PKCz restrains cancer cell transformation by inhibiting nutrient stress-induced metabolic reprogramming
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE42186 | GEO | 2013/01/01
SECONDARY ACCESSION(S): PRJNA179262
REPOSITORIES: GEO
Similar Datasets
Project description:Tumor cells utilize the so-called Warburg effect to allow for rapid proliferation with glucose as the main nutrient. We show here that, although PKCz is critical for that effect, its deficiency promotes the plasticity necessary for nutrient-stressed cancer cells to reprogram their metabolism to utilize glutamine through the serine biosynthetic pathway, empowering them to survive and proliferate in the absence of glucose. We show that PKCz deficiency enhances glutamine utilization and expression of two key enzymes of the pathway, PGHDGH and PSAT1, in cells cultured in the absence of glucose. The loss of PKCz in mice results in enhanced intestinal tumorigenesis and increased levels of these two metabolic enzymes, while patients with low levels of PKCz have a poor prognosis. Taken together, this suggests that PKCz is a critical metabolic tumor suppressor. SW480 cells were infected with lentivirus expressing PKCz RNA interference (shPKCz) and a control lentivirus (shNT). The elimination of endogenous PKCz with shPKCz transfection was >90% efficient. Cells transfected with shNT had unaltered levels of PKCz. To mimic the conditions of nutrient stress to which tumor cells are normally exposed, both cell types were initially seeded in DMEM with 10% FBS, and cultured without subsequent further media changes, which led to nutrient exhaustion over time. Total RNA was harvested from three independent biological replicates for shPKCz and shNT transfected cells.
2013-01-01 | E-GEOD-42186 | biostudies-arrayexpress
Project description:By a transcriptome analysis using RNA sequencing in H1299 cells, a non-small cell lung cancer cell line (NSCLC), we determined the response of lipogenic genes to absence vs. presence of glutamine (Gln) or glucose (Gluc). We found that neither glutamine nor glucose alone was able to activate the expression of genes regulating fatty acid and cholesterol synthesis, and uptake, including SREBF1, SREBF2, ACLY, ACACA, FASN, SCD1, HMGCR and LDLR, as compared to absence of both. And, activation of lipogenic genes required the presence of both glutamine and glucose, but SCAP gene expression was not affected by either glutamine or glucose. The RNA sequencing analysis in H1299 cells also confirmed that ammonia, similarly to glutamine, significantly activated the expression of genes controlling the fatty acid and cholesterol synthesis pathways as compared to glucose alone. This study detemines the intrinsic molecular connection between glutamine, glucose and lipid synthesis.
2022-04-30 | GSE199089 | GEO
Project description:Tumor cells rely on glutamine to fulfill their metabolic demands and sustain proliferation. The elevated consumption of glutamine can lead to intratumoral nutrient depletion, causing metabolic stress that has the potential to impact tumor progression. Here, we show that nutrient stress caused by glutamine deprivation leads to the induction of epithelial-mesenchymal transition (EMT) in pancreatic ductal adenocarcinoma (PDAC) cells. Mechanistically, we demonstrate that glutamine deficiency regulates EMT through the upregulation of the EMT master regulator Slug, a process that is dependent on both MEK/ERK signaling and ATF4. We find that Slug is required in PDAC cells for glutamine deprivation-induced EMT, cell motility and nutrient stress survival. Importantly, we decipher that Slug is associated with nutrient stress in PDAC tumors and is required for metastasis. These results delineate a novel role for Slug in the nutrient stress response and provide insight into how nutrient depletion might influence PDAC progression.
2020-05-20 | GSE150874 | GEO
Project description:Tumor cells rely on glutamine to fulfill their metabolic demands and sustain proliferation. The elevated consumption of glutamine can lead to intratumoral nutrient depletion, causing metabolic stress that has the potential to impact tumor progression. Here, we show that nutrient stress caused by glutamine deprivation leads to the induction of epithelial-mesenchymal transition (EMT) in pancreatic ductal adenocarcinoma (PDAC) cells. Mechanistically, we demonstrate that glutamine deficiency regulates EMT through the upregulation of the EMT master regulator Slug, a process that is dependent on both MEK/ERK signaling and ATF4. We find that Slug is required in PDAC cells for glutamine deprivation-induced EMT, cell motility and nutrient stress survival. Importantly, we decipher that Slug is associated with nutrient stress in PDAC tumors and is required for metastasis. These results delineate a novel role for Slug in the nutrient stress response and provide insight into how nutrient depletion might influence PDAC progression.
2020-05-20 | GSE150873 | GEO
Project description:T cell fate and function is closely related to nutrient uptake and utilization. Here we demonstrate that glutamine deprivation switch Th17 cells to Treg cells in a time and dose dependent manner. The finding highlight the critical role of glutamine in T cell fate determination through a metabolic-epigenetic axis. We performed microarrays to explore the gene expression pattern of TH17 cells in the presence or absence of glutamine.
2024-02-09 | GSE166430 | GEO
Project description:Numerous mechanisms to support cells under conditions of transient nutrient starvation have been described. The tumor suppressor protein p53 can contribute to the adaptation of cells to metabolic stress through various mechanisms that may help cancer cell survival in nutrient limiting conditions. We show here that p53 helps cancer cells to survive glutamine starvation by promoting the expression of SLC1A3, an aspartate/glutamate transporter that allows the utilization of aspartate to support cells in the absence of extracellular glutamine. Under glutamine deprivation, SLC1A3 expression maintains electron transport chain and tricarboxylic acid cycle activity, promoting de novo glutamate, glutamine and nucleotide synthesis to rescue cell viability. Tumor cells with high levels of SLC1A3 expression are resistant to glutamine starvation and SLC1A3 depletion retards the growth of these cells in vitro and in vivo, suggesting a therapeutic potential for SLC1A3 inhibition.
2018-06-28 | GSE116087 | GEO
Project description:In addition to supporting increased cellular metabolism for untethered neoplastic growth, recent reports have indicated that certain metabolic enzymes may exhibit alternative functions in human cancers. Despite the ability to import serine from the microenvironment, lung tumors significantly elevate expression of biosynthetic enzymes responsible for the de novo production of serine, notably phosphoserine aminotransferase 1 (PSAT1). Highlighting the relevance of PSAT1 in lung cancer, patients with increased expression demonstrated poorer overall survival, so characterizing its role in lung tumor progression may ultimately identify different therapeutic strategies targeting this disease. Our preliminary studies now demonstrate a potential alternative function, beyond serine synthesis, of PSAT1 in lung tumor cells. Specifically, we found that PSAT1 localizes to the nucleus upon epidermal growth factor stimulation [via activating EGFR mutation (PC9, inhibited by the EGFR-mutant specific inhibitor, Erlotinib) or EGF stimulation (A549, EGFR-WT)] and regulates the nuclear import of pyruvate kinase M2 (PKM2). Importantly, nuclear PKM2 has been demonstrated to directly phosphorylate histones and modify gene transcription. In further support of this functional interaction, within yeast, PKM2 association with serine synthetic enzymes resulted in pervasive chromatin remodeling and alteration in global gene expression. Therefore, our objective in this proposal is to define gene signatures promoted by PSAT1-mediated nuclear PKM2 translocation in response to EGF-signaling in human lung cancer cells.
2024-04-23 | GSE173270 | GEO
Project description:The MondoA transcription factor forms a heterocomplex with its obligate partner Mlx to regulate ~75% of glucose-dependent transcription. By mediating glucose-induced activation of thioredoxin-interacting protein (TXNIP), MondoA directly represses glucose uptake. Given the predominant role of MondoA in controlling glucose-dependent transcription and glucose uptake, we asked whether glutamine regulates MondoA activity. Expression profiles from glucose and glutamine starved BxPC-3 cells (-G-Q) were compared with those from cells grown in glucose only (+G-Q), glutamine only (-G+Q) or glucose plus glutamine (+G+Q). As expected, TXNIP expression was highly induced by glucose. However, the addition of glutamine repressed the glucose-dependent induction of TXNIP. We show that glutamine inhibits MondoA-dependent transcriptional activation of TXNIP by triggering the recruitment of a histone deacetylase-dependent corepressor to the amino terminus of MondoA. Consistent with the repression of TXNIP, glucose uptake is elevated in cells grown in the presence of glucose and glutamine. Finally, alpha-ketoglutarate, a tricarboxylic acid cycle intermediate, also blocks MondoA-dependent activation of TXNIP and stimulates glucose uptake. Together, these results suggest that glutamine-dependent mitochondrial anapleurosis stimulates glucose uptake by restricting TXNIP expression via MondoA:Mlx complexes.
2009-08-17 | GSE17632 | GEO
Project description:The ability to adapt to varying nutrient availability in changing environments is critical for successful parasitism. The lifecycle stages of the African trypanosome, Trypanosoma brucei, that infect the host mammalian bloodstream utilize glucose exclusively for ATP production. The finding that trypanosomes also inhabit other tissues that frequently contain lower glucose concentrations suggests blood stage parasites may have to respond to a dynamic environment with changing nutrient availability in order to survive. However, little is known about how the parasites coordinate gene expression with nutrient availability. Through transcriptome analysis, we have found blood stage parasites deprived of glucose alter gene expression in a pattern similar to transcriptome changes triggered by other stresses. A surprisingly low concentration of glucose (<10 μM) was required to initiate the response. To further understand the dynamic regulation of gene expression that occurs in response to altered glucose availability in the environment, we have interrogated the 3’UTR of cytochrome c oxidase subunit VI, a known lifecycle stage regulated gene, and have identified a stem-loop structure that confers glucose-responsive regulation at the translational level.
2020-05-01 | GSE114395 | GEO
Project description:CTP synthase (CTPS) forms compartmentalized filaments in response to substrate availability and environmental nutrient status. However, the physiological role of filaments and mechanisms for filament assembly are not well understood. Here, we provide evidence that CTPS forms filaments in response to histidine influx during glutamine starvation. CTPS protein levels remained stable in the presence of histidine during nutrient deprivation, followed by rapid cell growth following nutrient replenishment. Tetramer conformation-based filament formation restricted CTPS enzyme activity duringnutrient deprivation. Furthermore, we demonstrated that filament formation controlled at two levels. Starvation stress/glutamine deficiency activates the GCN2/ATF4/MTHFD2 axis to accelerate the folate cycle in mitochondria for energy homeostasis. In addition, histidine promotes re-methylation of homocysteine by donating one-carbon to the cytosolic folate cycle. CTPS filament formation induced by histidine-mediated methylation maybe a strategy usedby cancer cells to maintain homeostasis and ensure a growth advantage in adverse environments.
2018-08-29 | GSE105251 | GEO