The recombinant proteins E6-CBD and E7-CBD, which are antigens E6 and E7 of human papillomavirus type 16 (HPV16), were connected by a glycine-serine spacer with the cellulose-binding domain (CBD) of
...Anaerocellum thermophilum
in preparations obtained via synthesis in a heterologous expression system in
Escherichia coli
. A simple, effective, one-step technology for the isolation and purification of recombinant proteins E6-CBD and E7-CBD has been developed. The presence of antigenic properties in the obtained protein preparations was confirmed via Western blot. Three variants of immunogenic compositions with the recombinant proteins E6-CBD and E7-CBD and a three-dose immunization scheme have been developed. The immunogenicity was assessed in the BALB/c mice, and the antitumor effect of immunogenic compositions was studied on an experimental model of BALB/c mice with HPV16-associated tumors. It is shown that E6-CBD and E7-CBD are highly immunogenic and have antitumor effects in vivo. Both proteins, E6-CBD and E7-CBD, must be present to achieve the highest efficiency as part of the immunogenic composition. The obtained HPV16 recombinant antigens E6-CBD and E7-CBD can be used in two ways: (
a
) in clinical practice as the main specific components of therapeutic vaccines for the treatment of HPV16-associated neoplastic lesions of various localizations (cervical cancer, carcinoma of the anogenital tract, oropharynx) and (
b
) in diagnostics for the development of diagnostic kits to detect antibodies to E6 and E7 oncoproteins in patients with HPV16-associated malignant neoplasms.
Full text
Available for:
DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
High-risk human papillomaviruses (HR-HPVs) can be detected in a proportion of non-melanoma skin cancers. Data on prevalence are inconclusive, but are essential to estimate the relevance of HR-HPV, ...particularly with regard to prophylactic HPV vaccines for skin cancer prevention.
High-risk human papillomavirus DNA was investigated in 140 non-melanoma skin lesions from 54 immunocompetent patients and 33 immunosuppressed renal allograft recipients. Expression of p16(INK4a), a marker for HR-HPV oncogene expression in the uterine cervix, and of p53 and pRB was evaluated immunohistochemically.
The highest prevalence of HR-HPV was found in squamous cell cancer (SCC) (46.2% (6 out of 13) in immunosuppressed and 23.5% (4 out of 17) in immunocompetent patients). High-risk human papillomavirus positivity was accompanied by diffuse p16(INK4a) expression in most SCC (P<0.001) and basal cell cancers (P=0.02), while almost all SCC in situ were p16(INK4a) positive irrespective of HR-HPV presence (P=0.66). Diffuse p16(INK4a) expression was associated with lack of pRB expression (P=0.001). p53 was strongly expressed in 40.0% (56 out of 140) of the lesions irrespective of HR-HPV presence.
High-risk human papillomavirus can be detected in lesions of keratinised squamous epithelia. The association of HR-HPV with diffuse p16(INK4a) expression might indicate HR-HPV oncogene expression in a proportion of lesions. Overexpression of p53 suggests p53 pathway alterations in HR-HPV-positive and -negative lesions.
Full text
Available for:
DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The article analyses data from the August Counts of 2018 and 2021, which covered the 40 most important wetlands on the Azov-Black Sea coast of Ukraine. Of the 106 wetland bird species recorded during ...the censuses, 35 species are listed in the Red Data Book of Ukraine. The number of them was about 50 thousand individuals or 7.6 % of the total number of counted birds: in 2018 — 24.1 thousand individuals and in 2021 — 25.8 thousand individuals. Detailed information on the number of bird species and the list of the most important sites for each species can be found in the publication. The comparison of the current data with the previous survey period 2004‒2015 (Chernichko et al., 2018) showed that the abundance of 17 waterbird species decreased, and 7 species increased their abundance. It is assumed that these changes are caused by the aridification of the climate, leading to the drying out of the shallow parts of the region's wetlands in the second half of the summer.
Molochnyi Liman is the largest liman (22,000ha) at the northern coast of the Sea of Azov. Contrary to estuaries, it is an ecotone without typical tides. It is a half-closed water body, with a ...connection to the Sea of Azov that has periodically renewed or ceased over the course of time. Molochnyi Liman is a wetland of international importance, a hydrological reserve of state significance and is part of the Pryazovskyi National Natural Park. The results of our research have established that termination of the liman/sea connection has led to significant hydrological changes. The most crucial is a reduction in the liman's depth, accompanied with shrinkage in the water surface area, a dramatic increase in salinity to 95g/l and the loss of several Ramsar criteria. Restoration of the Molochnyi Liman ecosystem requires a positive water balance. There is a need for ensuring the inflow of at least 100mlnm3 of marine water into the liman through a connecting channel. This will renew normal functioning of the liman and reduce the salinity to an optimal level. The methodical approach used in this work can also be applied to other closed and half-closed water bodies of the Azov-Black Sea Region. The development of a hydrological model can be effectively used as a supportive tool for the management of the Tylihulskyi, Khadzhibeiskyi and Kuyalnytskyi limans in the north-western part of the Black Sea.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
In this review, we described human small DNA viruses discovered on the cusp of the 20th and 21st centuries as a result of cutting-edge technologies established in molecular biology. The problems of ...obtaining an evidence of the etiological role of new viruses in human diseases have been considered.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Infections with high-risk human papillomaviruses (HPV) are the etiological factor of certain types of human cancers in anogenital tract and head and neck cancers. Extensive epidemiological studies ...demonstrated the association of persistent high-risk HPV infection and the later development of cervical and other cancers. Experimental data using cell lines models and cervical cancers demonstrate that in more than 99 % of clinical samples the viral E6 and E7 genes are retained and expressed. These genes can transform human cells and inhibition of their expression in cancer cells results in loss of neoplastic growth properties. Molecular mechanisms of immortalization and transformation by E6 and E7 have extensively been investigated. However, the mechanism of E6 and E7 deregulation that triggers the shift from permissive infection to neoplastic transforming infection is still unclear. This review describes the current knowledge about the viral life cycle and discusses the molecular mechanisms that potentially allow the virus to escape its normal control and may trigger neoplastic progression. The molecular clarification of these events required for transformation of HPV-infected cells into cancer will provide a basis for conceptually novel diagnostic and therapeutic strategies and approaches.
T35 Kisseljov, F; Vinokurova, S; Kisseljova, N ...
European journal of cancer supplements,
11/2015, Volume:
13, Issue:
1
Journal Article
Peer reviewed
Open access
Epigenetics investigates mechanisms that control inheritance of gene expression program during somatic cell divisions. These mechanisms include regulation by DNA methylation, histone ...post-translational modifications and nucleosome positioning, functioning of regulatory non-coding RNAs, control of alternative splicing of mRNA precursors and high-order chromatin organization. Genome-wide loss of epigenetic stability and increased epigenetic plasticity are common features of all tumor types. In normal tissues epigenetic plasticity allow cells to response on environment signals. Thus, in tumor cells its constitutive activation leads to epigenetic heterogeneity that are the additional hallmark of the most of the classical cancers. Cervical cancers are one of the most interesting models for the analysis of the role of epigenetic changes in tumor progression. These types of tumors are associated with infection of human papilloma viruses of so-called high-risk group (HR-HPV) and characterized by well-defined stages of malignant conversion from intraepithelial neoplasias to carcinomas. The viral DNA can persist in episomal form or integrates into the host-cell genome. Cellular genomes encode genetic information in their linear sequence, but appropriate gene expression requires chromosomes to fold into dynamic complex three-dimensional structures. Scaffold/matrix attachment regions (S/MARs) are specialized genomic DNA sequences that take part in organization of these structures. We demonstrated that methylation of S/MARs was required for their attachment to nuclear matrix and that methylation status of S/MARs was changed in cervical cancer cell compared to normal cells. DNA methylation plays an important role in the regulation of gene expression. We found that methylation of the regulatory sequences in the HPV16 genome specifically changes in transformed compared to the normal cervical epithelial cells. Next, we showed that methylation of the transcription factor binding sites modulates the viral oncogene expression. These data suggest that the HPV16 genome methylation may represent an important mechanism that initiates the development of HPV-associated tumors. Using next generation sequencing, we identified pattern of differentially expressed microRNAs in clinical samples of the cervical lesions. We confirmed expression of microRNAs that have been described previously as well as identified new microRNAs that can be potentially involved in the development and progression of cervical cancer. Spectrum of differentially expressed microRNAs includes microRNAs targeting tumor-suppressor genes as well as oncogenes. Telomerase is a key regulator of cell proliferation. This enzyme is silent in normal cells and activated in most of the tumors. Few forms of RNA (hTERT), encoded by telomerase gene were detected in different tumor cells and among them three forms (alfa, beta and gamma) are most well pronounced. We found that in cervical tumors expression of all three forms are significantly increased. In some cases, we also observe higher level of hTERT expression in neighboring “normal tissue”. The correlation between expression levels of these three forms varied on different stages of the disease (three stages on intraepithelial neoplasias and carcinomas). The function of these three hTERT forms is still not well understood.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Background. Ovarian cancer is a complex and poorly studied disease that kills nearly 70–80 % of patients. Therefore, practitioners are interested in any opportunity of improving survival of these ...patients. From this point of view, investigation of genetic and epigenetic functions associated with this pathology is quite promising.Objective: to assess clinical and morphological characteristics of tumors in ovarian cancer patients, considering the presence of mutations and methylation in the BRCA1/2 gene.Materials and methods. This study included 180 ovarian cancer patients (FIGO stage I–IV) treated in the N. N. Blokhin Russian Cancer Research Center between 2008 and 2019. Study participants were divided into 3 groups according to their BRCA status and the number of primary tumors. We collected and analyzed venous blood, biopsy samples of ovarian cancer, archived histological sections, and paraffin-embedded tissue blocks. DNA isolated from venous blood was used to identify the following germline mutation by pyrosequencing: BRCA1 5382insC, BRCA1 4153delA, BRCA1 185delAG, and BRCA26174delT. DNA isolated from biopsy specimens and paraffin-embedded tissue specimens was used to analyze methylation in the promoter regions of the BRCA1 and BRCA2 genes by bisulfite sequencing (PyroMark Q24 DNA Sequencer; Qiagen, USA) with specific primers targeting promoter regions of the BRCA1 and BRCA2 genes.Results. Molecular testing demonstrated that the frequency of BRCA1 gene mutations was 21.1 % (38/148) in patients with solitary ovarian cancer and 40.6 % (13/32) in patients with multiple primary ovarian cancers. The frequency of methylation of the BRCA1 gene promoter was 2.2 % (18/148) in patients with solitary ovarian cancer and 3.1 % (1 case) in patients with multiple primary ovarian cancers. All BRCA1 methylated ovarian tumors were serous adenocarcinomas, including high grade tumors in 15 patients (78.9 %) and low-grade tumors in 4 patients (21.1 %).Conclusion. Hypermethylation of the BRCA1 gene promoter was observed only in individuals with sporadic serous ovarian cancer. No methylation was detected in patients with non-serous ovarian cancer, as well as in patients carrying BRCA1 gene mutations (both with solitary ovarian cancer and with primary multiple ovarian tumors).
The formation of wear-resistant powder surface coatings with slipping friction may be described by a statistical approach based on continuous Markov processes. The coordinates of the equilibrium ...frictional surface are shown to be normally distributed. The correlation of the parameters of surface wear is investigated.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
PDF
