Marcin Opławski

miRNAs Participate in the Regulation of Oxidative Stress-Related Gene Expression in Endometrioid Endometrial Cancer

Reactive oxygen species are formed as by-products of normal cell metabolism. They are needed to maintain cell homeostasis and signaling, which is possible due to defense systems. Disruption of this balance leads to oxidative stress that can induce cancer. Redox regulation by miRNAs may be a potential therapeutic target. The aim of the study was to assess the activity of genes associated with oxidative stress in endometrial cancer and to determine their relationship with miRNAs. The study included 45 patients with endometrioid endometrial cancer and 45 without neoplastic changes. The expression profile of genes associated with oxidative stress was determined with mRNA microarrays, RT-qPCR and ELISA. The miRNA prediction was performed based on the miRNA microarray experiment and the mirDB tool. PRDX2 and AQP1 showed overexpression that was probably not related to miRNA activity. A high level of PKD2 may be the result of a decrease in the activity of miR-195-3p, miR-20a, miR-134. A SOD3 level reduction can be caused by miR-328, miR-363. In addition, miR-363 can also regulate KLF2 expression. In the course of endometrial cancer, the phenomenon of oxidative stress is observed, the regulation of which may be influenced by miRNAs.

Variances in the Level of COX-2 and iNOS in Different Grades of Endometrial Cancer

Background:Many experimental studies have demonstrated the importance of COX-2 in the tumor angiogenesis. Inducible iNOS is responsible for a high and stable level of nitric oxide and is expressed in response to pro-inflammatory factors.Objective:The aim of this study was to evaluate the expression of COX-2 and iNOS at the protein level and to assess their potential prognostic significance in patients with endometrial cancer.Methods:The study group consisted of 45 women with endometrial cancer divided according to the degree of histological differentiation i.e. G1, 17; G2, 15; G3, 13. The control group consisted of 15 women without neoplastic changes. The expression of studied proteins was determined immunohistochemically with specific polyclonal antibodies.Results:Analysis of the COX-2 expression showed that the optical density of the reaction product in G1 reached 186% in the control group, while the values in G2 and G3 reached 243% and 293%, respectively. In the case of iNOS, the optical density of the reaction product reached the following percentages in the control group: 147% in G1, 243% in G2, and 241% in G3.Conclusions:Our findings suggest that changes in the expression of COX-2 and iNOS may be potentially useful in predicting the progression of endometrial cancer and treatment effectiveness.