Mechanism of catalpol regulating Th17 cell differentiation by interfering PKM2/LDHA expression / 中国药房

OBJECTIVE To investigate the mechanism of catalpol affecting the differentiation of helper T cell 17 （Th17） by interfering the expressions of pyruvate kinase M2 （PKM2） and lactate dehydrogenase A （LDHA）. METHODS The naive CD4+ T cells were selected from the spleen of C57BL/6 mice， and were differentiated into Th17 cells by adding directional differentiation stimulants for 72 hours. At the same time， the cells were treated with 0 （directed control）， 20， 40 and 80 μg/mL catalpol. The flow cytometry was used to detect the proportion of Th17 cell differentiation in cells； the colorimetric method was adopted to detect the levels of pyruvate and lactate in cell culture supernatant； mRNA expressions of retinoid-related orphan nuclear receptor gamma t （RORγt）， PKM2 and LDHA were detected by qRT-PCR method； Western blot was used to detect the expression levels of PKM2， LDHA， signal transducer and activator of transcription 3 （STAT3）， and phosphorylated STAT3 （p-STAT3） proteins in cells. RESULTS Compared with the directed control group， after 72 hours of treatment with 20， 40， 80 μg/mL catalpol， the differentiation ratio of Th17 cells were decreased by 6.74%， 8.41%， 9.24%， and the levels of pyruvate and lactate in the cell culture supernatant， the mRNA expressions of PKM2， LDHA and RORγt as well as the protein expressions of PKM2 and LDHA and the phosphorylation of STAT3 were significantly reduced （P＜0.05）. CONCLUSIONS Catalpol can reduce the glycolysis level by down-regulating the expressions of PKM2 and LDHA， thereby inhibiting the differentiation of Th17 cells.

Expression of serum connective tissue growth factor, glyoxalase Ⅰ, pyruvate kinase M2 in endometrial carcinoma and its relationship with clinicopathological features / 中国医师进修杂志

Objective:To explore the expression of serum connective tissue growth factor (CTGF), glyoxalase Ⅰ (GLO-I) and pyruvate kinase M2 (PKM2) in endometrial cancer and their relationship with clinicopathological characteristics.Methods:A total of 96 endometrial cancer patients in Yuechi County People's Hospital from February 2015 to February 2017 were selected as the research group, 48 patients with endometrial hyperplasia during the same period were selected as the benign control group, and 48 patients with healthy physical examination during the same period were selected as the healthy control group. The serum levels of CTGF, GLO-Ⅰ, and PKM2 in the three groups were analyzed. The correlation between serum levels of CTGF, GLO-Ⅰ and PKM2 in the research group was analyzed, and the relationship between each serum index and clinicopathological characteristics was analyzed.Results:The levels of serum CTGF, GLO-Ⅰ and PKM2 in the research group were higher than those in the benign control group and healthy control group: (184.31 ± 37.14) μg/L vs. (110.45 ± 20.59), (17.28 ± 0.42) μg/L; (95.17 ± 16.56) pmol/L vs. (56.29 ± 10.14), (9.08 ± 0.66) pmol/L; (20.25 ± 6.13) μg/L vs. (13.11 ± 4.58), (9.05 ± 2.74) μg/L; and the levels of serum CTGF, GLO-Ⅰ and PKM2 in the benign control group were higher than those in the healthy control group, there were statistical differences ( P<0.05). The results of Pearson correlation analysis showed that the level of CTGF had positive correlation with GLO-Ⅰ and PKM2 ( r = 0.713, 0.741, P<0.05), and the level of GLO-Ⅰ had positive correlation with PKM2 ( r = 0.823, P<0.05). The results of Spearman correlation analysis showed that the levels of CTGF, GLO-Ⅰ, PKM2 had positive correlation with FIGO stage ( r = 0.609, 0.704, 0.721; P<0.05), myometrial invasion depth ( r = 0.753, 0.695, 0.719; P<0.05), lymph node metastasis ( r = 0.776, 0.744, 0.640; P<0.05); had negative correlation with the degree of differentiation ( r = - 0.711, - 0.720, - 0.668; P<0.05). Conclusions:Serum CTGF, GLO-I, PKM2 expression levels are abnormally elevated in patients with endometrial cancer, which are significantly related to multiple clinicopathological characteristics.

Shikonin induces hepatocellular carcinoma cell apoptosis by suppressing PKM2/PHD3/HIF-1α signaling pathway / 南方医科大学学报

OBJECTIVE@#To investigate the mechanism of shikonin-induced death of human hepatocellular carcinoma SMMC-7721 cells.@*METHODS@#Cultured SMMC-7721 cells and normal hepatocytes (L-02 cells) were treated with 4, 8, or 16 μmol/L shikonin, and the changes in cell viability was assessed using MTT assay. The levels of ATP and lactic acid in the cell cultures were detected using commercial kits. Co-immunoprecipitation and immunofluorescence staining were used to determine the relationship among pyruvate kinase M2 (PKM2), prolyl hydroxylase 3 (PHD3), and hypoxia-inducible factor-1α (HIF-1α). The expressions of PHD3, PKM2, HIF-1α, Bax, cleaved caspase-3, and Bcl-2 in SMMC-7721 cells were detected with Western blotting, and cell apoptosis was analyzed with annexin V-FITC/PI staining. The effects of RNA interference of PKM2 on PHD3 and HIF-1α expressions in SMMC-7721 cells were detected using Western blotting.@*RESULTS@#The IC50 of shikonin against SMMC-7721 and L-02 cells was 8.041 μmol/L and 31.75 μmol/L, respectively. Treatment with shikonin significantly inhibited the protein expressions of PKM2, HIF-1α and PHD3 and nuclear translocation of PKM2 and HIF-1α in SMMC-7721 cells. Coimmunoprecipitation and immunofluorescence staining confirmed that shikonin inhibited the formation of PKM2/PHD3/HIF-1α complex and significantly reduced the contents of lactic acid and ATP in SMMC-7721 cells (P < 0.05). The expressions of PHD3 and HIF-1α decreased significantly after PKM2 knockdown (P < 0.05). Shikonin treatment significantly increased the apoptosis rate, enhanced the expressions of Bax and cleaved caspase-3, and decreased Bcl-2 expression in SMMC-7721 cells (P < 0.05).@*CONCLUSIONS@#Shikonin induces apoptosis of SMMC-7721 cells possibly by inhibiting aerobic glycolysis through the PKM2/PHD3/HIF-1α signaling pathway to cause energy supply dysfunction in the cells.

Effect of PKM2 on Osteogenic and Adipogenic Differentiation of Bone Marrow Mesenchymal Stem Cells in Myeloma Bone Disease / 中国实验血液学杂志

OBJECTIVE@#To investigate the expression of pyruvate kinase M2 (PKM2) in bone marrow mesenchymal stem cells (BMSCs) in myeloma bone disease (MBD) and its effect on osteogenic and adipogenic differentiation of BMSCs.@*METHODS@#BMSCs were isolated from bone marrow of five patients with multiple myeloma (MM) (MM group) and five with iron deficiency anemia (control group) for culture and identification. The expression of PKM2 protein were compared between the two groups. The differences between osteogenic and adipogenic differentiation of BMSCs were assessed by using alkaline phosphatase (ALP) and oil red O staining, and detecting marker genes of osteogenesis and adipogenesis. The effect of MM cell line (RPMI-8226) and BMSCs co-culture on the expression of PKM2 was explored. Functional analysis was performed to investigate the correlations of PKM2 expression of MM-derived BMSCs with osteogenic and adipogenic differentiation by employing PKM2 activator and inhibitor. The role of orlistat was explored in regulating PKM2 expression, osteogenic and adipogenic differentiation of MM-derived BMSCs.@*RESULTS@#Compared with control, MM-originated BMSCs possessed the ability of increased adipogenic and decreased osteogenic differentiation, and higher level of PKM2 protein. Co-culture of MM cells with BMSCs markedly up-regulated the expression of PKM2 of BMSCs. Up-regulation of PKM2 expression could promote adipogenic differentiation and inhibit osteogenic differentiation of MM-derived BMSCs, while down-regulation of PKM2 showed opposite effect. Orlistat significantly promoted osteogenic differentiation in MM-derived BMSCs via inhibiting the expression of PKM2.@*CONCLUSION@#The overexpression of PKM2 can induce the inhibition of osteogenic differentiation of BMSCs in MBD. Orlistat can promote the osteogenic differentiation of BMSCs via inhibiting the expression of PKM2, indicating a potential novel agent of anti-MBD therapy.

Effect of PKM2 on proliferation and EMT of intrahepatic cholangiocarcinoma cells / 西安交通大学学报(医学版)

【Objective】 To investigate the expression of pyruvate kinase M2 (PKM2) in intrahepatic cholangiocarcinoma (ICC) and the effect of PKM2 on the proliferation and epithelial-to-mesenchymal transition (EMT) of ICC cells. 【Methods】 PKM2 expression was evaluated in ICC tissues and cell lines by Real-time quantitative reverse-transcription polymerase chain reaction (RT-PCR), and immunohistochemistry assays. In vitro, we knocked down PKM2 expression in ICC cell lines and investigated the biological function and the underlying mechanism of PKM2 in ICC. 【Results】 RT-PCR results showed that PKM2 was highly expressed in ICC (P<0.05). Moreover, PKM2 knockdown inhibited cell proliferation and the invasive capacities of ICC cells, and inhibited Wnt/ β-Catenin signaling, which subsequently regulated EMT signaling pathway in vitro. 【Conclusion】 PKM2 expression in cholangiocarcinoma is significantly higher than that in adjacent tissues. PKM2 can regulate EMT and invasion and metastasis of ICC via the Wnt/β-Catenin signal.

Diagnostic value of pyruvate kinase M2 gene for papillary thyroid carcinoma in fine-needle aspiration specimens / 中华内分泌代谢杂志

Objective To investigate the diagnostic value of pyruvate kinase M2 ( PKM2) gene expression in papillary thyroid carcinoma ( PTC). Methods Quantitative real-time PCR ( RT-qPCR) was used to detect the expression of PKM2 mRNA in benign thyroid nodules, PTC, and normal thyroid cells around nodules of fine-needle aspiration (FNA) specimens. Immunohistochemistry ( IHC) was used to detect the expression of PKM2 protein in thyroid tissue after thyroidectomy. The receiver operating characteristic curve was constructed to evaluate the diagnostic value of PKM2 in PTC. Results The expression of PKM2 mRNA was detectable in FNA specimens of thyroid nodules,higher in PTC than those in normal thyroid tissue and benign thyroid nodules (P<0.01). PKM2 expression level was correlated with diameter of PTC ( P<0.05) , but had no correlation with lymph node metastasis, BRAFV600E mutation, and American Joint Committe on Cancer( AJCC) stage ( P>0.05) . The expression level of PKM2 mRNA in FNA specimens of thyroid nodules was paralleled with the expression level of PKM2 protein in postoperation pathological tissues. The accuracy, sensitivity, specificity of PKM2 gene in the diagnosis of PTC were 62.8％, 46.9％, and 95.7％, respectively. The accuracy and sensitivity of PKM2 combined with BRAFV600E were increased to 87.6％and 83.7％. Conclusion Detection of PKM2 gene in FNA specimens is highly specific in the diagnosis of PTC, making it a valuable molecular marker for preoperative diagnosis. The combination of PKM2 and BRAFV600E detection shows a higher diagnosis efficiency.

A study of radiosensitizing effect of PKM2 silencing in lung adenocarcinoma cells and xenografts / 中华放射肿瘤学杂志

Objective To investigate the impacts of pyruvate kinase M2 isoform (PKM2) silencing on the radiosensitivity of lung adenocarcinoma cell line (A549 cells) and the radiation synergy of xenografts, and to explore their mechanisms. Methods Plasmid pshRNA?PKM2 for interference with PKM2 expression was transfected into A549 cells, and empty vector?transfected cells and untransfected cells were set as con?trols. The silencing efficiency of pshRNA?PKM2 and the expression level of microtubule?associated protein 1 light chain 3(LC3) were measured by Western blot assay. The radiosensitizing effects in A549 cells and xen?ografts after PKM2 silencing were determined by colony?forming assay and xenografts growth curves. Autoph?agy formation in A549 cells and xenografts was analyzed by transmission electron microscopy, and the ex?pression level of PKM2 in xenografts was measured by immunohistochemistry. Comparison between groups was made by Student′s t?test, and the body weights of nude mice and xenograft volumes were subjected to a?nalysis of variance for continuous variables. Results Stable A549 cell lines transfected with pshRNA?PKM2 were successfully produced. Transfection with pshRNA?PKM2 significantly down?regulated PKM2 expression in A549 cells and xenografts (P= 0?? 001;P= 0?? 000). The sensitizer enhancement ratios for A549 cells and xenografts were 1?? 47 and 2?? 00, respectively. Interference with PKM2 expression enhanced radiation?in duced autophagy formation and significantly increased the ratio of LC 3 ? II / I ( P= 0.000 1 ) . Conclusions Silencing of PKM2 expression may enhance the radiosensitivity of A549 cells and xenografts by regulation of autophagy, which holds promise for becoming an effective radiosensitizing target for non?small cell lung canc?er, but still needs to be confirmed by further studies.

Blockage of PKM2 expression by gene silencing enhances the radiosensitivity of human lung cancer A549 cells / 中华放射医学与防护杂志

Objective To explore the role of pyruvate kinase M2 (PKM2) siRNA in the radiosensitivity of human lung cancer A549 cells.Methods PKM2 siRNA was synthesized according to the coding sequence of PKM2 mRNA and then was transferred into A549 cells with lipofectamine.The expressions of PKM2 gene and protein was detected by RT-PCR and Western blot,respectively.The experiments were divided into PKM2 siRNA interference group,siRNA negative control group,and blank control group.The cells of each group were exposure to 6 MV X-rays in different dose.Radiosensitivity was evaluated by colony formation assay.Flow cytometry was applied to analyze cell cycle distribution and apoptosis.Data are representative of three independent experiments.Results Ccompared with blank control cells,the expressions of PKM2 gene and protein in the PKM2 siRNA transferred A549 cell was efficiently diminished (t =20.91,47.00,P ＜0.01) with inhibition rates of (70.27 ± 1.38)％ and (70.42 ± 1.18) ％,respectively.Compared with control,PKM2 siRNA transfection significantly decreased the D0,Dq,N and SF2 values (t =43.82,28.44,15.60,29.63,P ＜ 0.01) and hence yield a sensitization enhancement ratio (SER) of 1.27.In addition,the percentage of G2/M phase cells in the siRNA group and irradiated group were both significantly higher than that of the blank control group (t =8.35,27.87,P ＜ 0.01).The combined treatments of PKM2 siRNA interference and irradiation arrested more cells in the G2/M phase compared to either treatment alone.The apoptosis rate of siRNA group was not dramatically different from that of blank control group.The apoptosis rate of irradiation group was higher than that of blank control group (t =23.99,P ＜ 0.01),and the combined treatments of siRNA and irradiation enhanced the apoptotic rate compared to either treatment alone (t=9.42,65.21,P ＜ 0.01).Conclusions Specific blockage of PKM2 expression by gene silencing could enhance the sensitivity of human lung cancer A549 cells to radiotherapy in vitro,which may due to the cell cycle arrest and apoptosis induction after irradiation.

Silencing PKM2 by siRNA Inhibits Proliferation and Glycolysis of Human Gastric Adenocarcinoma Cell Line SGC-7901 / 胃肠病学

Background:Pyruvate kinase M2( PKM2 ),which is highly expressed in cancer cells,plays an important role in cancer cell growth and aerobic glycolysis and is a promising target for cancer therapy. Aims:To investigate the effect of silencing PKM2 by siRNA on proliferation,apoptosis,migration,invasion and glycolysis of gastric cancer cell line SGC-7901 cells. Methods:SGC-7901 cells were divided into three groups:non-transfectd SGC-7901 cells,SGC-7901 cells transfected with empty plasmid and SCG-7901 cellls transfected with PKM2 siRNA. Expression of PKM2 was detected by fluorescent quantitative PCR and Western blotting at mRNA and protein levels. Intracellular expression and distribution of PKM2 was determined by immunofluorescence. CCK-8 assay,flow cytometry,migration and invasion experiment were used to assess cell proliferation,apoptosis,migration and invasion,respectively. Western blotting was used to determine the expression of glucose transporter-1( Glut-1)and lactate dehydrogenase A( LDHA). Spectrophotometry was used to detect levels of extracellular glucose and lactic acid and intracellular lactate dehydrogenase( LDH). Results:Compared with non-transfected group and negative control( empty plasmid )group,PKM2 mRNA and protein expressions were significantly decreased in PKM2 siRNA plasmid transfected group(P<0. 05). Intracellular expression of PKM2 was markedly decreased in PKM2 siRNA cells. After transfected with PKM2 siRNA plasmid,cell proliferation,migration and invasion were significantly inhibited,and cell apoptosis was increased significantly( P<0. 05 ). Expressions of Glut-1 and LDHA were down-regulated in PKM2 silenced cells( P <0. 05 ). Glucose uptake,lactic acid production and LDH activities were significantly decreased in PKM2 silenced cells(P<0. 05). Conclusions:RNA interference targeting PKM2 gene inhibits PKM2 expression in human gastric adenocarcinoma cell line SGC-7901 cells,thereby inhibits cell proliferation and glycolysis.