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Background Non-steroidal anti-inflammatory drugs (NSAID) represent a group of medicaments inhibiting cyclooxygenase (COX) enzyme, and, in parallel, these drugs show also analgesic, antipyretic and anti-inflammatory effects. Due to their efficiency, good tolerance and easy availability, they belong to the worlds most used drugs. For decades, evidence of their anti-tumor activity has been growing, with the largest amount of published work being related to colorectal cancer (CRC). Based on both in vitro and in vivo experiments and data obtained from epidemiological and clinical studies, potential application of NSAID as chemo-preventive treatment for CRC patients is recently discussed in order to prevent development or recurrence of precanceroses and tumors. Promising treatment for such indication would be acetylsalicylic acid (ASA), which is the oldest, more than 100 years used member of the NSAID family. Nonselective irreversible COX inhibition is an important but probably not solely mechanism of its anticancer activity. Notably, wider use of ASA in chemoprevention is also prevented due to particular concerns about gastrointestinal and renal toxicity caused especially by its long-term use. Aims This review introduces the role of COX in tumor biology of CRC and highlights the results of the most interesting experiments illustrating the anti-tumor effect of ASA. Moreover, our work evaluates the most important published clinical analyzes of the ASA chemopreventive effect on CRC and discusses the current state. Key words: non-steroidal anti-inflammatory agents - acetylsalicylic acid - colorectal carcinoma - cyclooxygenase - chemoprevention This work was supported by the projects MEYS - NPS I - LO1413, MH CZ - DRO (MMCI, 00209805) and by Czech Science Foundation project no. 16-14829S. The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. Accepted: 10. 9. 2017.

Background Ferroptosis is a recently discovered type of cell death. It is genetically, morphologically, and biochemically distinct from other types of programmed cell death, such as necrosis, apoptosis, and autophagy. The level of intracellular free iron and reactive oxygen species formation are important for ferroptosis activation, which can occur through either of two key inhibitory processes. The first one involves inhibition of cystine transfer into cells by the cystine/glutamate antiporter system (Xc-). Cystine serves as a precursor for the synthesis of glutathione, a major cellular antioxidant. The second one involves the inhibition of glutathione peroxidase 4, which protects cells from lipid peroxidation. Ferroptosis is associated with many metabolic disorders, including neurological diseases and cancer. Molecules involved in the activation of ferroptotic pathways are involved in protecting cells against stress conditions, and in the maintenance of nicotinamide adenine dinucleotide phosphate and glutathione levels, as well as iron homeostasis. Also important is the connection with autophagy, so called ferritinophagy, in which iron is released from lysosomes into the cytosol. Cascade reactions of free unstable iron atoms with other molecules result in the production of reactive oxygen species that initiate the cellular stress that triggers ferroptosis. In diseases such as cancer where cell death inducing mechanisms, including apoptosis, are usually suppressed by genetic changes, the induction of alternative pathways leading to cell death could provide an attractive treatment strategy. Conclusion In recent years, research into new antimetastatic drugs has focused on the activation of alternative cell death pathways that might overcome disturbed metabolic processes inside cancer cells or the chemotherapy resistance acquired in the course of routine treatment. A number of molecules have been found to induce ferroptosis in tumor cells, suggesting that they may offer new alternatives for anticancer treatment. Key words: cell death - cancer - autophagy - ferroptosis - ferritinophagy - cellular stress - ROS This work was supported by the projects GACR 17-05838S, MEYS - NPS I - LO1413 and MH CZ- -DRO (MMCI, 00209805). The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. Accepted: 31. 8. 2018.

Background Due to the irreplaceable role of chemotherapy in cancer treatment, research has focused on improving the efficacies of individual drugs and minimizing, or completely suppressing, their negative side effects. Based on long-term experience and the results of clinical trials, the selection of appropriate treatment is currently based on classical clinical diagnostic criteria, such as tumor size, grade, and the presence or absence of standard markers. However, complications arise due to variability between patients and tumor heterogeneity. Characterization of intratumoral heterogeneity and acquisition of more reliable drug performance indicators should improve personalized therapy. Development and selection of suitable models are therefore important issues in cancer research focused on predicting sensitivity to therapy. Aim This work provides an overview of various chemosensitivity tests that have been previously employed and those that are currently used. Great emphasis is placed on comparing 2D and 3D cell culture models, since their importance and popularity are increasing. Particular attention is paid to in vivo systems, which have significantly improved recently and are tested in clinical trials to predict responses to therapy. Conclusion This work provides a brief overview of chemosensitivity tests, focusing on the importance of individual tests and their application in decision-making and patient stratification to improve the clinical responses of patients and the development of targeted personalized therapy.Key words: cell culture techniques - personalized medicine - drug screening - biological models - tumor cell lines - carcinoma - cytotoxicity assays This work was supported by the project MEYSNPS I-LO1413 and GACR 17-05838S. The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.Submitted: 21. 9. 2017Accepted: 20. 12. 2017.

Since its discovery, PCR has become a conventional method of molecular biology research laboratories and an indispensable tool in diagnostic medicine. Multiple variants of the PCR technique were developed, which enable the analysis of different bio-logical materials at different amounts and reaction conditions. This article briefly summarizes the PCR approaches and points out their applications in oncological research and practice.

Development of novel diagnostic and therapeutic approaches in cancer research requires sensitive and quantitative assays for determination of cancer associated proteins in clinical samples. Novel quantitative targeted proteomic approaches are overviewed in this communication. A major advantage of selected reaction monitoring (SRM) and pseudo- SRM lies in the selective and sensitive quantification of selected proteins in large sample sets. As such, they represent an alternative to immunochemical approaches. On the other hand, the potential of HRM and SWATH lies in recording of digital fingerprints, which enable post acquisition quantitative proteomic data mining on a similar basis to SRM. This article shows applications of targeted proteomics in a number of cancer research studies where they were used for quantification and validation of current or potential protein bio-markers and to study their role in cancer development and progression.

Migration and invasiveness are phenotypic characteristics of cells that contribute to physiological processes, such as wound healing or embryogenesis and they are involved in serious pathological processes, namely in tumor cell metastasis. Availability of methods for studying migration and invasiveness of the cells is important for understanding molecular basis of these processes. In the case of cancer, migration, invasiveness and metastatic potential of tumor cells are key factors that determine clinical prognosis of the patients. This communication provides an overview of in vitro and in vivo methods which are used to study cell migration, invasion and metastasis. In vitro meth-ods for studying cell migration include simple two dimensional assays (scratch - wound assay and the assay based on the effect of hepatocyte growth factor) and methods based on chemotaxis (Dunns chamber, videomicroscopy of cells, the use of carriers with chemoattractants). Methods for studying both cell migration and invasiveness in vitro include more complex systems based on the principle of the Boyden chamber (transwell migration/ invasive test, analysis of cell migration and invasion in xCELLigence system, confocal microscopy based approaches) as well as analysis of cell migration in microchannels. Our overview of in vivo methods provides an introduction into model organisms and methods used in this field, with an emphasis on the study of cancer metastasis in mouse models. The methods described in this review are mainly involved in larger research projects aiming at developing new diagnostic and therapeutic approaches in oncology.

The biological fate of each mRNA and consequently, the protein to be synthesised, is highly dependent on the nature of the 3′ untranslated region. Despite its non-coding character, the 3′ UTR may affect the final mRNA stability, the localisation, the export from the nucleus and the translation efficiency. The conserved regulatory sequences within 3′ UTRs and the specific elements binding to them enable gene expression control at the posttranscriptional level and all these processes reflect the actual state of the cell including proliferation, differentiation, cellular stress or tumourigenesis. Through this article, we briefly outline how the alterations in the establishment and final architecture of 3′ UTRs may contribute to the development of various disorders in humans.

In this study, we characterized the effects of LA-12 on tumor cell lines possessing wild type p53 and on p53-deficient/mutant cell lines and the results were compared to those obtained using cisplatin. We have determined changes of p53 levels, of its transcriptional activity, of its posttranscriptional modifications and the effect of the treatment on the cell cycle, on the induction of apoptosis and on gene expression. LA-12 induces weak accumulation of both transcriptionally active p53 tumor suppressor and of p21(WAF1/CIP1) protein. LA-12 and cisplatin also significantly differ in their effects on apoptosis and cell cycle and on gene expression spectra in studied cell lines. LA-12 induces higher apoptosis levels in comparison with those induced by cisplatin, especially in p53-deficient H1299 cells and in MCF-7DD cells with transcriptionally inactive p53. We suggest that LA-12-mediated apoptosis is not fully dependent on p53. This confirms the therapeutic potential of LA-12 as a more potent cytostatic agent for both tumor cells expressing wild type p53 and for p53-deficient or mutant cells.

Cancers are genetically and clinically very heterogeneous diseases; therefore, various proteomic studies have been trying to find bio-markers which can facilitate prognosis, diagnosis or treatment of these oncological diseases. The mass spectrometry is an effective tool for identification, quantitation, and characterization of biomolecules in the complex bio-logical samples. The first step suitable for selection of bio-markers called discovery proteomics provides a detailed analysis of the samples contributing to the identification of proteins, comparison of their presence in the samples, and selection of the convenient candidates for the prospective bio-markers. The next step of proteomics analysis is directed towards verification of chosen bio-markers with the approach called targeted proteomics. This technique evaluates presence and quantity of the proteins (biomarkers) in clinically precisely defined samples. This article focuses on the description of various approaches suitable for the quantitative analysis of the proteins connected with mass spectrometry.