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Epidemiological and animal studies indicate that pre-existing diabetes increases the risk of Parkinson's disease(PD).However,the mechanisms underlying this association remain unclear.In the present study,we found that high glucose(HG)levels in the cerebrospinal fluid(CSF)of diabetic rats might enhance the effect of a subthreshold dose of the neurotoxin 6-hydroxydopamine(6-OHDA)on the development of motor disorders,and the damage to the nigrostriatal dopaminergic neuronal pathway.In vitro,HG promoted the 6-OHDA-induced apoptosis in PC12 cells differentiated to neurons with nerve growth factor(NGF)(NGF-PC12).Metabolomics showed that HG promoted hyperglycolysis in neurons and impaired tricarboxylic acid cycle(TCA cycle)activity,which was closely related to abnormal mito-chondrial fusion,thus resulting in mitochondrial loss.Interestingly,HG-induced upregulation of pyruvate kinase M2(PKM2)combined with 6-OHDA exposure not only mediated glycolysis but also promoted abnormal mitochondrial fusion by upregulating the expression of MFN2 in NGF-PC12 cells.In addition,we found that PKM2 knockdown rescued the abnormal mitochondrial fusion and cell apoptosis induced by HG+6-OHDA.Furthermore,we found that shikonin(SK),an inhibitor of PKM2,restored the mito-chondrial number,promoted TCA cycle activity,reversed hyperglycolysis,enhanced the tolerance of cultured neurons to 6-OHDA,and reduced the risk of PD in diabetic rats.Overall,our results indicate that diabetes promotes hyperglycolysis and abnormal mitochondrial fusion in neurons through the upre-gulation of PKM2,leading to an increase in the vulnerability of dopaminergic neurons to 6-OHDA.Thus,the inhibition of PKM2 and restoration of mitochondrial metabolic homeostasis/pathways may prevent the occurrence and development of diabetic PD.
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AIM: To investigate the function and mechanism of quercetin (Que) in anti-fibrosis in vitro and in vivo from the perspective of interfering with the glycolysis of renal interstitial fibroblasts. METHODS: ln vivo experiments, mice were administered in groups, kidneys were dissected, weighed and examined histopathologically and biochemically; ln vitro experiments, rat normal renal fibroblasts (NRK-49F cells) were treated with different reagents, proteins were extracted, and NRK-49F cell activation indicators such as α-smooth muscle actin (α-SMA) were detected by protein immunoblotting (Western Blot). The expression of the proteins, such as proliferating cell nuclear antigen (PCNA), was examined by protein immunoblotting (Western Blot), and the effect of Que on glucose uptake in NRK-49F cells induced by transforming growth factor-β (TGF-β1) and epidermal growth factor (EGF) was examined by fluorescence assay; the lactate content of cells in different experimental groups was examined by lactate assay kit; the effect of Que on glucose uptake in NRK-49F cells induced by TGF-β1 and EGF was examined by fluorescence quantitative PCR. EGF-induced mRNA of hexokinase (HK2), phosphofruc-tokinase 1 (PFK1) and muscle pyruvate kinase isozyme 2 (PKM2), key enzymes of glycolysis in NRK-49F cells. RESULTS: Compared with the UUO group, the morphological structures of kidney tissues in the Que administration group were all alleviated to different degrees, which were related to the inhibition of glycolysis, and the serum levels of urea nitrogen (BUN) and blood creatinine (Scr) in mice showed a significant downward trend; lactate production and glucose uptake in NRK-49F cells were gradually reduced, and Que affected TGF-β1 and EGF-induced RIF of mRNA levels of key enzymes of glycolysis gradually decreased and were associated with PKM2. CONCLUSION: Que inhibits PKM2 enzyme activity and glycolysis in NRK-49F cells and reduces TGF-β1-induced myofibroblast activation.
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Ischemic preconditioning (IPC) is a potential intervention known to protect the heart against ischemia/reperfusion injury, but its role in the no-reflow phenomenon that follows reperfusion is unclear. Dihydrotanshinone I (DT) is a natural compound and this study illustrates its role in cardiac ischemic injury from the aspect of IPC. Pretreatment with DT induced modest ROS production and protected cardiomyocytes against oxygen and glucose deprivation (OGD), but the protection was prevented by a ROS scavenger. In addition, DT administration protected the heart against isoprenaline challenge. Mechanistically, PKM2 reacted to transient ROS via oxidization at Cys423/Cys424, leading to glutathionylation and nuclear translocation in dimer form. In the nucleus, PKM2 served as a co-factor to promote HIF-1α-dependent gene induction, contributing to adaptive responses. In mice subjected to permanent coronary ligation, cardiac-specific knockdown of Pkm2 blocked DT-mediated preconditioning protection, which was rescued by overexpression of wild-type Pkm2, rather than Cys423/424-mutated Pkm2. In conclusion, PKM2 is sensitive to oxidation, and subsequent glutathionylation promotes its nuclear translocation. Although IPC has been viewed as a protective means against reperfusion injury, our study reveals its potential role in protection of the heart from no-reflow ischemia.
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Shugoshin-1 (SGOLl) is one of the human homologues of yeast Shugoshin that locates in the centromeric region. It prevents premature division of the eentromerie cohesin complex and maintaining chromosome stability. Very recently, the role of SGOLl in tumors has emerged, but its role in lung cancer is unclear. In this study, we identify that SGOLl was upregulated in lung cancer samples from the TCGA database (n=529, P< 0.00001), which was correlated to the overall survival time of lung cancer patients (P = 0.0049). Detected by qRT-PCR and Western blotting, we demonstrate that SGOLl was consistently upregulated in lung cancer cell lines than normal epithelial cell line. Regulatory effects of SGOLl on cell viability, clonality, migration and invasion of lung cancer cells A549 and NCI-H2405 were examined by Cell Counting Kit-8 (CCK8), Colony formation, Scratch and Transwell assays, respectively. Compared with the control group, knockdown of SGOLl significantly inhibited proliferation, migration and invasion in A549 and NCI-H2405 cells (P<0. 05). A positive correlation was identified between expression levels of pyruvate kinase muscle isoenzyme 2 (PKM2) and SGOLl in the TCGA data-base (r=0. 38, P = 0). Western blotting results showed that knockdown of SGOLl in A549 and NCI-H2405 cells down-regulated PKM2 as well. In addition, co-interventions of SGOLl and PKM2 were performed in A549 and NCI-H2405 cells to clarify the interaction mechanism between them. The results showed that overexpression of PKM2 in lung cancer cells could partially reverse the regulatory effects of SGOLl knockdown on proliferation, migration and invasion (P<0. 05). Therefore, our study showed that SGOLl promoted the proliferation, migration and invasion of lung cancer cells by regulating PKM2. This study provided a theoretical basis for the mechanism of SGOLl in lung cancer.
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Objective::To study the effect of Qingzao Jiufei Tang on the expression of key limiting enzymes hexokinase 2(HK2), phosphofructokinase 2(PFK2) and pyruvate kinase M2 (PKM2), and the glucose content in Lewis mice colon cancer cells. Method::A total of 50 male C57BL/6J mice were randomly divided into model group, chemotherapy group, and high, middle and low-dose Qingzao Jiufei Tang groups, with 10 mice in each group. The lung cancer cell model was established by injecting Lewis lung cancer cells into the right axilla. The high, middle and low dose groups were administered at the doses of 11, 5.5, 2.75 g·kg-1·d-1 for 2 weeks before modeling. The drug was administered through intraperitoneal injection at a dose of 50 mg·kg-1·(2 d)-1 in the chemotherapy group. The model group was intragastrically administered with an equal volume of normal saline. After the inoculation, the drug was administered for two weeks. Two weeks later, all of the mice were put to death, and tumor tissues were collected. The mRNA expression of HK2 was detected by Real-time PCR. the protein expression of PFK2 was detected by Western blot, the PKM2 activity was detected by enzyme-linked immunosorbent assay (ELISA). Result::Compared with the model group, mRNA expressions and activity of PKM2 in lung cancer cells of treatment groups were significantly declined, and glucose content increased significantly, with significant differences from those of model group (P<0.01). The PFK2 protein expressions in lung cancer cells of treatment groups (high, medium and low-dose groups) were significantly decreased (P<0.05, P<0.01). Conclusion::Qingzao Jiufei Tang could inhibit Lewis proliferation, and decrease the glucose intake in lung cancer cells. The effect targets may be the key rate-limiting enzymes HK2, PFK2, PKM2.
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Objective:To investigate the mechanism of Jianpi Yangzheng recipe in inhibiting aerobic glycolysis by down-regulating the expression of pyruvate kinase isoenzyme M2 (PKM2) protein, in order to promote apoptosis and inhibite epithelial-mesenchymal transition（EMT）in HCT116 cells of colorectal cancer. Method:The effect of different concentrations of Jianpi Yangzheng recipe on HCT116 cell proliferation was detected by methylthiazolyldiphenyl-tetrazolium bromide（MTT）colorimetry. Flow cytometry was used to detect the effect of different concentrations of Jianpi Yangzheng recipe（2.0, 4.0, 8.0 g·L-1） on HCT116 cell apoptosis. The effect of Jianpi Yangzheng recipe（2.0, 4.0, 8.0 g·L-1） on the migration and invasion ability of HCT116 cells was observed by cell scratch and cell invasion assay (Transwell). The effect of different concentrations of Jianpi Yangzheng recipe（2.0, 4.0, 8.0 g·L-1） on glycolysis metabolism of HCT116 cells were detected by lactic acid (LD) test kit and glucose assay kit, respectively. Western blot was used to detect the expressions of apoptosis-related proteins, like B lymphocyte tumor-2 gene (Bcl-2), Bcl-2 related X protein (Bax) and EMT-related proteins, like epithelial cadherin (E-cadherin)，neurogenic cadherin（N-cadherin）, Vimentin, and PKM2, the key protein of glycolysis, in each group. Result:MTT assay showed that, compared with the blank group, HCT116 cells were treated with Jianpi Yangzheng recipe for 48 h. With the increase of drug concentration, the inhibitory effect of Jianpi Yangzheng recipe on the proliferation of HCT116 cells was also increased; and when the concentration was 4.0 g·L-1, the inhibition rate of HCT116 cells was about 53.87%. Therefore, 2.0，4.0，8.0 g·L-1 were selected as low, medium and high-dose groups for the study. The cell flow cytometry results indicated that, compared with the blank group, the low, medium and high-dose groups all significantly induced the apoptosis of HCT116 cells (P<0.05), and the effect in inducing apoptosis was more obvious with the increase of drug concentration (P<0.05). Cell scratch and Transwell showed that, compared with the blank group, all the groups had an inhibitory effect on migration and invasion of HCT116 cells (P<0.05), and the effect was more significant with the increase of drug concentration (P<0.05). The determination of lactic acid and glucose indicated that compared with the blank group, with the increase of drug concentration, the amount of lactic acid produced by cells in each group gradually decreased (P<0.05), while the glucose dosage also gradually decreased (P<0.05). Western blot showed that, compared with the blank group, the protein expressions of E-cadherin and Bax were up-regulated in groups with different concentrations, whereas the protein expressions of N-cadherin, Vimentin, Bcl-2 and PKM2 were down-regulated (P<0.05). Conclusion:Jianpi Yangzheng recipe can effectively induce the apoptosis of HCT116 cells and inhibit EMT in colorectal cancer. The possible mechanism may be related to the inhibition of aerobic glycolysis pathway of HCT116 cells by down-regulating PKM2 protein expression.
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Background: Expressions of c-Myc and PKM2 are high in many tumors. However, studies on the regulation of mTOR/PKM2 and STAT3/c-Myc signaling pathways in gastric cancer are rare. Aims: To investigate the mechanism of crosstalk between mTOR/PKM2 and STAT3/c-Myc signaling pathways in regulating energy metabolism and acidic microenvironment of gastric cancer. Methods: Human gastric cancer AGS and HGC-27 cells were transfect with PKM2 and c-Myc lentivirus to construct cell models of knockdown of PKM2, c-Myc. CCK-8 assay was used to detect cell proliferation, cell migration was detected by Transwell chamber, cell apoptosis was determined by flow cytometry. The mRNA and protein expressions of PKM2, c-Myc, LDHA, STAT3, p-STAT3, and GLUT-1 were determined by real-time quantitative PCR and Western blotting, respectively. Lactic acid and glucose levels were detected by colorimetric method. Results: Expressions of PKM2 and c-Myc were up-regulated in gastric cancer. Knockdown of c-Myc could inhibit cell proliferation and migration, decrease protein expressions of LDHA, GLUT-1 and levels of glucose and lactic acid. The inhibition of gastric cancer was more obvious when both PKM2 and c-Myc were knockdown. mTOR/PKM2 signaling pathway was correlated to STAT3/c-Myc signaling pathway. Conclusions: PKM2 combined with c-Myc may be considered as a new therapeutic target for gastric cancer.
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Background: Studies have showed that proton pump inhibitor (PPI) can inhibit the expression of V-ATPases and influence the glycolysis of gastric cancer cells. V-ATPases have important significance on malignant biological behavior of tumor. Aims: To explore the mechanisms of PPI on gastric cancer via inhibiting glycolysis and glutamine metabolism. Methods: In the cell experiment, gastric cancer cell lines were cultured with PPI and knockdown of related molecules, cell proliferation was determined by CCK-8 assay, cell apoptosis was detected by flow cytometry. mRNA and protein expressions of related molecules were detected by quantitative PCR and Western blotting, respectively. In the animal experiment, nude mice were divided into blank control group, 0.9% NaCl solution group, pantoprazole sodium group, and PKM2 group, body weight, feeding behavior, tumor size and expressions of related pathway molecule in tumor tissue were compared. Results: PPI could inhibit the proliferation and induce apoptosis of gastric cancer cells. PPI could suppress the expression of related molecules of glycolysis and glutamine metabolism. Knocking down PKM2 or PI3K could inhibit proliferation and induce apoptosis of gastric cancer cells. Silencing V-ATPases inhibited the expression of related molecules of glycolysis and glutamine metabolism in gastric cancer cells. PPI therapy delayed tumor growth and reduced cachexia in tumor-bearing mice. Conclusions: PPI may inhibit cell proliferation and induce cell apoptosis by influencing glycolysis and glutamine metabolism of gastric cancer cells via suppressing V-ATPases and PI3K pathway, thus to play an anti-tumor role.
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Polypyrimidine tract-binding protein 1 (PTBP1) plays an essential role in splicing and is expressed in almost all cell types in humans, unlike the other proteins of the PTBP family. PTBP1 mediates several cellular processes in certain types of cells, including the growth and differentiation of neuronal cells and activation of immune cells. Its function is regulated by various molecules, including microRNAs (miRNAs), long non-coding RNAs (IncRNAs), and RNA-binding proteins. PTBP1 plays roles in various diseases, particularly in some cancers, including colorectal cancer, renal cell cancer, breast cancer, and glioma. In cancers, it acts mainly as a regulator of glycolysis, apoptosis, proliferation, tumorigenesis, invasion, and migration. The role of PTBP1 in cancer has become a popular research topic in recent years, and this research has contributed greatly to the formulation of a useful therapeutic strategy for cancer. In this review, we summarize recent findings related to PTBP1 and discuss how it regulates the development of cancer cells.
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Polypyrimidine tract-binding protein 1 (PTBP1) plays an essential role in splicing and is expressed in almost all cell types in humans, unlike the other proteins of the PTBP family. PTBP1 mediates several cellular processes in certain types of cells, including the growth and differentiation of neuronal cells and activation of immune cells. Its function is regulated by various molecules, including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and RNA-binding proteins. PTBP1 plays roles in various diseases, particularly in some cancers, including colorectal cancer, renal cell cancer, breast cancer, and glioma. In cancers, it acts mainly as a regulator of glycolysis, apoptosis, proliferation, tumorigenesis, invasion, and migration. The role of PTBP1 in cancer has become a popular research topic in recent years, and this research has contributed greatly to the formulation of a useful therapeutic strategy for cancer. In this review, we summarize recent findings related to PTBP1 and discuss how it regulates the development of cancer cells.
Subject(s)
Humans , Alternative Splicing , Carcinogenesis , Glycolysis , Heterogeneous-Nuclear Ribonucleoproteins/physiology , MicroRNAs/physiology , Neoplasms/pathology , Polypyrimidine Tract-Binding Protein/physiology , RNA, Long Noncoding/physiologyABSTRACT
A change in the metabolic flux of glucose from mitochondrial oxidative phosphorylation (OXPHOS) to aerobic glycolysis is regarded as one hallmark of cancer. However, the mechanisms underlying the metabolic switch between aerobic glycolysis and OXPHOS are unclear. Here we show that the M2 isoform of pyruvate kinase (PKM2), one of the rate-limiting enzymes in glycolysis, interacts with mitofusin 2 (MFN2), a key regulator of mitochondrial fusion, to promote mitochondrial fusion and OXPHOS, and attenuate glycolysis. mTOR increases the PKM2:MFN2 interaction by phosphorylating MFN2 and thereby modulates the effect of PKM2:MFN2 on glycolysis, mitochondrial fusion and OXPHOS. Thus, an mTOR-MFN2-PKM2 signaling axis couples glycolysis and OXPHOS to modulate cancer cell growth.
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Objective:To investigate the effect of PKM2 on proliferation and apoptosis of nasopharyngeal carcinoma cells.Methods:Nasopharyngeal carcinoma cell CNE-1 was transfected with PKM2 small interfering RNA (PKM2 siRNA1 and PKM2 siRNA2) and negative controls (siRNA control),the levels of PKM2 in the cells were detected by fluorescent quantitative PCR and Western blot,screening interference PKM2 siRNA2 continued to study.Cell proliferation was detected by MTT,cell cloning test showed the ability of cell cloning,apoptosis was detected by flow cytometry,ROS level was detected by DCFH-DA,the levels of p38MAPK,p-p38MAPK,C-myc,β-catenin,Cleaved Caspase-3 protein were detected by Western blot.Results:After transfection of PKM2 siRNA1 and PKM2 siRNA2,the levels of PKM2 mRNA and protein were significantly decreased compared with those without transfection,and after transfection of PKM2 siRNA2,the level of PKM2 in cells decreased more,the levels of PKM2 in transfected siRNA control cells were not significantly different from those without transfection.The rate of apoptosis after down-regulation of PKM2 expression increased from (9.36 ± 1.04)% to (48.42 ± 5.28)%,and the rate of cell clone formation decreased from (75.48 ± 8.25)% to (46.15 ± 3.47)%,OD values from (0.86±0.11) down to (0.52±0.04),elevated levels of ROS in cells,the levels of p-p38MAPK,Cleaved Caspase-3 proteins in cells were also significantly increased, the levels of C-myc and β-catenin in cells were obviously decreased.Conclusion:Downregulation of PKM2 expression inhibits nasopharyngeal carcinoma cell growth,promoting apoptosis of naso-pharyngeal carcinoma cells,the mechanism of action may be related to p38MAPK and Wnt/β-catenin signaling pathway.
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PURPOSE: The purpose of this study was to observe the effects of metformin on human esophageal cancer cell and to investigate its possible mechanisms. MATERIALS AND METHODS: Cell viability was detected by using a Cell Counting Kit-8, while cell cycle and apoptosis were assessed by flow cytometry and western blot was used to measure the expression of the related proteins. RNAi was used to knockout pyruvate kinase muscle isozyme 2 (PKM2). An Eca109 tumor model was established to evaluate the antitumor effect in vivo. Immunohistochemistry was determined based on the expression of PKM2 and Bim in tumor tissues. Tunnel was used to assess tumor cell apoptosis. RESULTS: Esophageal cancer cells viability was reduced after metformin treatment. The cell cycle was arrested in the G0/G1 phase, apoptosis was induced, caspase 3 was activated, caspase 9 was downregulated, and the pro-apoptotic protein Bim increased. Further study revealed that metformin could suppress the expression of insulin-like growth factor 1 receptor and its downstream proteins, phosphoinositide 3-kinase (PI3K), protein kinase B (AKT/PKB), phosphorylation of AKT (pAKT), mammalian target of rapamycin (mTOR), p70S6K, and PKM2. Insulin-like growth factor 1 partly reversed metfromin-induced apoptosis and attenuated the repression effect of metfomin to PI3K, pAKT, and PKM2. Knockout PKM2 resulted in the activation of caspase 3, down-regulation of caspase 9, and increased expression of Bim. In the Eca109 xenograft model, metformin significantly reduced tumor growth. Furthermore, we found that metformin treatment increased the rate of apoptosis, down-regulation of PKM2, and up-regulation of Bim in tumor tissues. CONCLUSION: Metformin restrained esophageal cancer cell proliferation partly by suppressing the PI3K/AKT/mTOR pathway.
Subject(s)
Humans , Apoptosis , Blotting, Western , Caspase 3 , Caspase 9 , Cell Count , Cell Cycle , Cell Proliferation , Cell Survival , Down-Regulation , Esophageal Neoplasms , Flow Cytometry , Heterografts , Immunohistochemistry , In Vitro Techniques , Metformin , Phosphorylation , Proto-Oncogene Proteins c-akt , Pyruvate Kinase , Repression, Psychology , Ribosomal Protein S6 Kinases, 70-kDa , RNA Interference , Sirolimus , Up-RegulationABSTRACT
PURPOSE: The purpose of this study was to observe the effects of metformin on human esophageal cancer cell and to investigate its possible mechanisms. MATERIALS AND METHODS: Cell viability was detected by using a Cell Counting Kit-8, while cell cycle and apoptosis were assessed by flow cytometry and western blot was used to measure the expression of the related proteins. RNAi was used to knockout pyruvate kinase muscle isozyme 2 (PKM2). An Eca109 tumor model was established to evaluate the antitumor effect in vivo. Immunohistochemistry was determined based on the expression of PKM2 and Bim in tumor tissues. Tunnel was used to assess tumor cell apoptosis. RESULTS: Esophageal cancer cells viability was reduced after metformin treatment. The cell cycle was arrested in the G0/G1 phase, apoptosis was induced, caspase 3 was activated, caspase 9 was downregulated, and the pro-apoptotic protein Bim increased. Further study revealed that metformin could suppress the expression of insulin-like growth factor 1 receptor and its downstream proteins, phosphoinositide 3-kinase (PI3K), protein kinase B (AKT/PKB), phosphorylation of AKT (pAKT), mammalian target of rapamycin (mTOR), p70S6K, and PKM2. Insulin-like growth factor 1 partly reversed metfromin-induced apoptosis and attenuated the repression effect of metfomin to PI3K, pAKT, and PKM2. Knockout PKM2 resulted in the activation of caspase 3, down-regulation of caspase 9, and increased expression of Bim. In the Eca109 xenograft model, metformin significantly reduced tumor growth. Furthermore, we found that metformin treatment increased the rate of apoptosis, down-regulation of PKM2, and up-regulation of Bim in tumor tissues. CONCLUSION: Metformin restrained esophageal cancer cell proliferation partly by suppressing the PI3K/AKT/mTOR pathway.
Subject(s)
Humans , Apoptosis , Blotting, Western , Caspase 3 , Caspase 9 , Cell Count , Cell Cycle , Cell Proliferation , Cell Survival , Down-Regulation , Esophageal Neoplasms , Flow Cytometry , Heterografts , Immunohistochemistry , In Vitro Techniques , Metformin , Phosphorylation , Proto-Oncogene Proteins c-akt , Pyruvate Kinase , Repression, Psychology , Ribosomal Protein S6 Kinases, 70-kDa , RNA Interference , Sirolimus , Up-RegulationABSTRACT
Objective To study the expression level of PKM1 and PKM2 in colorectal cancer tissue and explore the relationship between colorectal cancer progression and their expression level.Methods The PKM1 and PKM2 protein expression levels in colorectal cancer tissues and adjacent tissues to carcinoma were determined by Western blot and Immunohistochemisty method, and the relationship with colorectal cancer were discussed. Results Western blot and Immunohistochemisty results all showed that, compared with adjacent noncancerous, the protein level of PKM1 decreases significantly in cancer tissues (P<0.05), while the protein level of PKM2 increases significantly in cancer tissues (P<0.05).The protein level of PKM1 is not relative with age,sex and stage of patients, but the protein level of PKM2 is relative with pTNM(P<0.05).Conclusion Colorectal cancer tissues with low level of PKM1 and high level of PKM2, and PKM2 was related with TNM of patients.
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Objective:To investigate the expression level of pyruvate kinase M2 (PKM2) in tissues of non-small cell lung cancer (NSCLC) patients and the correlation between PKM2 expression level and radiation sensitivity. Methods:A total of 45 NSCLC pa-tients were chosen and treated with radiotherapy for two months after surgery. The patients were classified into four groups based on the curative effect. The mRNA expression levels of PKM2 in tumor and the homologous paraneoplastic tissues of NSCLC patients were de-tected prior to radiotherapy using real time-polymerase chain reaction (RT-PCR), and the protein expressions of PKM2 in the tumor and paraneoplastic tissues of NSCLC patients were detected with Western blot analysis and immunohistochemical method. The mRNA and protein expression levels of PKM2 in the tumor tissues of different groups were detected with RT-PCR and Western blot assays. Re-sults:The effective rate of radiotherapy for 2 months is 44.8%in NSCLC patients. The expression level of PKM2 is significantly high-er in tumor tissues than in homologous paraneoplastic tissues of NSCLC patients and is negatively correlated with the curative effect of radiotherapy. Conclusion:The expression level of PKM2 is significantly higher in tumor tissues than in the paraneoplastic tissues of NSCLC patients. Patients with lower PKM2 expression level are more sensitive to radiotherapy.
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Aim To investigate the roles of FFJ-5 in human breast cancer MCF7 cells and drug-resistant MCF7/DOX cells and to explore its mechanisms. Methods MTT assay was used to detect the effect of FFJ-5 on MCF7 and MCF7/DOX cell proliferation and sensitivity of doxorubicin in MCF7/DOX cells.West-ern blot was used to investigate the effect of FFJ-5 on expression of EGFR,p-EGFR,Akt,p-Akt,PKM2, cleaved caspase-3,cleaved PARP and P-gp.DNA lad-der analysis was performed to determine the effect of FFJ-5 on genomic DNA.RT-PCR was performed to de-tect the influence of FFJ-5 on multidrug resistance gene MDR1 mRNA levels.Results The results showed that FFJ-5 inhibited the growth of MCF7 ,inhibited the expression and activity of EGFR and Akt,and conse-quently reduced the expression of PKM2 in MCF7 cells;FFJ-5 activated caspase-3 and induced genomic DNA fragmentation;FFJ-5 also inhibited the growth of MCF7/DOX cells and enhanced the anti-tumor activity of doxorubicin in MCF7/DOX cells.Conclusion The results suggest that FFJ-5 could inhibit MCF7 cell growth and induce MCF7 cell apoptosis through inhibi-tion of EGFR-Akt-PKM2 pathway and activation of ap-optosis-related factors caspase-3 , meanwhile FFJ-5 could also reverse the resistance of MCF7/DOX.