scholarly journals PIK3CAmutant tumors depend on oxoglutarate dehydrogenase

2017 ◽  
Vol 114 (17) ◽  
pp. E3434-E3443 ◽  
Author(s):  
Nina Ilic ◽  
Kıvanç Birsoy ◽  
Andrew J. Aguirre ◽  
Nora Kory ◽  
Michael E. Pacold ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Glucose Metabolism ◽  
Cancer Cell ◽  
Mutant Cell ◽  
Tca Cycle ◽  
Loss Of Function ◽  
Cycle Enzyme ◽  
Oxoglutarate Dehydrogenase ◽  
Mutant Cells ◽  
Malate Aspartate Shuttle

OncogenicPIK3CAmutations are found in a significant fraction of human cancers, but therapeutic inhibition of PI3K has only shown limited success in clinical trials. To understand how mutant PIK3CA contributes to cancer cell proliferation, we used genome scale loss-of-function screening in a large number of genomically annotated cancer cell lines. As expected, we found thatPIK3CAmutant cancer cells requirePIK3CAbut also require the expression of the TCA cycle enzyme 2-oxoglutarate dehydrogenase (OGDH). To understand the relationship between oncogenic PIK3CA and OGDH function, we interrogated metabolic requirements and found an increased reliance on glucose metabolism to sustainPIK3CAmutant cell proliferation. Functional metabolic studies revealed that OGDH suppression increased levels of the metabolite 2-oxoglutarate (2OG). We found that this increase in 2OG levels, either by OGDH suppression or exogenous 2OG treatment, resulted in aspartate depletion that was specifically manifested as auxotrophy withinPIK3CAmutant cells. Reduced levels of aspartate deregulated the malate–aspartate shuttle, which is important for cytoplasmic NAD+regeneration that sustains rapid glucose breakdown through glycolysis. Consequently, becausePIK3CAmutant cells exhibit a profound reliance on glucose metabolism, malate–aspartate shuttle deregulation leads to a specific proliferative block due to the inability to maintain NAD+/NADH homeostasis. Together these observations define a precise metabolic vulnerability imposed by a recurrently mutated oncogene.

scholarly journals LNCAROD enhances hepatocellular carcinoma malignancy by activating glycolysis through induction of pyruvate kinase isoform PKM2

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
Guizhi Jia ◽  
Yan Wang ◽  
Chengjie Lin ◽  
Shihui Lai ◽  
Hongliang Dai ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cell Proliferation ◽  
Pyruvate Kinase ◽  
Cancer Cell ◽  
Malignant Tumors ◽  
Aerobic Glycolysis ◽  
Cell Counting ◽  
Loss Of Function ◽  
Rna Immunoprecipitation

Abstract Background Mounting evidence has suggested the essential role of long non-coding RNAs (lncRNAs) in a plethora of malignant tumors, including hepatocellular carcinoma. However, the underlyling mechanisms of lncRNAs remain unidentified in HCC. The present work was aimed to explore the regulatory functions and mechanisms of LncRNA LNCAROD in HCC progression and chemotherapeutic response. Methods The expression of LNCAROD in HCC tissues and cell lines were detected by quantitative reverse transcription PCR (qPCR). Cancer cell proliferation, migration, invasion, and chemoresistance were evaluated by cell counting kit 8 (CCK8), colony formation, transwell, and chemosensitivity assays. Methylated RNA immunoprecipitation qRCR (MeRIP-qPCR) was used to determine N6-methyladenosine (m6A) modification level. RNA immunoprecipitation (RIP) and RNA pull down were applied to identify the molecular sponge role of LNCAROD for modulation of miR-145-5p via the competing endogenous RNA (ceRNA) mechanism, as well as the interaction between LNCAROD and serine-and arginine-rich splicing factor 3 (SRSF3). The interaction between insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) and LNCAROD was also identified by RIP assay. Gain- or-loss-of-function assays were used to identify the function and underlying mechanisms of LNCAROD in HCC. Results We found that LNCAROD was significantly upregulated and predicted a poorer prognosis in HCC patients. LNCAROD upregulation was maintained by increased m6A methylation-mediated RNA stability. LNCAROD significantly promoted HCC cell proliferation, migration, invasion, and chemoresistance both in vitro and in vivo. Furthermore, mechanistic studies revealed that pyruvate kinase isoform M2 (PKM2)-mediated glycolysis enhancement is critical for the role of LNACROD in HCC. According to bioinformatics prediction and our experimental data, LNCAROD directly binds to SRSF3 to induce PKM switching towards PKM2 and maintains PKM2 levels in HCC by acting as a ceRNA against miR-145-5p. The oncogenic effects of LNCAROD in HCC were more prominent under hypoxia than normoxia due to the upregulation of hypoxia-triggered hypoxia-inducible factor 1α. Conclusions In summary, our present study suggests that LNCAROD induces PKM2 upregulation via simultaneously enhancing SRSF3-mediated PKM switching to PKM2 and sponging miR-145-5p to increase PKM2 level, eventually increasing cancer cell aerobic glycolysis to participate in tumor malignancy and chemoresistance, especially under hypoxic microenvironment. This study provides a promising diagnostic marker and therapeutic target for HCC patients.

Glucose metabolism and bladder cancer.

2017 ◽  
Vol 35 (6_suppl) ◽  
pp. 359-359
Author(s):  
Eugene K. Lee ◽  
Karim Pirani ◽  
Jeffrey M. Holzbeierlein ◽  
Paige Martin ◽  
Parthasarathy Rangarajan ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Bladder Cancer ◽  
Glucose Metabolism ◽  
Cancer Cells ◽  
Glucose Concentration ◽  
Tca Cycle ◽  
Urine Samples ◽  
Pcr Array ◽  
Elisa Kit ◽  
Bladder Cancer Cells

359 Background: To understand and evaluate the role of glucose metabolism in bladder cancer growth, in the identification of disease, and development of potential treatment strategies. Methods: UMUC3, T24 and 253JBV cells were grown in varying glucose concentrations (25, 100 and 200mg/dl) and cell proliferation assay with Vi-Cell was performed. Next, we used Qiagen PCR array of glucose metabolic pathway of the UMUC3 cell line under different glucose concentrations. PKM2 is a driver of glycolysis and exists in an inactive dimer or active tetramer. Dimer PKM2 also known as Tumor M2-PK was measured in urine samples of bladder cancer patients using a commercially available ELISA kit (ScheBo Biotech AG). Lastly, Shikonin, a PKM2 inhibitor was evaluated as an inhibitor of bladder cancer cell proliferation using Vi-Cell. Results: Increased glucose concentration 200mg/dl leads to increased proliferation in bladder cancer cells while decreased concentration of glucose; 25mg/dl reduces proliferation compared to control (100). PCR array demonstrates genes in the glycolytic pathway genes are upregulated in cells that are grown in 200mg/dl glucose media and the TCA cycle genes are upregulated in cells that are subjected to the 25mg/dl glucose media when compared to control (100mg/dl). The enzyme pyruvate kinase M2 (PKM2) controls the transition from the glycolytic pathway to TCA cycle. We have found that 9/10 (90%) of bladder cancer urine samples show elevated levels of tumor M2-PK (>104) compared to urine from two normal subjects (~30 units ) using a commercially available ELISA kit. Conclusions: Increased glucose concentration 200mg/dl leads to increased proliferation in bladder cancer cells while decreased concentration of glucose; 25mg/dl reduces proliferation compared to control (100).

scholarly journals MAP kinase and autophagy pathways cooperate to maintain RAS mutant cancer cell survival

2019 ◽  
Vol 116 (10) ◽  
pp. 4508-4517 ◽  
Author(s):  
Chih-Shia Lee ◽  
Liam C. Lee ◽  
Tina L. Yuan ◽  
Sirisha Chakka ◽  
Christof Fellmann ◽  
...  
Keyword(s):  
Stress Response ◽  
Cell Lines ◽  
Cancer Cell ◽  
Mutant Cell ◽  
Small Gtpase ◽  
Therapeutic Window ◽  
Oncogenic Mutations ◽  
Cancer Cell Survival ◽  
Effector Pathways ◽  
Mutant Cells

Oncogenic mutations in the small GTPase KRAS are frequently found in human cancers, and, currently, there are no effective targeted therapies for these tumors. Using a combinatorial siRNA approach, we analyzed a panel ofKRASmutant colorectal and pancreatic cancer cell lines for their dependency on 28 gene nodes that represent canonical RAS effector pathways and selected stress response pathways. We found that RAF node knockdown best differentiatedKRASmutant andKRASWT cancer cells, suggesting RAF kinases are key oncoeffectors forKRASaddiction. By analyzing all 376 pairwise combination of these gene nodes, we found that cotargeting the RAF, RAC, and autophagy pathways can improve the capture ofKRASdependency better than targeting RAF alone. In particular, codepletion of the oncoeffector kinases BRAF and CRAF, together with the autophagy E1 ligase ATG7, gives the best therapeutic window betweenKRASmutant cells and normal, untransformed cells. Distinct patterns of RAS effector dependency were observed acrossKRASmutant cell lines, indicative of heterogeneous utilization of effector and stress response pathways in supporting KRAS addiction. Our findings revealed previously unappreciated complexity in the signaling network downstream of theKRASoncogene and suggest rational target combinations for more effective therapeutic intervention.

scholarly journals Hsa_circ_0000520 overexpression increases CDK2 expression via miR-1296 to facilitate cervical cancer cell proliferation

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Qingling Zheng ◽  
Jin Zhang ◽  
Ting Zhang ◽  
Yanxiang Liu ◽  
Xiuluan Du ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cervical Cancer ◽  
Cell Proliferation ◽  
Cancer Cell ◽  
Cell Cycle Progression ◽  
Cell Counting ◽  
Cervical Cancer Cell ◽  
Cancer Cell Proliferation ◽  
Loss Of Function ◽  
Tissue Samples

Abstract Background Circular RNA (circRNA) has been demonstrated to participate in cervical cancer development. In this study, we analyzed the role of hsa_circ_0000520 in cervical cancer. Methods Fifty-two pairs of cervical cancer and adjacent normal tissue samples were collected, and five human cervical cancer cell lines were obtained followed by the detection of hsa_circ_0000520 expression. Nuclear-cytoplasmic isolation and fluorescence in situ hybridization were performed to analyze the subcellular localization of hsa_circ_0000520 while linear RNA was digested by RNase R. Gain- or loss-of function experiments on hsa_circ_0000520 were performed, followed by detection of cell proliferation and cell cycle by EdU, Cell Counting Kit-8, colony formation assay, and flow cytometry respectively. Results Hsa_circ_0000520 and cyclin-dependent kinase 2 (CDK2) were highly expressed in cervical cancer tissues. Binding sites between microRNA-1296 (miR-1296) and hsa_circ_0000520 or CDK2 were verified. Antibody to Argonaute 2 (Ago2) could precipitate hsa_circ_0000520, indicating that hsa_circ_0000520 could competitively bind to miR-1296 via Ago2. Silencing hsa_circ_0000520 inhibited cervical cancer cell proliferation and promoted the inhibitory effects of miR-1296 on CDK2, thereby blocking cell cycle progression and promoting apoptosis. Conclusion These results support the premise that targeting hsa_circ_0000520 can be a potential approach to combat cervical cancer.

Genetic Impairment of Succinate Metabolism Disrupts Bioenergetic Sensing in Adrenal Neuroendocrine Cancer

2022 ◽  
Author(s):  
Priyanka Gupta ◽  
Keehn Strange ◽  
Rahul Telange ◽  
Ailan Guo ◽  
Heather Hatch ◽  
...  
Keyword(s):  
Tumor Progression ◽  
Warburg Effect ◽  
Tca Cycle ◽  
Tumor Formation ◽  
Metabolic Dysfunction ◽  
Loss Of Function ◽  
Amp Kinase ◽  
Cycle Enzyme ◽  
Energy Sensing

Metabolic dysfunction mutations can impair energy sensing and cause cancer. Loss of function of mitochondrial TCA cycle enzyme, succinate dehydrogenase B (SDHB) results in various forms of cancer typified by pheochromocytoma (PC). Here we delineate a signaling cascade where the loss of SDHB induces the Warburg effect in PC tumors, triggers dysregulation of Ca2+ homeostasis, and aberrantly activates calpain and the protein kinase Cdk5, through conversion of its cofactor from p35 to p25. Consequently, aberrant Cdk5 initiates a cascade of phospho-signaling where GSK3 inhibition inactivates energy-sensing by AMP-kinase through dephosphorylation of the AMP-kinase γ subunit, PRKAG2. Overexpression of p25-GFP in mouse adrenal chromaffin cells also elicits this phosphorylation signaling and causes PC tumor formation. A novel Cdk5 inhibitor, MRT3-007, reversed this phospho-cascade, invoking an anti-Warburg effect, cell cycle arrest, and senescence-like phenotype. This therapeutic approach halted tumor progression in vivo. Thus, we reveal an important novel mechanistic feature of metabolic sensing and demonstrate that its dysregulation underlies tumor progression in PC and likely other cancers.

scholarly journals A non-canonical role for glutamate decarboxylase 1 in cancer cell amino acid homeostasis, independent of the GABA shunt

2021 ◽  
Author(s):  
Bozena Samborska ◽  
Takla Griss ◽  
Eric H. Ma ◽  
Nicholas Jones ◽  
Kelsey S. Williams ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Cell Proliferation ◽  
Amino Acid ◽  
Cancer Cell ◽  
Glutamate Decarboxylase ◽  
Tca Cycle ◽  
Amino Acid Uptake ◽  
Acid Uptake ◽  
Gaba Shunt ◽  
Amino Acid Homeostasis

Glutamate decarboxylase 1 (GAD1) is best known for its role in producing the neurotransmitter γ-amino butyric acid (GABA) as part of the “GABA shunt” metabolic pathway, an alternative mechanism of glutamine anaplerosis for TCA cycle metabolism (Yogeeswari et al., 2005). However, understanding of the metabolic function of GAD1 in non-neuronal tissues has remained limited. Here, we show that GAD1 supports cancer cell proliferation independent of the GABA shunt. Despite its elevated expression in lung cancer tissue, GAD1 is not engaged in the GABA shunt in proliferating non-small cell lung cancer (NSCLC) cells, but rather is required for regulating amino acid homeostasis. Silencing GAD1 promotes a broad deficiency in amino acid uptake, leading to reduced glutamine-dependent TCA cycle metabolism and defects in serum- and amino acid-stimulated mTORC1 activation. Mechanistically, GAD1 regulates amino acid uptake through ATF4-dependent amino acid transporter expression including SLC7A5 (LAT1), an amino acid transporter required for branched chain amino acid (BCAA) uptake. Overexpression of LAT1 rescues the proliferative and mTORC1 signalling defects of GAD1-deficient tumor cells. Our results, therefore, define a non-canonical role for GAD1, independent of its characterised role in GABA metabolism, whereby GAD1 regulates amino acid homeostasis to maintain tumor cell proliferation.

NF-κB regulates colon cancer cell proliferation and tumorigenicity

2001 ◽  
Vol 120 (5) ◽  
pp. A615-A615
Author(s):  
S KUWADA ◽  
C SCAIFE ◽  
J KUANG ◽  
R DAYNES
Keyword(s):  
Colon Cancer ◽  
Cell Proliferation ◽  
Cancer Cell ◽  
Colon Cancer Cell ◽  
Cancer Cell Proliferation
Sign in / Sign up

Export Citation Format

Share Document