The paper describes 2 cases of immature ovarian teratoma with elements of nephroblastoma (ICD-0 code 9080/3) in patients aged 61 and 70 years. Microscopic examination revealed that both cases had blastemal cells with scant cytoplasm and basophil nuclei sticking together. Epidermal, glandular, rhabdomyoblastic, chondroid, bone, neuroectodermal, and histiocytic components were determined. Papillary and glomeruloid structures and primitive tubules were immured in the sarcomatous stroma. Immunohistochemical studies showed a strong reaction with Wilms tumor 1 (WT1), paired box gene (PAX-2), cytokeratin 7, desmin, smooth muscle actin, and α-1 antitrypsin. The recurrent tumors displayed a 1.8- to 6.1-fold increase in the level of p53. At the same time, the molecular genetic study revealed p53 gene mutation. In both cases, serous ovarian cystadenocarcinoma was misdiagnosed, ineffective chemotherapy was performed, and a recurrence occurred. The literature review revealed only 8 such cases.

Oral cavity squamous cell carcinoma (OC-SCC) is the most common and aggressive malignancy of the oral cavity. Recent studies have revealed infections with human papilloma virus (HPV) as an additional risk factor for oral squamous cell carcinoma development, while distinguished role of Epstein-Barr virus (EBV) remains still uncertain. However, the evidence for association between virus infection and risk of oral squamous cell carcinoma is controversially and varies significantly by geographic regions and race.

Oncogenesis can be caused by an increase in the activity of genes responsible for initiating tumor growth in stem or progenitor cells, as well as a reduction in the functioning of suppressor genes. Endogenous estrogen exposure is associated with an increased risk of breast cancer in both pre- and postmenopausal women. The most important step in the understanding of the pathogenesis of breast cancer was the development of the theory of the switching of estrogen's effect from hormonal to genotoxic, in which the main culprits of carcinogenesis are not chemical metabolites of estrogens, but their derivatives, corresponding to chemical procarcinogens according to their damaging characteristics. The origin of these substances and the formation of estrogen genotoxicity lies in the disruption of the inactivation process of catechol estrogens in methylation reactions. The main epigenetic modification of the human genome is the methylation of cell DNA molecules. DNA methylation does not alter the primary sequence of nucleotides, but is necessary for the functional suppression of certain genes. The phenomenon of hypomethylation-hypermethylation underlies the long-term silencing of various genes, including tumor suppressor genes. Nutrition and a lifestyle associated with smoking and the consumption of excessive quantities of alcohol determine estrogen metabolism and the availability of methyl groups in the body, as well as epigenetic changes in the DNA of the genome. The assessment of individual risk of breast cancer on the basis of an assay for the expression and methylation of the COMT gene responsible for estrogen metabolism seems relevant.

In most cases, oncogene amplification are prognostic and predictive markers for various tumors, therefore DNA probes are unable to reveal changes in the copy numbers should not be used to diagnose malignant tumors.

Malignant cutaneous melanoma (CM) is an extremely aggressive cancer characterized by a high level of metastatic activity and unfavorable prognosis due to a high incidence of relapses, as well as resistance to standard chemotherapy. Cutaneous melanoma accounts for 80% of deaths from malignant skin tumors. Nucleolin/C23 and nucleophosmin/B23, which constitute altogether ~70% of the nucleolus volume, are promising targets for molecular therapy of melanoma. These proteins perform many important functions in the cell, so disruption of the NCL and/or NPM gene structure and abnormal expression of the C23 and B23 proteins they encode, can lead to unlimited cell proliferation and progression of a tumor. Therefore, investigation of the structure and expression of these genes is a topical problem, which is important for understanding the mechanisms of CM carcinogenesis and for the development of new therapeutic approaches. This paper describes new NCL and NPM polymorphisms, as well as the levels of C23 and B23 expression in normal tissues, CM and mucosal melanoma.

Acral melanoma is one of the most aggressive and fast-growing forms of cutaneous melanoma and is characterized by a predominant location on the palms and feet. Primary tumors, metastases, and normal tissue samples from five acral melanoma patients were examined by massive parallel sequencing, focusing on the coding regions of 4100 genes involved in the origin and progression of hereditary and oncology diseases. Somatic mutations were found in genes related to cell division, proliferation, and apoptosis (BRAF, NRAS, VAV1, GATA1, and GCM2); cell adhesion (CTNND2 and ITGB4); angiogenesis (VEGFA); and the regulation of energy metabolism (BCS1L). Comparisons of target DNA sequences between morphologically normal and primary tumor tissues and between normal and metastatic tissues identified the candidate genes responsible for rapid metastasis in acral melanoma.

Carotid paragangliomas (CPGLs) are rare neuroendocrine tumors of the head and neck. "Germline" and somatic mutations in a number of genes were shown to be associated with the development of CPGLs; however, molecular mechanisms of the tumor pathogenesis have not been fully understood. In the work, we have used whole exome sequencing data of 52 CPGLs obtained earlier. Using MutSigCV, the search for genes with high mutation rate was performed. Thirty four genes (MADCAM1, SARM1, ZFPM1, CTDSP2, DSPP, POTED, ANP32B, FRG2B, BAGE3, CCDC89, ACOT2, KRTAP10-1, ATXN1, GXYLT1, MUC2, AQP7, TMPRSS13, KRTAP4-3, PRR21, PSPH, PLBD1, ZNF595, IGSF3, PRR16, FAM157A, KCNJ12, HYDIN, IGFBP2, KIAA1671, DISC1, MUC6, XKR3, HRNR, and MUC4) potentially associated with the CPGL initiation and progression were revealed. The involvement of these genes in the pathogenesis of CPGLs was first shown, and possible mechanisms of their participation in that were discussed.

To identify the expression of the molecular markers p53 and p16INK4A in head and neck squamous cell carcinoma (HNSCC) and to assess their impact on its clinical and morphological characteristics and overall survival (OS) rates in patients with HNSCC.

BRCA1 (breast cancer 1) protein is involved in the genome stability maintenance participating in homologous recombination-dependent DNA repair. Disruption of BRCA1 functioning is associated with breast and ovarian cancer. Despite the important role of BRCA1 in DNA repair in all cell types, the development of BRCA1-associated cancer takes place mainly in estrogen-dependent tissues such as breast and ovarian ones. Using breast cancer cell line MCF-7 it was demonstrated in in vitro experiments that the estrogen 17β-estradiol (E2), phytoestrogens (genistein and apigenin) and antiestrogens (tamoxifen and fulvestrant) inhibited estrogen receptor (ERα) expression while only genistein influenced BRCA1 increasing its expression. In hypoxia, that is an important factor of solid tumors progression, the decrease of BRCA1 and ERα expression was demonstrated in MCF-7 cells. Therefore, hypoxia influences both BRCA1-dependent DNA repair and hormonal regulation of breast cancer cell growth. Taken together, obtained results demonstrate a relationship between BRCA1 and steroid hormones signal transduction pathways in breast cancer cells and point out to the importance of complex BRCA1 and ERa expression regulation mechanisms studies including epigenetic gene expression regulation.

Placenta is a highly specialized organ that is necessary for successful gestation. Several models of the placental barrier are used to study how it functions, including the transplacental transport of xenobiotics. One of these models, human choriocarcinoma cell line BeWo is widely used in vitro. Notably, cancerous BeWo cells form multilayer structures that normally are not found in the human placenta. Here, we aim to develop techniques suitable for monitoring BeWo b30 cells in culture. To assess the state of BeWo b30 cells growing on a membrane, we use impedance spectroscopy, which allows us to estimate the number of cell layers by the change in the electrical parameters of the biological system. In mature BeWo b30 cell cultures, we also note a significant increase in the expression of genes encoding metallothioneins (particularly, MT1B, MT1F, and MT2A) and syncytins (ERVW-1 and ERVFRD-1), which can be used as biomarkers reflecting the development of mature phenotypic characteristics, namely, trophoblastic invasion and formation of the syncytium.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the only curative therapy for hematopoietic malignancies. The graft-derived donor lymphocytes are capable of eliminating the residual recipient malignant cells in the course of allogeneic immune response, thus decreasing the chances of a relapse of the disease. Foreign peptides of the recipient presented by the MHC molecules are able to elicit the immune response immunologically. These polymorphic peptides are known as minor histocompatibility antigens (MiHAs). MiHAs occur due to the nonsynonymous single nucleotide polymorphisms in human genome. Transfusion of T cells specific to MiHAs presented predominantly in the cells of hematopoietic origin will allow the targeted elimination of residual malignant clones avoiding undesirable damage to healthy tissues. To induce the immune response, the donor must be homozygous by the MiHA allele and the recipient must either be homozygous or heterozygous by the alternative MiHA allele. The therapeutic mismatch occurs in 25% of cases under the optimal frequency of allelic variants. Minor antigen ACC-1Y originates from polymorphism in the BCL-2A1 gene; its immunogenic mismatch occurrence approaches the theoretical maximum. In addition, BCL2A1 is overexpressed in cells of various lymphomas. ACC-1Y is presented on allele HLA-A*24:02, which is relatively frequent in the Russian population. Combination of these factors makes the minor antigen ACC-1Y a promising target for immunotherapy. Transfusion of donor CD8^(+) lymphocytes modified with transgenic MiHA-specific TCR is one of the promising methods of posttransplant leukemia therapy and relapse prophylaxis. We obtained a sequence of high-affinity ACC-1Y-specific TCR after the antigen-specific expansion of T cells derived from a healthy ACC-IY^(-/-) donor. We cloned this sequence into the lentiviral vector and obtained the assembled viral particles. Further, we transduced the CD8^(+) lymphocyte culture and demonstrated its antigen-specific cytotoxic activity. It is suggested that CD8^(+) lymphocytes modified by the described method could be potentially transferred to recipients as a therapy against relapse after allo-HSCT.

miRNA genes play an important role in cancer pathogenesis, while they may be suppressed by hypermethylation. Here, we assess the diagnostic potential of a group of hypermethylated miRNA genes (MIR-124-1, MIR-124-3, MIR-125B-1, MIR-127, MIR-132, MIR-193a, and MIR-34b/c) in a representative set of 70 breast cancer samples and 17 breast tissue samples from deceased donors with no malignancies. For these seven genes, the methylation status is determined using the methylation-specific PCR. Methylation reached 26-76% in tumor specimens, 1-27% in paired considered normal breast tissues, and 0-18% in breast tissue from deceased donors. By quantitative RT-PCR, reduced expression levels of the investigated miRNAs are detected, with a negative correlation of expression levels with gene hypermethylation. Combinations of three or four hypermethylation biomarkers, namely, MIR-124-1, MIR-125B-1, MIR-127, and MIR-34b/c are found suitable for breast cancer diagnostics; with sensitivity (76-93%), specificity (88-100%), and AUC (0.88-0.94). Notably, the MIR-127 gene was hypermethylated only in the tumor samples of patients with metastases, and, therefore, should be tested as a marker of breast cancer dissemination. These findings may lead to improvement in the management of breast cancer.

The discovery of novel significant molecular and genetic markers is important for the diagnostics, prognosis, and therapy selection in hematological malignancies. Distinct cytogenetic aberrations leading to the formation of fusion genes are found in more than 40% of pediactric cases of acute myeloid leukemia (AML); however, the tumor cells in approximately 20% of these patients display cytogenetically normal karyotype (NK-AML). Here we present the analysis of the mutational profiles of leukemic cells collected from pediatric AML cases without known clinically significant chromosomal aberrations aimed at identifying AML specific markers. In 34 pediatric cases of different AML types, the coding regions of 26 genes involved in the AML pathogenesis were analyzed by massive parallel sequencing. Sequencing revealed the somatic mutations in genes that are involved in various intracellular signaling pathways, including the CEBPA, ETV, IDH1, JAK2, and NRAS genes. In addition, rare genetic variants were found in CUX1, FLT3, TET2, PTPN11, and NUP98 genes. This data may contribute to the understanding of the mechanisms of malignant cell transformation in the case of leukemogenesis.

In the article the main mechanisms of molecular pathogenesis of urinary tract urothelial carcinoma are presented. Two different molecular pathways that determine the development of non-invasive and invasive urothelial carcinoma, the immunohistochemical spectrum of stem markers and aspects of the carcinogenesis of multifocal and recurrent tumors are considered.

Prostate cancer is the second leading cause of cancer death. The widespread introduction into the clinical practice of test for prostate specific antigen (PSA) led to an increase in the number of prostate biopsies performed. At the same time, a decrease in the threshold of age-specific PSA standards has resulted in an increase in the number of unnecessary biopsies. In this regard, a need has arisen for new prostate cancer biomarkers. PCA3 is a non-coding mRNA that is exclusively expressed by prostate cells. Currently, three generations of test diagnostic systems based on the quantitative analysis of the PCA3 mRNA in the urine or its cell sediment has already developed, and they differ in the type of material studied and the method for estimating the amount of PCA3 mRNA. Clinical studies of the developed test systems have shown that a high level of PCA3 expression in the patients urine correlates with the probability of detecting prostate cancer. PCA3 test has higher positive and negative predictive values than previously used PSA test. These data are repeatedly confirmed by studies conducted in different clinics. Thus, the introduction of the method of quantitative determination of PCA3 in clinical practice can significantly improve the efficiency of diagnosis of prostate cancer and reduce the number of unnecessary biopsies.

The paper describes a clinical case of atypical teratoid/rhabdoid tumor with preserved INI1 expression and SMARCA4 gene mutations in an 8-month-old girl. Genome-wide DNA methylation, hierarchical clustering, and next-generation sequencing were used to make a tumor diagnosis. However, BRG1 immunohistochemical examination may be recommended in the routine practice of diagnosis and study of childhood CNS malignant tumors.

To study the expression of the anti-apoptotic survivin protein, as well as the expression of the BIRC5 gene of its encoding primary breast carcinoma as a potential procnostic and predictive marker.

Papillary carcinoma is the most commonly diagnosed form of well-differentiated thyroid cancer that is generally characterized by a favorable prognosis. However, a number of relatively rare variants of this tumor, such as papillary carcinoma of high cells, papillary carcinoma of columnar cells, a diffuse sclerosing variant and recently described cancer of shoe nail cell type, are characterized by a less favorable clinical course, a high frequency of distant metastasis, and relatively low overall and relapse-free survival rates. In this connection, it is important to recognize these options at the stage of a primary morphological study. This review of the literature considers the morphological, clinical and molecular genetic features of the above variants of papillary thyroid carcinoma.

A genotyping procedure based on single-step PCR and subsequent allele-specific hybridization on a hydrogel biochip was developed to address the polymorphisms of HERC2, OCA2, SLC24A4, SLC45A2, TYR, IRF4, MC1R,MITF, PIGU, MYH7B, NCOA6, and CDK10. Amplified gene fragments were fluorescently labeled in PCR, and fluorescent signals from biochip cells were detected to evaluate how efficiently the PCR product formed a perfect duplex with an immobilized probe. The analytical characteristics of hybridization analysis were estimated for several fluorophores with different optical spectra. Cyanine dyes fluorescing in the range of Cy5 and Cy7 were synthesized for the purpose and used as 5'-tags of universal primers in single-step PCR. A Cy7 analog fluorescing in the near infrared range was found to increase the sensitivity of hybridization analysis by producing a lower background signal in the cases where target gene amplification was low.

The noncoding part of the human genome, which was previously considered nonfunctional or junk DNA, has been the subject of extensive research this decade. Nevertheless, long noncoding RNAs still represent one of the least investigated fields because of their complexity, multiplicity, and diversity. While some long noncoding RNAs have been characterized fairly well, the functions of many others remain poorly understood. Long noncoding RNAs play an essential role in the regulation of gene expression in all tissues and on all developmental stages. They are involved in a number of signaling pathways, and their aberrant functioning can be pathogenic. This review aims to summarize current state-of-the-art structures of these transcripts in this research field, their genomic localization, their functions, and underlying mechanisms. It also focuses on cancer-associated aberrations of long noncoding RNAs, as well as on prospects of their application in tumor diagnostics and therapy. Examples of decreasing the levels of oncogenic long noncoding RNAs via silencing with short interfering RNAs, antisense oligonucleotides, or low molecular-weight inhibitors are also described.