The comparison between dual inhibition of mTOR with MAPK and PI3K signaling pathways in KRAS mutant NSCLC cell lines

KRAS mutations are found in 15–25 % of patients with lung adenocarcinoma, and they lead to constitutive activation of KRAS signaling pathway that results in sustained cell proliferation. Currently, there are no direct anti-KRAS therapies available. Therefore, it is rational to target the downstream molecules of KRAS signaling pathway, which are mitogenactivated protein kinase (MAPK) signaling pathway (RAFMEK- ERK) and PI3K pathway (PI3K-AKT-mTOR). Here, we examined the inhibition of both these pathways alone and in combination and analyzed the anti-proliferative and apoptotic events in KRAS mutant NSCLC cell lines, A549 and Calu-1. Cytotoxicity was determined by MTT assay after the cells were treated with LY294002 (PI3K inhibitor), U0126 (MEK inhibitor), and RAD001 (mTOR inhibitor) for 24 and 48 h. The expression levels of p-ERK, ERK, AKT, p-AKT, p53, cyclinD1, cmyc, p27kip1, BAX, BIM, and GAPDH were detected by western blot after 6 and 24 h treatment. Although PI3K/mTOR inhibition is more effective in cytotoxicity in A549 and Calu-1 cells, MEK/mTOR inhibition markedly decreases cell proliferation protein marker expressions. Our data show that combined targeting of MEK and PI3K-AKTwith mTOR is a better option than single agents alone forKRASmutantNSCLC, thus opening the possibility of a beneficial treatment strategy in the future

Multifunctional Sox2 gene which turns out a new target in cancer

Sox2 proteini, farklılaşmamış erken embriyo kök hücrelerinin ve çeşitli yetişkin kök hücrelerinin gelişimi ve devamlılığının düzenlenmesinde rol oynayan bir transkripsiyon faktörüdür. Sox2, diğer pluripotensi faktörleri gibi post-transkripsiyonel ve post-translasyonel değişimlere uğramakta, böylece DNA’ya bağlanma aktivitesi değişebilmektedir. Sox2, kanser hücrelerinin çoğalması, invazyon, göç ve metastazında, tümör hücre ve kök hücre statüsünün devamında, hücresel programlama, apoptoz ve kemodirenç gelişimi gibi pek çok kanser aşamasında yer almaktadır. Bazı farklı bulgulara karşın çoğunlukla Sox2’nin kanser hücrelerinde anti-apoptotik bir faktör olarak çalıştığı konusunda uzlaşma vardır. Bu derlemede, Sox2’nin kök hücre devamlılığı, farklılaşması ve sinyal iletimindeki rollerini, bunun yanında gen çoğalmasıyla onkojenik özelliği kazanmasını ve moleküler hedef olarak kullanılma potansiyelini de kapsayan çok yönlü özelliklerini kısaca tartışacağız

APOPTOTIC EFFECT OF VINORELBINE ON HUMAN SERVICAL CANCER HeLa CELLS

Amaç: Hücre hareketi, hücre bölünmesi, hücre içi madde taşınması, hücresel yapınınsağlanması gibi biyolojik işlevlerde rol alan mikrotübüller, antikanser ilaçların esashedefi konumundadır. Vinorelbin'in (Navelbin) mikrotübüller üzerinden etki gösterenmoleküllerden birisidir ve çeşitli kanserlerde kemoterapötik ajan olarak kullanılmaktadır.Çalışmamızda, insan serviks kanser hücre hattı olan HeLa hücrelerine, 24saat 5-100μM doz aralığında vinorelbin uygulaması sonunda hücrelerdeki olasıapoptotik etkisini belirlemeyi amaçladık.Gereç ve yöntem: Vinorelbin uygulanan HeLa hücrelerinde hücre canlılığı ve apoptotikoranları belirlemek için sırasıyla XTT canlılık analizi ve floresan mikroskobundahücrelerin karakteristik morfolojisi değerlendirildi. Vinorelbin uygulanan hücrelerde Bhücresi lenfoma 2 (BCL2) ve Siklin D1 (CCND1) genlerinin mRNA ifade düzeyleri dearaştırıldı.Bulgular: En yüksek vinorelbin konsantrasyonu olan 100μM'da hücre canlılığının 24saat sonunda %60'ın altına düştüğü belirlendi. Apoptotik oranın %17,6 olduğu 40μMdozda aynı zamanda nekrotik oranın da 80 ve 100μM dozlara oranla oldukça az olmasısebebiyle en etkili apoptotik doz olarak 40μM bulundu. Ayrıca 40μM vinorelbinuygulamasının anti-apoptotik özellikteki BCL2 ile proto-onkogen olan CCND1genlerinin mRNA ifade edilme düzeylerinde azalmaya neden olduğu saptandı.Sonuç: Mikrotübül dinamiğini etkileyerek antikanser özellik gösteren vinorelbin'inmoleküler düzeyde olası etki mekanizmalarının belirlenmesinin, kanser tedavisindedaha etkin yaklaşımların ortaya çıkmasında yardımcı olabileceği kanısındayız.Objective: Microtubules, having roles in many biological functions including cellmotility, cell division, intracellular transport, cellular architecture, are major targets foranticancer drugs. Vinorelbine (Navelbin) is one of the molecules that affectsmicrotubules and used as a chemotherapoetic agent in various cancers. In our study,we aimed to determine prospective apoptotic effect of the vinorelbine on humanservical carcinoma cell line HeLa cells at 24 hours between 5-100μM dose incubation.Material and Method: For this purpose, vinorelbine treated HeLa cells, were assessedby XTT viability analysis and fluoresence microscopy to determine cell characteristicmorphology. B cell lyphoma 2 (BCL2) and cyclin D1 (CCND1) genes' mRNA expressionlevels were also evaluated in vinorelbine applied cells Results: Cell viability was found to be below 60% for the highest vinorelbineconcentration (100μM) at the end of 24 hours incubation. Apoptotic ratio was found17.6% for the 40μM dose at the same time necrotic ratio was found lower than 80 and100μM doses. Therefore, the most effective apoptotic dose was found to be 40μM.Moreover, we detected that 40μM vinorelbine treatment caused a decrease in antiapoptoticBCL2 and proto-oncogene CCND1 genes' expression levels.Conclusion: We believe that determination of molecular mechanisms involvingvinorelbine which has anticancer properties by virtue of distrupting microtubuledynamics, may lead to development of more effective approaches in cancer treatment

Hdac inhibitors, Ms-275 and salermide, potentiates the anticancer effect of ef24 in human pancreatic cancer cells

, Handan/0000-0003-4967-2740; YILMAZ, AKIN/0000-0002-4368-0777WOS: 000374213400002PubMed: 27330528Histone deacetylases (HDACs) play a major role in the regulation of chromatin structure and gene expression by changing acetylation status of histone and non-histone proteins. MS-275 (entinostat, MS) is a well-known benzamide-based HDACI and Salermide (SAL), a reverse amide compound HDACI, have antiproliferative effects on several human cancer cells. In this study, we aimed to investigate the effects of HDACIs (MS and SAL) alone and/or combined use with EF24 (EF), a novel synthetic curcumin analog, on human pancreatic cancer cell line (BxPC-3). In vitro, BxPC-3 cells were exposed to varying concentrations of MS, SAL with or without EF, and their effects on cell viability, acetylated Histone H3 and H4 levels, cytotoxicity, and cleaved caspase 3 levels, and cell cycle distribution were measured. The viability of BxPC-3 cells decreased significantly after treatment with EF, MS and SAL treatments. MS and SAL treatment increased the acetylation of histone H3 and H4 in a dose dependent manner. MS and SAL alone or combined with EF were increased the number of cells in G1 phase. In addition, treatment with agents significantly decreased the ratio of cell in G2/M phase. There were significant dose-dependent increases at cleaved Caspase 3 levels after MS treatment but not after SAL treatment. Our results showed that HDAC inhibitors (MS and SAL), when combined with EF, may effectively reduce pancreatic cancer cell (BxPC-3) progression and stop the cell cycle at G1 phase. Further molecular analyses are needed to understand the fundamental molecular consequences of HDAC inhibition in pancreas cancer cells.Gazi University Research FoundationGazi University [01/2010-39]This study is partially supported by Gazi University Research Foundation (Project code 01/2010-39)

Evaluation of Advanced Oxidation Protein Products, Prooxidant-Antioxidant Balance, and Total Antioxidant Capacity in Untreated Vitiligo Patients

BACKGROUND: Vitiligo is a chronic, common disease of unknown etiology, and oxidative stress is suggested to have a role in its etiopathogenesis. OBJECTIVE: Advanced oxidation protein products (AOPPs), prooxidant-antioxidant balance (PAB), and ferric-reducing antioxidant power (FRAP) were evaluated regarding their role in the pathogenesis of vitiligo as well as their relationship with clinical presentation and disease severity, and these parameters were compared with those of healthy controls. METHODS: The study included 53 patients with vitiligo and 20 healthy volunteers as the control group. AOPP level, PAB, and FRAP were determined by colorimetric methods. RESULTS: PAB and FRAP level were significantly higher in patients with vitiligo than in healthy controls (p<0.001). The AOPP levels in vitiligo patients were not statistically significantly higher than those in healthy controls. The Vitiligo Area Scoring Index positively correlated with disease duration (r(s): 0.531, p<0.001). CONCLUSION: To the best of our knowledge, this is the first report of AOPP and PAB status in vitiligo. PAB may be used as an indicator for oxidative stress in the etiopathogenesis of vitiligo. Our results show that these parameters may play a major role in the melanocyte damage observed in vitiligo. Further studies are required to confirm the mechanisms underlying this effect