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.

Background: Co-infections of the porcine reproductive and respiratory syndrome virus (PRRSV) and the Haemophilus parasuis (HPS) are severe in Chinese pigs, but the immune response genes against co-infected with 2 pathogens in the lungs have not been reported. Objectives: To understand the effect of PRRSV and/or HPS infection on the genes expression associated with lung immune function. Methods: The expression of the immune-related genes was analyzed using RNA-sequencing and bioinformatics. Differentially expressed genes (DEGs) were detected and identified by quantitative real-time polymerase chain reaction (qRT-PCR), immunohistochemistry (IHC) and western blotting assays. Results: All experimental pigs showed clinical symptoms and lung lesions. RNA-seq analysis showed that 922 DEGs in co-challenged pigs were more than in the HPS group (709 DEGs) and the PRRSV group (676 DEGs). Eleven DEGs validated by qRT-PCR were consistent with the RNA sequencing results. Eleven common Kyoto Encyclopedia of Genes and Genomes pathways related to infection and immune were found in single-infected and co-challenged pigs, including autophagy, cytokine-cytokine receptor interaction, and antigen processing and presentation, involving different DEGs. A model of immune response to infection with PRRSV and HPS was predicted among the DEGs in the co-challenged pigs. Dual oxidase 1 (DUOX1) and interleukin-21 (IL21) were detected by IHC and western blot and showed significant differences between the co-challenged pigs and the controls. Conclusions These findings elucidated the transcriptome changes in the lungs after PRRSV and/or HPS infections, providing ideas for further study to inhibit ROS production and promote pulmonary fibrosis caused by co-challenging with PRRSV and HPS.

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

OBJECTIVETo investigate the relationship of the mutational status of the ND4 gene and the clinical features of acute myelogenous leukemia (AML) patients with ND4 mutations.

METHODSUsing PCR combined with directly sequencing, we identified somatic mutations of ND4 in 121 primary AML patients to couple with their clinical features.

RESULTSThere were 58 male patients and 63 female patients (median age 49 years, 10-86 years). Eight of 121 patients (6.6%) with de novo AML were found harboring missense mutation of ND4 gene, including 3 patients with A131V (3/8, 37.5%), 2 patients with A404T (2/8, 25%), 1 patient with F149L (1/8, 12.5%), 1 patient with G242D (1/8, 12.5%) and 1 patient with Y409H (1/8, 12.5%), respectively. Patients with ND4 mutations were associated with good karyotype (P=0.049), regardless of gender, age, white blood cell, hemoglobin, platelet, blast cells of bone marrow or immunophenotype (P>0.05). There were no statistical significance in mutations of FLT3-ITD, NPM1, CEBPA, c-KIT and DNMT3A between patients with ND4 mutation and wild-type (wt) ND4 (P>0.05). The median overall survival of patients with ND4 mutations and wt ND4 were all not reached. The median relapse-free survival were not reached and 29(2-53) months, respectively (P>0.05). There was no significance in the ratio of CR and RR patients between wt ND4 and ND4 mutated groups (P>0.05).

CONCLUSIONIt was concluded that novel ND4 mutations could be found in de novo AML patients, especially in patients with good karyotype. Thus, ND4 mutations might play an important role in AML prognosis. However, whether the mitochondria dysfunction contribute to leukemogenesis needs to be further investigated.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Child ; Female ; Humans ; Leukemia, Myeloid, Acute ; drug therapy ; genetics ; Male ; Middle Aged ; Mutation ; NADH Dehydrogenase ; genetics ; Prognosis ; Young Adult