bolt were used to detect the expression of mRNA and proteins of C/EBPα and Cx43 in GES-1 cells, respectively.
@*RESULTS@#The expressions of C/EBPα and Cx43 mRNA in the AGS and SGC-7901 cells were lower than those in GES-1 cells (all P<0.05), and both of them decreased more profoundly in the SGC-7901 cells than those in the AGS cells (both P<0.05). The expressions of C/EBPα and Cx43 mRNA were lower in the gastric cancer tissues than those in the chronic non-atrophic gastritis tissues (both P<0.05) and gastric precancerous lesion tissues (both P<0.05). The C/EBPα expression was positively correlated with Cx43 expression (gastric precancerous lesion tissues: r=0.679, gastric cancer tissues: r=0.792; both P<0.05). Compared with the control group, the expressions of C/EBPα and Cx43 mRNA and protein in the experimental group were decreased at 24 and 48 h after culture (both P<0.05), which were lower at 48 h than those at 24 h (both P<0.05).
@*CONCLUSION@#H. pylori infection can down-regulate the expressions of C/EBPα and Cx43 on gastric epithelial cells, which may be associated with gastric carcinogenesis.

Epimedium koreanum Nakai and its main constituent icariin suppress lipid accumulation during adipocyte differentiation of 3T3-L1 preadipocytes / 中国天然药物

Obesity is associated with a number of metabolic abnormalities such as type 2 diabetes and has become a major health problem worldwide. In the present study, we investigated the effects of Epimedium koreanum Nakai (Herba Epimedii, HE) and its main constituent icariin on the adipocyte differentiation in 3T3-L1 preadipocytes. HE extract and icariin significantly reduced lipid accumulation and suppressed the expressions of PPARγ, C/EBPα, and SREBP-1c in 3T3-L1 adipocytes. They also inhibited fatty acid synthase (FAS), acyl-Co A synthase (ACS1), and perilipin. Moreover, HE extract and icariin markedly increased the phosphorylation of AMPK. These results indicated that HE extract and icariin can inhibit the adipocyte differentiation through downregulation of the adipogenic transcription factors, suggesting that HE containing icariin may be used as a potential therapeutic agent in the treatment and prevention of obesity.

Comparison of Adipogenesis and Adipocyte Functions of 3T3-L1 Cells and Human Bone Marrow Mesenchymal Stem Cells In Vitro / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To compare the adipogenesis and the adipocyte function between 3T3-L1 cells and human bone marrow mesenchymal stem cells (MSCs) in vitro.</p><p><b>METHODS</b>By density gradient centrifugation and adherent culture, the MSCs were isolated from human bone marrow and purified. The cell morphology was observed under an inverted microscope. After the induction of adipogenic differentiation, the differentiation level was detected by oil red O staining and OD values. The expression of PPARγ, FABP4 and C/EBPα mRNA was detected by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). Adipocytes and THP-1 cells were co-cultured by adding 1 µg/ml cytarabine. The ability of chemotherapy resistance was measured after 48 h.</p><p><b>RESULTS</b>The Oil Red O staining and measuring the absorbance showed that the lipid content in 3T3-L1 cells group was more than that in MSCs group, and the OD value was higher than that in MSCs group (P < 0.05). The results of qRT-PCR showed that the relative expression of PPARγ, FABP4 and C/EBPα mRNA of 3T3-L1-derived adipocytes was higher than that of human bone marrow MSCs-derived adipocytes (P < 0.05). Coculture experiments showed that the number of viable THP-1 cells in the group containing adipocytes was more than that in the control group (P < 0.05). The difference between 3T3-L1 cell group and MSC group was statistically significant (P < 0.05).</p><p><b>CONCLUSION</b>The ability of adipogenesis of 3T3-L1 cells is higher than that of human bone marrow MSCs in vitro. Adipocytes can protect THP-1 cell line against cytarabine, and the effect of adipocytes from 3T3-L1 cell group is greater than that from the human bone marrow MSC group.</p>

Metformin Influences the Effect of Adipocytes on Leukemia Cell Chemoresistance through Regulation of Adipogenesis / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the effect of metformin on 3T3-L1 preadipocyte's differentiation and consequently observe the anti-proliferative effects of metformin-treated adipocytes on leukemia cells.</p><p><b>METHODS</b>Different concentrations of metformin were added in 3T3-L1 preadipocytes to induce maturation, the matured adipocytes were detected by oil red O staining and quantified by absorbance value (OD). Real-time PCR was used to detect the mRNA expression level of the key adipogenic genes PPARγ, C/EBPα and FABP4(ap2). The adipocytes were co-cultured with GFP+-THP-1 cells, 1 µg/ml of cytarabine(Ara-C) was added and incubated for 48 hours, the flow cytometry was used to detect the apoptosis rate of GFP+-THP-1 cells. Adipocyte supernatant was collected and mixed with equal volume of tumor lysat medium (RPMI 1640) at 1:1 to culture tumor cells. The leukemia cell proliferation activity was detected by CCK-8; after 48 hours of adding 1 µg/ml Ara-C, the protective effect on chemotherapy was assayed by using cytometer.</p><p><b>RESULTS</b>The metformin lowered the OD value, and the expression levels of both adipogenic genes C/EBPα and FABP4 were lower than those of controls, while the expression level of PPARγ mRNA was not significantly changed, the apoptosis rate of leukemia cells co-caltured with metformin-treated adipocytes was higher than that of co-cultured cells without metformin treatment. The adipocytes promoted the leukimia cell proliferation and protected leukemia cells from chemotherapy, which could be abrogated by metformin.</p><p><b>CONCLUSION</b>The metformin can inhibit the differentiation of 3T3-L1 preadipocytes into adipocytes, and can regulate the protective effect of adipocytes on the apoptosis, proliferation and chemotherapy of leukemia cells.</p>

miR-328 Inhibits K562 Cell Proliferation by Up-regulation of C/EBPα Expression / 中国实验血液学杂志

<p><b>OBJECTIVE</b>Our research was aim to investigate the effect of microRNA-328 (miR-328) on proliferation of chronic myeloid leukemia(CML) cell K562 and the mediated effect of C/EBPα.</p><p><b>METHODS</b>The eukaryotic expression vectors of miR-328 targeting gene and suppressor gene (hsa-miR-328 and hsa-miR-328-inhibitor) were constructed, and transfected into K562 cells respectively. The mRNA expression levels of miR-328 and C/EBP α were detected by real-time fluorescence quantitative RT-PCR; C/EBP α protein expression was detected by Western blot; CCK-8 was used to estimate the cell viability.</p><p><b>RESULTS</b>The recombinant genes of hsa-miR-328 and hsa-miR-328-inhibitor were successfully constructed and transfected into K562 cells. Fluorescent cells were observed after 24 h, and the visible fluorescence cells were gradually increased after 48 h or 72 h, the miR-328 showed no effect on the mRNA expression of C/EBPα detected by RT-PCR. Meanwhile, miR-328 showed recovering effect on C/EBPα translation and inhibition of K562 cells proliferation.</p><p><b>CONCLUSION</b>miR-328 has been successfully constructed and transfected into K562 cells, miR-328 inhibits the proliferation of K562 cells by up-regulation of C/EBPα.</p>

The expression and role of the transcription factor C/EBPα in chronic myeloid leukemia / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the expression and the possible mechanism of the transcription factor C/EBPα in chronic myeloid leukemia（CML).</p><p><b>METHODS</b>Bone marrow samples from 50 CML patients（including 33 patients in chronic phase, 7 in accelerated phase and 10 in blast crisis）and peripheral blood specimens of 20 healthy donors were collected. The expression of C/EBPα gene and the effect of Imatinib on its expression was detected by RT- PCR. C/EBPα gene was inserted into lentivirus expression vector pLVX- EGFP- 3FLAG- Puro by recombinant DNA technology to construct C/EBPα stable expression in K562 cells. Cell proliferation was assayed by CCK-8. The expressions of Foxo3a and Bim genes were detected by RT-PCR.</p><p><b>RESULTS</b>The level of C/EBPα expression was significantly declined in CML patients compared with that of normal control group（P<0.01）and had negative correlation with bcr- abl expression（Spearman r=－ 0.505, P<0.01). The stable K562- C/EBPα cell line was successfully established and confirmed by RT-PCR and Western blot. Cell proliferation ability was lower in the K562- C/EBPα group than that in the non- transfection and mock-vehicle groups. The expressions of Foxo3a and Bim genes were 1.06 ± 0.06 and 0.53 ± 0.07, respectively, which was higher than that of nontransfection and mock-vehicle groups（P<0.01, P<0.05).</p><p><b>CONCLUSION</b>C/EBPα expression was decreased in CML patients, overexpression of C/EBPα could inhibit K562 cell growth.</p>

Effect of Vascular Cell Adhesion Molecule -1 Overexpression on Adipogenic Differentiation of Murine Mesenchymal Stem Cells and Its Mechanism / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the effect of vascular cell adhesion molecule-1 (VCAM-1) gene overexpression on adipogenic differentiation of mouse mesenchymal stem cells(MSC) and explore its molecular mechanism.</p><p><b>METHODS</b>VCAM-1 overexpression MSC (MIGR1-VCAM-1/MSC) and the empty plasmid transfection MSC (MIGR1/MSC) were induced to adipogenic differentiation, oil-red-O staining and real-time PCR were used to detect the adipogenic differentiation ability and the mRNA expression level of key transcription factors C/EBP α and PPAR γ. The activation of P38, ERK and JNK pathways were analyzed by Western blot. Furthermore, the specific chemical inhibitors of MAPK pathway (SB203580, PD98059 and JNK inhibitor II) were added to the induced culture system and the alteration of the MSC adipogenic differentiation ability were evaluated.</p><p><b>RESULTS</b>no matter in self or induced differentiation groups, the lipid droplets in MIGR1-VCAM-1/MSC became larger, the amount of adipocyte increased than that in MIGR1/MSC (P<0.01), the mRNA expression level of C/EBPα and PPARγ were upregulated, and JNK pathway were down-regulated while the P38 and ERK pathway were significantly up-regulated. The inhibition of JNK pathway of MIGR1-VCAM-1/MSC could lead to increased mRNA expression level of C/EBP α and PPAR γ, the amount of adipocytes increased (P<0.01), however, the inhibition of the P38 and ERK pathway of MIGR1-VCAM-1/MSC could lead to decreased mRNA expression level of C/EBP α and PPAR γ, and the lipid droplets and the number of adipocytes became smaller and less.</p><p><b>CONCLUSION</b>The overexpression of VCAM-1 may promote MSC to differentiate into adipocytes through inhibiting JNK signaling pathway, activating P38 and ERK pathways.</p>

C/EBPα in multiple myeloma patients may lead to increased hepcidin / 中国实验血液学杂志

This study was aimed to explore the possible mechanisms of hepcidin increase in multiple myeloma patients. The clinical information and peripheral venous blood of eligible patients with previously untreated multiple myeloma were collected. Serum concentration of IL-6 was detected by ELISA. Peripheral blood monocytes were isolated by CD14⁺ magnetic beads. The expression of hepcidin, IL-6 and C/EBPα mRNA of monocytes were detected by real time quantitative PCR. The results indicated that the hemoglobin level was reduced in 17 multiple myeloma patients enrolled in study (97.8 ± 27.5 g/L), showing the characteristics of anemia of chronic disease. The hepcidin and C/EBPα expression of peripheral blood monocytes significantly increased (P < 0.01), serum IL-6 was also higher than that in normal controls (P < 0.01). Serum IL-6 positively correlated with monocyte hepcidin and C/EBPα expression (P < 0.05); monocyte C/EBPα expression positively correlated with monocyte hepcidin expression (P < 0.05). It is concluded that the elevated IL-6 may induce hepcidin expression through up-regulating C/EBPα in untreated myeloma patients.

Novel Mutations in CEBPA in Korean Patients with Acute Myeloid Leukemia with a Normal Karyotype

Mutations in the transcription factor CCAAT/enhancer binding protein alpha gene (CEBPA) are found in 5-14% of the patients with AML and have been associated with a favorable clinical outcome. In this study, we aimed to assess the frequencies and characteristics of mutations in CEBPA. Between 2006 and 2009, CEBPA mutations were assessed using archival DNA samples obtained from 30 consecutive adult patients diagnosed with AML with a normal karyotype at our institution. CEBPA mutations were detected using direct sequencing analyses. These mutations were detected and described with reference to GenBank Accession No. NM_004364.3. In our series, CEBPA mutations were detected in 4 patients (13.3%). These mutations occurred as double mutations in all 4 patients. Among the 8 mutant alleles, 5 were novel (c.179_180dupCG, c.50_53delGCCA, c.178_182delACGTinsTTT, c.243_244insGTCG, and c.923_924insCTC). The frequency of occurrence of CEBPA mutations in Korean patients with AML is comparable to that in previous reports. Long-term follow-up data from a larger series of patients with comprehensive molecular profiling are needed to delineate the prognostic implications.

Expression of c/ebpα gene in MDS and its clinical significance / 中国实验血液学杂志

This study was aimed to investigate the expression of CCAAT/enhancer binding protein alpha gene (c/ebpα) in patients with myelodysplastic syndromes (MDS) and to explore the significance of c/ebpα in pathogenesis and progression of MDS. Real time quantitative reverse transcriptase polymerase chain reaction (RQ-PCR) method was used to detect the expression level of c/ebpα mRNA in bone marrow mononuclear cells (BMMNC) of 33 patients with MDS and 14 normal controls. The results showed that the expression level of c/ebpα mRNA in low-risk and high-risk MDS was significantly lower than that of normal controls (p < 0.01, p < 0.001, respectively), moreover, high-risk MDS showed lower c/ebpα mRNA expression compared with low-risk MDS (p < 0.05). c/ebpα mRNA expression level in MDS was not correlated with sex, age and peripheral blood cell amount, while the ratio of blast cells in bone marrow was in the c/ebpα mRNA low expression group significantly higher than that in the high expression group (p < 0.01). It is concluded that down-regulation of c/ebpα mRNA expression level has closely associated with the pathogenesis of MDS, the c/ebpα may be an important molecular biological marker of MDS; the degree of down-regulated c/ebpα has closely related to the progression of MDS.

Effects of PI3K inhibitor LY294002 on the differentiation of mouse preadipocytes and the expression of C/EBPα and PPARγ / 中国当代儿科杂志

<p><b>OBJECTIVE</b>This study examined the effects of PI3K inhibitor LY294002 on the differentiation of mouse preadipocytes and the expression of CCAAT enhancer binding protein α (C/EBPα) and peroxisome proliferation activated receptor γ (PPARγ), in order to study the possible roles of insulin receptor substrate (IRSs)/PI3K signal pathway in the differentiation of preadipocytes.</p><p><b>METHODS</b>The mouse 3T3-L1 cells were cultured normally and divided into experimental and control groups. 3T3-L1 cells in the experimental group were treated with PI3K inhibitor LY294002 (25 μmol/L) and those in the control group were treated with DMSO culture medium. 3-isobutyl-1-methylxanthine (IBMX) (0.5 mmol/L), dexamethasone (10-6 mol/L) and insulin (5 μg/mL) were used to induce the differentiation of 3T3-L1 preadipocytes in both groups. Before culture, and 2, 4 and 8 days after culture, the cells were collected to detect the expression of C/EBPα and PPARγ by real-time PCR and Western blot assays. The lipid droplets of 3T3-L1 preadipocytes were observed by oil-red O staining.</p><p><b>RESULTS</b>PI3K inhibitor LY294002 did not affect the expression of C/EBPα and PPARγ in un-induced 3T3-L1 preadipocytes (P>0.05), but decreased the expression of C/EBPα and PPARγ during the in vitro induced differentiation of 3T3-L1 preadipocytes compared with the control group (P<0.05 or 0.01). The lipid droplets count was greatly reduced by LY294002.</p><p><b>CONCLUSIONS</b>PI3K inhibitor LY294002 can inhibit the differentiation of mouse 3T3-LI preadipocytes and the expression of C/EBPα and PPARγ in the differentiation of 3T3-LI preadipoeytes, suggesting that IRSs/PI3K signal pathway may play an important role in the differentiation of 3T3-L1 preadipocytes by regulating the expression of C/EBPα and PPARγ.</p>

Effects of huanglian jiedu decoction and its disassembled recipes containing serums on the proliferation and differentiation of preadipocytes / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To study the effects and mechanisms of Huanglian Jiedu Decoction (HJD) and its disassembled recipes containing serums on the proliferation and differentiation of preadipocytes.</p><p><b>METHODS</b>HJD and its disassembled recipes containing serums were prepared. The 3T3-L1 preadipocytes were cultured. The proliferation of 3T3-L1 preadipocytes was detected by methyl thiazolyl tetrazolium (MTT) method. The accumulation of lipid droplets in the cytoplasm of differentiated preadipocytes was observed by oil red O staining and quantitatively analyzed by colorimetry. The mRNA expressions of peroxisome proliferation activated receptor y (PPAR gamma) and CAAT/enhancer binding protein (C/EBP alpha) were detected by reverse transcription polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>Intervention with serum containing HJD, Phellodendron amurense Rupr plus Gardenia jasminoides Ellis, or Gardenia jasminoides Ellis showed significantly stimulative effects on the proliferation of preadipocytes, as compared with that in the blank control group (P<0.05, P<0.01). The preadipocytes treated with serum containing HJD, Phellodendron amurense Rupr plus Gardenia jasminoides Ellis, Coptis chinensis Franch or Gardenia jasminoides Ellis showed that the lipid droplets in the cytoplasm were significantly lessened, so did the mRNA expressions of PPAR gamma and C/EBP alpha when compared with the blank control group (P<0.05, P<0.01).</p><p><b>CONCLUSIONS</b>HJD promoted the proliferation of preadipocytes, decreased the accumulation of lipid droplets during the differentiation of adipocytes, and inhibited the differentiation of adipocytes, which might be associated with its effects on decreasing the mRNA expressions of PPAR gamma and C/EBP alpha. Phellodendron amurense Rupr and Gardenia jasminoides Ellis were the main components of HJD playing these roles.</p>

Anti-obesity effects of Lysimachia foenum-graecum characterized by decreased adipogenesis and regulated lipid metabolism

Lysimachia foenum-graecum has been used as an oriental medicine with anti-inflammatory effect. The anti-obesity effect of L. foenum-graecum extract (LFE) was first discovered in our screening of natural product extract library against adipogenesis. To characterize its anti-obesity effects and to evaluate its potential as an anti-obesity drug, we performed various obesity-related experiments in vitro and in vivo. In adipogenesis assay, LFE blocked the differentiation of 3T3-L1 preadipocyte in a dose-dependent manner with an IC50 of 2.5 microg/ml. In addition, LFE suppressed the expression of lipogenic genes, while increasing the expression of lipolytic genes in vitro at 10 microg/ml and in vivo at 100 mg/kg/day. The anti-adipogenic and anti-lipogenic effect of LFE seems to be mediated by the inhibition of PPARgamma and C/EBPalpha expression as shown in in vitro and in vivo, and the suppression of PPARgamma activity in vitro. Moreover, LFE stimulated fatty acid oxidation in an AMPK-dependent manner. In high-fat diet (HFD)-induced obese mice (n = 8/group), oral administration of LFE at 30, 100, and 300 mg/kg/day decreased total body weight gain significantly in all doses tested. No difference in food intake was observed between vehicle- and LFE-treated HFD mice. The weight of white adipose tissues including abdominal subcutaneous, epididymal, and perirenal adipose tissue was reduced markedly in LFE-treated HFD mice in a dose-dependent manner. Treatment of LFE also greatly improved serum levels of obesity-related biomarkers such as glucose, triglycerides, and adipocytokines leptin, adiponectin, and resistin. All together, these results showed anti-obesity effects of LFE on adipogenesis and lipid metabolism in vitro and in vivo and raised a possibility of developing LFE as anti-obesity therapeutics.

Effect of C/EBPalpha on the monocytic differentiation of HL60 cells induced by NSC67657 / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To figure out the function of C/EBPalpha in the monocytic differentiation of HL60 cells induced by a new steroidal drug NSC67657.</p><p><b>METHODS</b>The differentiation of HL60 cells was induced by NSC67657, and the cell surface antigen CD14 expression was detected by flow cytometry. The gene and protein expressions of CCAAT enhancer binding protein alpha (C/EBPalpha) before and after the induction of cell differentiation were determined by RT-PCR and Western blot. Eukaryotic expressing vector pDsRed-ICAT was constructed and transfected into HL60 cells, and its expression was verified. The effect of C/EBPalpha overexpression in HL60 cells was assessed by MTT assay, Wright's staining and flow cytometry before and after NSC67657 transfection.</p><p><b>RESULTS</b>HL60 cells could be induced into monocytes by 10 micromol/L ATRA within 5 days, and the coverage of CD14 positive cells reached 93.9% after 5 days of drug treatment. The eukaryotic expressing vector was successfully constructed, and over 90% positive clones were obtained after screening by G418 and electrotransfection. The results of proliferative analysis, chemical staining, ultrastructural observation, and CD11b detection confirmed that HL60 cells could be induced into granulocytic differentiation by overexpression of C/EBPalpha protein. Moreover, in the drug treatment group, transfected cells could not be induced into monocytic differentiation, and their granulocytic differentiation was also inhibited.</p><p><b>CONCLUSION</b>The monocytic differentiation of HL60 cells induced by NSC67657 may not be via the regulation by C/EBPalpha protein-mediated signal transduction. However, the overexpression of CEBPalpha may inhibit the process of NSC67657-induced monocytic differentiation in HL60 cells.</p>

Analysis of CEBPA mutation in acute myeloid leukemia / 中国实验血液学杂志

In order to evaluate the incidence of CCAAT/enhancer binding protein alpha (cebpa) gene mutation in patients with acute myeloid leukemia (AML), 22 AML patients with normal karyotype (NK-AML) were enrolled in this study, including de novo AML and relapsed AML. The cebpa gene was amplified by 2 stages using genomic DNA as template, the cebpa gene mutation amplified product was detected by direct sequencing or clone sequencing. The results showed that the cebpa mutations including deletion and insertion were found in 4 out of 22 AML patients (18.2%) and all of these 4 patients were M(2). Two patients had N-terminal nonsense mutation and the other two had C-terminal in-frame mutation. It is concluded that PCR combined with direct sequencing and clone sequencing can be used to detect cebpa mutations. cebpa mutations are mainly identified in M(2) subtype of NK-AML patients, its significance for prognosis needs to further investigate.

Regulation mechanism for rig-g gene expression induced by all-trans retinoic acid / 中国实验血液学杂志

To investigate the molecular mechanisms of all-trans retinoic acid (ATRA)-induced rig-g gene expression and to better understand the signal transduction of ATRA during acute promyelocytic leukemia (APL) cell differentiation, the luciferase reporter assay, co-immunoprecipitation and chromatin immunoprecipitation were used to clarify the basic transcriptional factors, which directly initiated the expression of rig-g gene. The results showed that the expression of STAT2, IRF-9 and IRF-1 could be upregulated by ATRA with different kinetics in NB4 cells. IRF-9 was able to interact with STAT2 to form a complex, which could bind the rig-g gene promoter and trigger the rig-g expression. IRF-1 alone could also activate the reporter gene containing rig-g gene promoter, but C/EBPalpha could strongly inhibit this transcription activity of IRF-1. It is concluded that during ATRA-induced APL cell differentiation, IRF-1 is first upregulated by ATRA, and then IRF-1 increases the protein levels of IRF-9 and STAT2 with the downregulation of C/EBPalpha. The complex of IRF-9 and STAT2 is the primary transcriptional factor for rig-g gene induction. This study will be helpful for better understanding the signal transduction networks of ATRA during the course of APL cell differentiation.