RESUMO
Environmental nutrient availability influences T cell metabolism, impacting T cell function and shaping immune outcomes. Here, we identified ketone bodies (KBs)-including ß-hydroxybutyrate (ßOHB) and acetoacetate (AcAc)-as essential fuels supporting CD8+ T cell metabolism and effector function. ßOHB directly increased CD8+ T effector (Teff) cell cytokine production and cytolytic activity, and KB oxidation (ketolysis) was required for Teff cell responses to bacterial infection and tumor challenge. CD8+ Teff cells preferentially used KBs over glucose to fuel the tricarboxylic acid (TCA) cycle in vitro and in vivo. KBs directly boosted the respiratory capacity and TCA cycle-dependent metabolic pathways that fuel CD8+ T cell function. Mechanistically, ßOHB was a major substrate for acetyl-CoA production in CD8+ T cells and regulated effector responses through effects on histone acetylation. Together, our results identify cell-intrinsic ketolysis as a metabolic and epigenetic driver of optimal CD8+ T cell effector responses.
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Linfócitos T CD8-Positivos , Histonas , Ácido 3-Hidroxibutírico/metabolismo , Ácido 3-Hidroxibutírico/farmacologia , Acetilação , Histonas/metabolismo , Corpos Cetônicos , Animais , CamundongosRESUMO
Zhang et al. (2022) show that TCR signaling promotes the phosphorylation and activation of glycogen phosphorylase B (PYGB) in CD8+ memory T (Tmem) cells. PYGB-dependent glycogen mobilization provides a carbon source to support glycolysis and early Tmem cell recall responses.
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Glicogênio , Células T de Memória , Glicogênio/metabolismo , Glicólise , Transdução de SinaisRESUMO
Proteostasis requires oxidative metabolism (ATP) and mitigation of the associated damage by glutathione, in an increasingly dysfunctional relationship with aging. SLC3A2 (4F2hc, CD98) plays a role as a disulfide-linked adaptor to the SLC7A5 and SLC7A11 exchangers which import essential amino acids and cystine while exporting Gln and Glu, respectively. The positions of N-glycosylation sites on SLC3A2 have evolved with the emergence of primates, presumably in synchrony with metabolism. Herein, we report that each of the four sites in SLC3A2 has distinct profiles of Golgi-modified N-glycans. N-glycans at the primate-derived site N381 stabilized SLC3A2 in the galectin-3 lattice against coated-pit endocytosis, while N365, the site nearest the membrane promoted glycolipid-galectin-3 (GL-Lect)-driven endocytosis. Our results indicate that surface retention and endocytosis are precisely balanced by the number, position, and remodeling of N-glycans on SLC3A2. Furthermore, proteomics and functional assays revealed an N-glycan-dependent clustering of the SLC3A2∗SLC7A5 heterodimer with amino-acid/Na+ symporters (SLC1A4, SLC1A5) that balances branched-chain amino acids and Gln levels, at the expense of ATP to maintain the Na+/K+ gradient. In replete conditions, SLC3A2 interactions require Golgi-modified N-glycans at N365D and N381D, whereas reducing N-glycosylation in the endoplasmic reticulum by fluvastatin treatment promoted the recruitment of CD44 and transporters needed to mitigate stress. Thus, SLC3A2 N-glycosylation and Golgi remodeling of the N-glycans have distinct roles in amino acids import for growth, maintenance, and metabolic stresses.
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Cadeia Pesada da Proteína-1 Reguladora de Fusão , Transportador 1 de Aminoácidos Neutros Grandes , Estresse Fisiológico , Humanos , Trifosfato de Adenosina/metabolismo , Aminoácidos/metabolismo , Cadeia Pesada da Proteína-1 Reguladora de Fusão/metabolismo , Galectina 3/metabolismo , Glicosilação , Células HeLa , Transportador 1 de Aminoácidos Neutros Grandes/metabolismo , Polissacarídeos/metabolismoRESUMO
PURPOSE: To assess the role of multi-parametric MRI (mpMRI) in assessment of tumor response to fluvastatin administered prior to radical prostatectomy. METHODS: Men with MRI-visible, clinically significant prostate cancer and due to be treated with radical prostatectomy were prospectively enrolled. mpMRI was performed at baseline and following 6-7 week of neoadjuvant oral statin therapy (40 mg fluvastatin, twice daily), prior to prostatectomy. MRI assessment included tumor size, T2 relaxation time, ADC value, K-trans (volume transfer constant), Kep (reflux constant), and Ve (fractional volume) parameters at the 2 time points. Initial prostate needle biopsy cores, prior to starting oral statin therapy, corresponding to site of tumor on radical prostatectomy specimens were selected for analysis. The effect of fluvastatin on tumor proliferation (marker Ki67) and on tumor cell apoptosis (marker cleaved Caspase-3, CC3) were analyzed and correlated with MRI findings. RESULTS: Nine men with paired MRI studies were included in the study. Binary histopathological data was available for 6 of the participants. No significant change in tumor size (P = 0.898), T2 relaxation time (P = 0.213), ADC value (P = 0.455), K-trans (P = 0.613), Kep (P = 0.547) or Ve (P = 0.883) between the time of biopsy and prostatectomy were observed. No significant change in tumor proliferation (%Ki67-positive cells, P = 0.766) was observed by immunohistochemistry analysis. However, there was a significant increase in tumor cell apoptosis (%CC3-positive cells, P = 0.047). CONCLUSION: mpMRI techniques may not be sufficiently sensitive to detect the types (or magnitude) of tumor cell changes observed following 6-7 weeks of fluvastatin therapy for prostate cancer.
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Fluvastatina/uso terapêutico , Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/tratamento farmacológico , Administração Oral , Idoso , Estudos de Avaliação como Assunto , Fluvastatina/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Próstata/diagnóstico por imagem , Resultado do TratamentoRESUMO
Although the United States offers some of the most advanced psychological services in the world, not everyone in U.S. shares equally in these services, and health disparities persist when assessments do not appropriately measure different populations' mental health problems. To address this assessment issue, we conducted factor and Rasch analyses to assess the psychometric characteristics of the Brief Symptom Inventory-18 (BSI-18) to evaluate whether the BSI is culturally appropriate for assessing African Americans' psychological distress. The dimensional structure of the BSI was first identified and held up under cross-validation with a second subsample. The measure was unidimensional among African Americans. Our results also suggested minimal person separation, stability across subsamples, and little differential item functioning. Most African Americans identified themselves on the low end of the categories in a 0-4 rating scale, indicating their low endorsement of the items on the BSI. Rasch analyses were completed with the original scale but also collapsing the scale to three points, with some increase in separation and reliability for the collapsed scale. Differences in mean person position were found for mental health-related variables, consistent with hypotheses. Implications for theory and research on multicultural health scales are discussed as are effects of severe item skewness on analyses.
Assuntos
Competência Cultural , Inquéritos Epidemiológicos/métodos , Modelos Estatísticos , Psicometria/estatística & dados numéricos , Psicometria/normas , Adolescente , Adulto , Negro ou Afro-Americano , Assistência à Saúde Culturalmente Competente , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Adulto JovemRESUMO
Znf131 belongs to the family of POZ-ZF transcription factors, but, in contrast to most other characterized POZ-ZF proteins that function as transcriptional repressors, Znf131 acts as a transcriptional activator. Znf131 heterodimerizes with the POZ-ZF protein Kaiso, which itself represses a subset of canonical Wnt target genes, including the cell cycle regulator Cyclin D1. Herein, we report a possible role for Znf131 in Kaiso-mediated processes. Notably, we found that Znf131 associates with several Kaiso target gene promoters, including that of CCND1. ChIP analysis revealed that Znf131 indirectly associates with the CCND1 promoter in HCT116 and MCF7 cells via a region that encompasses the previously characterized +69 Kaiso Binding Site, hinting that the Znf131/Kaiso heterodimer may co-regulate Cyclin D1 expression. We also demonstrate that Kaiso inhibits Znf131 expression, raising the possibility that Kaiso and Znf131 act to fine-tune target gene expression. Together, our findings implicate Znf131 as a co-regulator of Kaiso-mediated biological processes.
Assuntos
Proteínas de Ligação a DNA/metabolismo , Mucosa Intestinal/metabolismo , Neoplasias Intestinais/metabolismo , Fatores de Transcrição/metabolismo , Animais , Regulação Neoplásica da Expressão Gênica , Células HT29 , Humanos , Fatores de Transcrição Kruppel-Like/metabolismo , Células MCF-7 , Camundongos , Proteínas de Xenopus/metabolismoRESUMO
Constitutive Wnt/ß-catenin signaling is a key contributor to colorectal cancer (CRC). Although inactivation of the tumor suppressor adenomatous polyposis coli (APC) is recognized as an early event in CRC development, it is the accumulation of multiple subsequent oncogenic insults facilitates malignant transformation. One potential contributor to colorectal carcinogenesis is the POZ-ZF transcription factor Kaiso, whose depletion extends lifespan and delays polyp onset in the widely used Apc(Min/+) mouse model of intestinal cancer. These findings suggested that Kaiso potentiates intestinal tumorigenesis, but this was paradoxical as Kaiso was previously implicated as a negative regulator of Wnt/ß-catenin signaling. To resolve Kaiso's role in intestinal tumorigenesis and canonical Wnt signaling, we generated a transgenic mouse model (Kaiso(Tg/+)) expressing an intestinal-specific myc-tagged Kaiso transgene. We then mated Kaiso(Tg/+) and Apc(Min/+) mice to generate Kaiso(Tg/+):Apc(Min/+) mice for further characterization. Kaiso(Tg/+):Apc(Min/+) mice exhibited reduced lifespan and increased polyp multiplicity compared to Apc(Min/+) mice. Consistent with this murine phenotype, we found increased Kaiso expression in human CRC tissue, supporting a role for Kaiso in human CRC. Interestingly, Wnt target gene expression was increased in Kaiso(Tg/+):Apc(Min/+) mice, suggesting that Kaiso's function as a negative regulator of canonical Wnt signaling, as seen in Xenopus, is not maintained in this context. Notably, Kaiso(Tg/+):Apc(Min/+) mice exhibited increased inflammation and activation of NFκB signaling compared to their Apc(Min/+) counterparts. This phenotype was consistent with our previous report that Kaiso(Tg/+) mice exhibit chronic intestinal inflammation. Together our findings highlight a role for Kaiso in promoting Wnt signaling, inflammation and tumorigenesis in the mammalian intestine.
RESUMO
Low oxygen tension (hypoxia) is a common characteristic of solid tumors and strongly correlates with poor prognosis and resistance to treatment. In response to hypoxia, cells initiate a cascade of transcriptional events regulated by the hypoxia inducible factor-1 (HIF-1) heterodimer. Since the oxygen-sensitive HIF-1α subunit is stabilized during hypoxia, it functions as the regulatory subunit of the protein. To date, while the mechanisms governing HIF-1α protein stabilization and function have been well studied, those governing HIF1A gene expression are not fully understood. However, recent studies have suggested that methylation of a HIF-1 binding site in the HIF1A promoter prevents its autoregulation. Here we report that the POZ-ZF transcription factor Kaiso modulates HIF1A gene expression by binding to the methylated HIF1A promoter in a region proximal to the autoregulatory HIF-1 binding site. Interestingly, Kaiso's regulation of HIF1A occurs primarily during hypoxia, which is consistent with the finding that Kaiso protein levels peak after 4 h of hypoxic incubation and return to normoxic levels after 24 h. Our data thus support a role for Kaiso in fine-tuning HIF1A gene expression after extended periods of hypoxia.
Assuntos
Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Proteínas de Neoplasias/fisiologia , Fatores de Transcrição/fisiologia , Neoplasias da Mama/genética , Hipóxia Celular/genética , Neoplasias do Colo/genética , Conjuntos de Dados como Assunto/estatística & dados numéricos , Feminino , Redes Reguladoras de Genes , Células HCT116 , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Regiões Promotoras Genéticas/genética , Transdução de Sinais , Transcrição GênicaRESUMO
OBJECTIVES: To evaluate for the first time, comparative serum and prostate tissue concentrations of lipophilic and hydrophilic statins. METHODS: After reviewing all patients who underwent radical prostatectomy between 1993-2019, we selected 80 patients taking atorvastatin (lipophilic) or rosuvastatin (hydrophilic) for cholesterol control and with available banked fresh-frozen tissue from the prostatectomy. Primary endpoint was serum and prostate statin concentration measured by HPLC-mass spectrometry analysis. Serum/prostate statin concentrations were compared between patients on atorvastatin and rosuvastatin, and patients receiving high- and low-dose statin, using the Mann-Whitney U test. RESULTS: In total, 39 patients were taking atorvastatin and 41 were taking rosuvastatin. Thirty-eight and 42 were taking high- and low-dose statin, respectively. Statin concentration was measurable in the prostatic tissue of 15 patients (38.4%) taking atorvastatin (33.3% high-dose vs. 42.8% low-dose) compared to 22 (53.6%) taking rosuvastatin (55% high-dose vs. 52.3% low-dose). Median tissue concentration of rosuvastatin was greater than atorvastatin (3.98 ng/g vs. 0.96 ng/g, p<0.001). Dose-dependency was observed: median prostate concentration was higher in those taking high-dose vs. low-dose statin for both atorvastatin (1.22 ng/g vs. 0.79 ng/g, p=0.69) and rosuvastatin (5.21 ng/g vs. 1.99 ng/g, p<0.001). CONCLUSIONS: We have shown, for the first time, that lipophilic and hydrophilic statins can be measured in the prostate of patients with prostate cancer and that the concentrations are dependent on dose. Moreover, rosuvastatin, a hydrophilic statin, achieves a 4-fold higher concentration in the prostate.
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Amino-terminal (Nt-) acetylation (NTA) is a common protein modification, affecting approximately 80% of all human proteins. The human essential X-linked gene, NAA10, encodes for the enzyme NAA10, which is the catalytic subunit in the N-terminal acetyltransferase A (NatA) complex. There is extensive genetic variation in humans with missense, splice-site, and C-terminal frameshift variants in NAA10. In mice, Naa10 is not an essential gene, as there exists a paralogous gene, Naa12, that substantially rescues Naa10 knockout mice from embryonic lethality, whereas double knockouts (Naa10-/Y Naa12-/-) are embryonic lethal. However, the phenotypic variability in the mice is nonetheless quite extensive, including piebaldism, skeletal defects, small size, hydrocephaly, hydronephrosis, and neonatal lethality. Here we replicate these phenotypes with new genetic alleles in mice, but we demonstrate their modulation by genetic background and environmental effects. We cannot replicate a prior report of "maternal effect lethality" for heterozygous Naa10-/X female mice, but we do observe a small amount of embryonic lethality in the Naa10-/Y male mice on the inbred genetic background in this different animal facility.
RESUMO
Amino-terminal (Nt-) acetylation (NTA) is a common protein modification, affecting approximately 80% of all human proteins. The human essential X-linked gene, NAA10, encodes for the enzyme NAA10, which is the catalytic subunit in the N-terminal acetyltransferase A (NatA) complex. There is extensive genetic variation in humans with missense, splice-site, and C-terminal frameshift variants in NAA10. In mice, Naa10 is not an essential gene, as there exists a paralogous gene, Naa12, that substantially rescues Naa10 knockout mice from embryonic lethality, whereas double knockouts (Naa10-/Y Naa12-/-) are embryonic lethal. However, the phenotypic variability in the mice is nonetheless quite extensive, including piebaldism, skeletal defects, small size, hydrocephaly, hydronephrosis, and neonatal lethality. Here we replicate these phenotypes with new genetic alleles in mice, but we demonstrate their modulation by genetic background and environmental effects. We cannot replicate a prior report of "maternal effect lethality" for heterozygous Naa10-/X female mice, but we do observe a small amount of embryonic lethality in the Naa10-/y male mice on the inbred genetic background in this different animal facility.
Assuntos
Camundongos Knockout , Acetiltransferase N-Terminal A , Acetiltransferase N-Terminal E , Animais , Acetiltransferase N-Terminal A/genética , Acetiltransferase N-Terminal A/metabolismo , Acetiltransferase N-Terminal E/genética , Acetiltransferase N-Terminal E/metabolismo , Camundongos , Feminino , Masculino , Fenótipo , Patrimônio Genético , Herança Materna/genética , Camundongos Endogâmicos C57BLRESUMO
Targeting programmed cell death protein 1 (PD-1) is an important component of many immune checkpoint blockade (ICB) therapeutic approaches. However, ICB is not an efficacious strategy in a variety of cancer types, in part due to immunosuppressive metabolites in the tumor microenvironment. Here, we find that αPD-1-resistant cancer cells produce abundant itaconate (ITA) due to enhanced levels of aconitate decarboxylase (Acod1). Acod1 has an important role in the resistance to αPD-1, as decreasing Acod1 levels in αPD-1-resistant cancer cells can sensitize tumors to αPD-1 therapy. Mechanistically, cancer cells with high Acod1 inhibit the proliferation of naive CD8+ T cells through the secretion of inhibitory factors. Surprisingly, inhibition of CD8+ T cell proliferation is not dependent on the secretion of ITA but is instead a consequence of the release of small inhibitory peptides. Our study suggests that strategies to counter the activity of Acod1 in cancer cells may sensitize tumors to ICB therapy.
Assuntos
Carboxiliases , Humanos , Animais , Linhagem Celular Tumoral , Carboxiliases/metabolismo , Camundongos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Peptídeos/metabolismo , Peptídeos/farmacologia , Neoplasias/imunologia , Neoplasias/patologia , Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Evasão da Resposta Imune , Camundongos Endogâmicos C57BLRESUMO
The progressive decline of CD8 T cell effector function-also known as terminal exhaustion-is a major contributor to immune evasion in cancer. Yet, the molecular mechanisms that drive CD8 T cell dysfunction remain poorly understood. Here, we report that the Kelch-like ECH-associated protein 1 (KEAP1)-Nuclear factor erythroid 2-related factor 2 (NRF2) signaling axis, which mediates cellular adaptations to oxidative stress, directly regulates CD8 T cell exhaustion. Transcriptional profiling of dysfunctional CD8 T cells from chronic infection and cancer reveals enrichment of NRF2 activity in terminally exhausted (Texterm) CD8 T cells. Increasing NRF2 activity in CD8 T cells (via conditional deletion of KEAP1) promotes increased glutathione production and antioxidant defense yet accelerates the development of terminally exhausted (PD-1+TIM-3+) CD8 T cells in response to chronic infection or tumor challenge. Mechanistically, we identify PTGIR, a receptor for the circulating eicosanoid prostacyclin, as an NRF2-regulated protein that promotes CD8 T cell dysfunction. Silencing PTGIR expression restores the anti-tumor function of KEAP1-deficient T cells. Moreover, lowering PTGIR expression in CD8 T cells both reduces terminal exhaustion and enhances T cell effector responses (i.e. IFN-γ and granzyme production) to chronic infection and cancer. Together, these results establish the KEAP1-NRF2 axis as a metabolic sensor linking oxidative stress to CD8 T cell dysfunction and identify the prostacyclin receptor PTGIR as an NRF2-regulated immune checkpoint that regulates CD8 T cell fate decisions between effector and exhausted states.
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Infusion of 13C-labeled metabolites provides a gold standard for understanding the metabolic processes used by T cells during immune responses in vivo. Through infusion of 13C-labeled metabolites (glucose, glutamine, and acetate) in Listeria monocytogenes-infected mice, we demonstrate that CD8 T effector (Teff) cells use metabolites for specific pathways during specific phases of activation. Highly proliferative early Teff cells in vivo shunt glucose primarily toward nucleotide synthesis and leverage glutamine anaplerosis in the tricarboxylic acid (TCA) cycle to support adenosine triphosphate and de novo pyrimidine synthesis. In addition, early Teff cells rely on glutamic-oxaloacetic transaminase 1 (Got1)-which regulates de novo aspartate synthesis-for effector cell expansion in vivo. CD8 Teff cells change fuel preference over the course of infection, switching from glutamine- to acetate-dependent TCA cycle metabolism late in infection. This study provides insights into the dynamics of Teff metabolism, illuminating distinct pathways of fuel consumption associated with CD8 Teff cell function in vivo.
Assuntos
Acetatos , Linfócitos T CD8-Positivos , Isótopos de Carbono , Glutamina , Glutamina/metabolismo , Animais , Linfócitos T CD8-Positivos/metabolismo , Acetatos/metabolismo , Camundongos , Listeriose/metabolismo , Listeriose/imunologia , Listeriose/microbiologia , Listeria monocytogenes , Ciclo do Ácido Cítrico , Glucose/metabolismo , Camundongos Endogâmicos C57BLRESUMO
Targeting PD-1 is an important component of many immune checkpoint blockade (ICB) therapeutic approaches. However, ICB is not an efficacious strategy in a variety of cancer types, in part due to immunosuppressive metabolites in the tumor microenvironment (TME). Here, we find that αPD-1-resistant cancer cells produce abundant itaconate (ITA) due to enhanced levels of aconitate decarboxylase (Acod1). Acod1 has an important role in the resistance to αPD-1, as decreasing Acod1 levels in αPD-1 resistant cancer cells can sensitize tumors to αPD-1 therapy. Mechanistically, cancer cells with high Acod1 inhibit the proliferation of naïve CD8+ T cells through the secretion of inhibitory factors. Surprisingly, inhibition of CD8+ T cell proliferation is not dependent on secretion of ITA, but is instead a consequence of the release of small inhibitory peptides. Our study suggests that strategies to counter the activity of Acod1 in cancer cells may sensitize tumors to ICB therapy.
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Growing evidence suggests that men prescribed a statin for cholesterol control have a lower risk of advanced prostate cancer (PCa) and improved treatment outcomes; however, the mechanism by which statins elicit their anti-neoplastic effects is not well understood and is likely multifaceted. Statins are potent and specific inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR), the rate-limiting enzyme of the mevalonate (MVA) metabolic pathway. This two-part series is a review of the observational and experimental data on statins as anti-cancer agents in PCa. In this article, we describe the functional role that deregulated MVA metabolism plays in PCa progression and summarize the biological evidence and rationale for targeting the MVA pathway, with statins and other agents, for the treatment of PCa.
Assuntos
Antineoplásicos , Inibidores de Hidroximetilglutaril-CoA Redutases , Neoplasias da Próstata , Masculino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Ácido Mevalônico/metabolismo , Ácido Mevalônico/farmacologia , Ácido Mevalônico/uso terapêutico , Antineoplásicos/uso terapêutico , ColesterolRESUMO
Statins, a family of FDA-approved cholesterol-lowering drugs that inhibit the rate-limiting enzyme of the mevalonate metabolic pathway, have demonstrated anticancer activity. Evidence shows that dipyridamole potentiates statin-induced cancer cell death by blocking a restorative feedback loop triggered by statin treatment. Leveraging this knowledge, we develop an integrative pharmacogenomics pipeline to identify compounds similar to dipyridamole at the level of drug structure, cell sensitivity and molecular perturbation. To overcome the complex polypharmacology of dipyridamole, we focus our pharmacogenomics pipeline on mevalonate pathway genes, which we name mevalonate drug-network fusion (MVA-DNF). We validate top-ranked compounds, nelfinavir and honokiol, and identify that low expression of the canonical epithelial cell marker, E-cadherin, is associated with statin-compound synergy. Analysis of remaining prioritized hits led to the validation of additional compounds, clotrimazole and vemurafenib. Thus, our computational pharmacogenomic approach identifies actionable compounds with pathway-specific activities.
Assuntos
Neoplasias da Mama , Inibidores de Hidroximetilglutaril-CoA Redutases , Humanos , Feminino , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Ácido Mevalônico/metabolismo , Farmacogenética , Vemurafenib/uso terapêutico , Nelfinavir/uso terapêutico , Clotrimazol/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Caderinas , Colesterol , DipiridamolRESUMO
How environmental nutrient availability impacts T cell metabolism and function remains poorly understood. Here, we report that the presence of physiologic carbon sources (PCSs) in cell culture medium broadly impacts glucose utilization by CD8+ T cells, independent of transcriptional changes in metabolic reprogramming. The presence of PCSs reduced glucose contribution to the TCA cycle and increased effector function of CD8+ T cells, with lactate directly fueling the TCA cycle. In fact, CD8+ T cells responding to Listeria infection preferentially consumed lactate over glucose as a TCA cycle substrate in vitro, with lactate enhancing T cell bioenergetic and biosynthetic capacity. Inhibiting lactate-dependent metabolism in CD8+ T cells by silencing lactate dehydrogenase A (Ldha) impaired both T cell metabolic homeostasis and proliferative expansion in vivo. Together, our data indicate that carbon source availability shapes T cell glucose metabolism and identifies lactate as a bioenergetic and biosynthetic fuel for CD8+ effector T cells.
Assuntos
Linfócitos T CD8-Positivos , Carbono , Linfócitos T CD8-Positivos/metabolismo , Carbono/metabolismo , Glucose/metabolismo , Ácido Láctico/metabolismo , NutrientesRESUMO
Aberrant N-glycan Golgi remodeling and metabolism are associated with epithelial-mesenchymal transition (EMT) and metastasis in patients with breast cancer. Despite this association, the N-glycosylation pathway has not been successfully targeted in cancer. Here, we show that inhibition of the mevalonate pathway with fluvastatin, a clinically approved drug, reduces both N-glycosylation and N-glycan-branching, essential components of the EMT program and tumor metastasis. This indicates novel cross-talk between N-glycosylation at the endoplasmic reticulum (ER) and N-glycan remodeling at the Golgi. Consistent with this cooperative model between the two spatially separated levels of protein N-glycosylation, fluvastatin-induced tumor cell death was enhanced by loss of Golgi-associated N-acetylglucosaminyltransferases MGAT1 or MGAT5. In a mouse model of postsurgical metastatic breast cancer, adjuvant fluvastatin treatment reduced metastatic burden and improved overall survival. Collectively, these data support the immediate repurposing of fluvastatin as an adjuvant therapeutic to combat metastatic recurrence in breast cancer by targeting protein N-glycosylation at both the ER and Golgi. SIGNIFICANCE: These findings show that metastatic breast cancer cells depend on the fluvastatin-sensitive mevalonate pathway to support protein N-glycosylation, warranting immediate clinical testing of fluvastatin as an adjuvant therapy for breast cancer.
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Neoplasias da Mama/tratamento farmacológico , Fluvastatina/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Ácido Mevalônico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Adjuvantes Imunológicos/farmacologia , Animais , Apoptose , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células , Retículo Endoplasmático/efeitos dos fármacos , Transição Epitelial-Mesenquimal , Feminino , Glicosilação , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Camundongos , Camundongos SCID , Prognóstico , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Multiple myeloma (MM) is a plasma cell malignancy that is often driven by chromosomal translocations. In particular, patients with t(4;14)-positive disease have worse prognosis compared to other MM subtypes. Herein, we demonstrated that t(4;14)-positive cells are highly dependent on the mevalonate (MVA) pathway for survival. Moreover, we showed that this metabolic vulnerability is immediately actionable, as inhibiting the MVA pathway with a statin preferentially induced apoptosis in t(4;14)-positive cells. In response to statin treatment, t(4;14)-positive cells activated the integrated stress response (ISR), which was augmented by co-treatment with bortezomib, a proteasome inhibitor. We identified that t(4;14)-positive cells depend on the MVA pathway for the synthesis of geranylgeranyl pyrophosphate (GGPP), as exogenous GGPP fully rescued statin-induced ISR activation and apoptosis. Inhibiting protein geranylgeranylation similarly induced the ISR in t(4;14)-positive cells, suggesting that this subtype of MM depends on GGPP, at least in part, for protein geranylgeranylation. Notably, fluvastatin treatment synergized with bortezomib to induce apoptosis in t(4;14)-positive cells and potentiated the anti-tumor activity of bortezomib in vivo. Our data implicate the t(4;14) translocation as a biomarker of statin sensitivity and warrant further clinical evaluation of a statin in combination with bortezomib for the treatment of t(4;14)-positive disease.