17 research outputs found
Enhanced Anti-cancer Potency Using a Combination of Oleanolic Acid and Maslinic Acid to Control Treatment Resistance in Breast Cancer
Purpose: The phosphatidylinositol 3-kinase/AKT/mammalian target of rapamycin (PI3K/AKT/ mTOR) pathway is a complex intracellular metabolic pathway that leads to cell growth and tumor proliferation and plays a key role in drug resistance in breast cancer. Therefore, the anti-cancer effects of oleanolic acid (OA), maslinic acid (MA), and their combination were investigated to improve the performance of the treatment strategy. Methods: We investigated the effect of OA and MA on cell viability using the WST-1 method. The synergistic effect of the combination was analyzed by isobologram analysis. In addition, the effects of the two compounds, individually and in combination, on apoptosis, autophagy, and the cell cycle were investigated in MCF7 cells. In addition, changes in the expression of PI3K/AKT/mTOR genes involved in apoptosis, cell cycle and metabolism were determined by quantitative RT-PCR. Results: MA, OA, and a combination of both caused G0/G1 arrest. Apoptosis also increased in all treated groups. The autophagosomal LC3-II formation was induced 1.74-fold in the MA-treated group and 3.25-fold in the MA-OA-treated group. The combination treatment resulted in increased expression of genes such as GSK3B, PTEN, CDKN1B and FOXO3 and decreased expression of IGF1, PRKCB and AKT3 genes. Conclusion: The results showed that the combination of these two substances showed the highest synergistic effect at the lowest dose and using MA-OA caused cancer cells to undergo apoptosis. The use of combination drugs may reduce the resistance of cancer cells to treatment
Telomerase inhibition regulates EMT mechanism in breast cancer stem cells
Avci, Cigir Biray/0000-0001-8251-4520; Gunduz, Cumhur/0000-0002-6593-3237; Kusoglu, Alican/0000-0002-7394-2416WOS: 000566791200008PubMed: 32738420Backround: CSCs having the common features of high telomerase activity and high migration and invasion capabilities play a vital role as the initiators of metastasis. Small molecule BIBR1532 has been shown to target cancer cells by inhibiting telomerase. Recent studies have suggested that telomerase activity is associated with epithelial mesenchymal transition (EMT). EMT program, which causes epithelial cells to acquire a mesenchymal morphology, is known to play a significant role in cancer metastasis. Methods: the hypothesis of our study was that suppression of telomerase in breast cancer and cancer stem cells would interrupt EMT mechanism. Cytotoxicity of BIBR1532 was evaluated using WST-1 assay in all cell lines and the effects of BIBR1532 on apoptosis were investigated with Annexin V. Migration rate of the cells was examined by wound healing assay and sphere forming capacities were observed by hanging drop test. Finally, the expression of 84 EMT-related genes was analyzed by real-time qPCR. Results: the IC50 values for the MDA-MB-231 and breast epithelial stem cells of BIBR1532 were analyzed as 18.04 and 38.71 mu l at 72 h, respectively. Interestingly, apoptosis was only induced in stem cells. in hanging drop test, sphere areas were reduced in stem cells treated with BIBR1532. in wound healing assay, BIBR1532 decreased the migration rate of stem cells. Together with this, expression of EMT-related genes were regulated in stem cells towards a epithelial phenotype. Conclusion: Our obtained results indicated that telomerase inhibition affects the EMT mechanism. the targeted elimination of breast cancer stem cells by a telomerase inhibitor in cancer treatment may limit the mobility and stemness of cancer cells interrupting the EMT mechanism, thus may prevent metastasis.Research Foundation of Ege University Medical SchoolOur study is supported by Research Foundation of Ege University Medical School
Effects of telomerase inhibitor on epigenetic chromatin modification enzymes in malignancies
WOS: 000450130500019PubMed ID: 30145821Telomerase has a critical role in cell proliferation, tumor maintaining, and therapy resistance, which act by modifying many signaling pathways. 2-[(E)-3-Naphtalen-2-yl-but-2-enoylamino]-benzoic acid (BIBR1532) is one of the most studied telomerase inhibitors, and it targets telomerase components TERC and TERT. In this novel study, we aimed to investigate the epigenetic effects of BIBR1532 on both hematologic malignancies and solid tumors. K-562 human chronic myeloid leukemia cell line and U87MG glioblastoma cell line were compared with control groups without BIBR1532 treatment. Cytotoxic effects of BIBR1532 were determined by using WST-1 assay. Apoptotic effects of BIBR1532 were detected by using annexin V method. To assess expression changes in the human epigenetic chromatin modification enzyme genes, total RNA was isolated from K-562 and U87MG cells treated with BIBR1532 and untreated control cells. BIBR1532 induced 2.41-fold apoptotic cell death in U87MG cell lines compared with control groups. Apoptosis was slightly induced in K-562 cells with BIBR1532 treatment compared with control cells. We observed that BIBR1532 also regulates similar genes in both cell lines, and it is useful on epigenetic mechanisms. As a result, telomerase inhibitor BIBR1532 has a significant effect on both hematological malignancies and solid tumors
Effects of rapamycin and AZD3463 combination on apoptosis, autophagy, and cell cycle for resistance control in breast cancer
sogutlu, fatma/0000-0002-1210-7660WOS:000600546400042PubMed: 33141044Breast cancer is the most common cancer in women and the leading cause of cancer mortality in women over 40 it's the year. The existence of the PI3K/AKT/mTOR pathway aberrations in more than 70% of breast cancer has caused to become a therapeutic target. AZD3463 is an anti-cancer agent used as a potential inhibitor of ALK/IGF1R. It also induces apoptosis and autophagy of the PI3K/AKT/mTOR pathway in cancer cells. Although the mTOR signaling might be inhibited by rapamycin treatment, signals transmitted from the upstream pathway supports cell survival and proliferation. The WST-1 assay test was performed to evaluate the anti-proliferative effects of rapamycin and AZD3463. Besides, the effects of them on apoptosis, autophagy, cytostatic, and metabolism in MCF7 breast cancer cells were investigated. Also, changes in the expression of apoptotic regulatory genes, cell cycle, and metabolism in the PI3K/AKT/mTOR Pathway were determined by Quantitative RT-PCR. The results showed that rapamycin and AZD3463 treatments significantly reduced survival in MCF7 cells. Also, apoptosis, autophagy, and cell population in the G0/G1 stage in the MCF7 cell category in the treatment group showed an increase compared to the control group. The combination of rapamycin and AZD3463 (AZD-RAPA) was determined as an additive according to isobologram analysis. in the combination of rapamycin with AZD3463, the expression of CDKN1B, PTEN, FOXO3, and APC genes increases, and the expression of PRKCB and PIK3CG genes decreases. Our results showed that the use of AZD-RAPA reduced the resistance of cancer cells to treatment and it leads cancer cells to apoptosis
Combination of resveratrol and BIBR1532 inhibits proliferation of colon cancer cells by repressing expression of LncRNAs
Colorectal cancer (CRC) is the third most common cancer worldwide. The development of tumor drug resistance is observed in the treatment of CRC. Combinations of anticancer agents are attracting considerable interest in order to overcome drug resistance in CRC. This study aims to investigate the effect of resveratrol and BIBR1532, either alone or in combination, on the cell viability as well as on expression of long non-coding RNAs (LncRNAs) for HT-29 colon adenocarcinoma cells. The cytotoxic effects of resveratrol and BIBR1532 on HT-29 cells were determined using WST-1 test. Flow cytometry was used to determine apoptotic cell death after treatments. Real-Time PCR was used to identify expression of LncRNAs after treatments. LncExpDB and GEPIA2 were used to evaluate expression profiles of LncRNAs, whose expression levels were decreased in HT-29 cells after treatments, in normal tissues and colon adenocarcinoma tumors. IC50 concentrations of BIBR1532 and resveratrol were found to be 50.81 mu M at 48 h and 86.23 mu M at 72 h, respectively. Combination index value was 1.07617. BIBR1532, resveratrol, or their combination reduced the cell viability of HT-29 cells. CCAT1, CRNDE, HOTAIR, PCAT1, PVT1, SNHG16 were down-regulated after treatments. In silico analysis revealed that LncRNAs whose expression levels were decreased after treatments were associated with CRC. Resveratrol, BIBR1532, or their combination may have anti-proliferative effect on colorectal cancer cells through repressing expression of LncRNAs that are involved in progression of CRC.Ege University Research Fund [TYL-2019-20515]This study was sponsored by Ege University Research Fund, Project No. TYL-2019-20515 (to Cigir Biray Avci)
Effect of valproic acid on miRNAs affecting histone deacetylase in a model of anaplastic thyroid cancer
Background Thyroid cancer is the most common malignant tumor of the endocrine system seen in the thyroid gland. More than 90% of thyroid cancers comprise papillary thyroid cancer (PTC) and follicular thyroid cancer (FTC). Although anaplastic thyroid carcinoma (ATC) accounts for less than 2% of thyroid cancer. But patients' lifespan after diagnosis is about 6 months. Surgical interventions, radioactive iodine use, and chemotherapy are not sufficient in the treatment of ATC, so alternative therapies are needed. Methods and results The WST-1 assay test was performed to evaluate the anti-proliferative effects of Valproic acid (VPA). Also, the effect of VPA on miRNAs affecting histone deacetylase was determined by Quantitative RT-PCR. In the SW1736 cell line, IC50 dose for VPA was found 1.6 mg/ml. In our study, the level of oncogenic genes expression in cells treated with VPA, including miR-184, miR-222-5p, miR-124-3p, and miR-328-3p, decreased. Also, the expression of tumor inhibitory genes including miR-323-5p, miR-182-5p, miR-138-5p, miR-217, miR-15a-5p, miR-29b-3p, miR-324-5p and miR-101-5p increased significantly. Conclusions VPA can ad-just countless gene expression patterns, including microRNAs (miRNAs), by targeting histone deacetylase (HDAC). However, further studies are required for more accurate results
Evaluation of significant gene expression changes in congenital and acquired cholesteatoma
Avci, Cigir Biray/0000-0001-8251-4520WOS: 000554430700001PubMed: 32740796Etiopathogenesis of acquired and congenital cholesteatoma is still unclear. the clinical behavior of adult acquired, pediatric acquired and congenital cholesteatomas show differences. the scope of the this study was to detect thematrix metalloproteinase(MMP),tissue inhibitors of metalloproteinase(TIMP) andepidermal growth factor receptor(EGFR) gene expression changes in cholesteatoma perimatrix and to compare these changes among congenital cholesteatoma, adult acquired cholesteatoma and pediatric acquired cholesteatoma. A total of 16 genes includingMMPs,TIMPs andEGFRwere analyzed in the samples of 32 cholesteatoma tissues. Real-time PCR was used for detection of the gene expression levels. Data analyses were achieved by Delta Delta CT method (Light Cycler 480 Quantification Software) and Statistical Package for Social Sciences (SPSS) version 22.0. the expression levels ofMMP-2,-9,-10,-11,-13,-14,-15,-16andEGFRgenes were significantly higher in acquired cholesteatoma than healthy tissue (p < 0.05). There was a statistically significant decrease (3.34 times more) in the meanTIMP-2gene expression level in acquired cholesteatoma compared to healthy tissue (p < 0.05). There was a significant increase in the mean expression level ofMMP-7gene and a decrease in the mean expression level ofTIMP-1gene (3.12 times more) in congenital cholesteatoma compared to healthy tissue (p < 0.05). This study indicates that increased expression levels of some particularMMPgenes andEGFRgene and decreased expression levels ofTIMPgenes may play an important role in the development of cholesteatoma. Further,MMP-9,MMP-13andMMP-14genes may have a remarkable role in the development of more aggressive cholesteatoma forms. the authors concluded that overexpression ofMMP-9,MMP-13andMMP-14may cause stronger inflammation associated with cholesteatoma