Gurke R

References (2)

Title : Tumor microenvironment-derived monoacylglycerol lipase provokes tumor-specific immune responses and lipid profiles - Gruden_2023_Prostaglandins.Leukot.Essent.Fatty.Acids_196_102585
Author(s) : Gruden E , Kienzl M , Hasenoehrl C , Sarsembayeva A , Ristic D , Schmid ST , Maitz K , Taschler U , Hahnefeld L , Gurke R , Thomas D , Kargl J , Schicho R
Ref : Prostaglandins Leukot Essent Fatty Acids , 196 :102585 , 2023
Abstract : We recently described that monoacylglycerol lipase (MGL) is present in the tumor microenvironment (TME), increasing tumor growth. In this study we compare the implications of MGL deficiency in the TME in different tumor types. We show that subcutaneous injection of KP (Kras(LSL-G12D)/p53(fl/fl), mouse lung adenocarcinoma) or B16-F10 cells (mouse melanoma) induced tumor growth in MGL wild type (WT) and knockout (KO) mice. MGL deficiency in the TME attenuated the growth of KP cell tumors whereas tumors from B16-F10 cells increased in size. Opposite immune cell profiles were detected between the two tumor types in MGL KO mice. In line with their anti-tumorigenic function, the number of CD8(+) effector T cells and eosinophils increased in KP cell tumors of MGL KO vs. WT mice whereas their presence was reduced in B16-F10 cell tumors of MGL KO mice. Differences were seen in lipid profiles between the investigated tumor types. 2-arachidonoylglycerol (2-AG) content significantly increased in KP, but not B16-F10 cell tumors of MGL KO vs. WT mice while other endocannabinoid-related lipids remained unchanged. However, profiles of phospho- and lysophospholipids, sphingomyelins and fatty acids in KP cell tumors were clearly distinct to those measured in B16-F10 cell tumors. Our data indicate that TME-localized MGL impacts tumor growth, as well as levels of 2-AG and other lipids in a tumor specific manner.
ESTHER : Gruden_2023_Prostaglandins.Leukot.Essent.Fatty.Acids_196_102585
PubMedSearch : Gruden_2023_Prostaglandins.Leukot.Essent.Fatty.Acids_196_102585
PubMedID: 37573716

Title : Endocannabinoids as potential biomarkers: It's all about pre-analytics - Kratz_2021_J.Mass.Spectrom.Adv.Clin.Lab_22_56
Author(s) : Kratz D , Thomas D , Gurke R
Ref : J Mass Spectrom Adv Clin Lab , 22 :56 , 2021
Abstract : INTRODUCTION: Arachidonoyl ethanolamide (AEA) and 2-arachidonoyl glycerol (2-AG) are central lipid mediators of the endocannabinoid system. They are highly relevant due to their involvement in a wide variety of inflammatory, metabolic or malign diseases. Further elucidation of their modes of action and use as biomarkers in an easily accessible matrix, like blood, is restricted by their susceptibility to deviations during blood sampling and physiological co-dependences, which results in high variability of reported concentrations in low ng/mL ranges. OBJECTIVES: The objective of this review is the identification of critical parameters during the pre-analytical phase and proposal of minimum requirements for reliable determination of endocannabinoids (ECs) in blood samples. METHODS: Reported physiological processes influencing the EC concentrations were put into context with published pre-analytical research and stability data from bioanalytical method validation. RESULTS: The cause for variability in EC concentrations is versatile. In part, they are caused by inter-individual factors like sex, metabolic status and/or diurnal changes. Nevertheless, enzymatic activity in freshly drawn blood samples is the main reason for changing concentrations of AEA and 2-AG, besides additional non-enzymatic isomerization of the latter. CONCLUSION: Blood samples for EC analyses require immediate processing at low temperatures (>0 degreesC) to maintain sample integrity. Standardization of the respective blood tube or anti-coagulant, sampling time point, applied centrifugal force and complete processing time can further decrease variability caused by sample handling. Nevertheless, extensive characterization of study participants is needed to reduce distortion of clinical data caused by co-variables and facilitate research on the endocannabinoid system.
ESTHER : Kratz_2021_J.Mass.Spectrom.Adv.Clin.Lab_22_56
PubMedSearch : Kratz_2021_J.Mass.Spectrom.Adv.Clin.Lab_22_56
PubMedID: 34939056