A young researcher’s guide to NME/Nm23/NDP Kinase

Nucleoside diphosphate kinases (NDPKs) catalyze the exchange of the terminal phosphate from trinucleotides to dinucleotides through a high-energy phosphohistidine intermedier. They are encoded by NME genes and have been found, with a few exceptions, in all living beings. Besides their well-known function as key regulators of the cellular nucleotide homeostasis, they have been appointed numerous additional biochemical and biological functions. The discovery of NME1/NDPK A as the first metastasis suppressor opened new avenues in cancer research. Although the precise role of NME genes/proteins in cancer dissemination is not yet revealed, it seems that further intensive research in this field may lead to new advances in cancer diagnosis and prognosis, as well as encourage new therapeutic strategies.</p

Metastasis – recent scientific insights and challenging new therapeutic approaches

Majority of cancer patients never die from the original disease – primary tumor – but from the metastasis that disseminate throughout the body. Although they disseminate in millions only few of them succeeded in their journey and achieve their main goal – form a distant metastatic colony which is able to thrive in an inhospitable environment of an unrelated tissue. This review will summarize in brief some of the recent advances in cancer invasion and metastasis investigations and possibilities in using these findings for the benefit of cancer patients

Head and Neck Tumor Cells Exhibit Altered Proliferation upon Overexpression of nm23 Genes

nm23 was identified as a metastasis suppressor gene but is also appointed to a number of other biological functions. The goal of this study was to reveal the influence of ectopic expression of nm23-H1 and nm23-H2 on proliferation properties of head and neck tumor cells. The proliferation rate of transfected cells was evaluated using EGFP reporter system and flow cytometry. HEp-2 and CAL 33 cells transiently transfected with nm23 cDNA containing constructs exhibited enhanced proliferation. CAL 27 cells constitutively expressing GFP-Nm23-H2 protein, exhibited intense proliferation the first day after seeding, while the GFP-Nm23-H1 expressing clone started to proliferate after one-day lag period. The results on transiently transfected HEp-2 and CAL 33 cells generally confirmed previous findings connecting nm23 expression with altered proliferation of head and neck tumors. We speculate that the effects observed on stably transfected CAL 27 clones are due to their different attachment properties

Rho Family of Ras-Like GTPases in Early-Branching Animals

Non-bilaterian animals consist of four phyla ; Porifera, Cnidaria, Ctenophora, and Placozoa. These early-diverging animals are crucial for understanding the evolution of the entire animal lineage. The Rho family of proteins make up a major branch of the Ras superfamily of small GTPases, which function as key molecular switches that play important roles in converting and amplifying external signals into cellular responses. This review represents a compilation of the current knowledge on Rho-family GTPases in non-bilaterian animals, the available experimental data about their biochemical characteristics and functions, as well as original bioinformatics analysis, in order to gain a general insight into the evolutionary history of Rho-family GTPases in simple animals

Sponges: A Reservoir of Genes Implicated in Human Cancer

Recently, it was shown that the majority of genes linked to human diseases, such as cancer genes, evolved in two major evolutionary transitions—the emergence of unicellular organisms and the transition to multicellularity. Therefore, it has been widely accepted that the majority of disease-related genes has already been present in species distantly related to humans. An original way of studying human diseases relies on analyzing genes and proteins that cause a certain disease using model organisms that belong to the evolutionary level at which these genes have emerged. This kind of approach is supported by the simplicity of the genome/proteome, body plan, and physiology of such model organisms. It has been established for quite some time that sponges are an ideal model system for such studies, having a vast variety of genes known to be engaged in sophisticated processes and signalling pathways associated with higher animals. Sponges are considered to be the simplest multicellular animals and have changed little during evolution. Therefore, they provide an insight into the metazoan ancestor genome/proteome features. This review compiles current knowledge of cancer-related genes/proteins in marine sponges

Genetics of Marine Organisms Associated with Human Health

Marine habitats harbour a large variety of organisms that belong to diverse taxa ; from bacteria and unicellular eukaryotes to fungi, animals, and plants. Although we have only started to understand the diversity and structure of marine communities, it is clear that numerous marine species have or might have an impact on human health. Some are a source of natural products with potential or actual medical applications, others are toxic and harmful to humans, and some are used in biomedical research to help understand the molecular basis of human diseases. New molecular genetics and genomic methods provide powerful and ever more indispensable tools for studying marine organisms and all aspects of their influence on human health. Herein, we present work using the latest research, which mostly uses genomics, to tackle the questions related with the topic of the issue

Reversibility of Membrane N-Glycome of HeLa Cells upon Treatment with Epigenetic Inhibitors

Glycans are essential regulators of protein function and are now in the focus of research in many physiological and pathophysiological processes. There are numerous modes of regulating their biosynthesis, including epigenetic mechanisms implicated in the expression of glyco- genes. Since N-glycans located at the cell membrane define intercellular communication as well as a cellular response to a given environment, we developed a method to preferentially analyze this fraction of glycans. The method is based on incorporation of living cells into polyacrylamide gels, partial denaturation of membrane proteins with 3 M urea and subsequent release of N-glycans with PNGase F followed by HPLC analysis. Using this newly developed method, we revealed multiple effects of epigenetic inhibitors Trichostatin A, sodium butyrate and zebularine on the composition of N- glycans in human cells. The induced changes were found to be reversible after inhibitor removal. Given that many epigenetic inhibitors are currently explored as a therapeutic strategy in treatment of cancer, wherein surface glycans play an important role, the presented work contributes to our understanding of their efficiency in altering the N-glycan profile of cancer cells in culture

The utilization of pEGFP reporter system in cell-cycle analysis of adherent cells

Background and Purpose: GFP (green fluorescent protein) is widely used in a variety of fluorescent methods aimed at revealing the fate of proteins in the cell, intracellular transport, transfection efficiency and is also recommended for cell-cycle analysis purposes. In our attempt to evaluate the role of nm23 genes in proliferation of head and neck tumor cells in culture we have decided to use EGFP reporter system and analyze the DNA content by flow cytometry. Materials and Methods: To optimize the method we either transiently transfected the cells with pEGFPC1-nm23 constructs or cotransfected the cells with an nm23 carrying constructs and pEGFPC1 as a reporter system. We established stable clones with pEGFPC1-nm23 constructs and analyzed them by flow cytometry, as well. Results and Conclusions:We report our experience for the use of pEGFP reporter system and flow cytometry for determining cell-cycle distribution of transiently and stably transfected adherent tumor cells. We discuss, in brief, the protocol we used and the problems that appeared during our experiments – GFP bleaching, cell clumping and degradation and insufficient number of cells to be analyzed. In conclusion, we suggest useful tips how to avoid or minimize the technical problems of this method and improve the results and analysis