we used the yeast Saccharomyces cerevisiae as a model organism for studying deregulate glycolytic flow that was induced by the insertion of the gene encoding cancer specific shorter form of 6-phosphofructo-1-kinase (Pfk). However, in a specific ecological niche growth condition were determined that allowed faster growth of the transformant with the modified, cancer characteristic Pfk enzyme in respect to the transformant with the native human Pfk enzyme. S. cerevisiae transformant encoding the highly active shorter Pfk fragments can be used as a model organism for studying deviant energetic metabolism in cancer cells (Warburg effect).
F.09 Development of a new technological process or technology
COBISS.SI-ID: 37878533Metformin is the most widely prescribed oral anti-diabetic drug. Some studies suggest that it has protective role against some types of cancer, including the breast cancer. Here, we explored whether high glucose concentration can mask the effect of physiological concentrations of metformin on MDA-MB-231 breast cancer cells. Proliferating MDA-MB-231 breast cancer cells were grown in the presence of normal (1 g/L) or high (4.5 g/L) glucose concentration. As assessed by Hoechst assay, proliferation rate remained similar between normal and high glucose conditions, suggesting that glucose is not a limiting factor for the MDA-MB-231 cell growth under standard cell culture conditions. Low metformin concentrations failed to inhibit MDA-MB-231 cell proliferation under normal or high glucose conditions, while proliferation was markedly suppressed in the absence of glucose in cell culture medium. To mimic low glucose availability, we used low, physiological concentration of 2-deoxy glucose, which sensitized cancer cells to metformin’s action under normal (1 g/l) glucose condition. Our results show that glucose availability determines anti-proliferative action of low metformin concentrations on MDA-MB-231 breast cancer cells. Metformin had more significant effect on mitochondrial membrane potential under zero glucose availability. One of the reasons could be that cancer cells under glucose deficient condition are highly dependent on carbon sources that are metabolized in mitochondria, for growth and proliferation. We demonstrate that media composition can have a major impact on low metformin concentrations action and needs to be considered to avoid erroneous data interpretation.
F.02 Acquisition of new scientific knowledge
COBISS.SI-ID: 11194964Cell counting is an important method for evaluation of several phenomena in biology and medicine, however, it is time consuming, prone to user bias and often considered tiresome. To speed up the counting process and two automatic and semi-automatic cell counting programs were written in collaboration with two groups from the Faculty of Computer and Information Sciences (UNI LJ): CellCounter and Learn123. While CellCounter is based on predefined and fine-tuned sequence of filters optimized on sets of chosen experiments, Learn123 uses an evolutionary algorithm to determine the adapt filter parameters based on a learning set of images. CellCounter also includes an extension for analysis of overlaying images. The programs enable consistent, robust, fast and accurate detection of fluorescent objects and can therefore be applied to a range of different applications in different fields of life sciences where fluorescent labelling is used for quantification of various phenomena. Both programs are frequently used in our group and have significantly quickened the counting process. Both programs are also available online for free, update for Learn123 is in preparation. Both programs were presented on international conferences (COBISS ID: 10605908 and 1536324291). IF=2.331 Journal of Microscopy
F.01 Acquisition of new practical knowledge, information and skills
COBISS.SI-ID: 11059028