Volume 43, Issue 2

Background Poly(ADP-ribosyl)ation (PARylation) catalyzed mainly by PARP1 is a highly regulated posttranslational modification associated with several pathways in cellular physiology and genotoxic deoxyribonucleic acid (DNA) damage response. PAR polymers and PARP enzyme function in DNA integrity maintenance and several PARP inhibitors have entered clinical phase studies for cancer therapies. Material and methods The effect of bosutinib, a dual Src/Abl kinase inhibitor, on PARylation was fluorometrically measured. The cytotoxic and chemosensitizing effects were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The levels of DNA repair proteins and PARP enzyme were examined by immunoblotting. Results In this study, bosutinib is characterized as a novel PARP inhibitor. Bosutinib inhibited oxidative stress-induced cellular PARylation and nuclear foci formation by downregulating PARP1 levels. Bosutinib was found to be more cytotoxic on Capan1 cells with BRCA2 mutation. Furthermore by acting as a chemosensitizer, bosutinib enhanced the cytotoxicity of doxorubicin (DOXO) and etoposide (ETP) by decreasing phosphorylation of DNA repair enzymes checkpoint kinase 1 (Chk1) and ataxia-telangiectasia mutated (ATM). Conclusion By inhibition of both PARP and DNA damage checkpoint kinases, bosutinib increased the phospho-H2AX levels, an early indicator of DNA double strand breaks.

Objectives This study investigated the effects of chromium chloride (CrCl 3 ·6H 2 O), chromium picolinate (CrPic) and picolinic acid on malondialdehyde (MDA), 8-hidroksi-2′-deoksiguanosine (8-OHdG) and genome damage in rabbits. Material and methods Forty, New Zealand rabbits were equally assigned to four groups which received either distilled water or 20 mg/day Cr (CrC1 3 ·6H 2 0), 200 μg/day CrPic and 1400 μg/day picolinic acid for 50 days. On the 25th and 50th days, MDA and 8-OHdG levels and the apoptotic-necrotic cells, micronucleus (MN), micronuclear buds (NBUD) and nucleoplasmic bridges (NPB) frequencies and on the 50th day, serum Cr and liver MDA levels were determined. Results CrPic increased live weight and feed consumption. On the 25th day of treatment, decreases were detected in MDA levels and MN, NPK and NBUD frequencies in CrPic and picolinic acid groups, and in 8-OHdG levels in CrCl 3 ·6H 2 O and CrPic groups. Slight or significant differences were determined in all investigated parameters between the measurements of on days 25 and 50. Conclusion Improvements in of MDA and 8-OHdG levels and genome damage indicators due to CrPic and picolinic acid on the 25th day of the treatment may show that short term of CrPic supplementation reduces oxidative and chromosomal DNA damage in rabbits.

Objectives To investigate the effects of glucagon-like peptide-1 (GLP-1) for the apoptosis of human umbilical vein endothelial cells (HUVECs) in high glucose and the related mechanisms. Material and methods HUVECs were cultured under different conditions for 48 h. The apoptosis rate of cells was detected by flow cytometry, the expression of p-Akt and p-eNOS was measured by Western blot, and the production of nitric oxide (NO) was detected by NO assay kit. Results HUVECs were incubated in high glucose, the apoptosis rate of cells increased, the expression of p-Akt and p-eNOS reduced, and the production of NO decreased. After GLP-1 was added into the high glucose, the apoptosis rate of cells significantly reduced, the expression of p-Akt and p-eNOS and the production of NO obviously increased. After exendin, wortmannine and L-NAME were added into high glucose and GLP-1, respectively, exendin, wortmannine and L-NAME increased the cell apoptosis, down-regulated the expression of p-Akt and p-eNOS and dropped the production of NO, except that L-NAME made no difference on the expression of p-Akt. Conclusion GLP-1 increased the expression of Akt and endothelial nitric oxide synthase (eNOS) in HUVECs via the up-regulation of PI3K/Akt/eNOS pathway and decreased the apoptosis rate of HUVECs in high glucose.

Objectives We aimed to investigate the potential use of the expression of apoptotic signaling pathway genes of rat in skin wound age estimation. Material and methods For this purpose, we formed cutting tool injuries using a scalpel in an experimental model. Then, we assessed Caspase 3, 8 and 9 mRNA levels by using quantitative real-time PCR and protein levels by using immunohistochemistry in rat skin wounds. In addition, we used TUNEL assay to detect apoptotic cells. Results We observed that Caspase 3 mRNA level significantly increased (2.1±0.4 folds) on day 3 (p<0.05) and Caspase 8 mRNA level significantly increased (1.8±0.2 folds) on day 5 (p<0.05). Caspase 9 mRNA level increased (1.9±0.1 folds) on day 3 and (2.5±0.4 folds) on day 5 (p<0.05). The percentage values of polymorphonuclear leukocytes (PMNLs) and inflammatory mononuclear cells (IMCs) were observed after immunohistochemical staining by Caspase 3, 8, 9 antibodies. Our immunohistochemistry results were found to be consistent with the mRNA results observed. We reported a statistically significant increase in Caspase 3, 8 and 9-positive cells on days 3 and 5 after immunohistochemical staining as well. Conclusion Our results suggest that time-dependent features of apoptotic factors might offer a potential tool in estimating wound age.

Objectives Our aim was to determine how well immunohistochemical analysis identified colon cancer patients with microsatellite instability in Turkish patients. Material and methods Subjects were patients that underwent surgery for colorectal cancer in our institution between 2006 and 2011. Patients were grouped as: (1) suspected Lynch syndrome (n=14), (2) familial colorectal cancer (n=14), and (3) sporadic colorectal cancer groups (n=14). Mismatch repair proteins were analyzed by a four antibody-panel immunohistochemistry. Microsatellite instability analysis was conducted on DNA samples using MSI-PCR followed by fragment analysis. Results The immunohistochemistry and PCR results had good concordance in 35/42 patients. Both microsatellite instability and at least one mismatch repair protein deficiency were detected in 11 patients, and both microsatellite stability and normal expression of mismatch repair proteins were detected in 24 patients. Test results were discordant in seven of the patients. Conclusion As it is not feasible to perform expensive molecular tests in healthcare units in many developing countries, the four antibody-panel immunohistochemistry is a reliable and affordable method for screening for colorectal cancer, including Lynch syndrome and sporadic cases when suspected.

Background The Non-recombining region of the Y-chromosome (NRY) is transferred from father to son in an unchanged form without recombination in meiosis. Since Short tandem repeats on Y-chromosome (Y-STRs) in this region do not have any recombination, these regions are identical in all male individuals who are related to the father except for mutations. Therefore, these regions gain importance in identification for the forensic sciences or determination of paternity. In determination of paternity, if mismatches are observed between father and child, population-specific mutation rates should be used to determine whether it is a mutation or a true exclusion. Therefore in this study, we aim to determine the mutation rates of 17 Y-STR loci in Turkey. Material and methods 17 Y-STR loci were typed by using AmpFlSTR ® Yfiler™ Kit in 90 volunteer father-son pairs. Mutation rates were calculated and compared with other populations. Results The mutations were found between three father-son pairs at DYS439 and DYS458 loci. In addition, a duplication in DYS389 II loci* 30, 31 was observed. The average mutation rate was determined as 1.96×10 −3 for Turkish population. Conclusion This investigation will contribute to minimize the possibility of false exclusion of the father-son and kinship relations.

Objectives Cancer is one of the leading causes of death throughout the world. Current therapy options suffer from the major limitations of side effects and drug resistance. Thus, continuing search for newer and safer anticancer drugs remains critically important. From this point of view, in the present study benzimidazole-hydrazone derivatives were synthesized by aiming at the identification of new chemical entities as potent anticancer agents. Material and methods A series of 12 new compounds of 4-(5(6)-substituted-1 H -benzimidazol-2-yl)- N′ thiophen/furan-2-yl-methylene) benzohydrazide derivatives were synthesized. The structures of the obtained compounds were elucidated using by IR, 1 H NMR, 13 C NMR, mass spectroscopy and elemental analyses. In vitro cytotoxic activity of the compounds against A549, MCF-7 and NIH/3T3 cell lines was evaluated by MTT assay. Results Among the tested compounds, compound 3e showed higher cytotoxicity against MCF-7 human breast cancer cells when compared with cisplatin. Also, it has lower cytotoxicty against healthy cell line, NIH/3T3. Conclusions It was determined that compound 3e showed inhibition towards MCF-7. Considering the substituent effect on cytotoxic activity, compound 3e bearing 2-methylthiophene has attracted attention with its higher anticancer activities.

Objective Chemoradiotherapy (CRT) is a commonly used therapeutic modality. We investigated CRT effects on acute phase reactants (APRs). The aim of this study was to assess possible changes in APR levels during radiotherapy and to determine the usefulness of APRs as prognostic factors in patients with non-small cell lung cancer (NSCLC) and glioblastoma multiforme (GBM). Methods We prospectively evaluated 30 patients and 30 healthy controls. Plasma levels of APRs were measured. Post-CRT and pre-CRT levels were compared. Survival of patients were also followed up for a period of 3 years. Results In NSCLC patients, post-CRT albumin, transferrin (Trf), and ceruloplasmin (Cp) levels were significantly lower, and post-CRT ferritin (FER) levels were significantly higher, than their pre-CRT levels. In GBM patients, post-CRT Trf and prealbumin (Prealb) levels were significantly higher than pre-CRT levels. Pre-CRT C-reactive protein (CRP) and FER levels in NSCLC patients and Cp levels in GBM patients were associated with patient survival. Conclusion This study suggests that APRs may be useful for monitoring response to treatment during CRT in NSCLC and GBM patients. Bearing in mind their accessibility and clinical value, plasma CRP and FER in NSCLC patients and Cp in GBM patients can be considered candidate prognostic factors.

Objectives DNA repair mechanisms work insufficiently in T2DM patients and hyperglycemia seen in diabetes disturbs the oxidant-antioxidant balance thus cause oxidative damage on DNA. The effects of the DNA repair genes’ have not yet been investigated on diabetes. The aim of this study was to investigate the association between APE1 Asp148Glu and XPG Asp1104His polymorphisms with T2DM in the Turkish population. Material and methods Sixty-five T2DM patients and 54 healthy individuals were included to this study as control. The polymerase chain reaction-restriction fragment length polymorphism techniques were used. Results When the study groups were compared, serum HDL-cholesterol levels were found statistically elevated in the controls. Once the APE1 Asp148Glu polymorphism distribution between the patient and control groups was investigated, the Glu/Glu genotype ratio was found significantly higher in the control group. Furthermore, the Asp/Glu genotype and the Asp allele prevalences were observed to be higher in the patient group. Also, patients with the Asp/Asp genotype had higher serum HDL-cholesterol levels than the others. Conclusion Despite the small number of subjects included, it could be interpreted that the Glu allele of the APE1 Asp148Glu polymorphism might be protective against and the Asp allele may be contributing to the development of diabetes.

Objectives To determine the effect of royal jelly (RJ) on the oxidant-antioxidant balance in rats with N-methyl-N-nitrosourea (MNU) induced breast cancer and to compare this with the chemotherapeutic agent paclitaxel. Material and methods Fifty-six female Sprague Dawley rats were divided into five groups. Except control group (n=8, Group I) others received MNU (50 mg/kg, a single dose, i.p.) to develop breast cancer: Group II (n=8) untreated, Group III (n=7) treated with paclitaxel (15 mg/kg/week, 3 times, i.p.), Group IV (n=7) with RJ (by oral gavage, 100 mg/kg/day, for 30 days), and Group V (n=7), with paclitaxel+RJ. At the end of 30 days, histopathological and biochemical parameters were evaluated in breast tissues. Results Levels of protein carbonyl (PC) and 8-hydroxy-deoxyguanosine (8-OHdG) were higher in Group V than in Group II while malondialdehyde (MDA) levels were lower in groups IV and V compared to Group II (p<0.05). Levels of catalase (CAT) in Group V and glutathione (GSH) in Group III were higher than Group II (p<0.05). Glutathione peroxidase (GPx) and superoxide dismutase (SOD) levels did not significantly different. Decreasing effect of RJ on CA15-3 levels was relevant to histopathological results. Conclusion Although RJ (with or without paclitaxel) had increasing effect of antioxidant status it was insufficient to reduce oxidative stress in breast cancer.

Objectives The association between manganese superoxide dismutase (MnSOD) p.Val16Ala polymorphism and cancer has been shown in various studies. The aim of this study is to investigate the relationship between MnSOD polymorphism (V/V, V/A, A/A) and cancer in the Turkish and Cypriot population through meta-analysis. Material and methods The present study included meta-analysis of 14 publications covering 2413 cancer patients and 2907 healthy control groups from 2005 to 2016. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using the random effect model of DerSimonian and Laird for each study. Publication bias was checked with funnel plot by Begg’s and Egger’s test statistics. Results Meta-analysis of MnSOD polymorphism was performed in the additive model (AV vs. VV; OR=1.133, 95% CI: 1.002–1.282), allele contrast (A vs. V; OR=1.016, 95% CI: 0.930–1.278), homozygote model (AA vs. VV; OR=0.983, 95% CI: 0.839–1.153), dominant model (AA+AV vs. VV; OR=1.090, 95% CI: 0.971–1.223) and recessive model (AA vs. AV+VV; OR=0.924, 95% CI: 0.803–1.064). The A/V genotype polymorphism was found be significant for cancer. Conclusion The frequency of the A/V heterozygote genotype of the MnSOD polymorphisms is found to be higher in the Cypriot and Turkish populations than any other genotype.

Background Resveratrol is a natural anti-carcinogenic polyphenol. Malignant pleural mesothelioma (MPM) is an aggressive tumor with poor prognosis. In this study, we investigated the effects of resveratrol on epithelioid MPM. Material and methods Human epithelioid MPM cell line (NCI-H2452) was exposed to resveratrol (5–200 μM) for 24 or 48 h. Cell viability was assessed by WST-1 assay. Flow cytometry analyses were performed to evaluate the effects of resveratrol on cell cycle distribution and apoptosis. Western blot analysis was used to determine protein expression levels of antioxidant enzymes, cyclin D1 and p53. Reactive oxygen species (ROS) were measured using H 2 DCFDA. Results Resveratrol reduced cell viability of the cells in a concentration and time dependent manner. After treatment, the cells accumulated in G0/G1 phase and the percentage of cells in G2/M phase was reduced. Resveratrol decreased cyclin D1 and increased p53 expression in cell lysates. Treated cells exhibited increased apoptotic activity. ROS were elevated with resveratrol treatment, but there was no change in the expression of superoxide dismutase (SOD)-1, SOD-2 and glutathione peroxidase. Conclusion Our results revealed that resveratrol exhibits anti-cell viability effect on epithelioid MPM cells by inducing cell cycle arrest and apoptosis. Resveratrol may become a potential therapeutic agent for epithelioid MPM.