No abstract

Expression of microRNAs is altered in cancer. Circulating miRNA level assessed in body fluids commonly reflects their expression in tumor cells. In leukemias, however, both leukemic and nonleukemic cells compose circulating miRNA expression profile of peripheral blood. The latter contribution to extracellular miRNA pool may result in specific microenvironmental signaling, which promotes proliferation and survival. In our study, we used qT-PCR to assay peripheral blood serum of 22 chronic lymphocytic leukemia (CLL) patients for the expression of 84 miRNAs associated with activation and differentiation of B and T lymphocytes. Results were analyzed regarding the most important prognostic factors. We have found that the general expression of examined miRNAs in CLL patients was lower as compared to healthy volunteers. Only miR-34a-5p, miR31-5p, miR-155-5p, miR-150-5p, miR-15a-3p, and miR-29a-3p were expressed on a higher level. Alterations of expression observed in CLL patients involved miRNAs associated both with B and T lymphocyte differentiation and activation. The most important discriminating factors for all functional miRNA groups were trisomy 12, CD38 expression, B2M level, WBC, and NOTCH1 gene mutation. Correlation of expression of miRNAs related to T lymphocytes with prognostic factors proves their supportive function in a leukemic microenvironment. Further studies utilizing a larger test group of patients may warrant the identification of circulating miRNAs that are key players in intercellular interactions and should be considered in the design of microenvironment-targeted therapies.Electronic supplementary materialThe online version of this article (doi:10.1007/s00277-016-2840-6) contains supplementary material, which is available to authorized users.

Epithelial cell adhesion molecule (EpCAM), which is expressed in the majority of epithelial tissues, exhibits tumor growth promoting abilities and is overexpressed in human epithelial ovarian cancer. Therefore, EpCAM is considered to be a promising target for specific immune-based therapies. The present study evaluated the role of IL-6 and IL-8 in the expression of EpCAM in the A2780 human ovarian cancer cell line. Furthermore, the cellular localization of the EpCAM protein in A2780 cells was determined and the effect of EpCAM inhibition on the proliferation of the A2780 cells was investigated. An MTT assay demonstrated that blocking EpCAM with anti-EPCAM antibodies had no effect on cellular metabolic activity (proliferation). Gene expression analysis revealed that IL-8 increased EpCAM expression, whereas IL-6 and the combination of IL-6/IL-8 had no effect on EpCAM expression. Immunofluorescence analysis confirmed that EpCAM is expressed on A2780 cell membranes. The present results demonstrated that IL-8 increased EpCAM expression at the mRNA level in ovarian cancer cells and suggested a potential role of IL-6 as an inhibitor of IL-8-stimulated EpCAM expression.

The results suggest that P72R polymorphisms may be associated with an increased PCM risk and may affect OS of PCM patients. However, we saw no consistent results of the polymorphism effect on apoptosis and necrosis in cell cultures derived from PCM patients. Further studies are need in this regard.