Objective To investigate the mechanism of matrine in inhibition of proliferation the proliferation of human chronic myeloid leukemia (CML) K562 cells via MEK-ERK signaling pathway. Methods Western blot was used to detect the expression of MEK1, ERK1/2, Shc and SHP2 (the signal effect molecules of MEK-ERK pathway) in K562 cells. The transcription and translation of bcr-abl and target protein (bcl-xL, Cyclin D1, c-myc and p27) were detected by RT-PCR and Western blot. Results Matrine was able to significantly inhibit the phosphorylation of MEK1, ERK1/2, Shc and SHP2 in K562 cells and suppress the protein and mRNA expression of bcr-abl. Moreover, the expressions of bcl-xL, Cyclin D1 and c-myc were down-regulated significantly, while the expression level of p27 (a negative regulator of cell cycle progression) was increased markedly after matrine treatment. Conclusions Suppression of the growth of human CML K562 cells is related to the inhibition of bcr-abl-mediated MEK-ERK pathway activity. The down-regulation of phosphorylated proteins or protein kinases activity in signaling pathways might be an important molecular mechanism in control the activity of MEK-ERK pathway.

OBJECTIVETo correlate the clinical features of patients with acute myeloid leukemia (AML) with mutations of FLT3-ITD, NPM1, CEBPA, c-KIT, DNMT3A and ND4 genes as well as chromosomal aberrations.

METHODSSomatic mutations of aforementioned genes in 412 newly diagnosed AML patients were detected with PCR and direct sequencing. All patients were also subjected to R-banding chromosomal analysis. The results were correlated with the clinical features and prognosis of the patients.

RESULTSThe mutation rates of FLT3-ITD, NPM1, CEBPA, c-KIT, DNMT3A and ND4 were 9.0% (26/289), 19.1% (50/262), 18.9% (34/180), 3.4% (7/208), 6.6% (9/137) and 6.9% (4/58), respectively. Patients with poor prognosis based on genetic mutations had lower blood platelet count than those with intermediate and good prognosis (P=0.001 and P=0.001, respectively). None of the three groups attained median overall survival (OS) (P> 0.05). The complete remission (CR) was similar among the three groups (P> 0.05). For patients with different prognosis based on cytogenetic findings, white blood cell count in those with intermediate prognosis was higher than those with good and poor prognosis (P< 0.001 and P=0.004, respectively), while the blood platelet count of the intermediate group was higher than that of the group with good prognosis (P=0.018). No significant difference was found among the three groups in terms of hemoglobin level (P> 0.05). The group with poor prognosis has attained shorter OS compared with those with good and intermediate prognosis (P< 0.001 and P=0.003, respectively). However, the CR rate of the group with good prognosis was higher than that of the intermediate group (P=0.001). For the group with intermediate prognosis, presence of genetic mutations did not correlate with the clinic characteristics such as white blood cell count, blood platelet count, hemoglobin level, OS and CR rate (P> 0.05 for all comparisons).

CONCLUSIONGenetic mutations combined with cytogenetic analysis can facilitate the prognosis and personalized treatment for patients with AML.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Child ; Child, Preschool ; Female ; Humans ; Infant ; Leukemia, Myeloid, Acute ; genetics ; mortality ; Male ; Middle Aged ; Mutation ; Prognosis ; Young Adult

In the earliest days,the idea that surviving a single infection often resulted in lifelong immunity to the infecting pathogen was recorded and then led to the discovery of vaccination.We have now confirmed that such protection is primarily based on the generation of immunological memory in antibody response.With the wide implementation of more and more vaccines around the world,it is well documented that different vaccines have different potential regarding to the duration of antibody response.In clinical observations,live-attenuated vaccines often elicit long-term immunity but are also accompanied with risks in safety that are hard to avoid.In order to develop novel vaccines with both excellent potential in eliciting antibody memory and low safety risk,it is critical to further investigate the mechanism of antibody memory in the perspective of immunology.Antibody memory is mediated by certain long-lived B cells:long-lived plasma cell can secret antibody to maintain serum antibody titer while memory B cell contributes to the rapid immune response during the secondary encounter of pathogens.Cellular and molecular processes that drive the production of long-lived plasma cells and memory B cells are subjects of intensive research and have important implications for global health.Several factors in the vaccine would indeed affect and regulate these processes,including the antigen valency,vaccine kinetics and the signal integration of both antigen and danger molecules.Many studies have focused on strategies to manipulate these factors to improve or develop new vaccines.Here,we will summarize our current knowledge on how the component in vaccines will affect their potential in generating and sustaining antibody memory,and also point out the challenges we face in the route of developing a"perfect"vaccine.

OBJECTIVETo probe matrine acting on natural killer cell (NK) activating receptor NKG2D ligands expression in CML cell line K562 and its underlying molecular mechanism.

METHODSThe expression of NKG2D ligands (major histocompatibility complex class I chain-related molecule A or B (MICA/B), UL16-binding proteins (ULBP) 1, 2, and 3 on K562 cells were analyzed before and after treated with matrine by FCM. The cytotoxic sensitivity of K562 to NK cell was detected by FCM after CFSE staining at different effect-to-target (E/T) cell ratios. The expression of signal transduction and transcriptional activator 3 (STAT3) protein as well as phosphorylated STAT3 (p-STAT3) were detected by western blot.

RESULTSAfter treatment with matrine, ULBP1 and ULBP2 expression, especially ULBP2 on K562 cells significantly increased, with mean fluorescence intensity (MFI) increasing to 615 and 1614 by 220 and 615 in the untreated cells, respectively. There was no significant change for MICA or ULBP3 expression. Matrine enhanced the susceptibility of K562 cells to NK-mediated cell lysis. At the ratio of E/T with 5:1, the proportion of the killed K562 cells increased to 32.8%, 38.1% and 40.5%, respectively (after 0.2, 0.5 and 0.8 mg/ml matrine treatment) by 29.2% in the untreated cells. The phosphorylated STAT3 protein, but not STAT3 protein, was significantly inhibited by matrine treatment in K562 cells.

CONCLUSIONMatrine induced the expression of NKG2D ligands in K562cells and enhanced the cytotoxicity of NK cells against K562, which was closely related to the inhibition of STAT3 activity in K562 cell.

Alkaloids ; pharmacology ; GPI-Linked Proteins ; immunology ; Humans ; Intercellular Signaling Peptides and Proteins ; immunology ; K562 Cells ; Quinolizines ; pharmacology ; Signal Transduction ; Up-Regulation ; drug effects

OBJECTIVETo investigate the molecular mechanism of the growth inhibitory effect of matrine on K562 cells in JAK/STAT3 mediated signal pathway.

METHODSWestern blot analyses were performed to investigate the differential expression of JAK2, STAT3, phosphor-STAT3 (Tyr705 & Ser727) and phosphor-JAK2 proteins after matrine treatment in K562 cells with or without human recombinant interleukin 6 (IL-6) pretreatment. The expression of STAT3 response gene products such as Bcl-xL, Cyclin D1 and c-Myc, were investigated by Western blot and quantitative real time RT-PCR (qRT-PCR). Expression of IL-6, a potent upstream activating factor of JAK/STAT3 pathway, was analyzed by both real time qRT-PCR and ELISA.

RESUTLSWestern blot revealed that matrine treatment resulted in a strong down-regulation of phosphor-STAT3 both in Tyr705 and Ser727 sites or phosphor-JAK2 proteins expression without significant effects on the total STAT3 and JAK2 proteins. The expression of phosphor-Tyr705 STAT3 and phosphor-Ser727 STAT3 was decreased to 0.370 ± 0.172 in K562 cells treated with 0.5 mg/ml matrine for 48 h, respectively, from 0.690 ± 0.119 and 1.150 ± 0.263 in control cells, accompanied with a dramatical down-regulation of phosphor-JAK2 from 0.670 ± 0.137 to 0.049 ± 0.057 (P<0.05). In addition, it was found that the expression of Bcl-xL, Cyclin D1, c-Myc was decreased both at the transcription and protein level in K562 cells after matrine treatment. Matrine treatment resulted in a significant decrease in the expression level of IL-6 in K562 cells from (35.1 ± 1.93) to (10.74 ± 1.83) and (8.66 ± 1.24) pg/ml at the dose of 0.5 and 0.8 mg/ml, respectively (p<0.05). Matrine treatment could diminish the up-regulation of STAT3, JAK2, phosphor-STAT3 and phosphor-JAK2 protein following pretreatment with IL-6 in K562 cells.

CONCLUSIONMatrine exerts its anti-leukemia effect by interfering with the JAK2/STAT3 signaling pathway. The inhibition of IL-6 expression may play a pivotal role in the disruption of JAK/STAT pathway by matrine.

Alkaloids ; Down-Regulation ; Humans ; Interleukin-6 ; Janus Kinase 2 ; K562 Cells ; Quinolizines ; STAT3 Transcription Factor ; Signal Transduction ; Up-Regulation

Amyloid beta (Aβ) plaques are one of the hallmarks of Alzheimer's disease (AD). However, currently available anti-amyloid therapies fail to show effectiveness in the treatment of AD in humans. It has been found that there are different types of Aβ plaque (diffuse and focal types) in the postmortem human brain. In this study, we aimed to investigate the correlations among different types of Aβ plaque and AD-related neuropathological and cognitive changes based on a postmortem human brain bank in China. The results indicated that focal plaques, but not diffuse plaques, significantly increased with age in the human hippocampus. We also found that the number of focal plaques was positively correlated with the severity of AD-related neuropathological changes (measured by the "ABC" scoring system) and cognitive decline (measured by the Everyday Cognitive Insider Questionnaire). Furthermore, most of the focal plaques were co-localized with neuritic plaques (identified by Bielschowsky silver staining) and accompanied by microglial and other inflammatory cells. Our findings suggest the potential of using focal-type but not general Aβ plaques as biomarkers for the neuropathological evaluation of AD.
Alzheimer Disease/pathology* ; Amyloid beta-Peptides/metabolism* ; Amyloid beta-Protein Precursor ; Brain/pathology* ; Cognitive Dysfunction/pathology* ; Hippocampus/metabolism* ; Humans ; Neuroinflammatory Diseases ; Plaque, Amyloid/pathology*