Silencing mouse circular RNA circSlc8a1 by circular antisense cA-circSlc8a1 induces cardiac hepatopathy.

Circular RNAs (circRNAs) are a group of non-coding RNAs with a unique circular structure generated by back-splicing. It is acknowledged that circRNAs play critical roles in cardiovascular diseases. However, functional studies of circRNAs were impeded due to lack of effective in vivo silencing approaches. Since most circRNAs are produced by protein-coding transcripts, gene editing typically affects the coding activity of the parental genes. In this study, we developed a circular antisense RNA (cA-circSlc8a1) that could silence the highly expressed circRNA circSlc8a1 in the mouse heart but not its parental Slc8a1 linear mRNA. Transgenic cA-circSlc8a1 mice developed congestive heart failure resulting in a significant increase in the body weight secondary to peripheral edema and congestive hepatopathy. To further test the role of circSlc8a1, we generated transgenic mice overexpressing circSlc8a1 and observed a protective effect of circSlc8a1 in a pressure overload model. Mechanistically, we found that circSlc8a1 translocated into mitochondria to drive ATP synthesis. While establishing a transgenic murine model for antisense-mediated circRNA silencing without interfering with the parental linear RNA, our finding revealed the essential role of circSlc8a1 in maintaining heart function and may lay the groundwork of using the circular antisense RNA as a potential gene therapy approach for cardiovascular diseases.

YAP Circular RNA, circYap, Attenuates Cardiac Fibrosis via Binding with Tropomyosin-4 and Gamma-Actin Decreasing Actin Polymerization.

Cardiac fibrosis is a common pathological feature of cardiac hypertrophy. This study was designed to investigate a novel function of Yes-associated protein (YAP) circular RNA, circYap, in modulating cardiac fibrosis and the underlying mechanisms. By circular RNA sequencing, we found that three out of fifteen reported circYap isoforms were expressed in nine human heart tissues, with the isoform hsa_circ_0002320 being the highest. The levels of this isoform in the hearts of patients with cardiac hypertrophy were found to be significantly decreased. In the pressure overload mouse model, the levels of circYap were reduced in mouse hearts with transverse aortic constriction (TAC). Upon circYap plasmid injection, the cardiac fibrosis was attenuated, and the heart function was improved along with the elevation of cardiac circYap levels in TAC mice. Tropomyosin-4 (TMP4) and gamma-actin (ACTG) were identified to bind with circYap in cardiac cells and mouse heart tissues. Such bindings led to an increased TPM4 interaction with ACTG, resulting in the inhibition of actin polymerization and the following fibrosis. Collectively, our study uncovered a novel molecule that could regulate cardiac remodeling during cardiac fibrosis and implicated a new function of circular RNA. This process may be targeted for future cardio-therapy.

The role of cytokeratin 19 levels in the determination of endometriosis stages.

OBJECTIVE/AIM: Endometrisosis, one of the most common gynecological disease, is characterized by the presence of endometriotic tissue outside of uterine cavity. The development and the validation of a simple blood biomarker specific and sensitive for endometriosis may facilitate the rapid and the accurate diagnosis of the disease and thus early treatment. Cytokeratin expression changes during epithelial differentiation and this expression is important for the modulation and the control of cell cycle regulation, tumor cell motility and apoptosis. Cytokeratin 19 (CK-19) is expressed in most simple epithelial cells and their malignant counterparts. The aim of this study is to investigate serum CK-19 expression levels in patients with endometriosis and to determine the diagnostic role of CK-19 levels in differentiating various stage of endometriosis. METHODS: Ctytokeratin-19 expression and level were studied in 70 endometriosis patients and 50 volunteers by ELISA and RT-PCR. ROC analysis was performed by comparing all stages with each other and with the control group. RESULTS: The CK-19 levels were significantly higher in the endometriosis groups than that of the control group by ELISA and RT-PCR. A significant (p < .05) difference was observed in endometriosis patients according to the stages. CONCLUSION: Based on our data, it suggests that Cytokeratin-19 may have a potential role in the development of endometriosis.

Biomarker potentials of miRNA-associated circRNAs in breast cancer (MCF-7) cells: an in vitro and in silico study.

Breast cancer is a heterogeneous disease, which is the most common malignancy in women. The incidence and mortality rates of breast cancer indicate that it is the leading cause of cancer-related with deaths. circRNAs operate as part of competing endogenous RNAs (ceRNAs) mechanisms, which play critical roles in the different biological processes of breast cancer such as proliferation, migration, and apoptosis. The goal of the present study is to identify the potential predictive biomarker for breast cancer diagnosis in the circRNA network by in vitro and in silico analyzes. 40 miRNAs were obtained from the miRWalk database and their combinatorial target genes (potential ceRNAs) were identified with ComiR. We stated that the cancer-specific circRNA genes in MCF-7 cells using the cancer-specific circRNA (CSDC) database, and obtained the ones showing potential ceRNA activity in our previous analysis among them. Identified genes with remarkable expression differences between BCa and normal breast tissue were determined by the GEPIA database. Moreover, the Spearman correlation test in the GEPIA database was used for the statistical analysis of the relationship between DCAF7 and SOGA1, SOGA1 and AVL 9, DCAF7 and AVL 9 gene pairs. And also, DCAF7, SOGA1, and AVL9 gene expression levels were detected in MCF-7 and MCF-10A cells by RT-qPCR method. DCAF7, SOGA1, and AVL9 gene were significantly more expressed to BCa tissue and MCF-7 cells than normal breast tissue and MCF-10 A cells. And also, DCAF7 and SOGA1, SOGA1 and AVL9, DCAF7 and AVL9 genes pairs were found to be significantly correlated with BCa. These genes may be considered as potential predictive biomarkers to discriminate BCa patients from healthy persons. Our preliminary results can supply a new perspective for in vitro and vivo studies in the future.

Determination of PD-1 expression in peripheral blood cells in patients with endometriosis.

In patients with endometriosis, ectopic endometrial tissues can escape from immune system control and survive in other tissues. The pathophysiology of endometriosis is still not fully understood. In this study, we aimed to clarify the pathophysiology of endometriosis, which is thought to be a benign but infiltrative cancer type, which has many similarities with cancer biology by determining PD-1 expression in patients with endometriosis. In this study, n = 73 cases who underwent surgery or examination at the Obstetrics and Gynecology Clinic of Sivas Cumhuriyet University Faculty of Medicine and diagnosed as endometriosis in the biopsy material taken with the pre-diagnosis of endometriosis constituted the patient group. The control group consisted of n = 64 healthy subjects without concomitant malignancy or chronic inflammatory disease. Venous whole blood samples were obtained from the study groups. PD-1 and PD-L1 levels were determined by the ELISA method from serum and plasma samples. PD-1 gene expression level was determined by RT-PCR. The PD-1 level was found to be approximately 350 ± 150 ng/L and 45 ± 17 ng/L in endometriosis and control group, respectively. While the PD-L1 level was approximately 760 ± 108 ng/L in the patients, this level was 140 ± 14 ng/L in the controls. According to the RT-PCR results, the expression of the PD-1 gene 10 times higher compared to the controls. Conclusion: The identified increase of PD-1 levels and gene expression in endometriosis groups show that immunotherapy may be used in the treatment of endometriosis.

Effect of Turkish Propolis on miRNA Expression, Cell Cycle, and Apoptosis in Human Breast Cancer (MCF-7) Cells.

Enriched in flavonoid compounds, phenol acids, and terpene derivatives, propolis has been shown to regulate apoptosis signaling pathways and alter the expression of microRNAs (miRNAs). In the present study, it has been aimed to examine the effects of Turkish propolis on miRNA levels of breast cancer (MCF-7) cells, and its relationship with cell proliferation and apoptosis. Cytotoxic activity of ethanolic propolis extract (EEP) was evaluated using MTT assay. Mechanisms involved in the cytotoxic action of Turkish propolis in MCF-7 cells were investigated with regard to apoptosis and cell cycle using flow cytometry and western blot. Mitochondrial membrane potential (MMP) were evaluated by spectrofluorometric method. miRNA levels were detected by qRT-PCR method. EEP exhibited selective toxicity against MCF-7 cells compared to normal fibroblast cells. EEP increased the cell cycle arrest at the G1 phase. EEP elevated the apoptotic cell death through increasing pro-apoptotic protein levels (p21, Bax, p53, p53-Ser46, and p53-Ser15), decreasing MMP and altering the expression levels of specific tumor suppressors (miR-34, miR-15a, and miR-16-5p) and oncogenic (miR-21) miRNAs. These data support that Turkish propolis may be evaluated as a potential natural agent for new anticancer drugs in future.

Antiproliferative and proapoptotic activity of Turkish propolis on human lung cancer cell line.

Cancer is a heterogeneous disease, two of whose characteristic features are uncontrollable cell proliferation and insufficient apoptosis. Various studies have investigated the antiproliferative effects of propolis, a natural bee product, from different countries, and its cytotoxic effects have been attributed to its polyphenol contents. The purpose of this study was to show the cytotoxic effects, and possible mechanisms involved, of ethanolic extract of Turkish propolis (EEP) on the human lung cancer (A549) cell line. Cytotoxic activity of EEP on A549 cells was revealed using the MTT assay. Mechanisms involved in the cytotoxic action of EEP on A549 cells were then investigated in terms of apoptosis, mitochondrial membrane potential and cell cycle using flow cytometry, endoplasmic reticulum stress using RT-PCR, and caspase activity using luminometric analysis. EEP exhibited selective toxicity against A549 cells compared to normal fibroblast cells. We determined that EEP arrested the cell cycle of A549 cells at the G1 phase, induced endoplasmic reticulum stress, caspase activity, and apoptosis and reduced mitochondrial membrane potential. These results indicate that Turkish propolis is capable of reducing cancer cell proliferation and may have a promising role to play in the development of new anticancer drugs in the future.

Specific expression and functions of circular RNAs.

In recent years, circular RNAs (circRNAs), a new class of RNA molecules characterized by their covalently closed circular structure, have become a new research paradigm in RNA biology. Many circRNAs are conserved among eukaryotes, localize in specific subcellular compartments, and play different biological roles. Accumulating evidence shows that circRNAs regulate a diversity of cellular processes by acting as miRNA sponges, anchors for circRNA binding proteins (cRBPs), transcriptional regulators, molecular scaffolds, and sources for translation of small proteins/peptides. The emergence of the biological functions of circRNAs has brought a new perspective to our understanding of cellular physiology and disease pathogenesis. Recent studies have shown that the expression of circRNAs is tissue- and cell type-specific and specifically regulated through development or disease progression, where they exert specific biological functions. However, the mechanisms underlying these remain largely unknown. A deeper understanding of how the specific expression of circRNAs is regulated to exert specific biological functions will enable the use of circRNA as a biomarker in clinical practice and the development of new therapeutic approaches. This review aims to summarize recent developments in circRNA biogenesis, functions, and molecular mechanisms. We also provide some specific circRNAs as examples to show their tissue-specific distribution and evaluate the possibility of applying circRNA technologies in molecular research and therapeutics.

circRNAs in drug resistance of breast cancer.

Breast cancer (BC) is the most common heterogeneous disease in women and one of the leading causes of cancer-related death. Surgery, chemotherapy, radiotherapy, hormone, and targeted therapy are the gold standards for BC treatment. One of the significant challenges during the treatment of BC represents resistance to chemotherapeutics, resistance that severely limits the use and effectiveness of the drugs used for BC treatment. Therefore, it is essential to develop new strategies to improve therapeutic efficacy. Circular RNAs (circRNAs) are a large group of non-coding RNAs that covalently form closed circular loops by joining their 5', and 3'; ends. Accumulating evidence suggests that circRNAs have a vital role in cancer development, progression, and BC resistance to chemotherapy. The purpose of this review is to discuss the biological properties of circRNAs, and how circRNAs induce resistance to conventional therapeutic anti-cancer drugs used in BC treatment, by emphasizing and summarizing the potential roles of circRNAs in mechanisms of drug resistance, such as drug efflux, apoptosis dysfunction, autophagy, and DNA damage repair. CircRNAs are associated with drug resistance via ATP-binding cassette (ABC) efflux transporters, while some others by inhibition of cell apoptosis, thus leading to resistance to tamoxifen in BC cells. In contrast, others are involved in the promotion of BC cells chemoresistance by doxorubicin-induced autophagy. CircRNAs may have clinical significance in regulating or overcoming BC drug resistance and may give directions towards a novel approach to personalized BC treatment. CircRNAs may significantly contribute to the identification of new therapeutic targets for the prevention of BC chemoresistance.

Circulating serum miR-200c and miR-34a-5p as diagnostic biomarkers for endometriosis.

OBJECTIVE: Endometriosis is defined by the presence of endometrial glands and stroma grow in areas outside the uterus. A simple blood test for endometriosis-specific biomarkers would offer a more timely accurate diagnosis of the disease and could lead to earlier treatment intervention. Alterations in microRNA (miRNA) levels in blood may reflect changes during normal physiologic processes and have been related to several pathologic conditions, including gynecologic diseases. In the present study, we aim to evaluate the level of serum miR-34a-5p and miR-200c from women with and without endometriosis, and to explore the potential of miRNAs as reliable non-invasive biomarkers in the diagnosis of endometriosis. METHODS: Expression levels of miRNAs were performed by quantitative real-time polymerase chain reaction (qRT-PCR). Serum cancer antigen 125 (CA-125) levels were analyzed by autoanalyzer. RESULTS: miR-34a-5p expression levels were decreased and miR-200c expression levels were increased in the endometriosis patients compared to the control group. According to the areas under the ROC curve (AUC) values, miR-200c and miR-34a-5p may serve as biomarkers for the diagnosis of endometriosis. Serum miR-34a-5p and miR-200c had a sensitivity of 78.95 % and 100 % and a specificity of 49.12 % and 100 %, respectively, for the detection of endometriosis. CONCLUSION: Serum miRNAs may provide a promising opportunity for diagnosis of endometriosis. Understanding the role of circulating miRNAs will serve a better comprehension of the systemic effects of endometriosis and offer options for new treatments. It is clear that more work is needed in this area.

Tetra-substituted phthalocyanines bearing thiazolidine derivatives: synthesis, anticancer activity on different cancer cell lines, and molecular docking studies.

In the first step, (4R)-2-(2-hydroxyphenyl)thiazolidine-4-carboxylic acid (c) and 2-(2-(3,4-dicyanophenoxy)phenyl)thiazolidine-4-carboxylic acid (1) were prepared. Then, the peripherally tetra-substituted metallophthalocyanines [ZnPc (2), CuPc (3), and CoPc (4)] were synthesized by using 1. The structures of the obtained compounds were characterized by common spectroscopic methods. Aggregation behaviors of the tetra-substituted metallophthalocyanines (2-4) were investigated by UV-Vis and fluorescence spectroscopy in the presence/absence of soft metal ions. The electronic spectra of the newly synthesized metallophthalocyanines [ZnPc (2), CuPc (3), and CoPc (4)] were analyzed by the Bayliss method. The fluorescence quantum yield of diamagnetic ZnPc (2) was obtained in DMSO at room temperature. Also, the anticancer activity of the newly synthesized metallophthalocyanine derivatives was studied on C6, DU-145, and WI-38 cell lines and investigated using six concentrations (3.125; 6.25; 12.5; 50; 75; 100 µg L-1). The cell cycle and apoptosis analyses of CuPc (3) were performed. In addition, the chemical and biological activities of 2-(2-(3,4-dicyanophenoxy)phenyl)thiazolidine-4-carboxylic acid (1) and its novel type metallophthalocyanines [ZnPc (2), CuPc (3), and CoPc (4)] were compared with many parameters obtained from the Gaussian software and molecular docking methods.

Cytotoxic activities of Hypericum perforatum L. extracts against 2D and 3D cancer cell models.

Six extracts were obtained from plant species Hypericum perforatum L., collected at Samsun in Turkey. The aim of this study was to examine the mechanisms of the anticancer activity of these extracts. Methanol, ethyl-acetate and hexane were used as a solvents for extraction from both branch-body part of the plant (extracts 1, 2 and 3) and from plant flowers (extracts 4, 5 and 6). The cytotoxic effects of the extracts were determined against 2D and 3D cancer cell models. Cell cycle changes of treated HeLa cells were analyzed by flow cytometry. Measurements of gene and microRNA expression levels in treated HeLa cells were done by quantitative real time PCR. Five examined extracts (2-6) exerted selective concentration-dependent cytotoxic effects on HeLa, K562, and A549 cancer cells, while the extract 1 exhibited very weak cytotoxicity. The extract 6 showed the highest intensity of cytotoxic activity. All tested extracts (2-6) demonstrated the ability to induce apoptosis in HeLa cells through activation of caspase-3. These extracts remarkably decreased gene expression levels of MMP2, MMP9, TIMP3, and VEGFA in HeLa cells. Flower extracts might have stronger effects on miR128/193a-5p/335 level changes than branch-body extracts. Hypericum perforatum extracts exerted weaker cytotoxic effects on 3D HeLa spheroids when compared with their effects on 2D monolayer HeLa cells. Taken together, results of our research may suggest the promising anticancer properties of the Hypericum perforatum extracts.

Evaluation of antioxidant and anticancer effects of Thymbra sintenisii subsp. isaurica extract.

BACKGROUND: The purpose of this study was to investigate the phenolic composition and antioxidant activity of Thymbra sintenisii subsp. isaurica extract (TSIE) and, to evaluate, for the first time, anticancer effect on human MCF-7 (breast carcinoma) cells. MATERIALS AND METHODS: The antioxidant capacity of TSIE was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and total polyphenol assays. The anticancer activities of TSIE were tested on MCF-7 (breast carcinoma) cells. RESULTS: Total polyphenol value of extracts TSIE was found as 73.02 mg gallic acid /g powder. DPPH result of IC50 value of TSIE was found to be 27.15 µg/mL. To examine anticancer effect of TSIE at different concentrations were given on MCF-7 cells. TSIE was observed to reduce the cell viability in a dose-dependent manner. This anticancer property of the TSIE provides a highlights the importance of plant research for drug design. CONCLUSION: In this study, anticancer effects and antioxidant level of endemic species, that is TSIE, are evaluated on MCF-7 cells. Thus, an effective therapeutic agent for cancer treatment is aimed to develop. Further studies are needed to better understand the molecular mechanisms underlying this effect of TSIE.

Circular RNAs serve as miRNA sponges in breast cancer.

Circular RNAs are a large group of non-coding RNAs with a closed-loop structure. circRNAs play significant roles in many biological processes as miRNA sponges, regulators for gene transcription, combining with RNA-binding proteins and translation of protein. Nowadays, circRNAs have become a research hotspot in the field of cancer and molecular biology. Accumulating evidences have indicated that circRNAs participate in the initiation and development of various cancers such as breast cancer. Breast cancer is a heterogeneous disease, which is the most common malignancy in women. The incidence and mortality rates of breast cancer indicate that it is the leading cause of cancer-related deaths. The goal of the present review is to introduce biogenesis, function characteristics and types of circRNAs, and also their biological functions on breast cancer, especially as miRNA sponges. Additionally, we discuss their use as a new therapeutic target for the treatment of breast cancer.

The effects of barnidipine on an experimental ischemia reperfusion model of spinal cord injury and comparison with methyl prednisolone.

OBJECTIVE: Increased intracellular calcium concentration plays an important role in the secondary mechanism of spinal cord injury. In the presenting experimental study, we aimed to evaluate the healing effect of barnidipine, which has a high affinity for L-type calcium channels, on acute spinal cord injury and to compare its effects with those of methylprednisolone. METHODS: A total of 32 Spraque Dawley albino adult female rats were divided into 4 groups; group 1: sham-operated (n=8), group 2: only ischemia (n=6), group 3: barnidipine-treated (n=8), and group 4: methylprednisolone-treated (n=6). An ischemia-reperfusion model was created by clipping the abdominal aorta in the rats. Motor examination was performed 1 hour after the surgical procedure and before sacrification. Immediately following the second motor examination, rats were sacrificed and tissue samples were taken for histopathological examination and for testing of tissue malondialdehyde (MDA) levels. RESULTS: A significant correlation of motor examination was found between the sham-operated and barnidipine-treated groups and the sham-operated and only ischemia groups at the 1st and 24th hour (p<0.008). There was no significant difference between the only ischemia and barnidipine-treated groups and only ischemia and methylprednisolone-treated groups (p>0.008). Light microscopic examination of the sham-operated group revealed findings consistent with normal spinal cord structure. In group 2, 3, and 4, light microscopic examination revealed polymorphonuclear leukocyte infiltration and a small amount of axonal swelling. There was no significant correlation between the ischemia and barnidipine-treated groups and the barnidipine and methylprednisolone groups in terms of MDA levels (p>0.008). CONCLUSION: A single dose of barnidipine (10 mg/kg) and methylprednisolone are not effective and not sufficient to prevent spinal ischemia-reperfusion injury in rats.

Silver nanoparticle/capecitabine for breast cancer cell treatment.

This study aimed to evaluate antiproliferative and proapoptotic effects of Capecitabine bonded silver particles on human breast cancer cells (MCF-7). Different sizes of Ag NPs (in sizes 5, 10, 15, 30 nm) were synthesized. The characterization of silver and drug-bonded silver nanoparticles was performed through UV-VIS, FTIR, and SEM analysis. Silver and drug-bonded silver nanoparticles were measured by zetasizer. Antiproliferative and proapoptotic effects of capecitabine, silver and drug-bonded silver nanoparticles were evaluated using XTT, Anneksin V, respectively. According to the results, silver nanoparticles of 10 nm size have shown the lowest toxic effect. Drug-bonded nanoparticles significantly increased the number of early and late apoptotic cells on MCF-7 cells.

Cytotoxic effect of Rosa canina extract on human colon cancer cells through repression of telomerase expression.

Rosa canina is a member of the genus Rosa that has long been used for medical objectives. Several studies have reported cytotoxic effects of different Rosa species, but there has been only limited investigation of the cytotoxic effect of R. canina. The purpose of the current study was to examine the potential effect of R. canina extract on cell viability, the cell cycle, apoptosis, and the expression of telomerase in human colon cancer (WiDr) cells. The cytotoxic effect of the extract was determined using MTT assay. The mechanism involved in the cytotoxic effect of the extract was then evaluated in terms of apoptosis and the cell cycle using flow cytometry. Mitochondrial membrane potential (MMP) was investigated using the fluorometric method, and expression levels of telomerase were studied using RT-PCR. R. canina extract exhibited a selective cytotoxic effect on WiDr cells compared with normal colon cells. The extract induced cell cycle arrest at the S phase and apoptosis via reduced MMP in WiDr cells. R. canina extract significantly repressed telomerase expressions at treatment times of 48 and 72 h in WiDr cells. Our results suggest that R. canina may have considerable potential for development as a novel natural product-based anticancer agent.

Evaluation of the radioprotective effect of Turkish propolis on foreskin fibroblast cells.

AIM OF STUDY: Propolis is a resinous bee product, rich of polyphenolic compounds and flavonoids. It is known that in different geographic zones its chemical composition varies due to the different plant sources. Many biological properties including antimicrobial, antioxidative, anti-inflammatory, antitumoral, antigenotoxic, antimutagenic, cytostatic activities have been ascribed to propolis. These biological effects are predominantly attributed to its content of polyphenols. In this study, we aimed to evaluate the radioprotective effect of ethanolic extract of Turkish propolis. (EETP) against γ-ray-induced DNA damage on fibroblast cells using comet assay for the first time. MATERIALS AND METHODS: Fibroblast cells were pretreated 15 and 30 min with concentrations of 100, 200 and 300 µg/mL EETP then they were exposed to 3 Gy γ-rays. Amifostine (synthetic aminothiol compound) was used as a positive control. RESULTS: The results showed a significant decrease in γ-ray-induced DNA damage on cells treated with EETP and amifostine when compared to only irradiated cells. (P < 001). CONCLUSION: It was concluded that EETP prevent γ-ray-induced DNA damage in fibroblast cells and might have radioprotective activity.