Olga Kovaleva

Dr. Olga Kovaleva

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Research Focus & Metrics

Academic Career Length

13Years (2014-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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13 September 2020 in Biomedicines
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Journal Article
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OKOlga Kovaleva
Olga Kovaleva
Polina PodlesnayaPolina Podlesnaya
Polina Podlesnaya
MRMadina Rashidova
Madina Rashidova
DBDaria Bykova
Daria Bykova
APAnatoly Petrenko
Anatoly Petrenko
Alexei GratchevAlexei Gratchev
Alexei Gratchev
The link between a lung tumor and the lung microbiome is a largely unexplored issue. To investigate the relationship between a lung microbiome and the phenotype of an inflammatory stromal infiltrate, we studied a cohort of 89 patients with non-small cell lung cancer. The microbiome was analyzed in tumor and adjacent normal tissue by 16S rRNA amplicon sequencing. Characterization of the tumor stroma was done using immunohistochemistry. We demonstrated that the bacterial load was higher in adjacent normal tissue than in a tumor (p = 0.0325) with similar patterns of taxonomic structure and alpha diversity. Lung adenocarcinomas did not differ in their alpha diversity from squamous cell carcinomas, although the content of Gram-positive bacteria increased significantly in the adenocarcinoma group (p = 0.0419). An analysis of an inflammatory infiltrate of tumor stroma showed a correlation of CD68, iNOS and FOXP3 with a histological type of tumor. For the first time we showed that high bacterial load in the tumor combined with increased iNOS expression is a favorable prognostic factor (HR = 0.1824; p = 0.0123), while high bacterial load combined with the increased number of FOXP3+ cells is a marker of poor prognosis (HR = 4.651; p = 0.0116). Thus, we established that bacterial load of the tumor has an opposite prognostic value depending on the status of local antitumor immunity.

12 March 2014 in Cell Cycle
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Journal Article
Closed access
YKYaroslav Kainov
Yaroslav Kainov
IFIrina Favorskaya
Irina Favorskaya
VDVera Delektorskaya
Vera Delektorskaya
GCGalina Chemeris
Galina Chemeris
AKAndrei Komelkov
Andrei Komelkov
Elena M TchevkinaElena M Tchevkina
Elena M Tchevkina
CRABP1 (cellular retinoic acid binding protein 1) belongs to the family of fatty acid binding proteins. Retinoic acid binding is the only known functional activity of this protein. The role of CRABP1 in human carcinogenesis remains poorly understood. Here, for the first time we demonstrated pro-metastatic and pro-tumorigenic activity of CRABP1 in mesenchymal tumors. Further functional analysis revealed that the pro-tumorigenic effect of CRABP1 does not depend on retinoic acid binding activity. These results suggest that CRABP1 could have an alternative intracellular functional activity that contributes to the high malignancy of transformed mesenchymal cells. Microarray analysis detected CRABP1-mediated alterations in the expression of about 100 genes, including those encoding key regulatory proteins. CRABP1 is ubiquitously expressed in monophasic synovial sarcomas, while in biphasic synovial sarcomas it is expressed uniquely by the spindle cells of the aggressive mesenchymal component. High level of CRABP...

20 October 2015 in EPMA Journal
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Journal Article
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AMAmanda Mickley
Amanda Mickley
OKOlga Kovaleva
Olga Kovaleva
Julia KzhyshkowskaJulia Kzhyshkowska
Julia Kzhyshkowska
Alexei GratchevAlexei Gratchev
Alexei Gratchev
Kidney cancer is one of the deadliest malignancies due to frequent late diagnosis (33 % or renal cell carcinoma are metastatic at diagnosis) and p

27 June 2022 in Biomedicines
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OKOlga Kovaleva
Olga Kovaleva
Polina PodlesnayaPolina Podlesnaya
Polina Podlesnaya
MSMaxim Sorokin
Maxim Sorokin
VMValeria Mochalnikova
Valeria Mochalnikova
Vladimir KataevVladimir Kataev
Vladimir Kataev
Alexei GratchevAlexei Gratchev
Alexei Gratchev
The identification of new prognostic markers of renal cell carcinoma (RCC) is an urgent problem in oncourology. To investigate the potential prognostic significance of tumor microbiome and stromal inflammatory markers, we studied a cohort of 66 patients with RCC (23 clear cell RCC, 19 papillary RCC and 24 chromophobe RCC). The microbiome was analyzed in tumor and normal tissue by 16S rRNA amplicon sequencing. Characterization of the tumor stroma was performed using immunohistochemistry. A significant difference in alpha diversity was demonstrated between normal kidney tissue and all types of RCC. Further, we demonstrated that the bacterial burden was higher in adjacent normal tissue than in a tumor. For the first time, we demonstrated a significant correlation between bacterial burden and the content of PU.1+ macrophages and CD66b+ neutrophils in kidney tumors. Tumors with high content of PU.1+ cells and CD66b+ cells in the stroma were characterized by a lower bacterial burden. In the tumors with high bacterial burden, the number of PU.1+ cells and CD66b+ was associated with a poor prognosis. The identified associations indicate the great prognostic potential of a combined tumor microbiome and stromal cell analysis.

9 December 2011 in Journal of Cellular Biochemistry
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AKAnna V. Knizhnik
Anna V. Knizhnik
OKOlga V. Kovaleva
Olga V. Kovaleva
AKAndrei Komelkov
Andrei Komelkov
LTLuybov S. Trukhanova
Luybov S. Trukhanova
VRVera A. Rybko
Vera A. Rybko
Elena M TchevkinaElena M Tchevkina
Elena M Tchevkina

1 June 2021 in Journal of Physics: Conference Series
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Conference Paper
Open access
DBDmitry Bagrov
Dmitry Bagrov
ASAlexey Senkovenko
Alexey Senkovenko
INI I Nikishin
I I Nikishin
GSG O Skryabin
G O Skryabin
Pavel KopninPavel Kopnin
Pavel Kopnin
Elena M TchevkinaElena M Tchevkina
Elena M Tchevkina
Exosomes and microvesicles usually require characterization at the single-particle level. The most commonly used methods for this purpose are transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA). However, atomic force microscopy (AFM) is also a promising method for the characterization of exosomes, and its opportunities seem underestimated. Here we describe the characterization of exosomes isolated from the conditioned media of human placenta cells using AFM, TEM, and NTA; we focus on the technical aspects of AFM imaging and data processing.