Project description:The function of DFNA5 remained unknown for a long time, but previous functional studies by Op de Beeck et al. (2011) revealed that DFNA5 induces a growth defect in mutDFNA5- transfected HEK293T cells, as well as other cells, leading to PCD (Op de Beeck et al., 2011). The cell death-inducing capacity of DFNA5 was not only restricted to human cell lines, but was also observed in the yeast model Saccharomyces cerevisiae (Van Rossom et al., 2012). This inspired us to perform a transcriptomic analysis using two different model organisms (mammalian, HEK293T, and yeast, S.cerevisiae) to further elucidate the mechanisms related to DFNA5. Comparison of 2 transfected yeast cell populations in 2 different growth phases. In total, 4 comparisons were made, each comparison was done in duplo by a colourflip. Every conditions is represented through 2 biol reps.
Project description:The function of DFNA5 remained unknown for a long time, but previous functional studies by Op de Beeck et al. (2011) revealed that DFNA5 induces a growth defect in mutDFNA5- transfected HEK293T cells, as well as other cells, leading to PCD (Op de Beeck et al., 2011). The cell death-inducing capacity of DFNA5 was not only restricted to human cell lines, but was also observed in the yeast model Saccharomyces cerevisiae (Van Rossom et al., 2012). This inspired us to perform a transcriptomic analysis using two different model organisms (mammalian, HEK293T, and yeast, S.cerevisiae) to further elucidate the mechanisms related to DFNA5. Comparison of two HEK293T transfected cell populations, either with a WT or mutated DFNA5 gene. There are 5 biol reps for the WT transfected cells and 6 biol reps for the mut DFNA5 transfected cells.
Project description:Cell death exists in many different forms. Some are accidental, but most of them have some kind of regulation and are called programmed cell death. Programmed cell death (PCD) is a very diverse and complex mechanism and must be tightly regulated. This study investigated PCD induced by DFNA5, a gene responsible for autosomal dominant hearing loss (HL) and a tumor suppressor gene (TSG) involved in frequent forms of cancer. Mutations in DFNA5 lead to exon 8 skipping and result in HL in several families. Expression of mutant DFNA5, a cDNA construct where exon 8 is deleted, was linked to PCD both in human cell lines and in Saccharomyces cerevisiae. To further investigate the cell death mechanism induced by mutant DFNA5, we performed a microarray study in both models. We used wild-type DFNA5, which does not induce cell death, as a reference. Our data showed that the yeast pathways related to mitochondrial ATP-coupled electron transport chain, oxidative phosphorylation and energy metabolism were up-regulated, while in human cell lines, MAP kinase-related activity was up-regulated. Inhibition of this pathway was able to partially attenuate the resulting cell death induced by mutant DFNA5 in human cell lines. In yeast, the association with mitochondria was demonstrated by up-regulation of several cytochrome c oxidase (COX) genes involved in the cellular oxidative stress production. Both models show a down-regulation of protein sorting- and folding-related mechanisms suggesting an additional role for the endoplasmic reticulum (ER). The exact relationship between ER and mitochondria in DFNA5-induced cell death remains unknown at this moment, but these results suggest a potential link between the two.
Project description:The function of DFNA5 remained unknown for a long time, but previous functional studies by Op de Beeck et al. (2011) revealed that DFNA5 induces a growth defect in mutDFNA5- transfected HEK293T cells, as well as other cells, leading to PCD (Op de Beeck et al., 2011). The cell death-inducing capacity of DFNA5 was not only restricted to human cell lines, but was also observed in the yeast model Saccharomyces cerevisiae (Van Rossom et al., 2012). This inspired us to perform a transcriptomic analysis using two different model organisms (mammalian, HEK293T, and yeast, S.cerevisiae) to further elucidate the mechanisms related to DFNA5.
Project description:The function of DFNA5 remained unknown for a long time, but previous functional studies by Op de Beeck et al. (2011) revealed that DFNA5 induces a growth defect in mutDFNA5- transfected HEK293T cells, as well as other cells, leading to PCD (Op de Beeck et al., 2011). The cell death-inducing capacity of DFNA5 was not only restricted to human cell lines, but was also observed in the yeast model Saccharomyces cerevisiae (Van Rossom et al., 2012). This inspired us to perform a transcriptomic analysis using two different model organisms (mammalian, HEK293T, and yeast, S.cerevisiae) to further elucidate the mechanisms related to DFNA5.
Project description:Plant secondary metabolites possess chemopreventive and antineoplastic properties, but the lack of information about their exact mechanism of action in mammalian cells hinders the translation of these compounds in suitable therapies. In light of this, firstly, Origanum vulgare L. hydroalcoholic extract was chemically characterized by spectrophotometric and chromatographic analyses; then, the molecular bases underlying its antitumor activity on B16-F10 and A375 melanoma cells were investigated. Oregano extract induced oxidative stress and inhibited melanogenesis and tumor cell proliferation, triggering programmed cell death pathways (both apoptosis and necroptosis) through mitochondria and DNA damage. By contrast, oregano extract was safe on healthy tissues, revealing no cytotoxicity and mutagenicity on C2C12 myoblasts, considered as non-tumor proliferating cell model system, and on Salmonella strains, by the Ames test. All these data provide scientific evidence about the potential application of this food plant as an anticancer agent in in vivo studies and clinical trials.
Project description:BACKGROUND:Although many studies suggested that aluminum (Al) induced programmed cell death (PCD) in plants, the mechanism of Al-induced PCD and its effects in Al tolerance is limited. This study was to investigate the mechanism and type of Al induced PCD and the relationship between PCD and Al tolerance. RESULTS:In this study, two genotypes of peanut 99-1507 (Al tolerant) and ZH2 (Al sensitive) were used to investigate Al-induced PCD. Peanut root growth inhibition induced by AlCl3 was concentration and time-dependent in two peanut varieties. AlCl3 at 100 ?M could induce rapidly peanut root tip PCD involved in DNA cleavage, typical apoptotic chromatin condensation staining with DAPI, apoptosis related gene Hrs203j expression and cytochrome C (Cyt c) release from mitochondria to cytosol. Caspase3-like protease was activated by Al; it was higher in ZH2 than in 99-1507. Al increased the opening of mitochondrial permeability transition pore (MPTP), decreased inner membrane potential (??m) of mitochondria. Compared with the control, Al stress increased O2•- and H2O2 production in mitochondria. Reactive oxygen species (ROS) burst was produced at Al treatment for 4 h. CONCLUSIONS:Al-induced PCD is earlier and faster in Al-sensitive peanut cultivar than in Al-tolerant cultivar. There is a negative relationship between PCD and Al resistance. Mitochondria- dependence PCD was induced by Al and ROS was involved in this process. The mechanism can be explained by the model of acceleration of senescence under Al stress.
Project description:Hepatocellular carcinoma (HCC) is the fourth largest cause of cancer-related deaths worldwide with limited therapeutic interventions. Renewed interest in natural products as drug leads has resulted in a paradigm shift toward the rapid screening of medicinal plants for the discovery of new chemical entities. Rotundic acid (RA), a plant-derived triterpenoid, has been anecdotally reported to possess anti-inflammatory and cardio-protective abilities. The present study highlights the anti-cancer efficacy of RA on HCC in vitro and in vivo. The inhibitory effects of RA on HCC cell viability was determined by MTT. Soft agar colony formation and clonogenic assays also showed that RA inhibited HCC cell proliferation. Flow cytometry, confocal, and western blot results further indicated that RA induced cell cycle arrest, DNA damage, and apoptosis by modulating the AKT/mTOR and MAPK pathways. Besides the suppression of migration and invasion, tube formation and VEGF-ELISA revealed the anti-angiogenic abilities of RA on HCC. Moreover, RA also inhibited tumor growth in a HepG2 xenograft mouse model. To our best knowledge, this is the first extensive study of the anticancer activity of RA on HCC. The results demonstrate that RA could be a potential drug candidate for HCC treatment.