[Human Papillomavirus - Role in Cervical Carcinogenesis and Methods of Detection]. / Lidský papilomavirus - role v karcinogenezi cervixu a moznosti jeho detekce.

BACKGROUND: Persistent infection with high-risk human papillomavirus (HPV) strains, especially HPV 16 and HPV 18, is associated with the onset of various malignant diseases, including cervical carcinoma in women. HPV DNA testing is thus being implemented as a complementary method to standard cytological examination, mainly due to its increased sensitivity. AIM: This review outlines the role of HPV in cervical carcinogenesis, with a focus on the formation of cervical intraepithelial neoplasias (CIN1-3) and the molecular mechanism underlying cellular transformation. Current biomarkers used to screen premalignant lesions are described, including mRNA transcripts of the E6 and E7 genes, protein p16 (a cyclin-dependent kinase inhibitor that regulates cell cycle progression from G1 to S phase), altered DNA methylation patterns, and actions of specific microRNAs (short (18-22 bp), non-coding, single-stranded RNA molecules that regulate gene expression at the post-transcriptional level). This review also describes the advantages and drawbacks of commercial HPV tests, and depicts novel methods for more cost-effective and faster HPV diagnostics based on optical or electrochemical detection. CONCLUSION: Although great progress has been made, the incidence and mortality rates of cervical malignancies remain relatively high, especially in developing countries. Incorporation of HPV testing into routine screening programs could help to decrease mortality rates; however, the cost of such testing must be reduced if it is to compete with current cytology-based examinations.Key words: HPV - cervical carcinoma - HPV testing - nucleic acid hybridization - mRNA - DNA methylation - microRNA This work was supported by MEYS-NPS I-LO1413 and GACR 17-08971S. 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: 25. 9. 2017Accepted: 26. 1. 2018.

Selective elimination of neuroblastoma cells by synergistic effect of Akt kinase inhibitor and tetrathiomolybdate.

Neuroblastoma is the most common extracranial solid tumour of infancy. Pathological activation of glucose consumption, glycolysis and glycolysis-activating Akt kinase occur frequently in neuroblastoma cells, and these changes correlate with poor prognosis of patients. Therefore, several inhibitors of glucose utilization and the Akt kinase activity are in preclinical trials as potential anti-cancer drugs. However, metabolic plasticity of cancer cells might undermine efficacy of this approach. In this work, we identified oxidative phosphorylation as compensatory mechanism preserving viability of neuroblastoma cells with inhibited glucose uptake/Akt kinase. It was oxidative phosphorylation that maintained intracellular level of ATP and proliferative capacity of these cells. The oxidative phosphorylation inhibitors (rotenone, tetrathiomolybdate) synergized with inhibitor of the Akt kinase/glucose uptake in down-regulation of both viability of neuroblastoma cells and clonogenic potential of cells forming neuroblastoma spheroids. Interestingly, tetrathiomolybdate acted as highly specific inhibitor of oxygen consumption and activator of lactate production in neuroblastoma cells, but not in normal fibroblasts and neuronal cells. Moreover, the reducing effect of tetrathiomolybdate on cell viability and the level of ATP in the cells with inhibited Akt kinase/glucose uptake was also selective for neuroblastoma cells. Therefore, efficient elimination of neuroblastoma cells requires inhibition of both glucose uptake/Akt kinase and oxidative phosphorylation activities. The use of tetrathiomolybdate as a mitochondrial inhibitor contributes to selectivity of this combined treatment, preferentially targeting neuroblastoma cells.

Current Methods of microRNA Analysis.

BACKGROUND: MicroRNA (miRNA) are a class of short non-coding RNA molecules that regulate gene expression at the post-transcription level by binding to mRNA. By affecting many physiological processes, including cellular proliferation, differentiation, and apoptosis, they have a major impact on the development of cancer as well as other diseases. Hence, miRNAs could serve as potential tumor biomarkers in e.g. early diagnostics, predicting responses to therapy, monitoring relapse, and molecular classification of tumors. AIM: miRNA detection requires various sophisticated strategies due to the small size, sequence similarity among family members, and often very low levels of miRNAs in analyzed samples. This review describes standard techniques of miRNA detection, such as the reverse transcriptase polymerase chain reaction, microarrays, and next-generation sequencing, and compares several commercially available detection kits. Major emphasis is given to newly developed technologies and methods, which could make the analysis cheaper and quicker. We present, for instance, alternative amplification techniques (isothermal amplification and the hybridization chain reaction), different types of nanomaterials, special proteins used in miRNA analysis, and a number of biosensors utilizing optical or electrochemical detection. CONCLUSION: The importance of miRNA has led to a huge increase in the number of new methods. Most of them, however, have not been tested on clinical material, and thus it is difficult to assess their potential usefulness in routine practice. Their commercial application strongly depends on strict validation with standard techniques using not only model systems, but also clinical samples. Key words: microRNA - gene expression regulation - tumour biomarkers - reverse transcription PCR - biosensors This work was supported by MEYS - NPS I - LO1413 and GAČR 17-08971S. 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: 9. 7. 2018.

Genomagnetic LAMP-based electrochemical test for determination of high-risk HPV16 and HPV18 in clinical samples.

Major cause of cervical cancer is a persistent infection with high-risk types of human papillomaviruses (HPV). For that reason, HPV testing is now becoming an important addition to standard cytological screening of cervical malignancies in women (known as Pap test). New methods are sought which could offer rapid and inexpensive detection schemes, such as those based on electrochemical (EC) readout. Here, we developed an assay for parallel detection of two most oncogenic high-risk HPV types, HPV16 and HPV18, by combining loop-mediated amplification (LAMP) of template DNA, its separation using magnetic beads and detection with amperometry at carbon-based electrode chips. Our EC-LAMP test enabled us to successfully discriminate both HPV types not only in cancer cell lines, but also using clinical material obtained from HPV-positive patient samples.