The Lipid Addiction of Diffuse Large B-Cell Lymphoma (DLBCL) and Potential Treatment Strategies with Novel Fatty Acid Synthase (FASN) Small Molecule Inhibitors

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 4490-4490 ◽  
Author(s):  
Ravi Dashnamoorthy ◽  
Nassera Abermil ◽  
Afshin Behesti ◽  
Paige Kozlowski ◽  
Frederick Lansigan ◽  
...  
Keyword(s):  
Cell Death ◽  
Fatty Acid ◽  
Lipid Metabolism ◽  
Cell Survival ◽  
Binding Affinity ◽  
Cell Lines ◽  
Small Molecule ◽  
Research Funding ◽  
Fatty Acid Synthase ◽  
The Impact

Abstract Background: Fatty acid (FA) metabolism is altered in several cancers through increased de novo synthesis of lipids via up-regulation fatty acid synthase (FASN) and increased utilization of lipids via β-oxidation. We investigated the dependence of DLBCL survival on FA metabolism. In addition, we examined novel FASN inhibitors TVB3567 and TVB3166 in comparison with cerulenin for the effects on cell survival and PI3K and MAPK-related biological pathways associated with tumor-related FA metabolism in DLBCL. Methods: FASN inhibitors, TVB3567 and TVB3166 (3V Biosciences, CA), cerulenin (FASN inhibitor), orlistat (anti-lipoprotein lipase (LPL) and FASN), PI3K/mTOR, and MEK small molecule inhibitors were studied in OCI-LY3, OCI-LY19, SUDHL4, SUDHL6, and SUDHL10 DLBCL cell lines for the effects of FA inhibition on lipid metabolism, cell signaling, and cell death. The effects of FASN inhibition on global gene expression profile (GEP) were also determined with Affymetrix Human 2.0 ST Genechip with Gene set enrichment analysis (GSEA). We also utilized short hairpin RNA interference (shRNA) to study interactions between FASN and PI3K/MAPK signaling. Finally, AutoDock Vina software (autodock.scripps.edu) was utilized to analyze drug target (FASN enzyme) binding affinity and assist in the design of FASN inhibitors with higher target binding affinity. Results: DLBCL cell lines OCI-LY3, SUDHL4, and SUDHL6 grown in the presence of lipoprotein-depleted serum showed exquisite sensitivity to lipid deprivation resulting in near complete cytotoxicity by MTT. Lipid deprivation-induced apoptotic cell death, detected as cleaved caspase 3 and PARP and Annexin-V/PI positivity, in these cells. Further, these effects were completely rescued by Very Low Density Lipoprotein (VLDL) supplementation to growth medium in SUDHL4 confirming the high lipid-dependency on cell survival in DLBCL. Treatment with pharmacological inhibitors of FASN (ie, TVB3567, TVB3166, cerulenin, or orlistat) resulted in a dose- and time-dependent reduction in cell viability in all DLBCL cell lines. Ingenuity Pathway Analysis (IPA) from GEP with cerulenin-treated OCI-LY3 showed prominent suppression of CD40, TNF, and NFκB dependent inflammatory responses as well as activation of apoptosis as predominant biological activities including significant down-regulation of genes involved in Krebs cycle and p38 MAPK pathways. Interestingly, upstream regulation by IPA predicted activation of MEK/ERK and MYC-dependent functions; and in OCI-LY3 with shRNA knock down of FASN, we observed constitutive activation of ERK as detected with increased phosphorylation by western blot. Activation of MEK/ERK and MYC is expected in part owing to metabolic stress induced by FASN inhibition. Considering the impact of MEK/ERK pathways on lipid metabolism, we next investigated the impact of MEK/ERK on FA metabolism. FASN was significantly decreased following MEK or ERK shRNA in OCILY-3 and SUDHL10 cells. Similarly, pharmacological inhibition of MEK or PI3K/mTOR (using novel small molecule agents AZD6244 (selumetinib) or BEZ235, respectively) resulted in marked down-regulation of FASN expression. Based on these results, FASN inhibition appears to a promising therapeutic target for the treatment of DLBCL, however attaining clinical efficacy with existing compounds require the effective drug concentration to be within the nanomolar range. Thus, we utilized AutoDock to determine drug docking enzyme inhibition constant (ki). We identified high ki values of 33μM and 180μM for Cerulenin and Orilstat, respectively. Therefore, we have developed/constructed modified novel and potent anti-FA compounds with ki <1μM that are currently being investigated. Conclusions: Collectively, we demonstrated that DLBCL cell survival is highly dependent on FA metabolism and that targeting lipid metabolism may be harnessed as a potential therapeutic strategy. We also showed that MEK/ERK-dependent mechanisms are intimately involved in promoting lipid addiction in DLBCL cells. Further investigation is warranted to delineate the mechanisms through which MEK/ERK regulate FASN expression and to determine in vivo implications of FASN inhibition on DLBCL tumor growth. In addition, continued development, design, and enhancement are needed to construct the most optimal anti-FA therapeutic agents. Disclosures Lansigan: Teva Pharmaceuticals: Research Funding; Spectrum Pharmaceuticals: Research Funding.

Mechanisms of Acquired Resistance to Venetoclax in Preclinical AML Models

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 328-328 ◽  
Author(s):  
Qi Zhang ◽  
Rongqing Pan ◽  
Lina Han ◽  
Ce Shi ◽  
Stephen E. Kurtz ◽  
...  
Keyword(s):  
Cell Death ◽  
Cell Lines ◽  
Small Molecule ◽  
Research Funding ◽  
Synergistic Effects ◽  
Acquired Resistance ◽  
Parental Cell ◽  
Resistant Cell ◽  
Flt3 Inhibitors ◽  
Resistant Cells

Abstract BH3-mimetic ABT-199 (venetoclax, VEN) is a selective small-molecule antagonist of the anti-apoptotic BCL-2 protein. It binds to BCL-2 specifically, causing the release of pro-apoptotic BAX and BH3-only proteins and induction of cell death. Our studies indicated that AML is a BCL-2 dependent disease that, in pre-clinical studies, responds robustly to VEN by induction of apoptotic cell death (Pan et al., Cancer Discovery 2014). As a single agent, VEN demonstrated clinical activity in relapsed/refractory AML, yet patients who initially responded ultimately developed resistance and progressed. In this study we investigated mechanisms of acquired resistance to VEN in preclinical AML models. First, we generated 5 VEN-resistant cell lines (OCI-AML2, Kasumi, KG-1, MV4;11 and Molm13; with VEN cell-killing IC50s of 0.021µM, 0.046µM, 0.073µM, 0.020µM and 0.050µM, respectively) by exposing the cells to gradually increasing VEN concentrations. The IC50s of resistant cells are 15.2µM, 5.7µM, 31.6µM, 11.4µM and 15.4µM (124-723-fold greater than their parental counterparts). Protein analysis of resistant cells using immunoblotting demonstrated increased expression of MCL-1, a known resistance factor to VEN, in 4 resistant cell lines (OCI-AML2, KG-1, Mv4;11 and Molm13); and BCL-XL increase in MV4;11 and Molm13 resistant cells. To characterize the functional role of MCL-1 and BCL-XL in resistance to VEN, we co-treated parental and resistant cells with novel MCL-1 and BCL-XL- selective inhibitors (A-1210477 and A-1155463). The combination of VEN with A-1210477 or A-1155463 showed synergistic growth inhibition in all 5 parental cell lines (combination indices (CI) for A-1210477 were 0.15-0.62; CI for A-1155463 were 0.33-0.51, except >3 for KG-1). Notably, 4 out of 5 resistant cell lines (OCI-AML2, Kasumi, MV4;11, Molm13) became more sensitive to MCL-1 selective inhibitor A-1155463 but not to BCL-XL inhibitor A-1210477. However, no further effects were seen in resistant cells when combined with VEN. We next compared sensitivity of three paired parental and resistant cell lines (OCI-AML2, MV4;11 and Molm13) to a library of 130 specific small-molecule inhibitors (Tyner, et.al.. Cancer Res. 2013). Cells were co-treated with VEN and each specific inhibitor, and drug target scores were calculated based on the IC50 of measured effectiveness of panel drugs against the cells. The screening revealed modulation of sensitivity to mTOR, MEK, and FLT3 pathways in resistant cells (Fig.1C). To confirm these findings, we next co-treated AML cells with VEN and specific inhibitors of the mTOR pathway (rapamycin and AZD2014) or MEK pathway (CI1040) in all 5 paired parental and resistant cell lines; or with FLT3 inhibitors (quizartinib and sorafenib) in parental and resistant MV4;11 and Molm13, which harbor FLT3-ITD. The combination of VEN and AZD2014 achieved synergistic effects in all 5 parental cell lines (CI AZD2014: 0.08-0.94), and VEN/rapamycin were synergistic in 3 parental cell lines (CI rapamycin: 0.00-0.55, except 1.76 for KG-1 and 1.59 for Molm13). Combination of VEN with CI1040 achieved synergy in OCI-AML2, Kasumi, MV4;11 and Molm13 parental cell lines (CI: 0.14-0.61). Finally, VEN/FLT3 inhibitors achieved synergistic effects in MV4;11 and Molm13 parental cell lines (CI quizartinib: 0.66-0.69; CI sorafenib: 0.64-0.71). The resistant cell lines exhibited sensitivity to these inhibitors as single agents, and no synergistic effects were seen when combined with VEN. We have further induced in vivo resistance in two primary AML xenografts by treating NSG mice engrafted with 2nd passage AML cells with 100 mg/kg Q.D. VEN for 4 weeks followed by harvest of leukemic cells that repopulated the mouse after treatment discontinuation. While the proteomics, gene expression (RNAseq) and drug screening assays are in progress, preliminary immunoblotting studies demonstrated decreased expression of BCL-XL and BCL-2 (Fig.1B). In summary, we identified multiple mechanisms of acquired resistance to VEN, which ultimately modulate the balance between pro- and anti-apoptotic BCL-2 family members. Our studies indicate that upfront combination of VEN with selective inhibitors of MCL-1, or with inhibitors of specific signaling pathways, can synergistically induce apoptosis in AML cells and conceivably prevent emergence of VEN resistance. Disclosures Leverson: AbbVie: Employment, Equity Ownership. Tyner:Aptose Biosciences: Research Funding; Constellation Pharmaceuticals: Research Funding; Janssen Pharmaceuticals: Research Funding; Array Biopharma: Research Funding; Incyte: Research Funding. Konopleva:Novartis: Research Funding; AbbVie: Research Funding; Stemline: Research Funding; Calithera: Research Funding; Threshold: Research Funding.

Small Molecule Inhibitors of HER2 Inhibit Proliferative Signaling and Promote Apoptosis in Ph+ ALL

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1397-1397
Author(s):  
Mary E Irwin ◽  
Laura Nelson ◽  
Janice M Santiago-O'Farrill ◽  
Claudia P Miller ◽  
Doris R. Siwak ◽  
...  
Keyword(s):  
Cell Death ◽  
Cell Lines ◽  
Small Molecule ◽  
Tyrosine Kinases ◽  
Research Funding ◽  
Receptor Tyrosine Kinases ◽  
Kinase Inhibitor ◽  
Her2 Receptor ◽  
Small Molecule Kinase Inhibitor ◽  
Her2 Signaling

Abstract Abstract 1397 The ERBB family of receptor tyrosine kinases (EGFR, Her-2, Her-3 and Her-4) are receptor tyrosine kinases that, through mutation or aberrant expression, serve as oncogenes by promoting hallmark behaviors of cancer in many solid tumors. Previous work has suggested that HER2 is expressed in as much as 30% of B-ALL patients, and correlates with chemoresistance. We therefore hypothesized that HER2 signaling in Ph+ ALL may augment growth signaling and promote other malignant behaviors, such as resistance to cell death and independence from growth factors. Western blot and flow cytometric analyses of two human Ph+ ALL cell lines, Z119 and Z181, revealed cell surface expression of HER2, but not other family members. To determine the role of HER2 signaling in Ph+ ALL cell lines, the pan-HER family small molecule kinase inhibitor canertinib was used, and reverse phase protein array (RPPA) was conducted in Z119 and Z181 cell lines. Briefly, lysates from canertinib treated cells were spotted using a GeneTAC™ G3 arrayer onto nitrocellulose-coated FAST® slides. Incubation of the slides was performed with forty-three antibodies directed towards various cell signaling proteins followed by colorimetric detection and results were subsequently validated by western blotting. RPPA analyses revealed that treatment with canertinib effectively diminished HER2 phosphorylation in both cell lines. Additionally, we found decreased phosphorylation of the pro-survival molecules ribosomal protein S6, p70S6kinase, and c-Src, as well as increased expression of the pro-apoptotic molecules BIM and cleaved-PARP in both Ph+ ALL cell lines. Congruent with these findings, elevated activity of the executioner caspase 3 and increased DNA fragmentation, two distinct biochemical markers of apoptosis, were present after canertinib treatment in Z181 and Z119 cells, suggesting that inhibition of HER2 signaling results in programmed cell death of Ph+ ALL cell lines. This induction of apoptosis paralleled a decrease in overall proliferation of these cell lines, further implicating HER2 signaling in proliferation of Ph+ ALL. Next, we analyzed if clinically approved inhibitors of HER2 function could be utilized to produce the same biological consequence as canertinib in Ph+ ALL cell lines. Lapatinib (Tykerb) is a dual EGFR/HER2 small molecule kinase inhibitor approved by the FDA for the treatment of breast cancer. Consistent with our results utilizing canertinib, lapatinib was capable of inhibiting proliferation of both Z119 and Z181 cell lines. Interestingly, the FDA approved monoclonal antibody HER2 inhibitor trastuzumab (Herceptin) did not inhibit proliferation of these cell lines. Similarly, trimerized herceptin conjugates, which improve internalization of HER2 receptor, also had no effect on Ph+ ALL cell line proliferation. These results highlight an important distinction between the effects of the intracellular small molecule inhibitors of HER2 and monoclonal HER2 antibodies. In particular, extracellular engagement of the HER2 receptor by monoclonal antibodies may not be effective in targeting the HER2 signaling pathways required for proliferation and survival of Ph+ ALL. Taken together, our studies suggest that HER2 may play an important role in growth and survival signaling of Ph+ ALL cell lines and inhibition of HER2 with small molecule kinase inhibitors may improve treatment regimens. Thus, additional studies are warranted to determine the importance of HER2 in clinical specimens and the potential benefit of combining HER2 inhibitor therapy with imatinib treatment for Ph+ ALL. Disclosures: Mills: Glaxosmithkline: Research Funding; Pfizer: Research Funding.

scholarly journals Targeting Fatty Acid Synthase Modulates Metabolic Pathways and Inhibits Cholangiocarcinoma Cell Progression

2021 ◽  
Vol 12 ◽  
Author(s):  
Jittima Tomacha ◽  
Hasaya Dokduang ◽  
Sureerat Padthaisong ◽  
Nisana Namwat ◽  
Poramate Klanrit ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Lipid Metabolism ◽  
Cell Lines ◽  
Fatty Acid Synthase ◽  
Adenosine Diphosphate ◽  
High Expression ◽  
Migration And Invasion ◽  
Cell Progression ◽  
Metabolomics Study ◽  
Coa Reductase

An aberrant regulation of lipid metabolism is involved in the pathogenesis and progression of cancer. Up-regulation of lipid biosynthesis enzymes, including acetyl-CoA carboxylase (ACC), fatty acid synthase (FASN) and HMG-CoA reductase (HMGCR), has been reported in many cancers. Therefore, elucidating lipid metabolism changes in cancer is essential for the development of novel therapeutic targets for various human cancers. The current study aimed to identify the abnormal expression of lipid-metabolizing enzymes in cholangiocarcinoma (CCA) and to evaluate whether they can be used as the targets for CCA treatment. Our study demonstrated that a high expression of FASN was significantly correlated with the advanced stage in CCA patients. In addition, survival analysis showed that high expression of FASN and HMGCR was correlated with shorter survival of CCA patients. Furthermore, FASN knockdown inhibited the growth, migration and invasion in CCA cell lines, KKU055 and KKU213, as well as induced cell cycle arrest and apoptosis in the CCA cell lines. In addition, metabolomics study further revealed that purine metabolism was the most relevant pathway involved in FASN knockdown. Adenosine diphosphate (ADP), glutamine and guanine levels significantly increased in KKU213 cells while guanine and xanthine levels remarkably increased in KKU055 cells showing a marked difference between the control and FASN knockdown groups. These findings provide new insights into the mechanisms associated with FASN knockdown in CCA cell lines and suggest that targeting FASN may serve as a novel CCA therapeutic strategy.

Cyclin D1 Over-Expressing Mantle Cell Lymphoma Cells Are Hypersensitive to Inhibition of Fatty Acid Synthase (FASN)

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1656-1656
Author(s):  
Michael A. Dengler ◽  
Matthias Gutekunst ◽  
Stephanie Kopacz ◽  
Heike Horn ◽  
Ute Hofmann ◽  
...  
Keyword(s):  
Cell Death ◽  
Fatty Acid ◽  
Cyclin D1 ◽  
Mantle Cell Lymphoma ◽  
Cell Lines ◽  
Fatty Acid Synthase ◽  
Cell Lymphoma ◽  
B Cell Lymphoma ◽  
Proapoptotic Protein ◽  
Mantle Cell

Abstract Abstract 1656 Mantle cell lymphoma (MCL) is an aggressive type of B-cell lymphoma characterized by a t(11;14)(q13;q32) chromosomal translocation resulting in a constitutive over-expression of cyclin D1. Cyclin D1 is a multifunctional protein not only regulating cell cycle progression but also affecting other cellular functions including glucose and lipid metabolism. In this study, we investigated the effects of the fatty acid synthase (FASN) inhibitors orlistat and C75 on viability of different MCL cell lines including JEKO-1, MINO, Granta-519, JVM-2, and Rec-1. In all cell lines inhibition of FASN alone induced apoptosis. In contrast, normal peripheral blood lymphocytes were resistant to these compounds. This proapoptotic effect was dependent on cyclin D1 as silencing of cyclin D1 partially rescued cells from induction of cell death following FASN inhibition. Inhibition of FASN led to a strong induction of the proapoptotic protein NOXA (PMAIP) in all MCL cell lines investigated independent of the p53 status. Pre-treatment of cells with NOXA siRNA significantly reduced induction of cell death demonstrating the predominant role of this proapoptotic protein for the observed effects. We then analyzed the combined effects of inhibition of FASN with a panel of compounds with potential clinical relevance. Combination of FASN inhibitors with the BH3 mimetic ABT737, the proteasome inhibitor Bortezomib, and the glycolysis inhibitor 2-deoxy-D-glucose (2-DG) led to an almost complete loss of viability. These combinatory effects were selective for MCL cells as the same treatments had almost no effects on cell viability of primary PBMCs or fibroblasts from healthy donors. Bortezomib, 2-DG, and ABT737 enhanced the proapoptotic effect of FASN inhibitors by further disturbing the balance of pro- and antiapoptotic Bcl-2 family proteins: FASN inhibitor mediated induction of NOXA was enhanced by Bortezomib whereas 2-DG significantly reduced the NOXA antagonist Mcl-1. In summary, our results suggest that FASN inhibitors exert significant antitumoral activity especially in combination with Bcl-2 family modulators in different MCL cell lines and may therefore represent an attractive model for the design of new therapeutic approaches for this entity. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Functional Characterization of Genes Driving Enhanced Biological Aggressiveness of Myeloma Cells: Identification of Novel and Understudied "Drivers" of Myeloma

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 313-313
Author(s):  
Huihui Tang ◽  
Ryosuke Shirasaki ◽  
Ricardo De Matos Simoes ◽  
Sara Gandolfi ◽  
Olga Dashevsky ◽  
...  
Keyword(s):  
Cell Growth ◽  
Cell Survival ◽  
Cell Lines ◽  
Transcriptional Activation ◽  
Research Funding ◽  
Oncology Research ◽  
Positive Regulators ◽  
Genome Scale ◽  
The Impact ◽  
Crispr Activation

Loss-of-function (LOF) studies (e.g. using RNAi or CRISPR) have historically been the main functional approaches to identify and study genes which drive the biology of Multiple Myeloma(MM) or other neoplasias. We hypothesized though that substantial complementary data can be derived from systematically examining the impact of transcriptional activation of endogenous genomic loci of different genes. To perform such gain-of-function (GOF) studies in an open-ended genome-scale manner, we applied CRISPR activation approaches in 4 MM lines (MM1S, KMS11, LP1, L363) which were transduced with the dCas9-P65-HSF transcriptional activation system and the Calabrese genome-scale sgRNA library (2 pooled sub-libraries; total of ~110,000 sgRNAs targeting promoters of ~18000 genes; initial coverage ~800-1000 cells/sgRNA). Next generation sequencing quantified the sgRNA abundance in MM cells at baseline and various time points (e.g. 2-12 weeks of culture), and rank aggregation algorithms identified genes with statistically significant enrichment or depletion of their sgRNAs, reflecting positive vs. negative, respectively, effects of GOF of these genes on MM cell survival/proliferation. These studies identified distinct groups of genes which serve as positive regulators of MM cell growth in at least 3 of the cell lines tested, including critical transcription factors (TFs)/cofactors, such as POU2F2, POU2AF1, IRF4, MYC; growth factor signaling mediators, such as IGF1R and IRS1; Ras family members (e.g. KRAS in MM1S cells); diverse members of the solute carrier family of transporters for amino acids and other bioactive small molecules. We also observed positive regulators of MM cell growth with distinct roles in certain cell lines, e.g. induction of IKZF3, IKZF1, RELA, CD48, MBNL1, PAX2 exhibited significantly more pronounced role as positive regulators of MM1S cells compared to the other cell lines tested. Notably, several positive regulators of MM growth identified in these CRISPR activation studies are not essential for MM cell survival/proliferation in CRISPR knockout studies in the same MM cell lines or many others. Examples of such genes include the TFs POU2F2 (Oct2) and PAX2, the TRAF interacting protein TIFA or the Toll-like receptor TLR4. We went on to validate these results for several such genes (e.g. POU2F2, POU2AF1) with individual sgRNAs for CRISPR activation and/or cDNA overexpression (vs. isogenic controls) in competition experiments and cell cycle analyses. We focused on further probing the mechanistic basis for the role of POU2AF1 as one of the top positive regulators of MM cell growth and performed RNA sequencing analyses of LP1 cells harboring induction of POU2AF1 expression using CRISPR activation. We observed upregulation of a distinct cluster of &gt;50 genes that are themselves positive regulators of LP1 cell growth in our genome-scale CRISPR activation studies. While some of these are known drivers of tumor cell growth (e.g. AURKB, E2F1, FGFR3), the large majority of these POU2AF1-driven positive regulators of MM cell growth have not been previously studied in MM; and exhibit a distinct enrichment for transcriptional regulators and other genes which are not required for LP1 cell survival/proliferation in CRISPR KO studies of LP1 cells. These results indicate that CRISPR-based activation of endogenous gene expression provides data which complementary to those derived from CRISPR LOF studies. Indeed, we not only validated through our GOF studies the relevance of genes which with prominent essentiality in CRISPR LOF studies (e.g. IRF4, POU2AF1, etc.), but also identified promising new candidate regulators of MM cell biology which are not essential for baseline survival/growth of MM cells, but can induce MM cell growth when further activated. These results provide novel insights into the biology of MM cells and may have therapeutic implications towards suppressing the ability of MM cells to transition to states of advanced biological aggressiveness. Disclosures Mitsiades: Takeda: Other: employment of a relative ; Ionis Pharmaceuticals: Honoraria; Fate Therapeutics: Honoraria; Arch Oncology: Research Funding; Sanofi: Research Funding; Karyopharm: Research Funding; Abbvie: Research Funding; TEVA: Research Funding; EMD Serono: Research Funding; Janssen/Johnson & Johnson: Research Funding.

Placental Accumulation of Triacylglycerols in Gestational Diabetes Mellitus and Its Association with Altered Fetal Growth are Related to the Differential Expressions of Proteins of Lipid Metabolism

2020 ◽  
Author(s):  
Manoharan Balachandiran ◽  
Zachariah Bobby ◽  
Gowri Dorairajan ◽  
Sajini Elizabeth Jacob ◽  
Victorraj Gladwin ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Fatty Acid ◽  
Lipid Metabolism ◽  
Gestational Diabetes ◽  
Gestational Diabetes Mellitus ◽  
Fetal Growth ◽  
Fatty Acid Synthase ◽  
Regulatory Element ◽  
Acid Oxidation ◽  
Placental Proteins

Abstract Introduction Gestational diabetes mellitus (GDM) exhibit altered placental lipid metabolism. The molecular basis of this altered metabolism is not clear. Altered placental expression of proteins of lipogenesis and fatty acid oxidation may be involved in the placental accumulation of triacylglycerols (TG). The present study was aimed at investigating the differential expressions of placental proteins related to lipid metabolism among GDM women in comparison with control pregnant women (CPW) and to correlate them with maternal and fetal lipid parameters as well as altered fetal growth. Materials and Methods Maternal blood, cord blood, and placental samples were collected from GDM and CPW. The biochemical parameters, glucose, lipid profile and free fatty acids (FFA) were measured. The placental TG content was measured. Differential placental expressions of proteins; phosphatidylinositol-3-kinase (PI3K) p85α, PI3K p110α,liver X receptor alpha (LXRα), sterol regulatory element binding protein1(SREBP1), fatty acid synthase (FAS), stearyl CoA desaturase1 (SCD1), lipoprotein lipase (LPL),Peroxisome proliferator-activated receptor (PPAR)α and PPARγ were analysed by western blotting and immunohistochemistry. Results Placental protein expressions of PI3K p110α, LXRα, FAS, SCD1, and LPL were found to be significantly higher, whereas PPARα and PPARγ were lower in GDM women compared with CPW. The placental TG content and cord plasma FFA were increased in GDM women compared with CPW. The placental TG content positively correlated with Ponderal index of GDM new-borns. Conclusion Differential expressions of placental proteins related to lipid metabolism in GDM might have led to placental TG accumulation. This might have contributed to the fetal overgrowth in GDM.

scholarly journals Stable Isotope Labeling Highlights Enhanced Fatty Acid and Lipid Metabolism in Human Acute Myeloid Leukemia

2018 ◽  
Vol 19 (11) ◽  
pp. 3325 ◽  
Author(s):  
Lucille Stuani ◽  
Fabien Riols ◽  
Pierre Millard ◽  
Marie Sabatier ◽  
Aurélie Batut ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Acute Myeloid Leukemia ◽  
Fatty Acid ◽  
Lipid Metabolism ◽  
Myeloid Leukemia ◽  
Metabolic Reprogramming ◽  
Frequent Relapses ◽  
The Impact ◽  
Mutant Cells ◽  
Acute Myeloid

Background: In Acute Myeloid Leukemia (AML), a complete response to chemotherapy is usually obtained after conventional chemotherapy but overall patient survival is poor due to highly frequent relapses. As opposed to chronic myeloid leukemia, B lymphoma or multiple myeloma, AML is one of the rare malignant hemopathies the therapy of which has not significantly improved during the past 30 years despite intense research efforts. One promising approach is to determine metabolic dependencies in AML cells. Moreover, two key metabolic enzymes, isocitrate dehydrogenases (IDH1/2), are mutated in more than 15% of AML patient, reinforcing the interest in studying metabolic reprogramming, in particular in this subgroup of patients. Methods: Using a multi-omics approach combining proteomics, lipidomics, and isotopic profiling of [U-13C] glucose and [U-13C] glutamine cultures with more classical biochemical analyses, we studied the impact of the IDH1 R132H mutation in AML cells on lipid biosynthesis. Results: Global proteomic and lipidomic approaches showed a dysregulation of lipid metabolism, especially an increase of phosphatidylinositol, sphingolipids (especially few species of ceramide, sphingosine, and sphinganine), free cholesterol and monounsaturated fatty acids in IDH1 mutant cells. Isotopic profiling of fatty acids revealed that higher lipid anabolism in IDH1 mutant cells corroborated with an increase in lipogenesis fluxes. Conclusions: This integrative approach was efficient to gain insight into metabolism and dynamics of lipid species in leukemic cells. Therefore, we have determined that lipid anabolism is strongly reprogrammed in IDH1 mutant AML cells with a crucial dysregulation of fatty acid metabolism and fluxes, both being mediated by 2-HG (2-Hydroxyglutarate) production.

scholarly journals DNA break clustering inside repair domains predicts cell death and mutation frequency in human fibroblasts and in Chinese hamster cells for a 103x range of linear energy transfers

2020 ◽  
Author(s):  
Eloise Pariset ◽  
Ianik Plante ◽  
Artem L. Ponomarev ◽  
Louise Viger ◽  
Trevor Evain ◽  
...  
Keyword(s):  
Experimental Data ◽  
Cell Death ◽  
Cell Survival ◽  
Cell Lines ◽  
Cosmic Radiation ◽  
Human Fibroblasts ◽  
Chinese Hamster ◽  
Double Strand Breaks ◽  
Cell Orientation ◽  
Strand Breaks

ABSTRACTCosmic radiation, composed of high charged and energy (HZE) particles, causes cell death and mutations that can subsequently lead to cancers. Radiation-mediated mutations are induced by inter- and intra-chromosomal rearrangements (translocations, deletions, inversions) that are triggered by misrepaired DNA breaks, especially double-strand breaks (DSBs). In this work, we introduce a new model to predict radiation-mediated induction of cell death and mutation in two different cell lines across a large range of linear energy transfer (LET) values, based on the assumption that DSBs cluster into repair domains, as previously suggested by our group. Specifically, we propose that the probabilities of cell survival and cell mutation can be determined from the number of DSBs and the number of pairwise DSB interactions forming radiation-induced foci. We computed the distribution and locations of DSBs with the new simulation code RITCARD (relativistic ion tracks, chromosome aberrations, repair, and damage) and combined them with experimental data from HF19 human fibroblasts and V79 Chinese hamster cells to derive the parameters of our model and expand its predictions to the relative biological effectiveness (RBE) for cell survival and mutation in both cell lines in response to 9 different irradiation particles and energies ranging from 10 to 1,600 MeV/n. Our model generates the correct bell shape of LET dependence for RBE, as well as similar RBE values as experimental data, notably including data that were not used to set the model parameters. Interestingly, our results also suggest that cell orientation (parallel or perpendicular) with respect to the HZE beam can modulate the RBE for both cell death and mutation frequency. Cell orientation effects, if confirmed experimentally, would be another strong piece of evidence for the existence of DNA repair domains and their critical role in interpreting cellular sensitivity to cosmic radiation and hadron therapy.AUTHOR SUMMARYOne of the main hazards of human spaceflight beyond low Earth orbit is space radiation exposure. Galactic cosmic rays (GCRs), in particular their high-charge and high-energy particle component, induce a unique spatial distribution of DNA double strand breaks in the nucleus along their traversal in the cell [1], which result in significantly higher cancer risk than X-rays [2]. To mitigate this hazard, there is a significant need to better understand and predict the effects of cosmic radiation exposure at the cellular level. We have computationally predicted two biological endpoints – cell survival and probability of mutations, critical for cancer induction mechanisms – for the full spectrum of cosmic radiation types and energies, by modeling the distribution of DNA damage locations within the cell nucleus. From experimental results of cell survival and mutation probability in two standard cell lines, we were able to derive the parameters of the model for multiple radiation qualities, both biological endpoints, and two irradiation orientations. The model was validated against biological data and showed high predictive capability on data not used for tuning the model. Overall, this work opens new perspectives to predict multiple responses to cosmic radiation, even with limited experimental data available.

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