Soluble B7-H3 in Colorectal Cancer.

We present the results of comparative ELISA of the concentration of soluble form of immunity checkpoint B7-H3 (sB7-H3) in the serum of patients with colorectal cancer (CRC) at different stages before treatment and healthy control donors. The analysis revealed a statistically significant difference between the median levels of sB7-H3 in the blood serum of CRC patients (19.66 ng/ml) and healthy donors (16.76 ng/ml) (p=0.0025). ROC analysis showed 62.9% sensitivity and 56.7% specificity for CRC patients (cut-off 17.62 ng/ml; p=0.0028). An association of sB7-H3 levels with tumor progression was revealed. We demonstrated that sB7-H3 levels were significantly lower in patients with regional metastases than in patients without metastases (p=0.039) and that sB7-H3 concentration tends to decrease at the late stages of the disease. Thus, high serum level of sB7-H3 in CRC patients can be a favorable prognostic factor in future.

[Landscape of KRAS, BRAF, and PIK3CA Mutations and Clinical Features of EBV-Associated and Microsatellite Unstable Gastric Cancer].

Personalization of gastric cancer (GC) treatment is an urgent problem because of the clinical heterogeneity and aggressive course of the disease. Four GC subtypes were isolated based on molecular characteristics by The Cancer Genome Atlas researchers in 2014: Epstein-Barr virus positive (EBV^(+)), microsatellite unstable (MSI), chromosomally unstable (CIN), and genomically stable (GS). There is no unified method to detect the CIN and GS subtypes today, while MSI and EBV status assessments are used routinely and are of great clinical importance. A total of 159 GC samples were tested for MSI, EBV DNA, and somatic mutations in codons 12-13 (exon 2), 61 (exon 3), and 146 (exon 4) of the KRAS gene; codons 597-601 (exon 15) of the BRAF gene; and codons 542-546 (exon 9), 1047-1049 (exon 20) of the PIK3CA gene. EBV^(+) GC was detected in 8.2% of samples; and MSI, in 13.2%. MSI and EBV+ were found to be mutually exclusive. The mean ages at GC manifestation were 54.8 and 62.1 years in patients with EBV^(+) and MSI GCs, respectively. EBV^(+) GC affected men in 92.3% of cases, 76.2% of the patients were older than 50 years of age. Diffuse and intestinal adenocarcinomas were diagnosed in 6 (46.2%) and 5 (38.5%) EBV^(+) cases, respectively. MSI GC equally affected men (n = 10, 47.6%) and women (n = 11, 52.4%). The intestinal histological type was the most prevalent (71.4%); the lesser curvature was affected in 28.6% of the cases. The E545K variant of PIK3CA was observed in one EBV^(+) GC case. A combination of clinically significant variants of KRAS and PIK3CA was found in all MSI cases. The BRAF V600E mutation, which is specific to MSI colorectal cancer, was not detected. The EBV^(+) subtype was associated with better prognosis. The five-year survival rates were 100.0 and 54.7% for MSI and EBV^(+) GCs, respectively.

Computer-aided Evaluation of Polyvalent Medications' Pharmacological Potential. Multiphytoadaptogen as a Case Study.

Many human diseases including cancer, degenerative and autoimmune disorders, diabetes and others are multifactorial. Pharmaceutical agents acting on a single target do not provide their efficient curation. Multitargeted drugs exhibiting pleiotropic pharmacological effects have certain advantages due to the normalization of the complex pathological processes of different etiology. Extracts of medicinal plants (EMP) containing multiple phytocomponents are widely used in traditional medicines for multifactorial disorders' treatment. Experimental studies of pharmacological potential for multicomponent compositions are quite expensive and time-consuming. In silico evaluation of EMP the pharmacological potential may provide the basis for selecting the most promising directions of testing and for identifying potential additive/synergistic effects. Multiphytoadaptogen (MPhA) containing 70 major phytocomponents of different chemical classes from 40 medicinal plant extracts has been studied in vitro, in vivo and in clinical researches. Antiproliferative and anti-tumor activities have been shown against some tumors as well as evidence-based therapeutic effects against age-related pathologies. In addition, the neuroprotective, antioxidant, antimutagenic, radioprotective, and immunomodulatory effects of MPhA were confirmed. Analysis of the PASS profiles of the biological activity of MPhA phytocomponents showed that most of the predicted anti-tumor and anti-metastatic effects were consistent with the results of laboratory and clinical studies. Antimutagenic, immunomodulatory, radioprotective, neuroprotective and anti-Parkinsonian effects were also predicted for most of the phytocomponents. Effects associated with positive effects on the male and female reproductive systems have been identified too. Thus, PASS and PharmaExpert can be used to evaluate the pharmacological potential of complex pharmaceutical compositions containing natural products.

Diagnostic and prognostic potential of the resident non-small cell lung cancer microbiome.

The data of a comprehensive comparative study of the taxonomic composition of the resident microbiome of tumors from 26 patients with non-small cell lung cancer are presented. Analysis of taxonomic diversity revealed 10 types, 280 genera and 788 species of microorganisms. The analysis of the relative content and prognostic significance was carried out for 62 dominant genera. Differences in the relative abundance of bacteria of the genera Acinetobacter, Halomonas, and Chryseobacterium between tumor and conditionally normal lung tissue were found, but their diagnostic potential was not confirmed. The correlation analysis did not reveal any relationship between the content of various genera of bacteria and the histological type of the tumor, its localization, and the age of the patients. Differences were found in the content of the studied bacteria depending on the stage of the disease, the presence of regional metastases and tumor differentiation. The prognostic significance of bacteria of the genera Variovorax and Pseudoclavibacter in non-small cell lung cancer was established. The results obtained can be used in the development of new effective methods for the diagnosis and prognosis of non-small cell lung cancer.

Blood Serum Zonulin in Colorectal Cancer, Autoimmune Bowel Diseases, and Irritable Bowel Syndrome.

Zonulin content in blood serum of patients with colorectal cancer (CRC; n=152; 30-84 years) and patients with large bowel adenomas (n=32; 39-82 years) was measured by standardized kit IDK Zonulin ELISA (Immundiagnostik AG). The healthy control group (n=50) comprised volunteers (27 women, 23 men; 25-68 years); pathological control group (n=84) - patients (55 women, 29 men;18-84 years) with irritable bowel syndrome (n=29), Crohn's disease (n=5), and ulcero-necrotic colitis (n=50). In comparison to healthy control group, the level of zonulin was significantly increased in CRC patients (p<0.0000001) and in patients with benign large bowel tumors (p<0.004), as well as in patients with inflammatory intestine diseases and with irritable bowel syndrome (p<0.0002). Zonulin level in blood serum of CRC patients was slightly, but significantly higher (p<0.05) than in the group of pathological control. ROC curve construction revealed that at optimal zonulin cut-off level (52.2 ng/ml), the diagnostic sensitivity of CRC detection was 66.7% and specificity relative to healthy control was 81.8%. The specificity relative to the combined control group (healthy control+non-tumor bowel diseases) was only 68.9%. Thus, no acceptable cut-off levels for differentiation between malignant and benign tumors, as well as between tumor and non-tumor large bowel pathologies were found. Analysis of the associations between serum zonulin level and the main clinical and pathological characteristics of CRC demonstrated that the level of this marker increased with disease progression (p<0.01; Kruskal-Wallis test), but was not associated with individual criteria of the TNM system, tumor localization, histological structure, and malignancy grade.

[Gastric cancer complicated by bleeding. (A systematic review)]. / Rak zheludka, oslozhnennyi krovotecheniem. (Sistematicheskii obzor literatury).

Bleeding as the most common complication of gastric cancer is a significant problem of modern surgery. Both oncologists and surgeons in ordinary hospitals deal with this adverse event. In addition to the well-known drugs for hemostasis, there are also generally recognized traditional methods of endoscopic hemostasis and transcatheter angiographic embolization. Surgical interventions do not lose their role too if previous hemostatic methods turned out to be ineffective. The reports devoted to radiotherapy for treatment and prevention of gastric bleeding following malignant process have been recently published. Such a wide choice of hemostatic methods prompted us to analyze the most significant recent studies regarding effectiveness of various methods and choice of the most optimal one.

The Level of LINE-1 mRNA Is Increased in Extracellular Circulating Plasma RNA in Patients with Colorectal Cancer.

We performed a comparative quantitative analysis of LINE-1 mRNA levels in extracellular total plasma RNA in patients with colon cancer and practically healthy donors. Quantitative multiplex PCR with reverse transcription was used to assess the level of LINE-1 and 18S rRNA mRNA in extracellular total plasma RNA. The median of LINE-1 mRNA values in colon cancer patients (4.95) was significantly higher than in healthy donors (2.3) (p=0.037). It was shown for the first time that the level of LINE-1 mRNA in total RNA from blood plasma can be determined in the format of a liquid biopsy and serve as a new potential non-invasive marker of colon cancer.

Pro-Gastrin-Releasing Peptide as a Marker of Small Cell Lung Cancer.

The serum levels of pro-gastrin-releasing peptide (proGRP), neuron-specific enolase (NSE), and chromogranin A (CgA) were studied in 69 patients with small cell lung cancer and 50 apparently healthy donors. A significant increase of all studied biochemical markers was revealed in small cell lung cancer patients, while the highest diagnostic efficiency was demonstrated by proGRP compared to NSE and CgA. ProGRP is a promising biochemical marker of small cell lung cancer, especially sensitive in patients with distant metastases (in the brain, liver, and bones).

[Gastric cancer complicated by bleeding: a systematic review]. / Rak zheludka, oslozhnennyi krovotecheniem.

Bleeding as the most common complication of gastric cancer is a significant problem of modern surgery. Both oncologists and surgeons in ordinary hospitals deal with this adverse event. In addition to the well-known drugs for hemostasis, there are also generally recognized traditional methods of endoscopic hemostasis and transcatheter angiographic embolization. Surgical interventions do not lose their role too if previous hemostatic methods turned out to be ineffective. The reports devoted to radiotherapy for treatment and prevention of gastric bleeding following malignant process have been recently published. Such a wide choice of hemostatic methods prompted us to analyze the most significant recent studies regarding effectiveness of various methods and choice of the most optimal one.

Comprehensive Analysis of Stromal and Serum Markers in Gastric Cancer.

A comprehensive analysis of the cell phenotype of the inflammatory infiltrate of the tumor stroma represents a promising area of molecular oncology. The study of not only soluble forms of various immunoregulatory molecules, but also their membrane-bound forms is also considered highly relevant. We performed a comprehensive analysis of tissue and circulating forms of the PD-1 and PD-L1 proteins, as well as macrophage and B-cell markers in the tumor stroma of gastric cancer, to assess their clinical and prognostic significance. The tumor and blood plasma samples from 63 gastric cancer patients were studied using ELISA and immunohistochemistry. Malignant gastric tumors were shown to be strongly infiltrated by B-cells, and their number was comparable to that of macrophages. For PU.1 expression, an association with tumor size was observed; i.e., larger tumors were characterized by fewer PU.1+ infiltrating cells (p = 0.005). No clinical significance was found for CD20 and CD163, but their numbers were higher at earlier stages of the disease and in the absence of metastases. It was also demonstrated that the PD-L1 content in tumor cells was not associated with the clinical and morphological characteristics of GC. At the same time, PD-L1 expression in tumor stromal cells was associated with the presence of distant metastases. The analysis of the prognostic significance of all the markers studied demonstrated that CD163 was statistically significantly associated with a poor prognosis for the disease (p = 0.019). In addition, PD-L1 expression in tumor cells tended to indicate a favorable prognosis (p = 0.122). The results obtained in this work indicate that the study of soluble and tissue markers of tumor stroma is promising in prognosticating the course of GC. The search for combinations of markers seems to be highly promising, with their comprehensive analysis capable of helping personalize advanced antitumor therapy.

Prognostic significance of VEGF signaling system components and matrix metalloproteinases in blood serum of gastric cancer patients.

Analysis of long-term treatment results of 77 primary gastric cancer patients at stage I-IV of the tumor process followed during 1 - 41 months (median - 6.4 months) from the onset of specific treatment are presented depending on the basal levels of VEGF, soluble forms of its receptors (sVEGFR1, sVEGFR2) and matrix metalloproteinases (MMP-2, 7, 9) in blood serum. Overall survival assessed by Kaplan-Meyer analysis and with the help of Cox multiparametric regression model was applied as the criterion of prognostic value. It was found that at high (≥ 420 pg/ml) serum VEGF, the overall survival of patients with gastric cancer was statistically significantly lower than at the marker's levels below 420 pg/ml (p<0.011): 3-year's survival comprised 46,3±12,5% and 88,2±7,8% respectively. Median survival of patients with high VEGF level comprised 21.7 months, of those with low VEGF was not achieved during the whole follow-up period. Serum sVEGFR1, sVEGFR2, MMP-2, 7 and 9 levels were not significantly associated with the overall survival of patients included in this study. Only index M of TNM system and serum VEGF level demonstrated an independent prognostic value in multiparametric model (p=0.036). Thus, it was confirmed that VEGF signaling pathway plays an important role in gastric cancer, and its components - in the first place, VEGF A - are substantial factors of disease prognosis, and can also be useful for monitoring of treatment efficiency.

[Active surgical approach for retroperitoneal liposarcoma]. / Rol' aktivnoi khirurgicheskoi taktiki pri zabryushinnoi liposarkome.

OBJECTIVE: To assess the influence of active surgical approach on the long-term postoperative outcomes in patients with retroperitoneal liposarcoma. MATERIAL AND METHODS: A retrospective study included 190 patients with retroperitoneal liposarcoma. The effect of malignancy grade, adjuvant chemotherapy, number of separate tumor nodes in primary neoplasm and the first relapse, as well as the number of previous total resections on survival rate was analyzed. RESULTS: Overall and relapse-free survival is significantly worse in patients with high-grade retroperitoneal liposarcoma (G2-3) compared to low-grade (G1) tumor (plog-rank=0.000). Multifocal growth of primary tumor (p=0.869; plog-rank=0.607) and multiple (>1) separately located nodes in abdominal cavity and retroperitoneal space at the first relapse (plog-rank=0.158 to 0.985) did not significantly impair prognosis after total resection of all types of retroperitoneal liposarcoma regardless malignancy grade. Adjuvant chemotherapy does not significantly improve relapse-free survival. Overall survival was significantly higher in patients who underwent ≥4 previous total resections compared to 1 surgical treatment for all types of retroperitoneal liposarcoma regardless malignancy grade (p=0.000; plog-rank=0.001). CONCLUSION: The only potentially radical treatment for patients with retroperitoneal liposarcoma is surgery. We reported the advantages of active surgical approach for improvement of long-term outcomes in patients with retroperitoneal liposarcoma.

[Surgical and combined treatment of patients with duodenal stromal tumors]. / Osobennosti khirurgicheskogo i kombinirovannogo lecheniya bol'nykh stromal'noi opukhol'yu dvenadtsatiperstnoi kishki.

OBJECTIVE: To evaluate the immediate and long-term results of surgical and combined treatment of patients with duodenal stromal tumors. MATERIAL AND METHODS: There were 47 patients with duodenal stromal tumors for the period 2002-2019. All patients underwent treatment at the Blokhin National Cancer Research Center. Six patients had metastatic disease, 2 ones - a rare syndrome of duodenal stromal tumor associated with neurofibromatosis type 1, other 39 patients had a localized and locally-advanced disease. Surgical treatment was performed in 37 patients (limited resections (LR) in 24 cases and gastropancreaticoduodenectomy in 13 cases).Incidence of postoperative complications was significantly lower after limited resections compared to gastropancreaticoduodenectomy (22.2% (6/24) vs. 61.5% (8/13), respectively). Severe complications (Clavien-Dindo grade 3) occurred in 4.2% (1/24) vs. 15.3% (2/13) of patients, respectively. Postoperative mortality was absent in both groups. We observed no significant differences in long-term results. Overall 5-year survival was 91% and 70% (p=0.5960), 5-year recurrence-free survival - 65 and 70% (p=0.6226), respectively. CONCLUSION: Considering similar survival rates, lower postoperative morbidity and better quality of life, limited duodenal resections are preferred for duodenal stromal tumors.

[Gastrointestinal stromal duodenal tumors: diagnostic mistakes and modern approaches to treatment]. / Gastrointestinal'nye stromal'nye opukholi dvenadtsatiperstnoi kishki: oshibki diagnostiki i sovremennye podkhody k lecheniyu.

Gastrointestinal stromal duodenal tumors are rare diseases of small intestine. Duodenal GISTs may be giant; these neoplasms can also simulate malignancies of other organs. These features result diagnostic and treatment mistakes. Neoadjuvant therapy with imatinib results tumor shrinkage and ensures organ-sparing surgery. We report duodenal GISTs in patients with primary diagnosis «retroperitoneal tumor¼, «pancreatic cyst¼ and «retroperitoneal abscess¼, who were treated at the Blokhin National Cancer Research Centre in 2019-2020.

[Differentiated surgical approach for retroperitoneal non-organ liposarcoma]. / Differentsirovannyi podkhod v khirurgii zabryushinnykh neorgannykh liposarkom.

OBJECTIVE: To determine the indications for combined and organ-sparing surgery depending on malignancy grade of retroperitoneal liposarcoma. MATERIAL AND METHODS: A retrospective study included 190 patients with retroperitoneal liposarcoma. Influence of malignancy grade, lesion of adjacent organs and resection/excision of adjacent organs on the overall and recurrence-free survival was studied. Moreover, we analyzed the issue of kidney-sparing surgery and nephrectomy. RESULTS: Overall and recurrence-free survival were significantly worse in high grade (G2-3) compared to low-grade tumors (G1) (p=0.0001; log-rank test). Visceral invasion was revealed in 23% of patients with low-grade (G1) tumors and 53% of patients with high-grade (G2-3) neoplasms. Visceral invasion significantly impairs overall and recurrence-free survival in both low grade (G1) and high-grade (G2-3) tumors (p=0.0001; log-rank test). In case of low grade (G1) retroperitoneal liposarcoma, overall and recurrence-free survival was similar after combined surgery without histologically confirmed visceral invasion of liposarcoma and organ-sparing surgery (p=0.006; p=0.053; log-rank test). On the contrary, high grade (G2-3) tumor was followed by significantly better overall and recurrence-free survival after combined surgery without histologically confirmed visceral invasion compared to organ-sparing surgery (p=0.006; p=0.053; log-rank test). Recurrence-free survival was similar after kidney-sparing surgery and nephrectomy among patients with low-grade (G1) tumor (p=0.456; log-rank test). In case of high-grade retroperitoneal liposarcoma (G2-3), recurrence-free survival was significantly worse after kidney-sparing surgery compared to nephrectomy (p=0.039; log-rank test). CONCLUSION: Surgery is the only potentially radical treatment of patients with retroperitoneal liposarcoma. Organ-sparing including kidney-sparing surgery is advisable for low-grade liposarcoma (G1). On the contrary, organ-sparing surgery impairs long-term results and prognosis in patients with high-grade tumors (G2-3). Combined operations including nephrectomy are justified for high-grade retroperitoneal liposarcoma (G2-3).

[Possibilities of in silico estimations for the development of pharmaceutical composition phytoladaptogene cytotoxic for bladder cancer cells]. / Vozmozhnosti otsenok in silico dlia razrabotki farmkompozitsii fitoladaptogen, tsitotoksichnoi dlia kletok raka mochevogo puzyria.

Based on the prediction of biological activity spectra for several secondary metabolites of medicinal plants using the PASS computer program and validation in vitro of the predictions results the priority direction of the pharmaceutical composition Phytoladaptogene (PLA) development was determined. PLA is a complex of structurally diverse small organic compounds including biologically active substances of phytoadaptogenes (ginsenosides from Panax ginseng, rhodionin from Rhodiola rosea and others) compiled considering previously developed pharmaceutical compositions. Two variants of the pharmaceutical composition were studied: - the major and minor variants included 22 and 13 compounds, respectively. The probability of activity exceeds the probability of inactivity for 1400 out of 1945 pharmacological effects and mechanisms predicted by PASS for the major variant of PLA. The wide range of predicted activities is mainly due to the low structural similarity of constituent compounds. An in silico prediction indicates the possibilities of antitumor properties against bladder, stomach, colon, ovarian and cervical cancers both for minor and major PLA compositions. It was found that the highest probability values of activity were predicted for three mechanisms: apoptosis agonist, caspase-3 stimulant, and transcription factor NF-κB inhibitor. According to the PharmaExpert program they are associated with the antitumor effect against bladder cancer. Experimental validation was using the human bladder cancer cell line RT-112. The results of the MTT test have shown that the cytotoxicity of the major PLA variant is higher than that of the minor PLA variant. In vitro experiments performed using two methods (double staining with annexin V and propidium iodide and detection of active caspase-3 in cells) confirmed that the death of bladder cancer cells occurred via the apoptotic mechanism. The data obtained correspond to the results of the prediction and indicate advantages of the major PLA composition. Thus, PLA can become the basis for the development of a drug with the antitumor activity against bladder cancer. The antitumor activity predicted by PASS for other cancers may be the subject of further studies.

Prognostic significance of soluble forms of immune checkpoint PD-1/PDL1 receptor and ligand in blood plasma of gastric cancer patients.

Analysis of long-term treatment results of 101 primary gastric cancer patients at various stages of the tumor process followed during 1 - 41 months (median - 6,4 months) from the onset of specific treatment are presented depending on the levels of soluble forms (s) of PD-1 receptor and its ligand PD-L1 in blood plasma. Overall survival assessed by Kaplan-Meyer analysis and with the help of Cox multiparametric regression model was applied as the criterion of prognostic value. It was found that at high (≥ 35 pg/ml) sPD-L1 levels in blood plasma, the overall survival of patients with gastric cancer was statistically significantly lower than at the marker's levels below 35 pg / ml (p <0.045): 1-year survival comprised 78 and 96%, 2-year - 52 and 78%; 3-year - 40 and 61% at high and low sPD-L1 respectively. Median survival of patients with high plasma sPD-L1 comprised 29 months, of those with low sPD-L1 was not achieved during the whole follow-up period. This trend was observed not only in the total group of stage I-IV gastric cancer patients, but also in patients at the early stages of the disease, though sPD-L1 did not show an independent prognostic value in multiparametric model. At the same time, the overall survival of patients with gastric cancer did not depend on the baseline levels sPD-1 in blood plasma. Thus, soluble ligand sPD-L1 can be considered as a potentially valuable factor for prognosis of gastric cancer patients' survival, and, probably, of anti-PD-1/PD-L1 treatment efficiency, but further studies and patients' monitoring are required to prove this statement.

Vascular Endothelial Growth Factor and Soluble Forms of Its Receptors 1 and 2 in Gastric Cancer.

Comparative evaluation of blood content of VEGF, sVEGFR1, and sVEGFR2 in 104 primary gastric cancer patients and 65 healthy persons was performed and associations of these markers with the principal clinical and morphological characteristics of gastric cancer were analyzed. The median levels of VEGF and sVEGFR1 in gastric cancer patients significantly surpassed the control: by 1.5 (p<0.001) and 1.2 times (p<0.01), respectively. On the contrary, sVEGFR2 level in patients was below the control (p<0.001). The best sensitivity-specificity ratio (64 and 65%, respectively) was observed for VEGF at 347 pg/ml cut-off value, which is insufficient for the use of this parameter as a clinically valuable serological marker for gastric cancer. No significant associations of these markers with the disease stage, depth of primary tumor invasion, its histological type, grade, or localization were found. The serum level of VEGF in patients with metastases to more than 7 regional lymph nodes (N3) was significantly higher than in patients without lymph node metastases (N0). Blood content of sVEGFR1 in patients with distant metastases (М+) was lower than in patients without distant metastases (М0). Thus, VEGF and its receptors circulating in the peripheral blood do not play significant diagnostic role in gastric cancer, but could be useful in monitoring and prognosis of the efficiency of antiangiogenic therapy.

[Retroperitoneal dedifferentiated liposarcomas: semi-quantitative assessment of the dedifferentiated component and prognosis]. / Zabryushinnye dedifferentsirovannye liposarkomy: polukolichestvennaya otsenka dedifferentsirovannogo komponenta i prognoz.

OBJECTIVE: To evaluate the impact of malignancy grade and the proportion of the dedifferentiated component (DC) in retroperitoneal dedifferentiated liposarcomas (DDLS) on the course and prognosis of the disease. MATERIAL AND METHODS: The retrospective study enrolled 74 patients with primary retroperitoneal DDLS who underwent radical surgical treatment in the N.N. Blokhin National Medical Research Center of Oncology, Ministry of Health of Russia. Histological surgery specimens from all cases of DDLS were reexamined and reclassified. According to malignancy grades and the proportion of the dedifferentiated component in the tumor, the patients were divided into the comparison groups included in the intergroup analysis of overall and relapse-free survival (OS and RFS) rates. The authors also analyzed the relationship between the proportion of the dedifferentiated component in DDLS and the frequency of adjacent organ invasion. RESULTS: Patients with a more than 15% dedifferentiated component had significantly lower OS rates than those with a less than 15% one (p=0.0001; log-rank test). The median OS in the DDLS group with a less than 15% dedifferentiated component was 91 months (95% CI, 82-100); that in the DDLS group with a more than 15% dedifferentiated component was 29 months (95% CI 17-41). The 5-year overall survival rates in the groups with less than 15% and more than 15% dedifferentiated components were 69% and 2%, respectively. The group with a more than 15% dedifferentiated component had significantly lower RFS rates than that with a less than 15% one (p=0.0001; log-rank test). In the DDLS groups with less than 15% and more than 15% dedifferentiated components, the median RFS rates were 25 months (95% CI 23-27) and 13 months (95% CI 8-18), respectively. In these groups, the 2-year RFS rates were equal to 50% and 9%, respectively. In the DDLS groups with less than 15% and more than 15% dedifferentiated components, pathologically confirmed invasion into the adjacent organs was observed in 32% and 63% of cases, respectively. There were no statistically significant differences in the OS and RFS of patients with DDLS according to tumor grade (p=0.069; p=0.102). CONCLUSION: This investigation suggests that DDLS have a more aggressive course with an increasing proportion of the dedifferentiated component in the tumor. Considering the histological variability in the dedifferentiated component, which is demonstrated in the research and scientific literature, as well as lack of a prognostic impact of histological grade, the authors believe that semi-quantitative assessment of the proportion of the dedifferentiated component in DDLS is able to serve as a simple and efficient morphological marker for the course of the disease and prognosis in retroperitoneal DDLS.

A Group of miRNA as Candidates for Prognostic Biomarkers of Gastric Cancer Metastasis.

An association was found between reduced expression of miR-34a, miR-146a with both metastasis to regional lymph nodes (relative risk RR=10.50 and RR=5.25, respectively) and the development of distant metastases (RR=9.50 and RR=4, 40, respectively) in gastric cancer. They are excellent classifiers: AUC>0.9 for both miRNAs. The association of miR-335 expression with metastasis to the lymph nodes is much weaker, but it is also a good classifier for identifying a group with distant metastasis (RR=5.90). A correlation was found between the expression of miR-34a and miR-146a during metastasis, which is absent in non-metastatic tumors. Thus, miR-34a, miR-146a, and miR-335 miRNAs can be proposed as candidates for biomarkers of the risk of gastric cancer metastasis.