scholarly journals IDH1R132H Mutation Inhibits the Proliferation and Glycolysis of Glioma Cells by Regulating the HIF-1α/LDHA Pathway

Author(s):  
Hailong Li ◽  
Shuwei Wang ◽  
Yonggang Wang

Abstract Background: This study aims to explore the role and underlying mechanism of the IDH1R132H in the growth, migration, and glycolysis of glioma cells.Methods: The alternation of IDH1, HIF-1α, and LDHA genes in 283 LGG sample (TCGA LGG database) was analyzed on cBioportal. The expression of these three genes in glioma tissues with IDH1R132H mutation or IDH1 wild type (IDH1-WT) and normal brain tissues was also assessed using immunohistochemistry assay. In addition, U521 glioma cells were transfected with IDH1-WT or IDH1R132H to explore the role of IDH1 in the proliferation and migration of glioma cells in vitro. Cell growth curve, Transwell mitigation assay, and assessment of glucose consumption and lactate production were conducted to evaluate the proliferation, migration, and glycolysis of glioma cells.Results: The expression of HIF-1α and LDHA in IDH1R132H mutant was significantly lower than that in glioma cells with wild type IDH1 (P<0.05). IDH1R132H inhibited the proliferation and glycolysis of U521 glioma cells.Conclusion: The IDH1 mutation IDH1R132H plays an important role in the occurrence and development of glioma through inhibiting the expression of HIF-1α and glycolysis.

2021 ◽  
Vol 22 (4) ◽  
pp. 1825
Author(s):  
Li Hao ◽  
Aaron J. Marshall ◽  
Lixin Liu

Bam32 (B cell adaptor molecule of 32 kDa) functions in the immune responses of various leukocytes. However, the role of neutrophil Bam32 in inflammation is entirely unknown. Here, we determined the role of Bam32 in chemokine CXCL2-induced neutrophil chemotaxis in three mouse models of neutrophil recruitment. By using intravital microscopy in the mouse cremaster muscle, we found that transmigrated neutrophil number, neutrophil chemotaxis velocity, and total neutrophil chemotaxis distance were increased in Bam32−/− mice when compared with wild-type (WT) mice. In CXCL2-induced mouse peritonitis, the total emigrated neutrophils were increased in Bam32−/− mice at 2 but not 4 h. The CXCL2-induced chemotaxis distance and migration velocity of isolated Bam32−/− neutrophils in vitro were increased. We examined the activation of small GTPases Rac1, Rac2, and Rap1; the levels of phospho-Akt2 and total Akt2; and their crosstalk with Bam32 in neutrophils. The deficiency of Bam32 suppressed Rap1 activation without changing the activation of Rac1 and Rac2. The pharmacological inhibition of Rap1 by geranylgeranyltransferase I inhibitor (GGTI298) increased WT neutrophil chemotaxis. In addition, the deficiency of Bam32, as well as the inhibition of Rap1 activation, increased the levels of CXCL2-induced Akt1/2 phosphorylation at Thr308/309 in neutrophils. The inhibition of Akt by SH-5 attenuated CXCL2-induced adhesion and emigration in Bam32−/− mice. Together, our results reveal that Bam32 has a suppressive role in chemokine-induced neutrophil chemotaxis by regulating Rap1 activation and that this role of Bam32 in chemokine-induced neutrophil recruitment relies on the activation of PI3K effector Akt.


2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Weixing Dai ◽  
Xianke Meng ◽  
Shaobo Mo ◽  
Wenqiang Xiang ◽  
Ye Xu ◽  
...  

Abstract Background Low expression of FOXE1, a member of Forkhead box (FOX) transcription factor family that plays vital roles in cancers, contributes to poor prognosis of colorectal cancer (CRC) patients. However, the underlying mechanism remains unclear. Materials and methods The effects of FOXE1 on the growth of colon cancer cells and the expression of glycolytic enzymes were investigated in vitro and in vivo. Molecular biological experiments were used to reveal the underlying mechanisms of altered aerobic glycolysis. CRC tissue specimens were used to determine the clinical association of ectopic metabolism caused by dysregulated FOXE1. Results FOXE1 is highly expressed in normal colon tissues compared with cancer tissues and low expression of FOXE1 is significantly associated with poor prognosis of CRC patients. Silencing FOXE1 in CRC cell lines dramatically enhanced cell proliferation and colony formation and promoted glucose consumption and lactate production, while enforced expression of FOXE1 manifested the opposite effects. Mechanistically, FOXE1 bound directly to the promoter region of HK2 and negatively regulated its transcription. Furthermore, the expression of FOXE1 in CRC tissues was negatively correlated with that of HK2. Conclusion FOXE1 functions as a critical tumor suppressor in regulating tumor growth and glycolysis via suppressing HK2 in CRC.


1998 ◽  
Vol 111 (15) ◽  
pp. 2189-2195 ◽  
Author(s):  
X. Huang ◽  
J. Wu ◽  
S. Spong ◽  
D. Sheppard

The integrin alphavbeta6 is expressed on a variety of epithelial cells during dynamic processes including organogenesis, tissue injury and malignant transformation. However, because of the lack of tools to specifically inhibit the function of this integrin, little is known about its effects on cell behavior. To directly examine the role of this integrin in cell migration, we used keratinocytes derived from wild-type mice or mice expressing a null mutation in the beta6 subunit (beta6-/-) to perform migration assays in vitro. Migration on the known alphavbeta6 ligand, fibronectin was reduced in keratinocytes from beta6-/- mice. Interestingly, keratinocytes from beta6-/- mice also demonstrated markedly reduced migration on vitronectin, a protein not previously known to be a ligand for alphavbeta6. An anti-alphavbeta6 monoclonal antibody 10D5, generated by immunization of beta6-/- mice with murine keratinocytes, inhibited adhesion and migration of wild-type keratinocyte on both vitronectin and fibronectin to levels similar to those seen with keratinocytes from beta6-/- mice. alphavbeta6-mediated migration on both ligands was dramatically augmented by treatment with phorbol myrisate acetate (PMA) or with hepatocyte growth factor, and augmentation of migration by either stimulus could be abolished by the PKC inhibitor GF109203X, suggesting a critical role for PKC in enhancement of alphavbeta6-mediated cell migration.


Author(s):  
Shujie Li ◽  
Dingyi Yang ◽  
Furong Wu ◽  
Wei Zhou ◽  
Yue Xie ◽  
...  

IntroductionLincRNA-p21 was found to inhibit hepatic stellate cell (HSC) activation and liver fibrosis via a signaling cascade of lincRNA-p21-miR-181b-PTEN. Hypoxia was also previously proved to regulate hepatocellular carcinoma (HCC) glycolysis by targeting HK2.Material and methodsLuciferase assay was carried out to examine the regulatory role of miR-181b in lincRNA-p21 and HK2 expression. Quantitative real-time PCR was performed to measure the expression of lincRNA-p21, miR-181b and HK2 mRNA. Western blot and immunohistochemistry were used to analyze the expression of HK2 protein.ResultsThe expression of lincRNA-p21 and HK2 was effectively suppressed by miR-181b in Hep3B and HepG2 cells. Besides, the luciferase activities of wild type lincRNA-p21 and HK2 were remarkably suppressed by miR-181b in Hep3B and HepG2 cells. Activation and suppression of lincRNA-p21 expression using pcDNA and shRNA revealed a negative correlation between miR-181b and lincRNA-p21 expression as well as a positive correlation between HK2 and lincRNA-p21 expression. Moreover, lincRNA-p21 shRNA could effectively reverse the effect of hypoxia-induced dysregulation in miR-181b and HK2 expression, as well as the altered levels of glucose consumption and lactate production in Hep3B and HepG2 cells. Furthermore, lincRNA-p21 was capable of altering the growth and miR-181b/HK2 expression of HepG2 xenograft tumors in nude mice.ConclusionsOur study investigated the molecular relationship between lincRNA-p21, miR-181b and HK2 in cellular and animal models, and validated that hypoxia could up-regulate the expression level of lincRNA-p21 in the microenvironment of solid hepatocellular carcinoma tumor, which accordingly led to aggravated glycolysis via elevated HK2 expression, thus inhibiting the apoptosis of HCC.


Author(s):  
Zhandong Zhang ◽  
Wei Yang ◽  
Ning Li ◽  
Xiaobin Chen ◽  
Fei Ma ◽  
...  

Abstract Long non-coding RNAs (lncRNAs) regulate a series of biological processes, and their anomalous expression exerts critical roles in progression of multiple malignancies, including colorectal cancer (CRC). The present study was designed to provide new ideas and perspectives for the role of lncRNA MCF2L-AS1 and disclose the underlying mechanism in CRC. Herein, we observed that MCF2L-AS1 expression was enriched in CRC tissues and cell lines. Additionally, silencing of MCF2L-AS1 dramatically impeded cell proliferation, invasion and migration capacities of CRC, and distinctly attenuated the expression of invasion associated targets MMP-2 and MMP-9. Moreover, depletion of MCF2L-AS1 apparently restricted the glucose consumption and lactate production, and downregulated GLUT1 and LDHA expression. More importantly, we predicted and verified that MCF2L-AS1 acted as a molecular sponge for miR-874-3p and inversely regulated miR-874-3p expression. Interesting, FOXM1 was identified as direct target of miR-874-3p, and positively modulated by MCF2L-AS1 through sponging miR-874-3p. Mechanistically, MCF2L-AS1 accelerated cell proliferation, invasion and glycolysis through competitively binding to miR-874-3p, leading to enhance FOXM1 expression. Collectively, these outcomes highlighted that MCF2L-AS1 acted as a motivator by modulating the miR-874-3p/FOXM1 axis, thereby aggravating tumorigenesis and glycolysis progress of CRC, disclosing that MCF2L-AS1 may serve as a valuable and promising therapeutic strategy for CRC.


2020 ◽  
Vol 40 (6) ◽  
Author(s):  
Xinhui Fang ◽  
Yangqiu Bai ◽  
Lida Zhang ◽  
Songze Ding

Abstract Background: Gastric cancer (GC) is a malignant tumor of the digestive tract. Hypoxia plays an important role in the development of cancer, including GC. The present study aimed to investigate the role of circular RNA SLAMF6 (circSLAMF6) in the progression of GC under hypoxia. Methods: The expression of circSLAMF6, microRNA-204-5p (miR-204-5p) and myosin heavy chain 9 (MYH9) was measured by quantitative real-time polymerase chain reaction (qRT-PCR). GC cells were maintained under hypoxia (1% O2) for experiments in vitro. Glucose consumption and lactate production were determined by a Glucose Assay Kit and a Lactate Assay Kit, respectively. Levels of all protein were detected by Western blot. Cell migration and invasion were examined by Transwell assay. The interaction between miR-204-5p and circSLAMF6 or MYH9 was analyzed by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. Murine xenograft model was established to explore the role of circSLAMF6 in vivo. Results: CircSLAMF6 expression was increased in GC cells under hypoxia. Hypoxia promoted glycolysis, migration, and invasion in GC cells, which were reversed by circSLAMF6 knockdown. CircSLAMF6 was validated as a miR-204-5p sponge, and MYH9 was a target of miR-204-5p. Functionally, miR-204-5p inhibitor weakened the inhibition of circSLAMF6 knockdown on GC cell progression under hypoxia. Besides, MYH9 depletion suppressed glycolysis, migration, and invasion in GC cells under hypoxia. Importantly, circSLAMF6 deficiency inhibited tumor growth in vivo by regulating the miR-204-5p/MYH9 axis. Conclusion: CircSLAMF6 was involved in glycolysis, migration, and invasion by regulating the miR-204-5p/MYH9 axis in GC cells under hypoxia.


2021 ◽  
Vol 11 ◽  
Author(s):  
Xiang Li ◽  
Jiepeng Huang ◽  
Tingting Yu ◽  
Xiaoting Fang ◽  
Liqin Lou ◽  
...  

Background/AimsGrowing evidence supports the direct link of Fusobacterium nucleatum with colorectal cancer (CRC). However, to date, the underlying mechanism of action remains poorly understood. In this study, we examined the effects of F. nucleatum on the progression of CRC and investigated whether cyclin-dependent kinase 5 (Cdk5) is involved in the effect through activating the Wnt/β-catenin signaling pathway.Materials and MethodsCRC tissues and matched histologically normal specimens were collected from patients who were diagnosed with CRC and underwent surgical treatment in our hospital between January 2018 and January 2019. Two human CRC cell lines, including DLD-1 and SW480, were utilized mainly for in vitro mechanistic investigations.ResultsThe abundance of F. nucleatum was significantly greater in CRC tissues than in cancer-free specimens, which was significantly correlated with the progression of CRC. In vitro investigations revealed that F. nucleatum significantly enhanced the proliferation and migration of CRC cells. Furthermore, F. nucleatum significantly induced the expression of Cdk5 and activation of the Wnt/β-catenin signaling pathway. Notably, knockdown of Cdk5 significantly abrogated the effects of F. nucleatum on cellular processes and Wnt/β-catenin signaling in relation to the progression of CRC.ConclusionThe results of this study demonstrate that F. nucleatum orchestrates a molecular network involving the direct role of Cdk5 in activating Wnt/β-catenin signaling to modulate CRC progression. Thus, in-depth investigations of F. nucleatum-associated molecular pathways may offer valuable insight into the pathogenesis of CRC, which may help further the development of treatment for this disease.


1966 ◽  
Vol 51 (2) ◽  
pp. 193-202
Author(s):  
J. A. Antonioli ◽  
A. Vannotti

ABSTRACT 1. The metabolism of suspensions of circulating leucocytes has been studied after intramuscular injection of a dose of 50 mg/kg of a corticosteroid (cortisone acetate). The suspensions were incubated under aerobic conditions in the presence of a glucose concentration of 5.6 mm. Glucose consumption, lactate production, and variations in intracellular glycogen concentration were measured. After the administration of the corticosteroid, the anabolic processes of granulocyte metabolism were reversibly stimulated. Glucose consumption and lactate production increased 12 hours after the injection, but tended to normalize after 24 hours. The glycogen content of the granulocytes was enhanced, and glycogen synthesis during the course of the incubation was greatly stimulated. The action of the administered corticosteroid is more prolonged in females than in males. The injection of the corticosteroid caused metabolic modifications which resemble in their modulations and in their chronological development those found in circulating granulocytes of guinea-pigs suffering from sterile peritonitis. These results suggest, therefore, that, in the case of acute inflammation, the glucocorticosteroids may play an important role in the regulation of the metabolism of the blood leucocytes.


2020 ◽  
Vol 160 (11-12) ◽  
pp. 650-658
Author(s):  
Yichen Le ◽  
Yi He ◽  
Meirong Bai ◽  
Ying Wang ◽  
Jiaxue Wu ◽  
...  

Ajuba has been found to be mutated or aberrantly regulated in several human cancers and plays important roles in cancer progression via different signaling pathways. However, little is known about the role of Ajuba in hepatocellular carcinoma (HCC). Here, we found an upregulation of Ajuba expression in HCC tissues compared with normal liver tissues, while a poor prognosis was observed in HCC patients with high Ajuba expression. Knockout of Ajuba in HCC cells inhibited cell growth in vitro and in vivo, suppressed cell migration, and enhanced the cell apoptosis under stress. Moreover, re-expression of Ajuba in Ajuba-deficient cells could restore the phenotype of Ajuba-deficient cells. In conclusion, these results indicate that Ajuba is upregulated in HCC and promotes cell growth and migration of HCC cells, suggesting that Ajuba could possibly be a new target for HCC diagnosis and treatment.


2021 ◽  
Vol 11 (15) ◽  
pp. 6865
Author(s):  
Eun Seon Lee ◽  
Joung Hun Park ◽  
Seong Dong Wi ◽  
Ho Byoung Chae ◽  
Seol Ki Paeng ◽  
...  

The thioredoxin-h (Trx-h) family of Arabidopsis thaliana comprises cytosolic disulfide reductases. However, the physiological function of Trx-h2, which contains an additional 19 amino acids at its N-terminus, remains unclear. In this study, we investigated the molecular function of Trx-h2 both in vitro and in vivo and found that Arabidopsis Trx-h2 overexpression (Trx-h2OE) lines showed significantly longer roots than wild-type plants under cold stress. Therefore, we further investigated the role of Trx-h2 under cold stress. Our results revealed that Trx-h2 functions as an RNA chaperone by melting misfolded and non-functional RNAs, and by facilitating their correct folding into active forms with native conformation. We showed that Trx-h2 binds to and efficiently melts nucleic acids (ssDNA, dsDNA, and RNA), and facilitates the export of mRNAs from the nucleus to the cytoplasm under cold stress. Moreover, overexpression of Trx-h2 increased the survival rate of the cold-sensitive E. coli BX04 cells under low temperature. Thus, our data show that Trx-h2 performs function as an RNA chaperone under cold stress, thus increasing plant cold tolerance.


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