13 research outputs found
Prijenosnici natrija i glukoze: nove mete ciljanih terapija u lijeÄenju raka?
Glucose, the key source of metabolic energy, is imported into cells by two categories of transporters: 1) facilitative glucose transporters (GLUTs) and 2) secondary active sodium-glucose cotransporters (SGLTs). Cancer cells have an increased demand for glucose uptake and utilisation compared to normal cells. Previous studies have demonstrated the overexpression of GLUTs, mainly GLUT1, in many cancer types. As the current standard positron emission tomography (PET) tracer 2-deoxy-2-(18F)fluoro-D-glucose (2-FDG) for imaging tumour cells via GLUT1 lacks in sensitivity and specificity, it may soon be replaced by the newly designed, highly sensitive and specific SGLT tracer Ī±-methyl-4-(F-18)fluoro-4-deoxy-Dglucopyranoside (Me-4FDG) in clinical detection and tumour staging. This tracer has recently demonstrated the functional activity of SGLT in pancreatic, prostate, and brain cancers. The mRNA and protein expression of SGLTs have also been reported in colon/colorectal, lung, ovarian, head, neck, and oral squamous carcinomas. So far, SGLTs have been poorly investigated in cancer, and their protein expression and localisation are often controversial due to a lack of specific SGLT antibodies. In this review, we describe current knowledge concerning SGLT1 and SGLT2 (over)expression in various cancer types. The findings of SGLTs in malignant cells may help in developing novel cancer therapies with SGLT2 or SGLT1/SGLT2 inhibitors already used in diabetes mellitus treatment.Glukoza, glavni izvor metaboliÄke energije, ulazi u stanicu na dva naÄina: 1) olakÅ”anom difuzijom pomoÄu prijenosnika glukoze GLUT i 2) sekundarno aktivnim prijenosom pomoÄu prijenosnika natrija i glukoze SGLT. Stanice raka imaju poveÄani unos glukoze u usporedbi s normalnim stanicama. Prethodna istraživanja pokazala su poveÄanu ekspresiju prijenosnika GLUT, uglavnom GLUT1, u mnogim tipovima raka. Radiofarmaceutik (engl. tracer) 2-deoksi-2-(18F) fluoro-D-glukoza (2-FDG), koji se koristi za detekciju tumorskih stanica putem GLUT1, nije dovoljno osjetljiv i specifiÄan. Uskoro bi mogao biti zamijenjen Ī±-metil-4-(F-18) fluoro-4-deoksi-D-glukopiranozidom (Me-4FDG), novim i visoko osjetljivim, i specifiÄnim SGLT-radiofarmaceutikom u kliniÄkoj detekciji i odreÄivanju stadija tumora. Tim je radiofarmaceutikom nedavno dokazana funkcionalna aktivnost prijenosnika SGLT u raku guÅ”teraÄe, prostate i mozga. Ekspresija mRNA i proteina SGLT takoÄer je pronaÄena u raku debelog crijeva, pluÄa, jajnika, glave, vrata i ploÄastih stanica usne Å”upljine. Prijenosnici SGLT nedovoljno su istraženi u raku, a njihova ekspresija i lokalizacija Äesto su opreÄne zbog nedostatka specifiÄnih SGLT-protutijela. U ovom preglednom radu opisujemo trenutaÄna znanja o poveÄanoj ekspresiji prijenosnika SGLT1 i SGLT2 u razliÄitim tipovima raka. Spoznaje o ekspresiji i/ili lokalizaciji prijenosnika SGLT u malignim stanicama pomoÄi Äe u razvoju novih terapija u lijeÄenju raka koriÅ”tenjem veÄ poznatih antidijabetika, SGLT2 ili SGLT1/SGLT2 inhibitora
Notch pathway connections in primary leukaemia samples of limited size
Background: The Notch pathway combined with other signalling molecules acts specifically for the development of each blood cell type and differentiation stage. A causative role of Notch dysfunction in leukaemia development has been found in many studies so, initially only for T- acute lymphoblastic leukaemia (T-ALL) but more recently also for B cell and myeloid leukaemia. The aim of our study is to introduce a method for multiple direct analysis of the Notch pathway partners in a population of only 500 or fewer cells. The notion of this method consists in gaining insight into gene expression at the level of the malignant clone population. A small number of cells is a significant limitation when working on primary cells either when freshly isolated or when analysed after several days in cocultures. Methods: The primers were designed to avoid genomic amplification through the selection of 3ā² and 5ā² primers that hybridise with different exons. Cell lines and primary cells were collected and multiplex quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) performed on a descending number of cells, ranging from 2, 500 cells up to 50 cells per sample, for the Notch pathway genes and other transcription factors important for cell differentiation. ImageJ program, STATISTICA 13.1 software package and Studentās t-test were used for statistical evaluation. We checked protein expression by western blot. Results: We characterised the gene expression levels of Notch, Ikaros and Parp genes in leukaemia cell lines of B and T origin and in primary leukaemia samples of limited size. We further compared our results to the cDNA analysis obtained by total RNA isolation from a large number of cells as routinely performed in clinical laboratories, and finally tested the method described on primary cells from leukaemia patients. Conclusions: This rapid multiple gene expression analysis of a small population of cells provides efficient cell classification determining malignant changes as an important additional information for clinical leukaemia diagnostics as well as for in vitro studies of primary cells
Regulation of urokinase plasminogen activator system in tumor cells
Sustav urokinaznoga plazminogenskoga aktivatora (uPA) regulira razgradnju izvanstaniÄnog matriksa aktivacijom sveprisutne proteaze plazmina. Sudjeluje u nizu fizioloÅ”kih i patoloÅ”kih procesa te staniÄno je specifiÄno reguliran u organizmu na razini ekspresije proenzima, inhibitora i receptora. U ovom je radu opisana regulacija sustava uPA kod stanica glioblastoma A1235, manjkavih u popravku alkilirajuÄeg oÅ”teÄenja, nakon obrade inhibitorom poli(ADP-ribozil) polimeraze-1 (PARP-1) i alkilirajuÄim agensom N-metil-N'-nitro-N-nitrozoguanidinom (MNNG). MNNG je poveÄao uPA aktivnost u uskom rasponu koncentracija, u uvjetima visoke vijabilnosti, ali i zaustavljenog staniÄnog ciklusa. U tim je uvjetima inhibicija PARP-1 modulirala indukciju uPA aktivnosti inhibicijom popravka oÅ”teÄenja DNA. Aktivacija uPA bila je posljedica promjene u odnosu ekspresije uPA i njegovog inhibitora PAI-1 u Äemu je sudjelovao niz signalnih puteva. U drugom dijelu istraživanja naÅ”li smo da je derivat aspirina, natrijev salicilat (NaS) kod stanica tumora dojke MDA MB-231 promijenio ekspresiju uPA i PAI-1 i na taj naÄin smanjio uPA aktivnost u ovisnosti o koncentraciji i vremenu tretmana. NaS je takoÄer smanjio ekspresiju integrinskih podjedinica Ī±V i Ī²5, zaustavio staniÄni rast i inducirao morfoloÅ”ke promjene. Ovi rezultati svjedoÄe o složenoj regulaciji sustava uPA koja je staniÄno specifiÄna i ukljuÄuje niz signalnih puteva.Urokinase plasminogen activator (uPA) system regulates extracellular matrix remodeling by activating ubiquitous protease plasmin. The system is involved in various physiological and pathological processes and its regulation is cell specific involving the regulation of proenzyme, its inhibitors and receptor. This thesis describes the regulation of uPA system in A1235 glioblastoma cells, deficient in alkylation damage repair, after the treatment with poly(ADP-ribose) polymerase-1 (PARP-1) inhibitor and alkylating agent N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). MNNG has induced an increase in uPA activity in the narrow range of concentrations, under the conditions of high viability and the cell cycle arrest. In these experimental conditions, inhibition of PARP-1 has modulated induced uPA activity influencing the process of DNA repair. Increase in uPA activity was a consequence of change in the balance between uPA and its inhibitor PAI-1 expression and involved various signaling pathways. In the second part of this research, we found that sodium salicylate (NaS), a derivative of aspirin, has changed the expression of uPA and PAI-1 in MDA MB-231 breast cancer cells and inhibited uPA activity in a dose- and time-dependent manner. NaS has also inhibited the expression of Ī±V i Ī²5 integrin subunits, arrested cell growth and induced morphological changes. These results altogether confirmed the complex nature of uPA system regulation which is cell specific and involves various signaling pathways
Regulation of urokinase plasminogen activator system in tumor cells
Sustav urokinaznoga plazminogenskoga aktivatora (uPA) regulira razgradnju izvanstaniÄnog matriksa aktivacijom sveprisutne proteaze plazmina. Sudjeluje u nizu fizioloÅ”kih i patoloÅ”kih procesa te staniÄno je specifiÄno reguliran u organizmu na razini ekspresije proenzima, inhibitora i receptora. U ovom je radu opisana regulacija sustava uPA kod stanica glioblastoma A1235, manjkavih u popravku alkilirajuÄeg oÅ”teÄenja, nakon obrade inhibitorom poli(ADP-ribozil) polimeraze-1 (PARP-1) i alkilirajuÄim agensom N-metil-N'-nitro-N-nitrozoguanidinom (MNNG). MNNG je poveÄao uPA aktivnost u uskom rasponu koncentracija, u uvjetima visoke vijabilnosti, ali i zaustavljenog staniÄnog ciklusa. U tim je uvjetima inhibicija PARP-1 modulirala indukciju uPA aktivnosti inhibicijom popravka oÅ”teÄenja DNA. Aktivacija uPA bila je posljedica promjene u odnosu ekspresije uPA i njegovog inhibitora PAI-1 u Äemu je sudjelovao niz signalnih puteva. U drugom dijelu istraživanja naÅ”li smo da je derivat aspirina, natrijev salicilat (NaS) kod stanica tumora dojke MDA MB-231 promijenio ekspresiju uPA i PAI-1 i na taj naÄin smanjio uPA aktivnost u ovisnosti o koncentraciji i vremenu tretmana. NaS je takoÄer smanjio ekspresiju integrinskih podjedinica Ī±V i Ī²5, zaustavio staniÄni rast i inducirao morfoloÅ”ke promjene. Ovi rezultati svjedoÄe o složenoj regulaciji sustava uPA koja je staniÄno specifiÄna i ukljuÄuje niz signalnih puteva.Urokinase plasminogen activator (uPA) system regulates extracellular matrix remodeling by activating ubiquitous protease plasmin. The system is involved in various physiological and pathological processes and its regulation is cell specific involving the regulation of proenzyme, its inhibitors and receptor. This thesis describes the regulation of uPA system in A1235 glioblastoma cells, deficient in alkylation damage repair, after the treatment with poly(ADP-ribose) polymerase-1 (PARP-1) inhibitor and alkylating agent N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). MNNG has induced an increase in uPA activity in the narrow range of concentrations, under the conditions of high viability and the cell cycle arrest. In these experimental conditions, inhibition of PARP-1 has modulated induced uPA activity influencing the process of DNA repair. Increase in uPA activity was a consequence of change in the balance between uPA and its inhibitor PAI-1 expression and involved various signaling pathways. In the second part of this research, we found that sodium salicylate (NaS), a derivative of aspirin, has changed the expression of uPA and PAI-1 in MDA MB-231 breast cancer cells and inhibited uPA activity in a dose- and time-dependent manner. NaS has also inhibited the expression of Ī±V i Ī²5 integrin subunits, arrested cell growth and induced morphological changes. These results altogether confirmed the complex nature of uPA system regulation which is cell specific and involves various signaling pathways
Endometrial Glucose Transporters in Health and Disease
Pregnancy loss is a frequent occurrence during the peri-implantation period, when there is high glucose demand for embryonic development and endometrial decidualization. Glucose is among the most essential uterine fluid components required for those processes. Numerous studies associate abnormal glucose metabolism in the endometrium with a higher risk of adverse pregnancy outcomes. The endometrium is incapable of synthesizing glucose, which thus must be delivered into the uterine lumen by glucose transporters (GLUTs) and/or the sodium-dependent glucose transporter 1 (SGLT1). Among the 26 glucose transporters (14 GLUTs and 12 SGLTs) described, 10 (9 GLUTs and SGLT1) are expressed in rodents and 8 (7 GLUTs and SGLT1) in the human uterus. This review summarizes present knowledge on the most studied glucose transporters in the uterine endometrium (GLUT1, GLUT3, GLUT4, and GLUT8), whose data regarding function and regulation are still lacking. We present the recently discovered SGLT1 in the mouse and human endometrium, responsible for controlling glycogen accumulation essential for embryo implantation. Moreover, we describe the epigenetic regulation of endometrial GLUTs, as well as signaling pathways included in uterine GLUT's expression. Further investigation of the GLUTs function in different endometrial cells is of high importance, as numerous glucose transporters are associated with infertility, polycystic ovary syndrome, and gestational diabetes
PBDEs Found in House Dust Impact Human Lung Epithelial Cell Homeostasis
The toxicity of eight polybrominated diphenyl ethers (PBDEs) congeners detected in environmental and biological samples (BDE-28, -47, -99, -100, -153, -154, -183, and -209) was evaluated on the epithelial lung cells. Exposure to these PBDEs increased membrane disruption and a release of lactate dehydrogenase, accompanied by oxidative stress in cells through the formation of reactive oxygen species (ROS) and a decrease in mitochondrial membrane potential. Interestingly, some of the tested PBDEs increased apoptotic markers as well. For several congeners, the observed toxicity was time dependent, meaning that even smaller concentrations of these compounds will have negative effects over time. Such time-dependent toxicity was also confirmed for cell treatment with a real house dust sample extract. This could be indicative with regard to the constant exposure to a mixture of PBDE congeners through different pathways in the organism and thereby presenting a risk for human health. As such, our findings point to the importance of further studies on the negative effects of PBDEs to understand their mechanism of action in detail
<em>Globularia alypum</em> L. and Related Species: LC-MS Profiles and Antidiabetic, Antioxidant, Anti-Inflammatory, Antibacterial and Anticancer Potential
Species from the genus Globularia L. have been used as healing agents for various ailments, with utilization of Globularia alypum L. being most frequently reported. The aim of this study was to evaluate the antidiabetic, antioxidant, anti-inflammatory, antibacterial and anticancer potential of G. alypum and three related species, G. punctata Lapeyr., G. cordifolia L. and G. meridionalis (Podp.) O.Schwarz, in relation to their phytochemical compositions. Globularin and verbascoside were identified using LC-PDA-ESI-MSn as the major metabolites of G. alypum with known biological activities. G. alypum demonstrated the greatest Ī±-glucosidase inhibitory activity and DPPH radical scavenging activity (IC50 = 17.25 Ī¼g/mL), while its anti-inflammatory activity was not significantly different from those of related species. All investigated species showed considerable antibacterial activity against methicillin-resistant Staphylococcus aureus in the broth microdilution method (MIC = 1.42ā3.79 mg/mL). G. punctata also showed antibacterial activities against Escherichia coli (MIC = 1.42 mg/mL), Bacillus subtilis (MIC = 1.89 mg/mL), B. cereus (MIC = 2.84 mg/mL) and Enterococcus faecalis (MBC = 5.68 mg/mL). G. punctata, G. cordifolia and G. meridionalis showed greater anticancer potential than G. alypum. Obtained results indicate investigated Globularia species could serve as sources of diverse bioactive molecules, with G. punctata having the greatest antibacterial potential