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.

[The content of the soluble forms PD-1 and PD-L1 in blood serum of patients with gastric cancer and their relationship with clinical and morphological characteristics of the disease.]

Results of comparative ELISA investigation of pretreatment sPD-1 and sPD-L1 content in blood plasma of 100 gastric cancer patients at various disease stages aged 25 to 81 years are presented. Control group included 60 practically healthy donors aged 18 - 68 years. Plasma sPD-L1 concentrations did not differ between gastric cancer patients and control group, and sPD-1 levels were statistically significantly lower in patients than in healthy donors (p<0.0001). Positive correlation (R=0.38; p=0.003) was revealed between plasma sPD-1 и sPD-L1 levels in control group and negative (R= -0.26; p=0,009) - in gastric cancer patients. ROC curve revealed the best sPD-1 cut-off level (< 21 pg/ml) with 77% sensitivity and 63.3% specificity, which is not sufficient for its application as diagnostic marker. Statistically significant increase of plasma sPD-L1 from stage I to stage IIIC (R=0.50; p=0.000011) was found. Analysis of associations between the evaluated markers' levels and indices of gastric cancer expansion according to TNM system revealed statistically significant positive associations of plasma sPD -L1 levels with T (tumor invasiondepth) and N (number of affected lymph nodes) indices: R=0.33; p=0.00093, and R=0.27; p=0.0099 respectively. sPD-L1 level was significantly increased in patients with low differentiated adenocarcinoma and cricoid-cell cancer as compared to highly differentiated adenocarcinoma (p=0.02 and p=0.004 respectively); in patients with cricoid-cell cancer it was also higher than in those with moderately differentiated adenocarcinoma (p=0.043) and undifferentiated cancer (p=0.049). Plasma sPD-1 level did not depend on disease stage, TNM system indices and tumor histological structure. Thus, soluble ligand sPD-L1, but not its receptor sPD-1, plasma level is increased in patients with unfavorable clinical and morphological characteristics, may be regarded as potentially valuable prognostic factor for gastric cancer patients' survival, and probably as a predictor of anti - PD-1/PD-L1 treatment efficiency.

Clinical Significance of Matrix Metalloproteinases in Blood Plasma of Patients with Gastric Cancer.

Plasma levels of MMP-2, MMP-7, and MMP-9 and their tissue inhibitor TIMP-2 were measured in 89 patients with gastric cancer and the relationship between these parameters and the main clinical morphological characteristics of the disease was analyzed. Plasma levels of the proteins were measured using standard direct ELISA kits. The level of MMP-7 in patients with gastric cancer was significantly higher than in the control group (medians 2.7 and 1.2 ng/ml, respectively; p<0.01), but only in 51% patients this parameter surpassed the upper threshold normal value (2.35 ng/ml; 95% percentile of control). The level of MMP-9 in gastric cancer patients was lower than in control group by 1.6 times (medians 167 and 267 ng/ml, respectively; p<0.01). Plasma levels of MMP-2 and TIMP-2 in patients with gastric cancer and healthy subjects were similar. No appreciable associations of plasma matrixins and TIMP-2 with the main clinical morphological characteristics of the disease were detected. The patients were followed up for 8 to 85 months (median 70.8 months). Low level of MMP-2 and high level of MMP-7 in the plasma proved to be unfavorable prognostic factors for overall survival. At MMP-2<268 ng/ml, the 5-year overall survival was 32% vs. 60% for patients with the marker level higher than this threshold value (p=0.016). The differences in overall survival in relation to their MMP-7 levels for 5-year observation did not surpass 16% (39% at marker level >2.7 ng/ml and 55% at lower level; p=0.048). Plasma levels of MMP-2 and TIMP-2 were not significantly associated with overall survival. Multivariate analysis showed that only T index (p=0.034) and plasma MMP-7 level (p=0.007) were essential for overall survival. The increase in plasma or serum MMP-7 levels is a universal phenomenon in tumors of different histogenesis, which precluded the use of this parameter as a specific diagnostic marker of gastric cancer. At the same time, it could be useful for monitoring the treatment efficiency and detection of relapses. In addition, high plasma level of MMP-7 remained an independent factor of unfavorable prognosis for overall survival of patients with gastric cancer.

[The growth factor of endothelium of vessels and its receptors type I and II in blood serum in patients with kidney cancer: clinical morphological correlations.]

The progress in treatment of kidney cancer is related to application of anti-angiogenic medications. Therefore, investigation and searching for new molecular markers characterizing its angiogenic activity is actual still. The purpose of study is to compare VEGF, VEGFR1 and VEGFR2 in blood serum of healthy people, patients with cancer and benign tumors of kidney and to analyze their relationship with main clinical morphological characteristics of neoplasms. The study sampling consisted of 94 patients with cancer and 10 patients with benign tumors of kidney. The control group included 80 individuals. The concentration of analyzed proteins was determined using QuantikineТ (R&D Systems, USA), a reagents' kit for direct immune enzyme analysis. The content of VEGF, VEGFR1 and VEGFR2 in blood serum of patients with cancer of kidney was reliably higher than in control group. The level of VEGF also was increased in patients with benign tumors. Under threshold level of VEGF of 365 pg/ml the diagnostic sensitivity of detection of primary cancer of kidney amounted to 67% and specificity - 70%. The stage of disease and T and N indices were correlated only with VEGFR1 level. The relationship between level of markers and histological structure and degree of differentiation of cancer of kidney was not established. Therefore, VEGF and its receptors have a limited diagnostic value under cancer of kidney but they can be applied for monitoring and prognosis of efficiency of anti-angiogenic therapy.

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.

[Granulomatous thymitis with stromal amyloidosis]. / Ganulomatoznyi timit s amiloidozom stromy.

In a surgically removed thymus of an 18 year old man granulomatous thymitis with lymphoid follicles, amyloidosis, pseudocysts were observed. Rare occurrence of this pathology, difficulty of the diagnosis, absence of the treatment concept make surgery a method of choice.

[The role of epithelial antigens in diagnosis and staging of breast cancer]. / Rol' épitelial'nykh antigenov v diagnostike i stadirovanii raka molochnoi zhelezy.

The study of different epithelial antigen expression has been performed in 183 breast cancers. In 73 patients regional lymph nodes were studied as well. Panepithelial antigen Egp-34 (Mab HEA-125) was expressed in 100% of primary tumors and metastases. Antigen MUC-1 (Mab ICO-25) was identified in 93% of breast cancers. Monomorphic type of expression in tumor cells was typical for Egp-34, MUC-1 being in certain cases expressed as a proportion of cells. Additional immunohistochemical study of regional lymph nodes with Mab to Egp34 and MUC-1 provides a 10% increase in the rate of breast cancer metastases detection compared to histological examination alone. The carcinoembryonic antigen (CEA) was useful in identification of metastases only in CEA-positive breast cancers.

[Urokinase and tissue type plasminogen activators and their type-1 inhibitor (PAI-1) in gastric cancer]. / Aktivatory plazminogena urokinaznogo i tkanevogo tipov i ikh ingibitor PAI-1 pri rake zheludka.

The levels of urokinase (uPA) and tissue type (tPA) plasminogen activators and their type 1 inhibitor (PAI-1) were determined by immunoassay in tumor cytosols and samples of histologically unaltered adjacent mucosa in gastric cancer patients. Gastric tumor revealed enhanced uPA and PAI-1 matched by decreased tPA in intact mucosa. The expression of uPA and PAI-1 was particularly was high at the later stages of the disease. The concentrations of uPA in tumor tissue increased with age. No significant correlation was established between levels of plasminogen activation system components, on the one hand, and histopathological grading of tumor, on the other.

[Magnetic resonance imaging in diagnosis of localized prostatic cancer]. / Magnitno-resonansnaia tomografiia v diagnostike klinicheski lokalizovannogo raka predctatel'noi zhelezy.

To evaluate efficacy of MR imaging (MRI) in diagnosis of local prostatic cancer (LPC) and validity of MRI performance in patients with high levels of prostate-specific antigens (PSA), we made a retrospective analysis of a combined examination of 210 patients including MRI (100%). Of them, 68 (32.4%) had prostatic cancer (LPC pT1-pT2 in 27 patients, 39.7%), 87 (41.4%) had benign prostatic hyperplasia (BPH) and 35 (16.7%)--chronic prostatitis (CP). 17 (8.1%) patients were free of prostatic diseases. MRI accuracy in diagnosis of LPC was 60%, sensitivity 70%, specificity 54%, in positive and negative prognostic values 50 and 73%, respectively. Some features of LPC were seen in MRI of BPH, CP and control patients. MRI symptoms characteristic for one of the above diseases only were not determined. We believe that MRI is indicated in suspected prostatic cancer located in the central zone and anterior lateral regions of the peripheral zone (unpalpable prostatic cancer). Prostatic MRI with assessment of the lower spine and pelvic bones is justified in men over 50 years if PSA is above 10 ng/ml. Early and accurate diagnosis of LPC by MRI is impossible without evaluation of clinical and PSA data.