Mustafa Ulasli

The association of the expression of miR-122-5p and its target ADAM10 with human breast cancer

MicroRNAs can regulate many biological functions. miR-122-5p has a tumor suppressor function through different molecular pathways. Also, our second hit, ADAM10, targeted by miR-122-5p, is a major determinant of HER2 shedding causing that trastuzumab cannot bind to HER2 receptors. Therefore, our analysis upon ADAM10 expression and miR-122-5p was a good point to understand molecular mechanism of breast cancer. In our study, we investigated the expression profiles of miR-122-5p and its target ADAM10 in 71 breast cancer patients. Immunohistochemical analysis of ER, PR and HER2 gene products was used to categorize tumors in patients. Expression data and immunohistochemical findings were evaluated to comment on the relationship between miR-122-5p and ADAM10. ADAM10 expression was higher in tumor than that of normal tissue but miR-122-5p expression was lower in tumor than that of normal tissue. The expression pattern in HER2+ patients was reverse of the overall result. It can be explained like that miR-122-5p expression increases especially in HER2+ cancer cell to suppress ADAM10 shedding activity on HER2 receptor. However, increase in expression of tumor suppressor miR-122-5p is not enough to inhibit ADAM10. All in all, we can think miR-122-5p as potential regulator of ADAM10 and trastuzumab resistance. Since if we increase miR-122-5p activity together with trastuzumab administration, then HER2+ breast cancer cells may overcome trastuzumab resistance by inhibiting ADAM10 shedding activity on HER2 receptors and increase the efficiency of trastuzumab.

Gene expression profiles of autophagy-related genes in multiple sclerosis

Multiple sclerosis (MS) is an imflammatory disease of central nervous system caused by genetic and environmental factors that remain largely unknown. Autophagy is the process of degradation and recycling of damaged cytoplasmic organelles, macromolecular aggregates, and long-lived proteins. Malfunction of autophagy contributes to the pathogenesis of neurological diseases, and autophagy genes may modulate the T cell survival. We aimed to examine the expression levels of autophagy-related genes. The blood samples of 95 unrelated patients (aged 17-65years, 37 male, 58 female) diagnosed as MS and 95 healthy controls were used to extract the RNA samples. After conversion to single stranded cDNA using polyT priming: the targeted genes were pre-amplified, and 96×78 (samples×primers) qRT-PCR reactions were performed for each primer pair on each sample on a 96.96 array of Fluidigm BioMark™. Compared to age- and sex-matched controls, gene expression levels of ATG16L2, ATG9A, BCL2, FAS, GAA, HGS, PIK3R1, RAB24, RGS19, ULK1, FOXO1, HTT were significantly altered (false discovery rate<0.05). Thus, altered expression levels of several autophagy related genes may affect protein levels, which in turn would influence the activity of autophagy, or most probably, those genes might be acting independent of autophagy and contributing to MS pathogenesis as risk factors. The indeterminate genetic causes leading to alterations in gene expressions require further analysis.

MicroRNA 603 acts as a tumor suppressor and inhibits triple-negative breast cancer tumorigenesis by targeting elongation factor 2 kinase

Triple negative breast cancer (TNBC) is an aggressive type of breast cancer characterized by the absence of defined molecular targets, including estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2) and is associated with high rates of relapse and distant metastasis despite surgery and adjuvant chemotherapy. The lack of effective targeted therapies for TNBC represents an unmet therapeutic challenge. Eukaryotic elongation factor 2 kinase (eEF2K) is an atypical calcium/calmodulin-dependent serine/threonine kinase that promotes TNBC tumorigenesis, progression, and drug resistance, representing a potential novel molecular target. However, the mechanisms regulating eEF2K expression are unknown. Here, we report that eEF2K protein expression is highly up-regulated in TNBC cells and patient tumors and it is associated with poor patient survival and clinical outcome. We found that loss/reduced expression of miR-603 leads to eEF2K overexpression in TNBC cell lines. Its expression results in inhibition of eEF2K by directly targeting the 3-UTR and the inhibition of tumor cell growth, migration and invasion in TNBC. In vivo therapeutic gene delivery of miR-603 into TNBC xenograft mouse models by systemic administration of miR-603-nanoparticles led to a significant inhibition of eEF2K expression and tumor growth, which was associated with decreased activity of the downstream targets of eEF2K, including Src, Akt, cyclin D1 and c-myc. Our findings suggest that miR-603 functions as a tumor suppressor and loss of miR-603 expression leads to increase in eEF2K expression and contributes to the growth, invasion, and progression of TNBC. Taken together, our data suggest that miR-603-based gene therapy is a potential strategy against TNBC.

Correlation between Rho-kinase pathway gene expressions and development and progression of glioblastoma multiforme.

Glioblastoma multiforme (GBM) is the most common and the most aggressive primary malignant tumor of the brain. Prognostic factors in GBM can be sorted as age, tumor localization, tumor diameter, symptom period and type, the extent of surgery, postoperative tumor volume, and adjuvant radiotherapy and/or chemotherapy status. Besides the interactions between actin microfilaments, microtubules, and intermediate filaments, environmental factors and intracellular signals which regulate them affect the cell invasion. Rho proteins and therefore Rho-kinase activation play important role at these changes. The aim of this study is to evaluate the relationship between the Rho-kinase pathway gene expressions and prognosis in GBM. Ninety-eight patients diagnosed as GBM between 2001 and 2010 were enrolled into the study. RNA was obtained from the paraffinized tumor tissue of the patients with formalin-fixed, paraffin-embedded RNA isolation kit and the mRNA expressions of 26 genes were investigated. There was a statistically significant negative correlation between the ages at the diagnosis and survival. There was a significant relationship between the overexpression of Rho-kinase pathway-related genes LIMK1, CFL1, CFL2, and BCL2 and low expression of MAPK1 gene and the survival of the patients. These results demonstrate for the first time that there is a marked contribution of Rho-kinase pathway-related genes to the progression and survival of the GBM. The expression of these genes may be related to response of multimodal therapy or these parameters could be used to determine possible unresponsive patients before treatment.

Synthesis, molecular modeling, and biological evaluation of novel chiral thiosemicarbazone derivatives as potent anticancer agents.

A series of new chiral thiosemicarbazones derived from homochiral amines in both enantiomeric forms were synthesized and evaluated for their in vitro antiproliferative activity against A549 (human alveolar adenocarcinoma), MCF-7 (human breast adenocarcinoma), HeLa (human cervical adenocarcinoma), and HGC-27 (human stomach carcinoma) cell lines. Some of compounds showed inhibitory activities on the growth of cancer cell lines. Especially, compound exhibited the most potent activity (IC50 4.6 μM) against HGC-27 as compared with the reference compound, sindaxel (IC50 10.3 μM), and could be used as a lead compound to search new chiral thiosemicarbazone derivatives as antiproliferative agents.

Polymorphism of CYP3A4 and ABCB1 genes increase the risk of neuropathy in breast cancer patients treated with paclitaxel and docetaxel

Background Interindividual variability of pharmacogenetics may account for unpredictable neurotoxicities of taxanes. Methods From March 2011 to June 2015, female patients with operable breast cancer who had received docetaxel- or paclitaxel-containing adjuvant chemotherapy were included in this study. All patients were treated with single-agent paclitaxel intravenously (IV) 175 mg/m2 every 3 weeks for four cycles, or IV 80 mg/m2 weekly for 12 cycles, and IV 100 mg/m2 docetaxel for four cycles as adjuvant treatment. We evaluated the relationship between neurotoxicity of taxanes and single-nucleotide polymorphisms of ABCB1, CYP3A4, ERCC1, ERCC2, FGFR4, TP53, ERBB2, and CYP2C8 genes. Taxane-induced neurotoxicity during the treatment was evaluated according to the National Cancer Institute Common Toxicity Criteria version 4.03 prior to each cycle. Chi-squared tests were used to compare the two groups, and multivariate binary logistic regression models were used for determining possible risk factors of neuropathy. Results Pharmacogenetic analysis was performed in 219 females. ABCB1 3435 TT genotype had significantly higher risk for grade ≥2 neurotoxicity (odds ratio [OR]: 2.759, 95% confidence interval [CI]: 1.172–6.493, P: 0.017) compared to TC and CC genotype, and also CYP3A4 392 AA and AG genotype had significantly higher risk for grade ≥2 neurotoxicity (OR: 2.259, 95% CI: 1.033–4.941, P: 0.038) compared to GG genotype. For FDGF4 gene with AG and GG genotype, OR was 1.879 (95% CI: 1.001–3.525, P: 0.048) compared to AA genotype with regard to any grade of neuropathy risk. We could not find any other association of other genotypes with neurotoxicity grades. Conclusion ABCB1 3435 TT genotype and CYP3A4 392 AA/AG genotypes may be used as predictors of neurotoxicity during taxane chemotherapy.

Do fasudil and Y-27632 affect the level of transient receptor potential (TRP) gene expressions in breast cancer cell lines?

Breast cancer (BC) is the most frequent cancer type in women, and the mortality rate is high especially in metastatic disease. Ion channels such as the transient receptor potential (TRP) channels correlate with malignant growth and cancer progression. Hence, some authors have suggested that the expression levels of TRP channels may be used as a marker in the diagnosis and predicting the prognosis of BC. Also, in some recent studies, targeting TRP channels are suggested as a novel treatment strategy in BC. The aim of this study was to investigate the effect of two Rho-kinase (ROCK) inhibitors, fasudil and Y-27632, on the expression levels of TRP channel genes in breast cancer cell lines (ZR-75-1, MCF7, and MDA-MB-231) and breast epithelial cell line (hTERT-HME1). The expression levels of TRP genes were determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR). We found that fasudil had reduced the TRPC1, TRPV2 expression levels in the ZR-75-1, MCF7, and MDA-MB-231 cell lines. On the other hand, fasudil and Y-27632 had reduced TRPM6 expression levels in all cell lines. Y-27632 increased the expression levels of TRPC7 in all cell lines. In conclusion, this is the first study demonstrating that the inhibition of ROCK pathway changes the expression levels of some TRP genes. Also, our study has firstly shown that the expression levels of the TRP genes which are suggested as a diagnostic and prognostic biomarker in BC, were changed with the treatment of fasudil and Y-27632.

Thr21Met (T21M) but not Ser89Asn (S89N) polymorphisms of the urotensin-II (UTS-II) gene are associated with Behcet's disease (BD).

Behcets disease (BD) is multisytemic vasculitis or chronic inflammation that may lead to various autoimmune and autoinflammatory syndromes. Exact etiopathogenesis of BD has not been clarified yet. Urotensin II (UTS-II) is predominantly a vasoactive peptide and Thr21Met polymorphism in UTS-II gene was proved to increasing in some autoimmune diseases. Considering these, our objective was to evaluate whether two UTS-II gene polymorphisms (Thr21Met and Ser89Asn) were responsible in genetic susceptibility to BD in a Turkish population. A total of 198 patients with BD and 275 healthy controls were enrolled. We analyzed the genotype and allele frequencies of two UTS-II gene polymorphisms, Thr21Met and Ser89Asn, in BD patients and in controls. We found that Thr21Met but not Ser89Asn polymorphisms of the UTS-II gene were markedly associated with the risk of developing BD (p<0.0001), The Met21Met genotype was less common among BD patients (6.1% in patients vs. 17.1% in controls; p<0.0001). There was also an increase in the 21Thr allele (54.8% in BD patients vs. 43.8% in controls) and a decrease in 21Met allele frequencies (45.2% in controls vs. 56.2% in patients) in the BD groups (p<0.0044). To the best of our knowledge, for the first time in the literature, our study claims that there is an association between Thr21Met, and not between Ser89Asn polymorphisms in the UTS-II gene and BD. These results put a new player to the field of undiscovered pathogenesis of BD and hopefully provide new insights to the treatment options.

Polymorphisms in the MTHFR gene are associated with recurrence risk in lymph node-positive breast cancer patients

Purpose The aim of this study is to clarify the relationship between recurrence risk of breast cancer and methylenetetrahydrofolate reductase (MTHFR) C677T polymorphisms. Patients and methods Breast cancer patients who had undergone surgery in Gaziantep University Oncology Hospital between June 2005 and June 2012 were followed-up and retrospectively enrolled in this study. Blood samples were collected from all patients to assess MTHFR C677T polymorphisms. Stage according to tumor–node–metastasis system, estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2 status, grade of disease, menopausal status, and administered chemotherapy or hormonal therapy were recorded. Effects of these parameters on recurrence risk were evaluated using univariate analysis and multivariate binary logistic regression model. Results Association of MTHFR C677T polymorphisms with recurrence risk was evaluated in 298 patients whose median age was 47 years (range: 21–79 years). In all patients, age (odds ratio [OR] =0.953, P=0.005) and N3 lymph node status (OR =6.293, P=0.001) were found to affect the recurrence risk. While MTHFR homozygote genotype did not have an effect on recurrence risk in all patients, increased risk was observed in lymph node-positive subgroup (OR =4.271; 95% CI 1.515–12.023; P=0.006). Adjusting for age, tumor size (T), and node status (N), MTHFR homozygote genotype had more statistically significant risk for recurrence (OR =3.255; 95% CI 1.047–10.125; P=0.041). Conclusion MTHFR TT genotype was found to be associated with increased recurrence risk in patients with lymph node-positive breast cancer.

Replication of coronavirus

Coronaviruses (CoVs) are a diverse family of viruses that interact at multiple levels with components of host cells taking this advantage of some of the cellular machineries for replication and proliferation. A lot is known about the molecular biology of CoVs but more information needs to be learned because no effective treatments against these viruses are available. The challenge now is to incorporate advance techniques in the investigative efforts done to understand further the biology of CoVs. In terms of molecular biology, mouse hepatitis virus (MHV) is the best-studied CoVs, and it is consequently considered a model system for the family of Coronaviridae. This review described replication, transcription, and assembly of CoVs.