CircZNF609 and circNFIX as possible regulators of glioblastoma pathogenesis via miR-145-5p/EGFR axis.

Glioblastoma is a rare and deadly malignancy with a low survival rate. Emerging evidence has shown that aberrantly expressed circular RNAs (circRNAs) play a critical role in the initiation and progression of GBM tumorigenesis. The oncogenic function of circZNF609 and circNFIX is involved in several types of cancer, but the role and underlying mechanism of these circRNAs in glioblastoma remain unclear. In this study, we hypothesized that circZNF609 and circNFIX may regulate EGFR through sponging miR-145-5p. Herein, we assessed the expression levels of circZNF609, circNFIX, miR-145-5p, and EGFR using quantitative polymerase chain reaction in glioblastoma patients and normal brain samples. The results showed that circZNF609, circNFIX, and EGFR expression levels were upregulated and miR145-5p was downregulated (p = 0.001, 0.06, 0.002, and 0.0065, respectively), while there was no significant association between clinicopathological features of the patients and the level of these genes expression. We also found a significant inverse correlation between miR145-5p and the expression of cZNF609, cNFIX and EGFR (p = 0.0003, 0.0006, and 0.009, respectively). These findings may open a new window for researchers to better understand the potential pathways involved in GBM pathogenesis. In conclusion, it may provide a new potential pathway for the development of effective drugs for the treatment of GBM patients.

Comparison of Plasma Levels of MicroRNA-155-5p, MicroRNA-210-3p, and MicroRNA-16-5p in Rheumatoid Arthritis Patients with Healthy Controls in a Case-control Study.

Rheumatoid arthritis is a chronic autoimmune disease that causes inflammation and destruction of the joints. The objective of the current study was to evaluate the expression of microRNA (miR)-155-5p, miR-210-3p, and miR-16-5p in the plasma of patients with rheumatoid arthritis in comparison with a healthy control group to attain an expression profile for earlier diagnosis and treatment. To carry out this study, 100 individuals were chosen as two equally sized groups of rheumatoid arthritis patients and healthy controls. Five milliliters of blood were drawn from each individual, and plasma RNA was extracted using Trisol solution. Complementary DNAs were synthesized using the Moloney leukemia virus (MMLV) and deoxynucleoside triphosphate (dNTP). Finally, real-time polymerase chain reaction (PCR) was implemented using the SYBR Green kit. The mean expression of miR-155-5p, miR-210-3p, and miR-16-5p were 2.46±2.79, 1.97±1.90, and 69.62±88.44 in the rheumatoid arthritis group, and 0.34±0.33, 9.82±9.34, and 7.94±7.09 in the healthy group, respectively. Additionally, significant differences were revealed in the relative  expression of the selected microRNAs in 4 subgroups of rheumatoid arthritis patients with different disease activities based on the disease activity score 28 (DAS28). ROC curve analysis showed that miR-155-5p (area under the curve, AUC=0.90, sensitivity=80%, specificity=81%), miR-210-3p (AUC=0.75, sensitivity=66%, specificity=71%), and miR-16-5p (AUC=0.96, sensitivity=89%, specificity=82%) could be potential biomarkers for rheumatoid arthritis diagnosis. Increased expressions of miR-16-5p and miR-155-5p and decreased expression of miR-210-3p in rheumatoid arthritis patients compared with healthy individuals demonstrate the effectiveness of these microRNAs in disease incidence and progression. Thus, the expression levels of these microRNAs can be used for diagnostic and therapeutic purposes.

RET Proto-Oncogene Mutational Analysis in 45 Iranian Patients Affected with Medullary Thyroid Carcinoma: Report of a New Variant.

BACKGROUND: The aim of this study was to identify germline mutation of the RET (rearranged during transfection) gene in patients with medullary thyroid carcinoma (MTC) and their first-degree relatives to find presymptomatic carriers for possible prophylactic thyroidectomy. Methods/Patients. We examined all six hot spot exons (exons 10, 11, 13, and 14-16) of the RET gene by PCR and bidirectional Sanger sequencing in 45 Iranian patients with MTC (either sporadic or familial form) from 7 unrelated kindred and 38 apparently sporadic cases. First-degree relatives of RET positive cases were also genotyped for index mutation. Moreover, presymptomatic carriers were referred to the endocrinologist for further clinical management and prophylactic thyroidectomy if needed. RESULTS: Overall, the genetic status of all of the participants was determined by RET mutation screening, including 61 affected individuals, 22 presymptomatic carriers, and 29 genetically healthy subjects. In 37.5% (17 of 45) of the MTC referral index patients, 8 distinct RET germline mutations were found, including p.C634R (35.3%), p.M918T (17.6%), p.C634Y (11.8%), p.C634F (5.9%), p.C611Y (5.9%), p.C618R (5.9%), p.C630R (5.9%), p.L790F (5.9%), and one uncertain variant p.V648I (5.9%). Also, we found a novel variant p.H648R in one of our apparently sporadic patients. CONCLUSION: RET mutation detection is a promising/golden screening test and provides an accurate presymptomatic diagnostic test for at-risk carriers (the siblings and offspring of the patients) to consider prophylactic thyroidectomy. Thus, according to the ATA recommendations, the screening of the RET proto-oncogene is indicated for patients with MTC.

Plasma Levels of MicroRNA-146a-5p, MicroRNA-24-3p, and MicroRNA-125a-5p as Potential Diagnostic Biomarkers for Rheumatoid Arthris.

Rheumatoid arthritis (RA) is an autoimmune disease that is characterized by inflammation of the articular tissue. This study aims to evaluate the expression of microRNA (miR)-146a-5p, miR-24-3p, and miR-125a-5p in the plasma of RA patients and compare them with those of healthy controls to obtain a specific expression profile for earlier diagnosis and assistance in treating patients. This study was performed on 50 RA patients and 50 healthy controls. Five microliters of blood were taken from each patient/control. Plasma RNA was extracted using the Trisol solution. cDNAs were synthesized; using moloney murine leukemia virus (MMLV) and deoxynucleoside triphosphate (dNTP). Real-time PCR was performed using SYBR green kit. The mean expression of miR-146a-5p, miR-24-3p, and miR-125a-5p in the RA group were 8.1±1.9, 6.5±1.2, and 6.8±2.2 and in the healthy group were 4.8±1.6, 3.6±2.2, and 3.4±1.7, respectively. Significant differences were also observed in the mean expression of these three miRNAs in four subgroups of RA patients with different disease activity based on disease activity score 28 (DAS28) (p<0.05). ROC curve analysis showed that miR-146a-5p (AUC=0.8, sensitivity= 96%, specificity=86%), miR-24-3p (AUC=0.7, Sensitivity=95%, Specificity=75%) and miR-125a-5p (AUC=0.71, sensitivity=93%, specificity=84%) could be used as suitable biomarkers for RA diagnosis. Increased expressions of miR-146a-5p, miR-24-3p, and miR-125a-5p in RA patients indicate that the miRNAs are involved in disease incidence and progression, and the measurement of their expression can play an essential role in the diagnosis and treatment of the disease.

Arsenic trioxide and BIBR1532 synergistically inhibit breast cancer cell proliferation through attenuation of NF-κB signaling pathway.

AIMS: Despite the remarkable anti-proliferative effects of Arsenic trioxide (ATO) in breast cancer cells, the requirement of high, toxic concentrations to induce apoptosis may cause serious side effects in patients. In the present study, we aimed to use BIBR1532, an hTERT inhibitor, in combination with ATO to sensitize MCF7 and MDA-231 cells to lower concentrations of ATO. MAIN METHODS: Breast cancer cell lines MCF7 and MDA-231 were cultured and treated with different doses of ATO and BIBR1532 for 48 h and its effects on cell survival and proliferation were analyzed by MTT, crystal violet staining, colony formation assay, cell cycle, AnnexinV/PI and Real-time PCR tests. KEY FINDINGS: ATO and BIBR1532 synergistically inhibited proliferation and colony-forming ability of breast cancer cells. Besides, BIBR1532 augmented ATO-induced cytotoxic effects via triggering G1 cell cycle arrest and induction of apoptosis coupled with the down-regulation of NF-κB target genes that were involved in cell cycle progression (e.g. CCND1 and CDK6) and prevention of apoptosis such as Bcl-2, Bcl-xl, c-IAP2, and Survivin Respectively. Moreover, ATO-BIBR1532 significantly reduced the mRNA expression level of RELA, NFKB1, and several validated target genes of the NF-κB signaling pathway including NFKBIA, VEGFC, c-Myc, and hTERT. SIGNIFICANCE: The combination of ATO and BIBR1532 synergistically induced its anti-proliferative effect in breast cancer cells by targeting the two key cancer-related pathways, hTERT and NF-κB, and disrupting their feed-forward loop at the same time which result in the reduction of NF-κB transcriptional activity and subsequent down-regulation of its target genes.

Investigation of promoter methylation of FSCN1 gene and FSCN1 protein expression in differentiated thyroid carcinomas.

FSCN1 gene encodes an actin-bundling protein, FSCN1, which is involved in formation of actin-based structures that contribute to cell migration. High levels of FSCN1 expression is observed in cells with extended membranes and protrusions. Moreover, up-regulation of FSCN1 has been reported in several epithelial carcinomas. Therefore, FSCN1 is thought to play a role in cell movement and invasion. However, the mechanism behind FSCN1 up-regulation is not known. We investigated the expression of FSCN1 using immunohistochemistry. Methylation-specific PCR was adopted to analyze the methylation status of FSCN1 promoter as a potential regulatory mechanism in FSCN1 expression. The samples included papillary thyroid carcinoma, follicular thyroid carcinoma and goiter samples (controls). Methylation of FSCN1 promoter was observed in 50% of follicular, 48.6% of papillary and 60% of controls. The promoter was unmethylated in 16.7% of follicular samples, 5.7% of papillary samples and 26.7% of controls. In the remaining 33.3% of follicular and 45.7% of papillary samples as well as 13.3% of controls, both methylated and unmethylated alleles were amplified, a condition referred to as semi-methylation. The results showed that FSCN1 promoter was significantly hypomethylated in papillary cases while the methylation status was not significantly altered in follicular cases. On the other hand, FSCN1 was expressed in only nine papillary samples. Regarding protein expression and methylation status, we suggest that hypomethylation of FSCN1 promoter in papillary thyroid carcinoma does not lead to overexpression of FSCN1 and that there might be other regulatory mechanisms involved in FSCN1 up-regulation.

TLR4 blockade using TAK-242 suppresses ovarian and breast cancer cells invasion through the inhibition of extracellular matrix degradation and epithelial-mesenchymal transition.

Numerous links exist between inflammation and tumor development. Toll-like receptor 4 (TLR4) expression by tumor cells can be a contributing factor that promotes tumor cell proliferation, survival, migration, and metastasis. In this study, we explored the impact of TLR4 inhibition using TAK-242, a specific inhibitor of TLR4, on the invasion properties of ovarian (A2780CP, 2008C13, SKOV3, and A2780S) and breast (MCF7, SKBR3, MDA-MB-231, and BT-474) cancer cell lines. Six out of eight cell lines expressed TLR4 and its downstream mediators (MyD88, NF-ĸB1, and RELB), indicating that these cell lines could be proper candidates for the TLR4 inhibition. TAK-242 induced a cytotoxic effect on all tested cell lines; however, a different cell sensitivity pattern was noticeable. Interestingly, in the TLR4-expressing cell lines, there was a significant correlation between the TLR4/MyD88 expressions and the cancer cell response to TAK-242: the higher the expression, the higher the IC50. To the best of our knowledge, no study has addressed the effects of TAK-242 on invasive abilities of cancer cells and our study suggests for the first time that TAK-242 could considerably decrease invasion properties of ovarian and breast cancer cell lines. We found that not only did TAK-242 reduce the enzymatic activity of MMP2 and MMP9, but also down-regulated gene expressions of epithelial-mesenchymal transition (EMT)-related genes. In sum, it seems that targeting TLR4 using TAK-242 possesses novel promising potential in cancer treatment strategies and may prevent invasion in patients suffering from ovarian and breast cancers, especially in those with over-expression of TLR4.

Evaluation of the Prevalence of Exons 1 And 10 Polymorphisms of LHCGR Gene and Its Relationship with IVF Success.

BACKGROUND: Luteinizing hormone receptor gene shows four nonsynonymous polymorphisms within the exons. Three of these polymorphisms, i.e. rs4539842 (an insertion of 6bp CTGCAG at nucleotide position 54), rs12470652 (c.827A>G/p.Asn 291Ser), and rs2293275(c.935G>A/p.Ser312Asn) have been studied more frequently. Beside other hormones, LH and FSH have an important role in production of competent oocyte and female fertility. Therefore, the objective of the current study was to investigate the prevalence of exons 1(rs4539842) and 10(rs12470652, rs2293275) polymorphisms of the LHCGR gene and its relationship with successful IVF in Iranian infertile women. METHODS: SNPs in exons 1 and 10 were analyzed in 100 women of two equally sized groups of IVF failure and IVF success women using genomic DNA. For polymorphisms in exon 10, PCR and direct sequencing were used and for the polymorphism in exon 1, RFLP technique was used. The RFLP technique is confirmed by sequencing. RESULTS: Our results showed significant difference in allelic frequency of SNP rs2293275 among IVF successful and IVF failure groups (p=0.001). For this variation, AA genotype (A allele) was shown to have protective effect against IVF failure (p=0.03 and OR=0.04), while GG genotype (G allele) was a susceptive genotype to IVF failure (p=0.003 and OR=3.88).Allelic frequency of SNP rs4539842 also showed significant difference between the two groups (p=0.0025). For this SNP, subjects with no 6bp insertion (homozygote deletion genotype) were susceptible to failure in IVF (p=0.009 and OR=2.93). CONCLUSION: It has been revealed that two common SNPs (rs4539842 and rs2293275) in the LHCGR gene are associated with the outcome of IVF in Iranian infertile women. Thus, these two SNPs can be suggested to be used as predictors for IVF outcome in Iranian population.

Arsenic trioxide induces cell cycle arrest and alters DNA methylation patterns of cell cycle regulatory genes in colorectal cancer cells.

AIMS: Cell cycle dysregulation is important in tumorigenesis. Transcriptional silencing of cell cycle regulatory genes, due to DNA methylation, is a common epigenetic event in malignancies. As2O3 has been shown to induce cell cycle arrest and also to be a potential hypomethylating agent. Our study aimed to investigate DNA methylation patterns of cell cycle regulatory genes promoters, the effects of Arsenic trioxide (As2O3) on the methylated genes and cell cycle distribution in colorectal cancer (CRC) cell lines. MAIN METHODS: The methylation-specific PCR (MSP) and/or restriction enzyme-based methods were used to study the promoter methylation patterns of 24 cell cycle regulatory genes in CRC cell lines. Gene expression level and cell cycle distribution were determined by Real-time PCR and flow cytometric analyses, respectively. KEY FINDINGS: Our methylation analysis indicated that only promoters of RBL1 (p107), CHFR and p16 genes were aberrantly methylated in three cell lines. As2O3 significantly decreased DNA methylation in promoter regions of these genes and restored their expression. We found that As2O3 significantly reduced the expression of DNA methyltransferase 1 (DNMT1) and increased arsenic methyltransferase (AS3MT). Furthermore, As2O3 altered transcriptional activity of several unmethylated cell cycle regulatory genes including cyclin B1, E1, D1, GADD45A and p21. Cell cycle flow cytometry analysis showed As2O3 induced G2/M arrest in all three cell lines. SIGNIFICANCE: These data suggest that demethylation and alteration in the expression level of the cell cycle-related genes may be possible mechanisms in As2O3-induced cell cycle arrest in colorectal cancer cells.

Targeting PML/RARalpha transcript with DNAzymes results in reduction of proliferation and induction of apoptosis in APL cells.

DNAzymes are nucleic acid enzymes that can recognise specific RNA substrate via Watson-Crick base pairing and cleave it with multiple turnovers. We have designed and examined the effects of DNAzymes targeting the PML/RARalpha fusion gene in acute promyelocytic leukaemia (APL). The DNAzymes (DZ1 and DZ3) were designed to cleave the PML/RARalpha transcript at the GC nucleotides at the fusion point and three nucleotides upstream of that respectively. Disabled DNAzymes were synthesised and used as controls. Cell-free cleavage reactions were performed on total RNA from NB4 cell line and PML/RARalpha and RARalpha-amplified RNA fragments (aRNA). Postcleavage examination showed that DZ1 and DZ3 cleave PML/RARalpha efficiently and specifically. NB4 APL cells transfected with DZ1 or DZ3 showed a significant suppression of PML/RARalpha protein expression. These DNAzymes also inhibited the proliferation of NB4 cells, reduced the viability rate, and induced apoptosis in these cells. The disabled DNAzymes showed no effect on NB4 cells. The two DNAzymes did not produce any significant effect on K562 cells, which were used as control cells. DNAzymes are more resistant to serum than ribozymes. These data show that targeting the PML/RARalpha fusion gene with DNAzymes can induce apoptosis in APL cells and may have a role in the treatment of APL. They also show DNAzymes are promising tools for targeting specific genes in leukaemia.