A Panel of Circulating microRNAs as a Potential Biomarker for the Early Detection of Gastric Cancer.

Background: The high mortality rate of Gastric Cancer (GC) is a consequence of delayed diagnosis. The early diagnosis of GC could increase the five-year survival rate among patients. We aimed to find a panel of microRNAs (miRNA) for the detection of GC in the early stages. Methods: In this case-control study, we selected consistently upregulated miRNAs from the results of 12 high-throughput miRNA profiling studies in GC. In the profiling phase, the differential expressions of 13 candidate miRNAs were analyzed by quantitative reverse-transcription PCR (qRT-PCR) in two pooled RNA samples prepared from the plasma of eight GC patients and eight matched controls. In the validation phase, significantly upregulated miRNAs from the profiling phase were further evaluated in the plasma samples of 97 patients with stage I-IV gastric adenocarcinoma and 100 healthy controls. Results: In the profiling phase, six miRNAs (miR-18a, 21, 25, 92a, 125b and 221) were significantly upregulated in the GC patients compared to the controls (p<0.05). However, in the validation phase, only significant up-regulation of miR-18a, 21 and 125b was confirmed (p<0.05). A panel of miR-18a/21/125b was able to detect GC patients with stage I-IV from the controls (p<0.001; AUC=0.92, sensitivity=86%; specificity=85%). In addition, the panel could distinguish the early-stage GC (I+II) from the control group with an AUC of 0.83, a sensitivity of 83%, and a specificity of 75%. Conclusion: A panel of circulating miR18a/21/125b could be suggested as a potential biomarker for the early detection of GC.

Blockade of Nuclear Factor-Κb (NF-Κb) Pathway Using Bay 11-7082 Enhances Arsenic Trioxide-Induced Antiproliferative Activity in U87 Glioblastoma Cells.

Background: Glioblastoma (GBM), the most aggressive and common form of glioma, accounts for over 13,000 death per year in the United States which indicates the importance of developing novel strategies for the treatment of this fatal malignancy. Although Arsenic trioxide (ATO) hinders the growth and survival of GBM cells, the requirement of concentrations higher than 4 µM for triggering apoptotic cell death has questioned its safety profile. Since the NF-κB signaling pathway plays a crucial role in tumorigenesis and chemo-resistance, targeting this oncogenic pathway may sensitize GBM cells to lower concentrations of ATO. Methods: Anti-tumor effects of ATO as monotherapy and in combination with Bay 11-7082 were determined using MTT, crystal violet staining, Annexin V/PI staining and scratch assays. Quantitative reverse transcription-PCR (qRT-PCR) analysis was applied to elucidate the molecular mechanisms underlying the anti-tumor activity of this combination therapy. Results: Our results revealed that ATO and Bay 11-7082 synergistically inhibited the proliferation and survival of GBM cells. Also, it was revealed that NF-κB inhibition using Bay 11-7082 enhanced the inhibitory effects of ATO on migration of GBM cells via suppressing the expression of NF-κB target genes such as TWIST, MMP2, ICAM-1, and cathepsin B. Furthermore, combination treatment of GBM cells with ATO and Bay 11-7082 significantly induce apoptotic cell death coupled with downregulation of NF-κB anti-apoptotic target genes including Bcl-2 and IAP family members. Conclusion: Altogether, these findings suggest that combination therapy with ATO and Bay 11-7082 may be a promising strategy for the treatment of GBM.

Methylation Analysis of P16, RASSF1A, RPRM, and RUNX3 in Circulating Cell-Free DNA for Detection of Gastric Cancer: A Validation Study.

BACKGROUND: Most of Gastric Cancer (GC) patients are diagnosed at an advanced stage with poor prognosis. Hypermethylations of several tumor suppressor genes in cell-free DNA of GC patients have been previously reported. In this study, an attempt was made to investigate the methylation status of P16, RASSF1A, RPRM, and RUNX3 and their potentials for early diagnosis of GC. METHODS: Methylation status of the four tumor suppressor genes in 96 plasma samples from histopathologically confirmed gastric adenocarcinoma patients (Stage I-IV) and 88 healthy controls was determined using methylation-specific PCR method. Receiver operating characteristic curve analysis was performed and Area Under the Curve (AUC) was calculated. Two tailed p<0.05 were considered statistically significant. RESULTS: Methylated P16, RASSF1A, RPRM, and RUNX3 were significantly higher in the GC patients (41.7, 33.3, 66.7, and 58.3%) compared to the controls (15.9, 0.0, 6.8, and 4.5%), respectively (p<0.001). Stratification of patients showed that RPRM (AUC: 0.70, Sensitivity: 0.47, Specificity: 0.93, and p<0.001) and RUNX3 (AUC: 0.77, Sensitivity: 0.59, Specificity: 0.95, and p<0.001) had the highest performances in detection of early-stage (I+II) GC. The combined methylation of RPRM and RUNX3 in detection of early-stage GC had a higher AUC of 0.88 (SE=0.042; 95% CI:0.793-0.957; p<0.001), higher sensitivity of 0.82 and reduced specificity of 0.89. CONCLUSION: Methylation analysis of RPRM and RUNX3 in circulating cell free-DNA of plasma could be suggested as a potential biomarker for detection of GC in early-stages.

Investigation of the Correlation between Androgen Receptor and ZEB1 and its Value in Progression of Gastric Cancer.

BACKGROUND: Zinc-finger Enhancer Binding protein (ZEB1) acts as a transcription factor to promote cancer progression through regulating Epithelial to Mesenchymal Transition (EMT). It is well-known that ZEB1 mRNA expression is directly induced by both Estrogen Receptor (ER) and Progesterone Receptor (PR). Moreover, Androgen Receptor (AR) and PR could bind to the same regulatory element. Since it has been shown that AR overexpresses in Gastric Cancer (GC) as a male-predominant tumor, the goal of this study was to evaluate whether AR could regulate ZEB1 expression in GC. METHODS: The expression profile of ZEB1 in 60 fresh GC and adjacent non-tumor tissues and 50 normal gastric specimens was assessed by qRT-PCR, and the association of ZEB1 expression with clinicopathological features was investigated. Furthermore, possible correlation between ZEB1 and AR was evaluated to elucidate a novel prognostic marker using Kaplan-Meier method and Cox regression model. Finally, molecular interaction of ZEB1 and AR was assessed using a potent AR antagonist in GC cells. RESULTS: Among GC patients, 70.2% (40/57) overexpressed ZEB1 and 64.91% (37/57) overexpressed AR relative to normal gastric tissues. ZEB1 overexpression was significantly correlated with the AR overexpression in GC patients. Moreover, ZEB1 overexpression was remarkably associated with lower overall survival; however, it was not an independent prognostic factor. Evidence shows that simultaneous evaluation of ZEB1 and AR expression could independently predict survival of GC patients (HR= 2.193, p=0.047). CONCLUSION: These findings have clinical importance suggesting simultaneous evaluation of ZEB1 and AR expression as a potential prognostic marker. Moreover, AR may regulate ZEB1 expression in GC cells proposing a possible promising targeted therapy for GC patients.

An overview of microRNAs: Biology, functions, therapeutics, and analysis methods.

MicroRNAs (miRNAs) are a class of small noncoding RNAs, which function in posttranscriptional regulation of gene expression. They are powerful regulators of various cellular activities including cell growth, differentiation, development, and apoptosis. They have been linked to many diseases, and currently miRNA-mediated clinical trial has shown promising results for treatment of cancer and viral infection. This review provides an overview and update on miRNAs biogenesis, regulation of miRNAs expression, their biological functions, and role of miRNAs in epigenetics and cell-cell communication. In addition, alteration of miRNAs following exercise, their association with diseases, and therapeutic potential will be explained. Finally, miRNA bioinformatics tools and conventional methods for miRNA detection and quantification will be discussed.

Expression Analysis of PVT1, CCDC26, and CCAT1 Long Noncoding RNAs in Acute Myeloid Leukemia Patients.

BACKGROUND: Recent evidence indicates that the PVT1, CCDC26, and CCAT1 long noncoding RNAs (lncRNAs) are involved in the leukemogenic process. This study quantified the expression levels of the PVT1, CCDC26, and CCAT1 lncRNAs in patients with acute myeloid leukemia (AML) and also correlated their expression levels with the clinicopathological features of the patients. MATERIALS AND METHODS: The expression levels of the PVT1, CCDC26, and CCAT1 lncRNAs were analyzed using quantitative reverse transcription-polymerase chain reaction of bone marrow specimens obtained from 86 AML patients, 48 AML-M3 patients, and 40 normal controls. RESULTS: No differences were found between the combined AML patient populations and the healthy controls with respect to the expression levels of PVT1, CCDC26, and CCAT1 (p = 0.35, p = 0.09, and p = 0.77, respectively). However, compared with the controls, the AML-M3 patients had higher PVT1 expression (p = 0.017). Furthermore, high-risk AML-M3 patients manifested higher expression levels of PVT1 than low- and intermediate-risk groups. In addition, distinctive CCDC26 and CCAT1 expression levels were observed among patients with different French-American-British subtypes (p = 0.001 for CCDC26 and p = 0.013 for CCAT1). Compared with the healthy controls, AML-M4 and M5 had higher CCAT1 expression (p = 0.04) and AML-M2 and AML-M4/M5 patients had higher CCDC26 expression (p < 0.001 and p = 0.02, respectively). In addition, different patterns of CCDC26 expression were found among the different cytogenetic risk subtypes (p = 0.005). Finally, patients with intermediate cytogenetic risk showed higher CCDC26 expression levels. CONCLUSION: The differential expression of the PVT1, CCDC26, and CCAT1 lncRNAs in different AML subtypes suggests that the deregulation of these transcripts may function in the multistep leukemogenic process and that they may serve as new therapeutic targets for this malignancy.

Colorectal Cancer Screening: A Comprehensive Review to Recent Non-Invasive Methods.

Colorectal cancer (CRC) is one of the most common cancers worldwide and considered to be one of the hassles in medical communities. CRC develops from precancerous polyps in the colon or rectum and is preventable and curable by an early diagnosis and with the removal of premalignant polyps. In recent years, scientists have looked for inexpensive and safe ways to detect CRC in its earliest stages. Strong evidence shows that screening for CRC is a crucial way to reduce the incidence and mortality of this devastating disease. The main purpose for screening is to detect cancer or pre-cancer signs in all asymptomatic patients. In this review, we holistically introduce major pathways involved in the initiation and progression of colorectal tumorgenesis, which mainly includes chromosome instability (CIN), microsatellite instability (MSI), the CpG island methylator phenotype (CIMP), and we then will discuss different screening tests and especially the latest non-invasive fecal screening test kits for the detection of CRC.

A Comparative Cytotoxic Evaluation of Disulfiram Encapsulated PLGA Nanoparticles on MCF-7 Cells.

Background: Disulfiram is oral aldehyde dehydrogenase (ALDH) inhibitor that has been used in the treatment of alcoholism. Recent studies show that this drug has anticancer properties; however, its rapid degradation has limited its clinical application. Encapsulation of disulfiram polymeric nanoparticles (NPs) may improve its anticancer activities and protect rapid degradation of the drug. Materials andMethods: A poly (lactide-co-Glycolide) (PLGA) was developed for encapsulation of disulfiram and its delivery into breast cancer cells. Disulfiram encapsulated PLGA NPs were prepared by nanoprecipitation method and were characterized by Scanning Electron Microscopy (SEM). The loading and encapsulation efficiency of NPs were determined using UV-Visible spectroscopy. Cell cytotoxicity of free and encapsulated form of disulfiram is also determined using MTT assay. Results: Disulfiram encapsulated PLGA NPs had uniform size with 165 nm. Drug loading and entrapment efficiency were 5.35 ±0.03% and 58.85±1.01%. The results of MTT assay showed that disulfiram encapsulated PLGA NPs were more potent in induction of apoptosis compare to free disulfiram. Conclusion: Based on the results obtained in the present study it can be concluded that encapsulation of disulfiram with PLGA can protect its degradation in improve its cytotoxicity on breast cancer cells.

Osteopontin plays a unique role in resistance of CD34+/CD123+ human leukemia cell lines KG1a to parthenolide.

OBJECTIVES: To determine if parthenolide (PTL) is cytotoxic for leukemia-like KG1a cells and if it involves in certain molecular-mediated resistance, especially osteopontin (OPN). METHODS: PTL/daunorubicin (DNR)-treated KG1a cells were examined for viability using MTT and colony-formation assay, and stained for apoptosis using AV/PI. The gene and protein expression were evaluated by qReal-time PCR and Western blotting analysis, respectively. OPN gene was inhibited by OPN siRNA. The cells were stained for various fractions using PE anti-CD34, FITC anti-CD38 and PerCP anti-CD123. RESULTS: Cell viability and proliferation assay exhibited KG1a cells are relatively refractory to used concentrations of PTL. OPN mRNA and protein levels increased in response to PTL. Suppression of OPN with siRNA increased the cytotoxic effects of PTL on KG1a cells. PTL treatment and OPN siRNA suppression in KG1a cells resulted in a decrease of mRNA expression of AKT, mTOR, ß-catenin, and Phosphatase and tensin homolog (PTEN). The sub-population cells of CD34+ and CD123+ from KG1a cells are enriched by PTL treatment. CONCLUSION: Parthenolide in spite of the reduction in gene expression of AKT, mTOR or beta-catenin, stimulates the OPN expression in KG1a cells. The OPN expression pattern in KG1a cells could be compatible with CD34+/CD123+ subtype enrichment by PTL which in turn implies OPN's unique role in resistance of cell populations characterized by CD34+/CD123+ phenotype.

The Relationship between STR-PCR Chimerism Analysis and Chronic GvHD Following Hematopoietic Stem Cell Transplantation.

Background: The study attempts to assess the relationship between chimerism analysis using polymerase chain reaction of short tandem repeat (STR) and the incidence of chronic graft versus host disease (GvHD) as well as survival. Subjects and Methods: The retrospective cohort included all patients who received allo-HSCT during 2005-2013. Data collected by day +100 were reviewed in terms of the incidence of chronic GvHD and survival. Chimerism was evaluated for whole blood, T-cell and PMN cells on days 15, 30 and 60, respectively using polymerase chain reaction of short tandem repeat (STR). Results: Forty (69%) patients developed chronic GvHD, 11 (19%) relapsed and 22 (39.7%) expired during the study. There was a significant relationship between chronic GvHD and chimerism analysis including whole blood on day 60 (p=0.001), Polymorphonuclear neutrophil (PMN) on day 60 (p=0.05), T-cell on days 15 (p=0.028), 30 (p=0.01) and 60 (p=0.004). Patients with chronic GvHD showed a long-term survival as compared with those without chronic GvHD (p=0.0013). Conclusion: Conducting continuous analysis of chimerism provides an opportunity to initiate immediate measures in order to prevent complications.

Parthenolide Induces Apoptosis in Committed Progenitor AML Cell line U937 via Reduction in Osteopontin.

BACKGROUND: Interfering with cell proliferation and survival is a critical role for antineoplastic drugs leading to cell death through induction of apoptosis. Alternative treatments with herbal extracts offer insights into acute myeloid leukemia (AML) therapy. Parthenolide (PTL), an extract from feverfew, induces apoptosis in primary human leukemia stem cells (LSCs) and bulk leukemic cell populations. Osteopontin (OPN) preserves cell viability in response to anticancer agents and its receptors could be utilized for therapeutic targeting of cancer cells. METHODS: U937 cells were cultured in RPMI 1640 with concentrations of 2, 4, 6, 8, and 10 µM PTL for 20-24 hours for MTT assays. Apoptosis assays were performed with Annexin V-Alexa Fluor-488/PI as Annexin V+/PI- and Annexin V+/PI+ to measure early and late apoptosis, respectively. Quantitative real-time PCR was used to measure OPN gene expression using the 2(-ΔΔCt) method. The PTL-treated cells were stained with FITC-CD38 antibody for flow cytometry analyses. Data were compared using one-way analysis of variance (ANOVA) by SPSS 19. RESULTS: Parthenolide inhibited growth of U937 cells with IC25 and IC50 values of 4 and 5.8 µM, respectively. Death induction with PTL was apoptotic. Flow cytometry showed a significant decrease in the percentage of CD38+ U937 cells in response to PTL. Osteopontin gene expression decreased in response to PTL. CONCLUSION: PTL induced apoptosis and reduced OPN gene expression in U937 cells.

The inhibitory effect of disulfiram encapsulated PLGA NPs on tumor growth: Different administration routes.

The strong anticancer activity of disulfiram is hindered by its rapid degradation in blood system. A novel folate-receptor-targeted poly (lactide-co-glycolide) (PLGA)-polyethylene glycol (PEG) nanoparticle (NP) is developed for encapsulation and delivery of disulfiram into breast cancer tumor using passive (EPR effect) and active (folate receptor) targeting. The anticancer activity of disulfiram and its effect on caspase-3 activity and cell cycle are studied. The administration of encapsulated PLGA NPs using intra-peritoneal, intravenous and intra-tumor routes is investigated using animal model. Disulfiram shows strong cytotoxicity against MCF7 cell line. The activity of caspase-3 inhibited with disulfiram via dose dependent manner while the drug causes cell cycle arrest in G0/G1 and S phase time-dependently. The encapsulated disulfiram shows higher activity in apoptosis induction as compared to free drug. In nontoxic dose of encapsulated disulfiram, the highest and lowest efficacy of NPs in tumor growth inhibition is observed for intravenous injection and intraperitoneal injection. It is suggested that administration of disulfiram by targeted PLGA nanoparticles using intravenous injection would present an alternative therapeutic approach for solid tumor treatment.

Delivery of disulfiram into breast cancer cells using folate-receptor-targeted PLGA-PEG nanoparticles: in vitro and in vivo investigations.

BACKGROUND: A folate-receptor-targeted poly (lactide-co-Glycolide) (PLGA)-Polyethylene glycol (PEG) nanoparticle is developed for encapsulation and delivery of disulfiram into breast cancer cells. After a comprehensive characterization of nanoparticles, cell cytotoxicity, apoptosis induction, cellular uptake and intracellular level of reactive oxygen species are analyzed. In vivo acute and chronic toxicity of nanoparticles and their efficacy on inhibition of breast cancer tumor growth is studied. RESULTS: The folate-receptor-targeted nanoparticles are internalized into the cells, induce reactive oxygen species formation, induce apoptosis and inhibit cell proliferation more efficiently compared to the untargeted nanoparticles. The acute and toxicity test show the maximum dose of disulfiram equivalent of nanoparticles for intra-venous injection is 6 mg/kg while show significant decrease in the breast cancer tumor growth rate. CONCLUSION: It is believed that the developed formulation could be used as a potential vehicle for successful delivery of disulfiram, an old and inexpensive drug, into breast cancer cells and other solid tumors.

Expression pattern of hTERT telomerase subunit gene in different stages of chronic myeloid leukemia.

Telomerase is activated in chronic myeloid leukemia (CML); however, it is not known whether the catalytic telomerase reverse transcriptase subunit (hTERT) is vital in the progression of this disease. This study involved patients with CML in the chronic phase (pretreatment and after treatment), accelerated and blastic phase. Expression of the hTERT gene differed significantly among the four major groups (p < 0.05). We also compared hTERT expression according to demographic parameter such as age and sex, and found no significant differences (p > 0.05). Taken together, our findings suggest the importance of hTERT as a valuable molecular marker in the follow-up of patients with CML, which may have clinical implications for the prognosis.

Evaluation of antitumor activity of a TGF-beta receptor I inhibitor (SD-208) on human colon adenocarcinoma.

BACKGROUND: Transforming growth factor-ß (TGF-ß) pathway is involved in primary tumor progression and in promoting metastasis in a considerable proportion of human cancers such as colorectal cancer (CRC). Therefore, blockage of TGF-ß pathway signaling via an inhibitor could be a valuable tool in CRC treatment. METHODS: To evaluate the efficacy of systemic targeting of the TGF-ß pathway for therapeutic effects on CRC, we investigated the effects of a TGßRI (TGF-ß receptor 1) or TßRI kinase inhibitor, SD-208, on SW-48, colon adenocarcinoma cells. In this work, in vitro cell proliferation was studied by methyl thiazolyl tetrazolium (MTT) and bromo-2'-deoxyuridine (BrdU) assays. Also, the histopathological and immunohistochemical evaluations were conducted by hematoxylin and eosin, and Ki-67 and CD34 markers were stained, respectively. RESULTS: Our results showed no significant reduction in cell proliferation and vessel formation (170 ± 70 and 165 ± 70, P > 0.05) in treated SW-48 cells with SD-208 compared to controls. CONCLUSION: Our data suggested that SD-208 could not significantly reduce tumor growth and angiogenesis in human colorectal cancer model at least using SW-48 cells.

Autocrine human growth hormone expression leads to resistance of MCF-7 cells to tamoxifen.

Tamoxifen is the most common antiestrogen used in the treatment of estrogen-positive breast cancer but its adverse effects and also resistance to this drug are serious challenges in the treatment of breast cancer. Characterization of mechanisms responsible for these adverse effects can lead to design of more efficient therapeutic strategies for the treatment of breast cancer. Here, we used a cellular model to evaluate the effects of autocrine expression of human growth hormone on responses of cells to tamoxifen. Our results imply for the first time that autocrine expression of growth hormone in human breast adenocarcinoma cell line, MCF-7, results in increase in cell proliferative capacity of cells even in the presence of tamoxifen. This effect may be due to up-regulation of G-coupled estrogen receptor, GPR30, which is activated by tamoxifen.