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Endoplazmik Retikulum (ER) ökaryotik hücrelerde bulunan, hücre içi kalsiyum homoastasizi, lipid sentezi, proteinlerin işlenmesi ve katlanmasından sorumlu olan bir organeldir. Hatalı katlanmış veya katlanmamış proteinlerin artması durumunda ortaya çıkan hücresel cevap endoplazmik retikulum stresi olarak adlandırılır. Değişen çevre koşullarına adaptasyonu sağlamak amacıyla evrimsel süreçte korunmuş bir mekanizma olan Katlanmamış Protein Cevabı (UPR) ile uyum sağlanmaya çalışılmaktadır. Ancak endoplazmik retikulum stresi ile başa çıkılamadığı durumlarda apopitoz tetiği çekilerek hücre ölümü meydana gelmektedir. Endoplazmik retikulum stresinin indüklediği apopitoz yolağında; CCAAT/enhance binding protein (C/EBP) homolog protein (CHOP), Mitojen tarafından aktive edilmiş protein kinaz (MAP kinaz) kaskadı, Bcl-2-ilişkili X protein (Bax/Bak), İnozitol Gerektiren Kinaz 1 (IRE1) ve kaspaz-12 gibi birçok molekül görev almaktadır. Endoplazmik retikulum stresinin kanser hücresi proliferasyonu ve sağkalımı üzerinde büyük bir etkisi vardır. Son yapılan araştırmalar endoplazmik retikulum stresi ve katlanmamış protein cevabının, kanserde önemli rol oynadığını göstermiştir. Nitekim, tümör hücrelerinin büyümesinde ve çevresel değişikliklere adaptasyonda rol oynayan katlanmamış protein cevabının, genellikle kanser hücrelerinin lehine çalışan bir süreç olarak kullanıldığı bulunmuştur. Endoplazmik retikulum stresinin tetiklediği katlanmamış protein cevabında tam olarak aydınlatılamamış bazı mekanizmaların varlığı, tedaviye giden süreci olumsuz yönde etkilemekte olduğundan bu mekanizmaların tam olarak aydınlatılmasıyla birlikte; hastalıkların daha iyi anlaşılması ve yeni tedavi stratejilerinin geliştirilmesinin de önü açılacaktır. Bu derlemede; kanser hücrelerinin endoplazmik retikulum stres cevabı ile proliferasyonlarını nasıl sürdürebildikleri, katlanmamış protein cevabı ekseninde ele alınacak ve bunun altında yatan moleküler mekanizmalara genel bir bakış yapılacaktır.

Pancreatic ductal adenocarcinoma (PDAC) remains one of the deadliest cancers. Uncovering mechanisms responsible for the heterogeneous clinical features of this disease is an essential step toward developing improved and more specific therapeutic approaches. Here, we sought to identify transcriptional regulators of aggressive PDAC growth through in vivo CRISPR screening of epigenetic and transcription factors in an orthotopic model. We identified the ISL LIM homeobox 2 (ISL2) gene as a tumor suppressor whose depletion enhances the proliferation of human PDAC cells in vitro and in vivo and cooperates with activated KRAS to initiate PDAC in a murine model. Conversely, the upregulation of ISL2 expression through CRISPR-mediated locus-specific epigenetic editing results in reduced cell proliferation. Importantly, ISL2 is epigenetically silenced through DNA methylation in ~60% of PDAC tumors, which correlates with poor patient outcome. Functional studies showed that ISL2 loss rewires metabolic gene expression, and consequently potentiates oxidative phosphorylation while reducing glycolysis. This metabolic shift creates selective vulnerability to small molecule inhibitors of mitochondrial respiration and fatty acid oxidation. Collectively, these findings reveal ISL2 as a novel tumor suppressor whose inactivation drives metabolic reprogramming in an aggressive PDAC subset and point to potential therapeutic vulnerabilities in these tumors.

Diabetes mellitus is a metabolic disease that causes increased morbidity and mortality in developed and developing countries. With recent advancements in technology, alternative treatment methods have begun to be investigated in the world. This study aims to evaluate the effect of pulsed magnetic field (PMF) on vascular complications and contractile activities of aortic rings along with Kir6.1 and Kir6.2 subunit expressions of ATP-sensitive potassium channels (KATP) in aortas of controlled-diabetic and non-controlled diabetic rats. Controlled-diabetic and non-controlled diabetic adult male Wistar rats were exposed to PMF for a period of 6 weeks according to the PMF application protocol (1 h/day; intensity: 1.5 mT; consecutive frequency: 1, 10, 20, and 40 Hz). After PMF exposure, body weight and blood glucose levels were measured. Then, thoracic aorta tissue was extracted for relaxation–contraction and Kir6.1 and Kir6.2 expression experiments. Blood plasma glucose levels, body weight, and aortic ring contraction percentage decreased in controlled-diabetic rats but increased in non-controlled diabetic rats. PMF therapy repressed Kir6.1 mRNA expression in non-controlled diabetic rats but not in controlled diabetic rats. Conversely, Kir6.2 mRNA expressions were repressed both in controlled diabetic and non-controlled diabetic rats by PMF. Our findings suggest that the positive therapeutic effects of PMF may act through (KATP) subunits and may frequently occur in insulin-free conditions. Bioelectromagnetics. 2018;9999:XX–XX. © 2018 Wiley Periodicals, Inc.

Purpose: The aim of this study was to show the effects of nicotine on expression levels of SOX2 and SOX4 genes, which are known for their master gene features, in human amniotic cell cultures. The study also aimed to show the effects of resveratrol, an antioxidant, on expression levels of these genes in human amniotic cell cultures, which are treated by nicotine.Material and Methods: Twenty patients were included in this study and for each patient; control, nicotine treated and nicotine + resveratrol treated cell culture groups are formed. The expression levels of SOX2 and SOX4 genes are examined in each group by using real time RT-PCR.Results: Change in expression levels of SOX2 and SOX4 genes in nicotine treated group were found to be statistically significant. Also, when groups treated with nicotine and nicotine + resveratrol were compared the difference was found to be statistically significant.Conclusions: Nicotine increased the expression levels of SOX2 and SOX4 genes by 60% in human amniotic cell cultures and resveratrol was found to be an important antioxidant that reduces the increased expression levels of SOX2 and SOX4 genes caused by nicotine treatment., Amaç: Sigarada bulunan en önemli toksik bileşenlerden bir tanesi nikotindir. Prenatal dönemde sigara dumanına maruz kalmak yeni doğanda bilişsel, duygusal, davranışsal problemler ve çocukluk kanserleriyle birlikte birçok farklı problem ortaya çıkarabilmektedir. Bu çalışmada, nikotinin master gen özelliklerine sahip genlerden olan SOX2 ve SOX4 genlerinin ekspresyon düzeylerine etkilerinin insan amniyotik hücre kültüründe araştırılması amaçlanmıştır. Ek olarak, bir antioksidan olan resveratrolün nikotin ile muamele edilmiş hücrelerde bu genlerin ekspresyon düzeylerine etkileri insan amniyotik hücre kültüründe incelenmiştir.Yöntem: Çalışmaya 20 hasta dahil edilmiştir ve her hasta için kontrol, nikotin ve nikotin+resveratrol hücre kültürü grupları oluşturulmuştur. SOX2 ve SOX4 genlerinin ekspresyon düzeyleri her grup için real time RT-PCR yöntemi kullanılarak tespit edilmiştir.Bulgular: SOX2 ve SOX4 genleri için nikotin ile muamele edilen grupta tespit edilen ekspresyon düzeylerindeki değişim istatistiksel olarak anlamlı bulunmuştur (p= 0.005 SOX2, p=0.000 SOX4). Ayrıca, nikotin ve nikotin+resveratrol ile muamele edilmiş gruplar karşılaştırıldığında sonuç istatistiksel olarak anlamlı bulunmuştur.Sonuç: Nikotin, insan amniyotik hücrelerinde SOX2 ve SOX4 genlerinin ekspresyon düzeylerini %60 oranında artırmıştır ve resveratrolün bu artmış ekspresyon düzeylerini düşüren önemli bir antioksidan olduğu tespit edilmiştir.

Amaç: Fenilketonüri, hepatik bir enzim olan fenilalanin hidroksilazın otozomal resesif bozukluğu sonucu ortaya çıkan bir durumdur. Bu çalışmada, Türk popülasyonunda en sık görülen fenilalanin hidroksilaz geni mutasyonlarını belirlemek amaçlandı. Gereç ve Yöntem: Öncelikle tüm ekson bölgeleri DHPLC metodu kullanılarak tarandı. Ardından mutasyon şüphesi taşıyan örnekler sekanslama ve ARMS yöntemleri kullanılarak analiz edildi.Bulgular: IVS10-11ga splayzing mutasyonu 27 allelde (%58,7), R261Q mutasyonu 7 allelde (%15,2) ve E178G, P281L, R243X, R243Q, R408W, Y386C mutasyonları ise 2’şer allelde (%4,3) tespit edildi.Sonuç: R243X, R243Q, R261Q ve R408W mutasyonlarının oluştuğu 7 ve 12’inci ekson bölgelerinde arginin aminoasidinin değişimi Çukurova bölgesindeki fenilketonüri hastalarında fenilalanin hidroksilaz geni mutasyonlarında önemli bir yer tutmaktadır (%68,4). IVS10-11ga ve P281L gibi tek baz mutasyonları bizim tarafımızdan dizayn edilmiş primerler ve ARMS tekniği kullanılarak daha ucuza, daha az teknik ekipmanla ve %100 doğrulukla tespit edilebilmektedir., Purpose: Phenylketonuria is an autosomal recessive deficiency of the hepatic enzyme phenylalanine hydroxylase. With this study, detection of the most frequent phenylalanine hydroxylase gene mutations in Turkish population is aimed.Material and Methods: 23 unrelated phenylketonuria patients (46 alleles) who are living in Cukurova region, Turkey were investigated.First, all exons were screened by using DHPLC method then the direct sequencing technique and ARMS methods were used to analyze mutation suspected samples.Results: IVS10-11g®a splicing mutation in 27 alleles (58.7%), R261Q mutation in 7 alleles (15.2%) and E178G, P281L, R243X, R243Q, R408W, Y386C mutations, all in a frequency of 2/46 (4.3%) is found.Conclusion: The arginine amino acid, accounting for 68.4% of changes in exon sites 7 and 12, where R243X, R243Q, R261Q and R408W mutations occur, is thought to be important for amino acid changes in phenylalanine hydroxylase gene among phenylketonuria patients in Çukurova region. Single-base mutations like IVS10-11g®a and P281L could be detected with an accuracy of 100% by the use of specifically designed primers by authors according to ARMS technique and it is relatively cheaper and requesting less technical equipment.

Joubert syndrome (JS) is an autosomal recessive genetic disorder. To date, mutations in 20 genes of the genetically heterogeneous JS and JS-related disorders (JSRD) have been reported. Renal involvement occurs in 2-20% of JS cases. Identified renal abnormalities are cystic dysplasia and nephronophthisis. Here we report the clinical course and management of renal failure in early childhood. We present two cases diagnosed with JS that developed end-stage renal disease at young ages. In the genetic studies, a c.5668GT (p.G1890*) homozygous stop mutation was identified in the CEP290 gene of one of the patients and a c.1303CG (p.R435G) homozygous mutation in the INPP5E gene of the other. It has been emphasized that it is important to evaluate patients in terms of renal disease when monitoring the progress of Joubert syndrome, a condition that predominantly causes mental and motor development retardation.

Hearing loss (HL) is the most common sensory disorder, affecting all age groups, ethnicities, and genders. Several genes responsible for hearing loss are related to ion recycling and homeostasis in the inner ear. Mutations in GJB2 gene, the gene encoding gap junction protein connexin26 (Cx26), are most common detected in patients with congenital, recessively inherited, nonsyndromic HL in humans. In order to investigate the molecular etiology of patients with congenital, recessively inherited, and nonsyndromic HL and healthy individuals as control in a family, they were included in this study. Thus, exons of GJB2 gene were amplified by polymerase chain reaction (PCR) and sequenced. In this family, V27I missense mutation and V27I + E114G compound heterozygosity were detected in the results of sequence analysis. The V27I mutation was found in patient with severe HL and healthy individuals. The V27I + E114G compound heterozygosity was detected only in deaf patients. Based on our data, V27I mutations could be considered as a polymorphism not leading to HL. Since V27I + E114G compound heterozygosity was found only in deaf patients, it could be considered as a contributor of HL severity.

PubMedID: 24731844 Background To evaluate clinical, genetic, and radiologic features of our patients with muscle-eye-brain disease. Methods The data of patients who were diagnosed with muscle-eye-brain disease from a cohort of patients with congenital muscular dystrophy in the Division of Pediatric Neurology of Dokuz Eylül University School of Medicine and Gaziantep Children's Hospital between 2005 and 2013 were analyzed retrospectively. Results From a cohort of 34 patients with congenital muscular dystrophy, 12 patients from 10 families were diagnosed with muscle-eye-brain disease. The mean age of the patients was 9 ± 5.5 years (2-19 years). Mean serum creatine kinase value was 2485.80 ± 1308.54 IU/L (700-4267 IU/L). All patients presented with muscular hypotonia at birth followed by varying degrees of spasticity and exaggerated deep tendon reflexes in later stages of life. Three patients were able to walk. The most common ophthalmologic and radiologic abnormalities were cataracts, retinal detachment, periventricular white matter abnormalities, ventriculomegaly, pontocerebellar hypoplasia, and multiple cerebellar cysts. All of the patients had mutations in the POMGNT1 gene. The most common mutation detected in 66% of patients was c.1814 G > A (p.R605H). Two novel mutations were identified. Conclusions We suggest that muscle-eye-brain disease is a relatively common muscular dystrophy in Turkey. It should be suspected in patients with muscular hypotonia, increased creatine kinase, and structural eye and brain abnormalities. The c.1814 G > A mutation in exon 21 of the POMGNT1 gene is apparently a common mutation in the Turkish population. Individuals with this mutation show classical features of muscle-eye-brain disease, but others may exhibit a milder phenotype and retain the ability to walk independently. Congenital muscular dystrophy patients from Turkey carrying the clinical and radiologic features of muscle-eye-brain disease should be evaluated for mutations in POMGNT1 gene. © 2014 Elsevier Inc. All rights reserved.

Amaç: Normal ve streptozotosin ile indüklenen diyabetik sıçanlarda serum kolesterol, glikoz, ve trigliserid seviyelerinin normale dönmesini, damarsal hasarların giderilmesini ve özellikle aort halkalarında gevşeme yanıtının oluşmasında olumlu etkileri olan pulslu manyetik alanın (PMA) streptozotosin ile indüklenen diyabetik sıçanlarda ATP’ye duyarlı potasyum kanalları alt ünitelerinden olan Kir 6.1 ve Kir 6.2 üzerine olan etkilerini belirlemek bu çalışmamızın temel amacıdır. Yöntem: Diyabet, sıçanlarda Streptozotosin uygulaması ile indüklendi. Diyabetik sıçanlara 1,5 mT şiddetinde pulslu manyetik alan tedavisi uygulandı. Aortları kesilerek çıkarıldı ve mRNA izole edilerek ardından cDNA haline çevrildi. mRNA ekspresyon düzeylerini belirlemek için Kir 6.1 ve Kir 6.2 mRNA’larına özgü primerler aracılığıyla real time PCR yapıldı. Bulgular: Çalışmalarımızda kullanılan PMA’nın, diyabetik sıçanlarda Kir 6.1 mRNA ekspresyonunu baskılarken ve Kir 6.2 mRNA ekspresyonunu indüklediği gözlenmiştir. Sonuç: PMA tedavisi aortda diyabete bağlı olarak ortaya çıkan endotel hasarlar ile ilişkilendirilmiş kasılma-gevşeme yanıtı ve vasküler tonda oluşan fonksiyon bozukluklarının kısmen iyileştirilmesini sağlar. Bizim buradaki bulgularımız, PMA’nın pozitif tedavi edici etkisini ATP’ye duyarlı potasyum kanallarının üzerinden gerçekleştirdiğini önermektedir. Purpose: Our goal is to determine the effects of pulsed field magnetic field treatment (PMF), which has been reported to lower blood cholesterol, glucose, triglyceride levels and recover vascular defects of diabetic rats, on ATP-sensitive potassium channel subunits, Kir 6.1 and Kir 6.2, of streptozotocin (STZ)-induced diabetic rat aorta. Methods: Diabetes was induced in rats by streptozotocin administration. Pulsed filed magnetic field treatment performed at 1,5 mT intensity on diabetic rats. Aortas were excised out and mRNAs were isolated and reverse transcribed into cDNAs. In order to evaluate mRNA expression levels, real time PCR was employed with primers specific for Kir 6.1 and Kir 6.2 mRNA. Results: In our studies, pulsed filed magnetic field treatment repressed Kir 6.1 but not Kir 6.2 mRNA expression in diabetic rats. Conclusion: In aorta diabetes-induced endothelial dysfunction leads to impairment in contraction-relaxation response and vascular tone, which could be recovered in part by PMF treatment. Our findings here may suggest that the positive therapeutic effect of PMF possibly act through the regulation of ATP-sensitive potassium channels, Kir 6.1 and Kir 6.2.

BACKGROUND: To evaluate clinical, genetic, and radiologic features of our patients with muscle-eye-brain disease. METHODS: The data of patients who were diagnosed with muscle-eye-brain disease from a cohort of patients with congenital muscular dystrophy in the Division of Pediatric Neurology of Dokuz Eylul University School of Medicine and Gaziantep Children’s Hospital between 2005 and 2013 were analyzed retrospectively. RESULTS: From a cohort of 34 patients with congenital muscular dystrophy, 12 patients from 10 families were diagnosed with muscle-eyebrain disease. The mean age of the patients was 9 � 5.5 years (2-19 years). Mean serum creatine kinase value was 2485.80 � 1308.54 IU/L (700-4267 IU/L). All patients presented with muscular hypotonia at birth followed by varying degrees of spasticity and exaggerated deep tendon reflexes in later stages of life. Three patients were able to walk. The most common ophthalmologic and radiologic abnormalities were cataracts, retinal detachment, periventricular white matter abnormalities, ventriculomegaly, pontocerebellar hypoplasia, and multiple cerebellar cysts. All of the patients had mutations in the POMGNT1 gene. The most common mutation detected in 66% of patients was c.1814 G > A (p.R605H). Two novel mutations were identified. CONCLUSIONS: We suggest that muscle-eye-brain disease is a relatively common muscular dystrophy in Turkey. It should be suspected in patients with muscular hypotonia, increased creatine kinase, and structural eye and brain abnormalities. The c.1814 G > A mutation in exon 21 of the POMGNT1 gene is apparently a common mutation in the Turkish population. Individuals with this mutation show classical features of muscle-eye-brain disease, but others may exhibit a milder phenotype and retain the ability to walk independently. Congenital muscular dystrophy patients from Turkey carrying the clinical and radiologic features of muscle-eye-brain disease should be evaluated for mutations in POMGNT1 gene.