Esra Gunduz

Leptin induces ADAMTS-4, ADAMTS-5, and ADAMTS-9 genes expression by mitogen-activated protein kinases and NF-ĸB signaling pathways in human chondrocytes.

Elucidation of the causes of inflammation has vital importance in the development of new approaches for the treatment of arthritic diseases. The degradation of aggrecan by upregulated disintegrin and metalloproteinase with trombospondin motifs (ADAMTSs) is the key event in the development of both rheumatoid arthritis (RA) and osteoarthritis (OA). Increased levels of leptin in both RA and OA have been demonstrated, thus linking leptin to arthritic diseases, but the mechanism has not been clarified. This study investigated the putative role of signaling pathways (p38, JNK, MEK1, NF‐ĸB, and PI3) involved in leptin‐induced cartilage destruction. Normal human articular chondrocytes were cultured with recombinant human leptin at 100, 250, 500, and 1000 ng/mL doses for 6, 12, 24, and 48 h, after which ADAMTS‐4, ‐5, and ‐9 genes expression were determined by real time‐polymerase chain reaction (RT‐PCR) and Western Blot methods. The signaling pathways involved in leptin‐induced ADAMTSs upregulation were also investigated by using inhibitors of signaling pathways. It was demonstrated that ADAMTSs expression level was peaked at 1000 ng/mL doses for 48 hours, and MAPKs (p38, JNK, and MEK) and NF‐ĸB signaling pathways involving in leptin triggered ADAMTSs upregulation. Obesity as a risk for RA and OA may contribute to the inflammation of both RA and OA diseases by secreting adipokines like leptin. We hypothesize that leptin is involved in the development of RA and OA accompanied with obesity by increasing ADAMTS‐4, ‐5, and ‐9 genes expression via MAPKs and NF‐ĸB signaling pathways.

Relationship between cytosine-adenine repeat polymorphism of ADAMTS9 gene and clinical and radiologic severity of knee osteoarthritis

The aim of this study is to determine the role of cytosine‐adenine (CA) micro‐satellite repeat sequence of ADAMTS9 gene on the development and progression of osteoarthritis (OA).

Is There a Relationship Between Pelvic Organ Prolapse and Tissue Fibrillin-1 Levels?

PURPOSE Pelvic organ prolapse is a multifactorial disorder in which extracellular matrix defects are implicated. Fibrillin-1 level is reduced in stress urinary incontinence. In Marfan syndrome, which is associated with mutations in Fibrillin-1, pelvic floor disorders are commonly observed. We hypothesize that Fibrillin-1 gene expression is altered in pelvic organ prolapse. METHODS Thirty women undergoing colporrhaphy or hysterectomy because of cystocele, rectocele, cystorectocele, or uterine prolapse were assigned to a pelvic prolapse study group, and thirty women undergone hysterectomy for nonpelvic prolapse conditions were assigned to a control group. Real-time polymerase chain reaction was conducted on vaginal tissue samples to measure the expression of Fibrillin-1. Expression levels were compared between study and control groups by Mann-Whitney U test with Bonferroni revision. RESULTS Fibrillin-1 gene expression was not significantly lower in the study group than in the control group. Similarly, no significant correlation between Fibrillin-1 levels and grade of pelvic prolapse was found. Age over 40 years (P=0.018) and menopause (P=0.027) were both associated with reduced Fibrillin-1 levels in the pelvic prolapse group, whereas the delivery of babies weighing over 3,500 g at birth was associated with increased Fibrillin-1 expression (P=0.006). CONCLUSIONS The results did not indicate a significant reduction in Fibrillin-1 gene expression in pelvic prolapse disorders; however, reduced Fibrillin-1 may contribute to increased pelvic organ prolapse risk with age and menopause. Increased Fibrillin-1 gene expression may be a compensatory mechanism in cases of delivery of babies with high birth weight. Further studies are needed for a better understanding of these observations.

Functional analysis of ESM1 by siRNA knockdown in primary and metastatic head and neck cancer cells

BACKGROUND Genetic factors play a large role in cancer, and thus, there is a great desire to understand the effects of different genes in cancer and to also develop gene therapy for better treatments. Therefore, the development of alternative diagnosis and therapy modalities is of utmost importance. The aim of our study was to illuminate the role of ESM1 (endothelial cell-specific molecule-1, also known as Endocan) in proliferation and migration of head and neck cancer, thus helping to pave the way for new treatment modalities and predictive biomarkers. METHODS ESM1 expression was shown with immunofluorescence assay using confocal laser scanning microscope in primary and metastatic head and neck cancer cells. ESM1 expression was knocked down by RNA interference in head and neck cancer cells. Knockdown efficiency was evaluated by quantitative real-time RT-PCR and Western blot. Cell proliferation and migration assays were performed by xCELLigence real-time cell analysis system. RESULTS Immunofluorescence assay showed nuclear localization and high expression of ESM1 in primary and metastatic head and neck cancer cells. ESM1 mRNA and protein levels were significantly decreased in ESM1-knockdown cells compared to control. ESM1-knockdown cells showed reduced proliferation and migration activity when compared to control cells. CONCLUSION These findings suggest that ESM1 has roles on proliferation and migration of head and neck cancer cells.

Tissue Engineering: Towards Development of Regenerative and Transplant Medicine

Abstract Tissue engineering is a top scientific branch, which is often named as “regenerative medicine” mistakenly, which uses the combination of engineering principles and the knowledge of cell biology and materials sciences to improve or replace the functions of tissues and organs. This field provides a variety of options from repairing the damaged tissues through building new organs for transplant surgeries. Apart from the regenerative medicine, tissue engineering, additional to the use of stem cell culturing and differentiation techniques, is taking the advantage of using biodegradable and biosafe materials such as polyesters and collagen to form versatile structures called “scaffolds.” Recently, by the developments of stem cell technology, it became possible to generate a tissue or an organ from the patient himself/herself without using these materials that pose a great opportunity to tackle the problems we face today, like the cancellation of the transplant. In the future, by means of improvements in tissue engineering industry, it is foreseen to establish their organ banks from the healthy citizens and to test the effects of drugs on tissues and multiorgan systems, which end up with the personalized medicine.

Genetic Basis of Metastasis

The variation between and among the many types of cancer presents a formidable challenge both to practicing clinicians and medical researchers. There are several characteristics that are common to all cancers such as unrestrained proliferation and evasion of cell death. Another common feature is that of metastasis. Metastasis is “initiated” when primary tumor cells acquire the ability to invade surrounding tissues and eventually develop secondary tumors in distant locations. This process appears to rely not only on changes at the genetic level of tumor cells themselves but also from their interaction with surrounding stromal cells and the immune system. The genetic and molecular changes that give rise to metastatic change are of special interest due to the significant decline in a patient’s prognosis after metastasis has occured. A host of genes and pathways involved in several pathways have been implicated in this process, several of which will be reviewed in detail.

Abstract 1399: Characterization of cancer stem cell properties and identification of invasion as well as metastatic process in head and neck cancer

Proceedings: AACR 106th Annual Meeting 2015; April 18-22, 2015; Philadelphia, PA Cancer stem cells (CSC) are thought to be a sub-population of cancer cells, which are the main tumorigenic cells in the tumors. Although chemoradiotherapy may kill the majority of rapidly dividing cells, CSC-like cell populations may be left behind due to their low turnover and infrequent cell cycling. In 2007, Prince et al. reported the presence of head and neck cancer stem cells for the first time. In the current study, UTTSCC74A and UTTSCC74B head and neck cancer cell lines as material derived from the primary tumor and their lymph node metastasis, respectively, were used. FACS was used for isolation of cancer stem cells using antibodies against CD44 and ALDH1. However we could not get specific response from CD44 antigen ie can not isolate cancer stem cell. However ALDH1 antibody selection gave us isolation of cancer stem cells from both of UTTSCC74A and B cell lines though much less cancer stem cells existed in UTTSCC74B cell line. The cells were first cultured in normal DMEM with 10% FBS under the condition of 5% CO2. Then the cells were changed into stem cell medium and cultured. Cancer stem cells were isolated using antibody against ALDH1 and these cells were cultured in stem cell medium and its characteristics were confirmed through sphere formation as well as immunofluorescence staining with antibody against ALDH1 and control antibody against DAPI. Expressions of sox-2, oct-4 and klf-4 were confirmed. After characterization of cancer stem cell from head and neck cancer cell line was confirmed, microarray analysis were performed using Gene Chip PrimeView Human expression Array (U133-HG133/ 47,000 transcript). Each group of ALDH1+ (cancer stem) and - cells isolated from each of UTTSCC74A and UTTSCC74B cell lines were exposed to microarray analysis. RNA extraction and cDNA construction from each sub group were prepared for microarray analysis. Comparison of UTTSCC74A ALDH1+ and - provided increased expression of 2037 and decreased expression in 2263 genes in various ratios. Similarly comparison of UTTSCC74B ALDH1+ and - provided increased expression of 6349 and decreased expression in 5322 genes in various ratios. 26 genes with most up and down regulation were selected and confirmation was done through real-time RT-PCR designing custom primers. Similar results were taken as in microarray analysis. From these 26 genes with confirmation of their expressions, 5 up regulated and 5 downregulated genes were selected for further analysis. We currently prepare expression plasmids of these genes and continue their in vitro functional analysis. Thus, the identification of the cancer-stem cell related signalling pathways in head and neck cancer stem cell would provide valuable information for a better understanding of cancer stem cell properties, molecular mechanisms of carcinogenesis, invasion and metastasis in this cancer type. By this way, effective therapeutic options targeting CSCs may be developed. Citation Format: Mehmet Gunduz, Omer Faruk Hatipoglu, Esra Gunduz, Elif Nihan Cetin, Eyyup Uctepe, Sadik Cigdem, Reidar Grenman, Muradiye Acar. Characterization of cancer stem cell properties and identification of invasion as well as metastatic process in head and neck cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1399. doi:10.1158/1538-7445.AM2015-1399

Breast Cancer Stem Cells and Cellomics

“Omics” technologies are powerful high-throughput analytic tools to get inside whole-system level alterations of cancer cells. Since cancer stem cells are groups of vital cells in heterogeneous tumor populations, their omics analysis will enable better understanding in most controversial issues. These issues are mostly treatment resistance and metastatic ability of tumors. The relation between breast cancer patients’ survival rates and stem cells in breast tumor has revealed the significance of breast cancer stem cells. The high tumor-forming capacity of these stem cells makes it necessary to get more comprehensive insight about their biology. Genomics, proteomics, and epigenomics are helpful tools for this purpose. The general step of these high-throughput methods is the isolation of breast cancer stem cells based on specific markers. Another shared feature of these omics approaches is to use a large set of interested genes, transcripts, or proteins. In addition to these two common key features, the remaining experimental setups may change from one to another omics analysis. The outcome of these approaches can yield some signatures, which will be mostly critical for later therapeutic strategies. Taken altogether, omics approaches not only reveal comprehensive understanding about breast cancer stem cells but also open the doors to more effective targeted therapies.

Omics of Male Breast Cancer

Male breast cancer (MBC) is rarely diagnosed. However, it has relatively poor prognosis when compared to female breast cancer. Although the importance of genetic predisposition in MBC etiology has been considerably understood, a wide range of gene and protein alterations playing various roles in MBC carcinogenesis point at its polygenic nature rather than single gene inheritance. Therefore, more comprehensive approaches including omics study and related technologies are required to thoroughly manage this malignancy, though such studies have been scarcely performed in MBC.

Oncogenes and Tumor Suppressor Genes as a Biomarker in Breast Cancer

Breast cancer is the most common cause of cancer in women in the United States and the Western world. The important question is what can be done to limit the human suffering associated with cancer and to reduce the burden on society? One solution is early detection. Early diagnosis of breast cancer before symptoms emerge is the most effective prevention of breast cancer.