Molecular Approach to Neuroblastoma

Neuroblastoma is a notably malignant cancer originates from neuroblastoma stem cells during embryogenesis. It can originate from any region of the peripheral nervous system. Neuroblastoma is a heterogeneous cancer. The cells responsible for heterogeneous structure are neuroblastoma stem cells that initiate the cancer and generate into all the cancer cells and have self‐renewal property. Although some specific surface markers and genetic patterns of neuroblastoma stem cell were determined, all mechanisms have not been illuminated yet. Mutations that are specific to neuroblastoma development, risk group, and disease‐stage are identified. However, epigenetic dysregulations also play major roles in the development of neuroblastoma. Patients gradually develop resistance to conventional chemotherapy or relapse occurs after treatment. New therapy approaches have been developed, either as alternatives to conventional chemotherapy, or in combination with it, in order to overcome the handicaps. Targeted therapies, those directly affecting the cancer cell or the cancer stem cell and having a minimal effect on healthy cells, constitute these approaches. Since neuroblastoma is highly heterogeneous both genetically and epigenetically, the data obtained from molecular mechanisms will greatly contribute to the survival of patients

ANASTASIS IN GLIOBLASTOMA, BRAIN CANCER STEM, AND BRAIN STEM CELLS

Objective: Anastasis, a process that has been discovered recently, halts apoptosis, and thus, recovers the survival functions of cells. It may be suggested that anastasis is related to cancer progression, especially in cancer stem cells which are responsible for therapy resistance, metastasis, and recurrence. In this study, the investigation of the anastasis phenomena and its effect on stemness related gene expressions of brain cancer-related cells are aimed. Methods: In this study commercially obtained glioblastoma multiforme (GBM), brain cancer stem cells (BCSC), and brain stem cells (BSC) were used for in vitro models. To induction of apoptosis 4% ethanol including medium was used. Annexin V assay was used for confirmation of apoptotic and anastatic status. Gene expression profile was determined real-time qRT-PCR method and fold changes were calculated by using 2(-Delta Delta Ct) method. Ingenuity Pathway Analysis was used for the functional pathway and upstream regulatory analysis. Results: A common decrease in the expression of stemness related genes in GBM cells was determined by real-time qRT-PCR performed on anastatic cells. Although BSCs showed a similar expression profile with GBM cells, all stemness genes were upregulated in BCSCs. Similar to expression profile, the canonical pathways were markedly down-regulated in BSC and GBM, while they were up-regulated in BCSC. Differently, it is determined that the activation of self-renewal in GBM and BCSC, unlike BSC. Conclusion: We have demonstrated that the inhibition of anastasis may be used to prevent the malignant transformation of healthy stem cells and the aggression of cancerous stem cells. Anastasis may be suggested as a critical mechanism that supports uncurable cancers

PI3K/AKT/mTOR pathway and autophagy regulator genes in paranasal squamous cell carcinoma metastasis

Avci, Cigir Biray/0000-0001-8251-4520WOS: 000528158000002PubMed: 32319010Although there are many studies on the role of PI3K/AKT/mTOR pathway and autophagy genes in the mechanism of head and neck cancer formation and prognostic significance, there is no study investigating the role of the genes in paranasal sinus carcinomas. the aim of the study was to assess the role of the PI3K/AKT/mTOR pathway and autophagy related gene expression changes in squamous cell carcinoma of paranasal sinuses with and without neck metastasis. Eight paranasal squamous cell carcinoma patients (five without and three with neck metastasis) were included. Tissues were obtained during the surgery. Total RNA was isolated from the tissues and cDNA synthesis was performed. Expression levels of the genes were determined using qRT-PCR method. the results were evaluated using the 2(- increment increment Ct) method, and fold changes of the gene expression levels in primary tumor and neck metastasis tissues were calculated according to the normal tissue. Expression levels of both PI3K/AKT/mTOR pathway and positive regulators of autophagy were significantly increased in metastasis-related two groups, especially in neck metastasis tissues. the increase in PI3K/AKT/mTOR pathway and autophagy related gene expression levels may support the metastatic character in paranasal squamous cell carcinomas. This is the first study to assess autophagy related genes in paranasal sinus cancer at transcriptome-level. Support of the transcriptome-level findings by the further protein analyses will contribute to the illumination of the rare paranasal sinus cancer molecular biology

In Vitro Effects of Propofol on Cytotoxic, Apoptotic and PI3K-Akt Signaling Pathway Genes on Brain Cancer Cells

Aim: The study aimed to determine the cytotoxic and apoptotic effect of propofol on glioma cells. Background: Propofol [2,6-diisopropylphenol] is a commonly used intravenous anesthetic. Propofol is known to have a mechanism of action on the PI3K-AKT pathway. Objective: This study aimed to evaluate the effect of propofol on the proliferation and apoptosis of human glioma cells, as well as to investigate changes in expression levels of the PI3K-AKT signaling pathway genes. Materials and Methods: The cytotoxic effect of propofol on the U-87 MG cell line was determined by WST-1 method. Annexin V-FITC and Mitoprobe JC-1 assay were used to measure apoptosis by flow cytometry. The expression levels of genes in the PI3K-AKT signaling pathway were investigated by qRT-PCR. Results: We have shown that propofol induced apoptosis in U-87 MG cells by 17.1 fold compared to the untreated control. Furthermore, significant differences were found in the expression levels of the PI3K-AKT signaling pathway genes. Conclusion: As a result of our study, it was found that propofol caused differences in expression levels of PI3K-AKT signaling pathway genes and it was suggested that these differences may be related to apoptosis induction

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

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)