Soluble forms of PD-1/PD-L immune checkpoint receptor and ligand in blood serum of breast cancer patients: association with clinical pathologic factors and molecular type of the tumor.

Results of enzyme-linked immunosorbent assay of the soluble forms of PD-1/PD-L immune checkpoint receptor and ligand (sPD-1 and sPD-L1) in pretreatment blood serum of 88 breast cancer patients at various disease stages aged 30-83 years are presented. The control group included 55 practically healthy women aged 19-82 years. Serum sPD-1 and sPD-L1 levels in breast cancer patients highly significantly (p<0.0001) differ from control and these changes are opposite: soluble receptor level is more than 6-fold decreased, while soluble ligand concentration - 5.5 fold increased. Both markers separately, as well as their ratio demonstrate very high sensitivity (94-100%) and specificity (95-100%) in relation to healthy control. No statistically significant associations of sPD-1 and sPD-L1 levels with clinical stage, individual TNM system criteria, tumor histological structure, grade, receptor status, and molecular type were established. In particular, no significant peculiarities of the markers' levels in triple negative breast cancer successfully treated with anti-PD-1/PD-L1 preparations were revealed. Long-term follow-up and dynamic studies of sPD-1 and sPD-L1serum levels in the course of treatment are required for evaluation of their independent from clinical and morphological factors prognostic significance and the possibility of application as low invasive tests for prediction and monitoring of corresponding targeted therapy efficiency.

[Hypermethylation of miR-107, miR-130b, miR-203a, miR-1258 Genes Associated with Ovarian Cancer Development and Metastasis].

It is known that microRNAs (miRNAs) are able to dynamically regulate gene expression. At the same time, methylation can reduce expression of miRNA encoding genes and, therefore, reduce their inhibitory effects on mRNAs of target genes, including those of oncogenes, that promoting the development of tumors of different localization. The role of miRNA hypermethylation in the pathogenesis of ovarian cancer is not completely understood; so we conducted a search for new hypermethylated and potentially suppressor miRNA genes in ovarian tumors. Four new miRNA genes (MIR-107, MIR-130b, MIR-203a, MIR-1258) commonly hypermethylated (28-52%) in tumor tissues vs 4-7% in paired histologically normal tissues, p < 0.01, were identified in a representative set of 54 ovarian cancer samples using methylation-specific PCR. It was shown that hypermethylation of MIR-130b, MIR-203a, and MIR-1258 genes is significantly (p < 0.05) associated with metastasis of ovarian cancer. These results suggest the involvement of four miRNAs (miR-107, miR-130b, miR-203a, and miR-1258) and hypermethylation of their encoding genes in the pathogenesis of ovarian cancer.

Matrix Metalloproteinases and Their Tissue Inhibitors in Blood Serum of Patients with Endometrial Cancer: Clinical and Morphological Correlations.

In patients with endometrial cancer (N=94), endometrial polyps (N=28), endometrial hyperplasia (N=25), and healthy women (N=77), the serum contents of MMP-2, MMP-7, MMP-9, TIMP-1, and TIMP-2 were measured by ELISA. Both carcinoma and benign neoplasms were accompanied by significant elevation of MMP-7 and TIMP-2 in blood serum. The greatest elevation (in comparison with the control) was observed for MMP-7, although serum concentration of this marker was practically identical in patients with carcinoma and benign tumors. In contrast, the levels of MMP-2 and TIMP-1 were lower in cancer patients in comparison with the control; in these patients, the levels of MMP-9 and TIMP-1 were also lower than the corresponding levels in patients with polyps and endometrial hyperplasia. There were no significant correlations between the levels of examined markers with tumor metastasizing, its histological structure, and differentiation degree of endometrial cancer. No differences were observed between examined serological markers in patients with polyps and endometrial hyperplasia of various severities. The examined MMPs and TIMPs cannot be advanced as potential diagnostic markers of endometrial cancer, but they can be used to monitor and prognosticate the disease and to assess effectiveness of the targeted therapy.

Five Hypermethylated MicroRNA Genes as Potential Markers of Ovarian Cancer.

MicroRNA and methylation are important epigenetic mechanisms in the pathogenesis of cancer. The role of a group of microRNA hypermethylated genes in the pathogenesis of ovarian cancer was studied and their diagnostic and prognostic potential was evaluated. Studies on a representative sample of 54 ovarian cancer specimens with the use of methyl-specific PCR resulted in detection of five microRNA genes (MIR-9-1, MIR-9-3, MIR-107, MIR-1258, and MIR-130b) methylated in the majority of tumor specimens in comparison with paired specimens of histologically intact tissue (37-57% vs. 4-9%, p<0.01). Methylation of three genes (MIR-9-1, MIR-9-3, and MIR-130b) was significantly (p≤0.05) associated with the parameters of ovarian cancer progress (clinical stage, differentiation degree, tumor size, and presence of metastases). These findings attest to oncosuppressive role of the studied microRNA genes (MIR-9-1, MIR-9-3, MIR-107, MIR-1258, and MIR-130b) in the pathogenesis and progress of ovarian cancer and indicated their prognostic potential.

[Methylation of the genes for the microRNAs miR-129-2 and miR-9-1, changes in their expression, and activation of their potential target genes in clear cell renal cell carcinoma].

Methylation of promoter CpG islands and microRNA (miRNA) interactions with mRNAs of target genes are epigenetic mechanisms that play a crucial role in deregulation of gene expression and signaling pathways in tumors. Altered expression of six chromosome 3p genes (RARB(2), SEMA3B, RHOA, GPX1, NKIRAS1, and CHL1) and two miRNA genes (MIR-129-2 and MIR-9-1) was observed in primary clear cell renal cell carcinomas (ccRCCs, 31-48 samples) by RT-PCR and qPCR. Significant downregulation (p < 0.05, Fisher's exact test) was observed for SEMA3B, NKIRAS1, and CHL1; and differential expression, for the other chromosome 3p and miRNA genes. Methylation-specific PCR with primers to RARB(2), SEMA3B, MIR-129-2, and MIR-9-1 showed that their methylation frequency was significantly (p < 0.05, Fisher's exact test) elevated in the ccRCC samples. Significant correlations between promoter methylation and expression were confirmed for SEMA3B and observed for the first time for RARB(2), GPX1, and MIR-129-2 in ccRCC (Spearman's correlation coefficient rs ranging 0.31-0.60, p < 0.05). The MIR-129-2 and RARB(2) methylation frequencies significantly correlated with ccRCC progression. MIR-129-2 methylation correlated with upregulation of RARB(2), RHOA, NKIRAS1, and CHL1 (rs ranging 0.35-0.53, p < 0.05). The findings implicate methylation in regulating RARB(2), SEMA3B, GPX1, and MIR-129-2 and indicate that miR-129-2 and methylation of its gene affect RARB(2), RHOA, NKIRAS1, and CHL1 expression.

Loss of Cell Differentiation in HPV-Associated Bladder Cancer.

Medical histories of 101 urothelial bladder cancer patients were compared with the results of morphological analysis and biomolecular detection of human papilloma viruses (HPV) in the tumor specimens. DNA of HPV16 (the major type of virus responsible for appearance of cervical carcinoma) was detected in 38 specimens, while mRNA of E6 and E7 oncogenes and E7 oncoprotein of HPV16 were observed in 13 specimens. HPV-positive bladder cancer was characterized by higher degree of cell anaplasia than HPV-negative cancer; in the primary bladder tumor, HPV was detected more often than in recurrent bladder cancer. These data attest to involvement of HPV16 in the genesis of bladder cancer. No correlations of HPV status of bladder tumor with patient's sex, age, and invasion into the muscle layer were revealed.

Insulin-Like Growth Factors (IGF) and IGF-Binding Proteins (IGFBP) in the Serum of Patients with Ovarian Tumors.

IGF-1, IGF-2, and IGFBP-1,2,3 were assayed in blood serum of patients with malignant ovarian tumors (n=44), borderline ovarian tumors (n=11), and benign ovarian tumors (n=12) as well as in healthy women (n=33). In blood serum of patients with malignant ovarian tumors, the level of IGF-1 was lower and IGFBP-1 was higher than in other groups. In patients with malignant and borderline ovarian tumors, the level of IGFBP-2 was higher than in healthy women and in patients with benign ovarian tumors. There was no correlation between most examined parameters and the clinical and morphological peculiarities of ovarian tumors. The study revealed IGF/IGFBP imbalance in patients with malignant ovarian tumor and showed that IGFBP-2 proved to be a potential diagnostic serological marker w with 90% sensitivity and 90% specificity.

Regulatory Proteins of Epithelial-Mesenchymal Transition and Some Components of VEGF Signaling Pathway in Breast Cancer.

Immunohistochemical method was used to assay for Snail family regulatory proteins of epithelial-mesenchymal transition, their NF-κB coactivator, and the components of VEGF signaling pathway (VEGF and its receptors VEGFR1 and VEGFR2) in 157 specimens of breast tumors. Most tumors did not express SNAI1, while 65% tumors demonstrated mid- or high-level SNAI2 expression. There were significant correlations between the expression of SNAI1, SNAI2, and their NF-κB co-activator. Correlation was also detected between expression of Snail and VEGFR1 protein families in the tumors. In addition, the study revealed tumoral co-expression of SNAI2 and VEGFR2. The data attest to coordinated activation of regulatory proteins of epithelial-mesenchymal transition and the major components of VEGF signaling pathway in breast tumors.

Complex of molecular genetic and immunohistochemical methods for detection of human papillomavirus in the bladder cancer epithelium.

A battery of tests for detection human papillomavirus DNA, mRNA corresponding to viral oncogenes, and viral oncoprotein E7 in cancer bladder urothelium was piloted in 35 samples of bladder cancer. DNA of human papillomavirus type 16 (causes cervical cancer) was found in 16 (46%) samples; E6/E7 oncogene transcript and E7 oncoprotein of human papillomavirus type 16 were detected in 10 and 7 human papillomavirus DNA-positive samples, respectively. These findings attest to association of bladder cancer with human papillomavirus in Russia.

[Methylation profile of group of miRNA genes in clear cell renal cell carcinoma; involvement in cancer progression].

MicroRNA regulates gene expression, is involved in many cellular processes, and plays an important role in the development of cancer. The regulation of the expression of miRNA genes can be achieved by methylating their CpG islands, which is shown in different types of tumors. The methylation of miRNA genes in clear cell renal cell carcinoma (CCRCC) has mainly been studied for the miR-9 and miR-34 families. The methylation of six miRNA genes (miR-124a-2, -124a-3, -9-1, -9-3, -34b/c, -129-2) was investigated with the use of representative set of CCRCC samples (46 cases). Methylation of three genes miR-124a-2, -124a-3, and -129-2 was studied in kidney tumors for the first time. Methylation analysis was performed using methyl specific PCR. It is shown that the frequency of methylation of six genes (miR-124a-2, -124a-3, -9-1, -9-3, -34b/c and -129-2) was significantly higher in tumor samples than in samples of histologically normal tissue (P < 3 x 10(-5) by Fisher's exact test). These results suggest the properties of tumor suppressors for the six miRNA genes indicated in CCRCC. We also found correlations between the methylation frequency of some miRNA genes and signs of the progression of CCRCC (tumor size, clinical stage, loss of differentiation, and metastasis).

Actin isoforms and reorganization of adhesion junctions in epithelial-to-mesenchymal transition of cervical carcinoma cells.

Malignant cell transformation requires changes in the ability of cells to migrate. The disruption of actin cytoskeleton and intercellular adhesions is an important component of the acquisition of invasive properties in epithelial malignancies. The invasive ability of carcinoma cells is associated with reduced expression of adhesion junction molecules and increased expression of mesenchymal markers, frequently referred to as epithelial-to-mesenchymal transition (EMT). Standard features of the EMT program in cancer cells include fibroblastic phenotype, downregulation of the epithelial marker E-cadherin, induction of Snail-family transcription factors, as well as expression of mesenchymal proteins. We compared the epithelial and mesenchymal marker profiles of nonmalignant HaCaT keratinocytes to the corresponding profiles of cervical carcinoma cell lines C-33A, SiHa, and CaSki. The characteristics of the EMT appeared to be more developed in SiHa and CaSki cervical cancer cells. Further activation of the EMT program in cancer cells was induced by epidermal growth factor. Decreased epithelial marker E-cadherin in CaSki cells was accompanied by increased mesenchymal markers N-cadherin and vimentin. Downregulated expression of E-cadherin in SiHa and CaSki cells was associated with increased expression of Snail transcription factor. Our goal was to study actin reorganization in the EMT process in cell cultures and in tissue. We found that ß-cytoplasmic actin structures are disorganized in the cervical cancer cells. The expression of ß-cytoplasmic actin was downregulated.

[pAkt expression in cervical intraepithelial neoplasia (CIN) and in microinvasive cervical cancer].

The study objective was an immunohistochemical evaluation of pAkt expression in 81 CIN and microinvasive cervical cancer tissue samples and 10 samples of relatively "normal" cervical epithelium of HPV-infected women. PAkt expression showed significant up-regulation in CIN2, CIN3 and microinvasive cancer in compare to CIN1 and "normal" epithelium. The rate of pAkt- positive cells increased progressively by cervical neoplasia grade advancement reaching 7 +/- 5% in CIN2, 15 +/- 13% in CIN3 and 17 +/- 15% in microinvasive cancer. The rate of pAkt-positive cases in general was 1,7-fold higher in CIN3 (41%) than in CIN2 (24%). pAkt expression in conjunction with other markers may be used in immunohistochemical studies for individual CIN outcome prognosis and prospectively in immunocytochemical tests for CIN grade diagnostics improvement before using invasive methods. To elaborate multicomponent system of markers with their indexation there is a need for further investigations with greater number of cases.

[Ki-67 expression, thymidine phosphorylase and PTEN in intraepithelial cervical carcinoma].

Expression of Ki-67, thymidine phosphorylase (TP) and PTEN were assessed in various grades of cervical intraepithelial neoplasia (CIN) in order to evaluate their potentials of predicting the gravity of possible damage to the epithelium as well as pro- or regression of CIN. Ki-67 and TP levels were shown to correlate directly with CIN grade. It was suggested that a small number of cases of Ki-67 and TP expression absence (15%), exclusively in CIN3 samples, be due to imminent progression to invasive cancer. Both separately and in combination, Ki-67 and TP expression indices should be regarded as having a potential as markers for cervical carcinoma diagnosis, grade and clinical course.

Matrix metalloproteinases 2, 7, and 9 in tumors and sera of patients with breast cancer.

Enzyme immunoassay showed that the content of matrix metalloproteinases (MMP) 2 and 7 in tumors was higher than in the adjacent histologically intact tissue in 91 and 76% patients with breast cancer, respectively, while MMP-9 levels in the tumor and intact tissue were virtually the same. Serum concentrations of MMP-2 and MMP-7 did not correlate with their levels in the tumors, were within the normal range, and virtually did not decrease after removal of the primary tumor. Serum levels of MMP-9 in patients were significantly lower than in the control and increased after surgery in 85% patients. No clear-cut relationship between the studied parameters and clinical morphological prognostic factors of breast cancer was detected.

[The role of cervical transformational zone as an object of human papilloma virus oncogenic effect in cervical intraepithelial neoplasms and invasive cancer development].

The correlation of morphological mistakes in neoplasia grade verification from visibility of transformation zone (TZ) and patient age was studied in 503 patients with CIN and microinvasive cervical cancer. The square of ectocervix lesion was defined by LeiseCap software in colposcopic working station Leisegang 3MV. The exclusive significance of TZ in HPV-associated cancerogenesis was confirmed clinically. We've established that the neoplasia stage increases with age while lesion extension and TZ visibility decrease dramatically leading to the subsequent decrease in colposcopy sensitivity and adequacy of guided biopsy. The critical age for underdiagnosis of latent lesions seems to be 35 years. The diagnostic and therapeutic value of conization and the large loop excision of the TZ (LLETZ) as the procedures with the optimal TZ excision in patients with visibly unchanged ectocervix are confirmed in cases when CIN 2-3 and microinvasive cancer are suspected.

Cellular expression of INK4a gene in cells of bladder cancer associated with human papilloma virus-16.

Hyperexpression of p16(INK4a) protein is an early marker of cervical cancer. Hyperexpression of INK4a gene encoding this protein at the level of mRNA and p16(INK4a) was detected in tumor cells of some patients with bladder cancer associated with human papilloma virus-16. However, in contrast to cervical cancer, this phenomenon in urothelial carcinomas does not correlate with expression of human papilloma virus-16 oncogenes E6 and E7.

[Are human papillomaviruses responsible for the occurrence of bladder cancer].

A female patient with recurrent bladder cancer underwent complex examination. The primary tumor removed in 2004 showed human papillomavirus (HPV) 16 DNA, mRNA corresponding to HPV16 oncogene E7, as well as HPV16 protein E7. The patient is a smoker who has been working at a chemical factory for over 20 years. During tumor recurrence in 2009, there was no DNA of high-risk HPV types in the cancer cells. HPV16 E7protein and cellular p 16(INK4alpha), an indicator of HPV-induced carcinogenesis, were not found. Colposcopy revealed no precancerous changes in the epithelium of the cervix uteri. The cervical epitheliocytes contained no high-risk HPV DNA, E7 and p16(INK4alpha) proteins. It seems expedient to continue in vitro studies of the possible role of HPV in urothelial carcinogenesis on an experimental model.

[Actins and keratins in the diagnosis of human basal-like breast cancer].

The most common forms of luminal breast cancer (BC) were compared with basal-like and Her2/neu3+ BC. Their primary classification was based on morphological diagnosis and the expression of estrogen receptor (ER), progesterone receptor (PR), and Her2/neu receptors. Monoclonal antibodies to actins and keratins were used for the study. Basal-like BC cells (ER/PR/Her2/ neu-) were regularly stained with antibodies to basal keratins 5/6 and 17, smooth muscle alpha-actin, and p63. Luminal keratin 8 staining was reduced. The solid regions had beta-actin staining with disappearance in the scirrhous component. beta-actin and basal keratins were also observed in metaplastic BC with ER/PR/Her2/neu3+. Immunomorphology using cytoskeletal markers along with the expression of steroid hormone and Her2/neu receptors may be used in the diagnosis of basal-like forms of BC.

[Detection of oncoprotein E7 HPV16 in the cancer and normal urinary bladder urothelium].

Oncoprotein E7 HPV16 was detected by immunohistochemical staining with specific polyclonal antiserum [Fiedler et al., 2004] in 7 out of the 24 (29.2%) studied bladder cancer specimens. The result is in good agreement with the hypothesis that HPVs take part in the carcinogenesis of the urothelium. However, some of the observations made seem rather hard to be interpreted at present. The latter include the detection of E7 HPV16 in a small number of cancer cells in a few bladder cancer specimens being examined; the presence of this protein in the cytoplasm, rather in the cancer cell nuclei, and its detection in some morphologically normal bladder urothelial specimens from non-cancer patients. Thus, the hypothesis that HPVs are implicated in the carcinogenesis of the bladder urothelium deserves further verification.

[Methylation of promoter region of RASSF1A gene and frequencies of allelic imbalances in chromosome 3 critical regions are correlated with progression of clear cell renal cell carcinoma].

The short arm of chromosome 3 (3p) contains several critical regions harboring the set of genes with tumor suppressor activities. The RASSF1A gene (LUCA region, 3p21.31) shows various functions which can be associated with tumorigenesis. Among 3p genes this gene can be most frequently methylated in epithelial tumors of various locations. Here two independent methods (methyl-specific PCR and methyl-sensitive restriction analysis) were used to show significant correlation of methylation level of promoter region of this gene with grade and clinical stage of clear cell renal cell carcinoma (RCC) for the first time. Analysis of 23 polymorphic markers of 3p using the representative set of samples (80 cases RCC), described clinically and histological, permitted to reveal significant correlation between frequency of allelic alterations in some critical regions of 3p (LUCA and AP20) and RCC progression, as distinct from the whole 3p. These data suggest that methylation of promoter region of the RASSF1A gene is associated with RCC progression, and besides, structure-functional alterations in other 3p genes can be also related with RCC progression. In addition, significant correlation between RASSF1A methylation events and allelic losses in the close polymorphic marker was shown here, pointing to the role of "two hit" model for this tumor-suppressor gene inactivation in RCC.