Mesenchymal stem cell-derived exosomes enriched with miR-218 reduce the epithelial-mesenchymal transition and angiogenesis in triple-negative breast cancer cells.

BACKGROUND: The epithelial-mesenchymal transition (EMT) and angiogenesis are morphogenetic processes implicated in tumor invasion and metastasis. It is found that the aberrant expression of microRNAs (miRNAs) contributes to these processes. Exosomes are considered potential natural vehicles for miRNA delivery in cancer therapy. miR-218 is one of the tumor suppressor miRNAs and its downregulation is associated with EMT and angiogenesis. We aimed to use adipose mesenchymal stem cells-derived exosomes (ADMSC-exosomes) for miR-218 delivery to breast cancer cells and evaluate miR-218 tumor-suppressing properties in vitro. METHODS: Exosomes were isolated from conditioned media of ADMSCs. miR-218 was loaded to exosomes using electroporation. mRNA expression of target genes (Runx2 and Rictor) in MDA-MB-231 breast cancer cells was evaluated by qPCR. To explore the effects of miR-218 containing exosomes on breast cancer cells, viability, apoptosis, and Boyden chamber assays were performed. The angiogenic capacity of MDA-MB-231 cells after treatment with miR-218 containing exosomes was assessed by in vitro tube formation assay. RESULTS: miR-218 mimic was efficiently loaded to ADMSC-exosomes and delivered to MDA-MB-231 cells. Exposure to miR-218 containing exosomes significantly decreased miR-218 target genes (Runx2 and Rictor) in MDA-MB-231 cells. They increased the expression of epithelial marker (CDH1) and reduced mesenchymal marker (CDH2). miR-218 restoration using miR-218 containing exosomes reduced viability, motility, invasion, and angiogenic capacity of breast cancer cells. CONCLUSIONS: These findings suggest that ADMSC-exosomes can efficiently restore miR-218 levels in breast cancer cells and miR-218 can prevent breast cancer progression with simultaneous targeting of angiogenesis and EMT.

miRNAs Delivery for Cancer-associated Fibroblasts' Activation and Drug Resistance in Cancer Microenvironment.

Cancer-associated fibroblasts (CAFs) as a major component of cancer stroma contribute to diverse procedures of most solid tumors and might be a targeted cancer therapy approach. Their specified features, related signaling pathways, distinct biomarkers, and sub-populations need to be deciphered. There is a need for CAF extraction or induction for in vitro investigations. Some miRNAs could activate CAF-like phenotype and they also interfere in CAF-mediated drug resistance, aggressiveness, and metastatic behaviors of several cancer cell types. Due to the complex relevance of miRNA and CAFs, these non-coding oligonucleotides may serve as attractive scope for anti-cancer targeted therapies, but the lack of an efficient delivery system is still a major hurdle. Here, we have summarized the investigated information on CAF features, isolation, and induction procedures, and highlighted the miRNA-CAF communications, providing special insight into nano-delivery systems.

Determining buffer conditions for downstream processing of VLP-based recombinant hepatitis B surface antigen using multimodal resins in bind-elute and flow-through purification modes.

The difficulties in purification of VLP-based recombinant hepatitis B surface antigen (rHBsAg) are mainly emerged from inefficient semi-purification step plus proteins physicochemical properties and these issues make the downstream processing (DSP) very lengthy and expensive. In this study, optimization of rHBsAg (recombinantly-expressed in Pichia pastoris) DSP was performed using selection of buffering conditions in the semi-purification step. In the semi-purification optimization step, up to 73% of the protein impurities were eliminated and the utmost increase in rHBsAg purity (ca. 3.6-fold) was achieved using 20 mM sodium acetate, pH 4.5. By using rHBsAg binding and nonbinding situations obtained from the response surface plot in design of experiments (DOE), additional bind-elute and flow-through purification mode experiments were conducted and rHBsAg with high purity (near 100%) and recovery (> 83%) was achieved. Following assessment of critical quality attributes (i.e., purity, particle size distribution, host cell DNA, host cell protein, secondary structures, specific activity and relative potency), it was indicated that the characteristics of rHBsAg purified by the new DSP were similar or superior to the ones obtained from conventional DSP. The purification performance of the resin was constantly retained (97-100%) and no significant resin damage took place after 10 adsorption-elution-cleaning cycles. The new DSP developed for production of rHBsAg in this study can substitute the conventional one with granting satisfactory target protein quality, long-lasting resin efficacy, shorter and less expensive process. This process may be also employable for purification of both non-VLP- and VLP- based target proteins expressed in the yeast.

Mir-4699 promotes the osteogenic differentiation of mesenchymal stem cells.

INTRODUCTION: Mesenchymal stem cells (MSCs) are drawing considerable attention in the field of regenerative medicine due to their differentiation capabilities. The miRNAs are among the most important epigenetic regulators of MSC differentiation. Our previous study identified miR-4699 as a direct suppressor of the DKK1 and TNSF11 gene expression. However, the precise osteogenic-related phenotype or mechanism caused by miR-4699 change has yet to be dealt with in depth. MATERIAL AND METHODS: In the present study, miR-4699 mimics were transfected into human Adipose tissue-derived mesenchymal stem cells (hAd-MSCs) and osteoblast marker gene expression (RUNX2, ALP, and OCN), was analyzed to investigate whether miR-4699 promotes osteoblast differentiation of hAd-MSCs through targeting the DKK-1 and TNFSF11. We further examined and compared the effects of recombinant human BMP2 with miR-4699 on cell differentiation. In addition to quantitative PCR, analysis of alkaline phosphatase activity, calcium content assay, and Alizarin red staining were used to explore osteogenic differentiation. To evaluate the effect of miR-4699 on its target gene (on protein level) we utilized the western blotting technique. RESULTS: The overexpression of miR-4699 in hAd-MSCs resulted in the stimulation of alkaline phosphatase activity, osteoblast mineralization, and the expression of RUNX2, ALP, and OCN osteoblast marker genes. CONCLUSION: Our findings indicated that miR-4699 supported and synergized the BMP2-induced osteoblast differentiation of mesenchymal stem cells. We suggest, thereof, the utilization of hsa-miR-4699 for further in vivo experimental investigation to reveal the potential therapeutic impact of regenerative medicine for different types of bone defects.

Effect of Calcitriol Treated Mesenchymal Stem Cells as an Immunomodulation Micro-environment on Allergic Asthma in a Mouse Model.

BACKGROUND: Allergic asthma is a chronic inflammatory illness of the respiratory system characterized by an increase in the number of inflammatory cells in the airways and trouble breathing. Mesenchymal stem cells (MSCs) have the potential to be used in inflammatory diseases as a cellular immunosuppressive treatment. They express calcitriol receptors and communicate with other immunocytes, which increases their anti-inflammatory activity. This study aimed to determine the effects of calcitriol-treated MSC treatment on allergic asthma pathways in a mouse model. METHODS: To generate a mouse model of asthma, the mice were sensitized intraperitoneally with ovalbumin (OVA) and aluminum hydroxide emulsion and then challenged intra-nasally with OVA. On day 14, experimental mice received tail vein injections of calcitriol-treated MSCs in PBS prior to allergen exposure. The cytokines assays including IL-4, 10, 12, 17, TGF-ß and IFN-γ, splenocytes proliferation, and histological examination of lungs samples were performed. The mice were sensitized with OVA and the response to dexamethasone treatment was compared. RESULTS: Calcitriol-treated MSCs significantly increased the levels of IL-12, TGF-ß, and IFN-γ compared to non-treated MSCs groups. Moreover, calcitriol-treated and non-treated MSCs significantly decreased IL-4 and IL-17 compared to asthmatic groups. The results of the histopathological examination showed that calcitriol-treated MSCs reduced the accumulation of inflammatory cells and bronchial wall thickening in comparison with the asthma group. CONCLUSION: Using the allergic asthma model, we were able to show that calcitriol-treated MSCs had an inhibitory impact on airway inflammation. Our findings suggest that the injection of calcitrioltreated MSCs may be a viable treatment option for allergic asthma.

Evaluation of real-time NASBA assay for the detection of SARS-CoV-2 compared with real-time PCR.

PURPOSE: In January 2020, the COVID-19 pandemic started and has severely affected all countries around the world. The clinical symptoms alone are not sufficient for a proper diagnosis. Thus, molecular tests are required. Various institutes and researchers developed real-time PCR-based methods for the detection of the virus. However, the method needs expensive equipment. In the present study, we developed a real-time NASBA assay for the detection of SARS-CoV-2. METHODS: Primers and molecular beacon probes for RdRp and N genes were designed. In silico analysis showed that primers and the probes were specific for SARS-CoV-2. The standard samples with known copy numbers of the virus were tested using the NASBA assay and an FDA-approved real-time PCR kit. A series of standard samples were prepared and tested. Clinical sensitivity, precision analysis, and clinical assessment of the assay were performed. RESULTS: The limit of detection of the assay was 200 copies/mL. The clinical sensitivity of the assay was 97.64%. The intra-assay and inter-assay for both N and RdRp genes were less than 5% and 10%, respectively. Clinical assessment of the assay showed that the positive agreement rate and negative agreement rate of the assays were determined to be 97.64% and 100%, respectively. CONCLUSIONS: The results of the present study show that the developed real-time NASBA is a sensitive and specific method for the detection of SARS-CoV-2 and is comparable with real-time PCR. NASBA is an isothermal signal amplification method, and if stand-alone fluorescent readers are available, the real-time NASBA can be used without the need for expensive thermocyclers. In addition compared to other isothermal methods like LAMP, the primer design is straightforward. Thus, real-time NASBA could be a suitable method for inexpensive SARS-CoV-2 detection.

New design and optimization of an in-house quantitative TaqMan Real-Time PCR-based assay for the detection and monitoring of occult hepatitis B virus (genotype A-J) infection.

PURPOSE: HBV DNA quantification is used for individuals with uninterpretable serological tests, occult HBV infections, decreasing the window period of the disease, and treatment follow-up. Although there are commercial qPCR assays, they are expensive. In this study, we developed a highly sensitive quantitative TaqMan Real-Time PCR with an exogenous internal control to quantify HBV DNA in serum/plasma. METHODS: A specific primer/probe set was designed for the S conserved region of various HBV genotypes. The primer/probe set was evaluated experimentally and in-silico. An exogenous internal control was included to monitor the effects of inhibitors. The standard plasmid was titrated using three different methods to prepare the seven standards for the assay. The functional characteristics of the in-house assay were evaluated using the standards. Two hundred clinical specimens were also tested. RESULTS: The LOD of the in-house assay was 40 IU/mL, and the assay was linear from 3.26Log10 to 9.26Log10 IU/mL. The analytical and clinical sensitivity of the assay was 100% and 92.15%, respectively. The analytical and clinical specificity of the assay was 100% and 98.97%, respectively. The positive and negative predictive values of the assay were determined to be 98.94% and 92.38%, respectively. The highest coefficient of variation of the inter/intra-assay was 5.1%. The accuracy was close to 100% for all standards, and the correlation between the in-house assay and commercial kit AltoStar® PCR Kits 1.5 was remarkable. The results of the clinical samples using the standards titrated using AcroMetrix™ HBV Panel, Artus® HBV RG PCR Kit, and AltoStar® PCR Kits 1.5 were comparable (r â€‹= â€‹0.942, 0.951, 0.951). CONCLUSIONS: The results indicate that the in-house assay is highly sensitive and specific, reproducible, and cost-benefit. Thus, it can be used to detect and quantify HBV DNA in research and clinical settings.

Overexpression of pigment epithelium-derived factor in breast cancer cell-derived exosomes induces M1 polarization in macrophages.

M2 macrophages, the major component of tumor microenvironment, are recognized as important player in tumor progression. M2 macrophages mediate this effect by promoting tumor angiogenesis, tumor metastasis, and suppression of tumor immunity. Reprogramming of M2 macrophages can serve as a promising strategy in cancer immunotherapy. In this study, we constructed pigment epithelium-derived factor (PEDF) expressing vector and transfected MDA-MB-231 cells with this construct. Then, exosomes were isolated from transfected cells and M2 macrophages were incubated with isolated exosomes from transfected cell. The effect of isolated exosomes on macrophage polarization was examined by real-time PCR and ELISA. The results demonstrated reprogramming of M2 macrophages after incubation with isolated exosomes from PEDF transfected cells. M2-to-M1 repolarization of macrophages was confirmed by upregulation of CD80, IRF5, MCP1, and IL-1ß and repression of CD206, Arg, TGM2, and TGF-ß. Therefore, these findings revealed that introducing PEDF into exosomes by genetic manipulation of parent cells may be a potential approach for reprogramming of M2 macrophages in cancer.

Pap Smear miR-92a-5p and miR-155-5p as potential diagnostic biomarkers of squamous intraepithelial cervical cancer.

BACKGROUND: one of the female-specific diseases with a high incidence and mortality is cervical cancer. The main cause of cervical cancer is infection with Human papilloma virus (HPV). Low-grade squamous intraepithelial lesions (LSIL) and High-grade squamous intraepithelial lesions (HSIL) usually is caused by an HPV infection. Considering the role of microRNAs (miRNAs) as diagnostic biomarkers for a variety of cancers, the aim of this study was to determine miR-92a-5p and miR-155-5p expression levels in LSIL and HSIL Pap Smear samples. METHODS: After initial bioinformatic studies, A total of 75 samples (25 samples of patients with LSIL, 25 patients with HSIL and 25 healthy individuals) were subjected to RNA extraction and cDNA synthesis. The expressions levels of confirmed miRNAs in samples of patients with LSIL, HSIL and healthy individuals were evaluated by Real time PCR analysis. To demonstration the role of predicted miRNAs as novel biomarkers in diagnosis of LSIL and HSIL, ROC curve analysis was done. RESULTS: Bioinformatics results showed that miR-92a-5p and miR-155-5p target the HPV E6 and E7 genes. The expression levels of these miRNAs were strikingly higher in Pap smear of patients with LSIL than in the healthy individuals (35.36, P = 0.001) (62.23, P = 0.001). Similarity, expression levels of miR-92a-5p and miR-155-5p were amazingly higher in patients with HSIL than in the healthy individuals (33.62, P= 0.001) (69.07, P= 0.001). Although, the levels of miR-92a-5p (0.95, P = 0. 85) and miR-155-5p (1.11, P = 0.84) exhibited no statistical differences between patients with LSIL and HSIL. Also, ROC curve analyses verified that miR-92a-5p and miR-155-5p are specific and sensitive and may serve as new biomarkers for the early detection of cervical cancer. CONCLUSION: These data suggest miR-92a-5p and miR-155-5p, which are upregulated in LSIL and HSIL, can be consider as predictive biomarkers for the prognosis of cervical cancer patients.
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Assessment of AXL and mTOR genes expression in medullary thyroid carcinoma (MTC) cell line in relation with over expression of miR-144 and miR-34a.

OBJECTIVES: The aim of the present study was to investigate the expression of AXL and mTOR genes and their targeting microRNAs (miRNAs) including miR-34a and miR-144 in Medullary Thyroid Carcinoma (MTC) cell line, TT, and determine the effect of these two miRNAs on their target genes to introduce new molecular markers or therapeutics. METHODS: The expression of miR-34a, miR-144, and their targets genes including AXL and mTOR was evaluated by quantitative Real-time PCR. Luciferase assay was performed to confirm the interaction between miRNAs and their target mRNAs. The expression level of AXL and mTOR was evaluated before and after miRNAs induction in TT cell line compared with Cos7 as control cells. RESULTS: The expression of AXL and mTOR were up-regulated significantly, while miR-34a and miR-144 were down-regulated in TT cell line compared to Cos7. After transduction, the overexpression of miR-34a and 144 caused down-regulation of both genes. Luciferase assay results showed that the mTOR is targeted by miR-34a and miR-144 and the intensity of luciferase decreased in the presence of miRNAs. CONCLUSIONS: Based on the results of the present study and since AXL and mTOR genes play a critical role in variety of human cancers, suppression of these genes by their targeting miRNAs, especially miR-34a and miR-144, can be propose as a new strategy for MTC management. However, more studies are needed to approve the hypothesis.

Design and development of a simple method for the detection and quantification of residual host cell DNA in recombinant rotavirus vaccine.

Rotavirus recombinant vaccine is usually produced in Vero cells. Residual host DNA may reside in the final product and is considered a source of contamination. WHO protocols indicate that biological products should be free of any type of impurity such as nucleic acids, endotoxins, and host cell intermediate materials. Therefore, all recombinant biological therapeutics should be assessed for residual host DNA. In the present study, a sensitive and specific real-time PCR method was developed to detect residual host cell DNA in the final product. The Beta-actin gene of Vero cells was selected to detect residual host cell DNA. One set of primers and a TaqMan probe were designed for the gene using AlleleID 6 software. Real-time PCR reactions were set up, and efficiency of 84% was obtained. The sensitivity and limit of detection of the assay were determined to be 0.176 Fg/µl and 0.044 Fg/µl, respectively. The intra-assay and inter-assay variations were 4.4% and 1.04%, respectively. Furthermore, the specificity and sensitivity of the assay were high enough, and the detection limit was lower than that of the FDA and WHO standards. This indicates that our assay is highly specific and sensitive to detect residual host DNA of Vero cells in the recombinant rotavirus vaccine.

Potential role of miR-214 in ß-catenin gene expression within hepatocellular carcinoma.

MicroRNAs (miRNAs) are important gene regulators whose dysregulations can be involved in tumorigenesis. ß-catenin, the main agent in the Wnt/ß-catenin pathway, controls various genes and its over-expression has been discovered in different kinds of cancers including Hepatocellular Carcinoma (HCC). Extensive research demonstrated that the Wnt signaling is one of the major affected pathways in HCC. This study aimed to find miRNA targeting ß-catenin gene by bioinformatic approaches and confirm this correlation to propose new therapeutic targets for HCC. Prediction of miRNAs targeting 3'-Untranslated Regions (UTR) of ß-catenin mRNA, were done using different types of credible bioinformatic databases. The luciferase assay was also recruited for further confirmation of the bioinformatic predictions. In the first step, the expression of ß-catenin was assessed in the HepG2 cell line by real-time PCR technique. Next, transduction of HepG2 cells were done by lentiviral vectors containing the desired miRNA. Then, the expression level of miRNA and the ß-catenin gene were evaluated. Based on the results obtained from different bioinformatic databases, miR-214 was selected as the potential miRNA with the highest probability in targeting ß-catenin. Furthermore, Luciferase assay results confirmed the accuracy of our bioinformatic prediction. In line with our hypothesis, after the overexpression of miR-214 in HepG2 cells, ß-catenin gene expression was reduced significantly. Gathered results indicate the miRNAs role in the down-regulation of their target genes. Hence, the results propose that miR-214 can prevent HCC development by suppressing ß-catenin and may supply a newfound approach towards HCC therapy in humans.

A Real-Time RT-PCR Assay for Genotyping of Rotavirus

Background: Human rotavirus (HRV) is the causative agent of severe gastroenteritis in children and responsible for two million hospitalizations and more than a half-million deaths annually. Sequence characteristics of the gene segments encoding the VP7 and VP4 proteins are used for the genotype classification of rotavirus. A wide variety of molecular methods are available, mainly based on reverse transcription PCR for rapid, specific and sensitive genotyping of rotaviruses. This study describes an alternative real-time PCR assay for genotyping of rotavirus. Methods: The samples of stools studied in this research have been collected from patients referred to Children's Medical Centers, Tehran, Iran. Rotavirus detection and genotyping were performed using the RT-PCR and semi-nested RT-PCR, respectively. Samples were then genotyped with a new real-time PCR. Results: The real-time PCR was able to genotype all positive samples with a mean Ct of 28.2. Besides, a concordance rate of 100% was detected between real-time PCR and semi-nested RT-PCR. Conclusion: In this study, the genotyping of rotavirus with real-time PCR showed that this method can provide several favorable features, including high sensitivity and specificity, and a wide dynamic range for rotavirus genotyping.

Investigating the inhibitory effect of miR-34a, miR-449a, miR-1827, and miR-106b on target genes including NOTCH1, c-Myc, and CCND1 in human T cell acute lymphoblastic leukemia clinical samples and cell line.

OBJECTIVES: microRNAs are small non-coding molecules that regulate gene expression in various biological processes. T-cell acute lymphoblastic leukemia (T-ALL) is a malignancy accompanied with genetic aberrations and accounts for 20% of children's and adult's ALL. Notch signaling pathway dysregulation occurs in 60% of T-ALL cases. In the present study, we aimed to determine the relationship between miRNAs and genes involved in Notch signaling pathway. MATERIALS AND METHODS: Considering the role of the pathway and its down-stream genes in proliferation, differentiation, cell cycle, and apoptosis, NOTCH1, c-Myc, and CCND1 genes were selected as target genes. Using bioinformatics studies, miR-34a, miR-449a, miR-1827, and miR-106b were selected as miRNAs targeting the above-mentioned genes. We evaluated these genes and miRNAs in T-ALL clinical samples as well as Jurkat cell line, in which NOTCH1 is overexpressed. RESULTS: Quantitative Real-Time PCR indicated that NOTCH1, c-Myc, and CCND1 were overexpressed in samples with decreased expression of miR-34a. In addition, we observed that samples with decreased expression of miR-449a showed increased expression of NOTCH1 and CCND1. Furthermore, we analyzed the expression of miR-1827 and miR-106b, which target c-Myc and CCND1, respectively. We found out that the expression of miR-1827, miR-106b, and their respective target genes were inversely correlated in 80% and 75% of the cases (r=0.8), respectively. Furthermore, in Jurkat cell line, the expression of target genes was increased while the candidate miRNAs except miR-34a were decreased. CONCLUSION: These miRNAs can be proposed as biomarkers and new therapeutic targets in T-ALL patients who have NOTCH1 overexpression.

An investigation on the expression of miRNAs including miR-144 and miR-34a in plasma samples of RET-positive and RET-negative medullar thyroid carcinoma patients.

Medullary thyroid carcinoma (MTC) is a scarce cancerous disease, originating from parafollicular C cells of the thyroid gland. MTC can be manifested as an aggressive carcinoma with metastasis, especially in sporadic forms. Mutations of the rearranged during transfection (RET) proto-oncogene occurs in all hereditary and a few somatic MTCs, so detection of RET mutations is needed for prompt and appropriate treatment. MicroRNAs (miRNAs) are noncoding regulatory RNAs. Extensive studies have done in progress or suppression of several types of cancers such as MTCs with the remarkable application as prognostic markers. Of the effective miRNAs in cancers, miR-144 and miR-34 were evaluated in our study. Blood samples of 25 RET-positive and 25 RET-negative blood samples of patients with MTC were evaluated for these miRNAs, using quantitative real-time polymerase chain reaction (RT-qPCR). Analysis of the results was performed by the 2 -ΔΔCt method, showing that miR-144 and miR-34a expression had a relative increase in patients with MTC compared with normal control samples and also in RET positives versus RET negatives. We recruited 50 out of 350 MTC plasma samples (27 female and 23 male) which were selected based on RET mutation in exon 11 (25 RET-positive and 25 RET-negative), with a mean ± SD age of 37.04 ± 1.74 years. Receiver operating characteristic (ROC) curve analysis was done to investigate the prognostic value of these miRNAs; although, they showed no significant prognostic value as MTC biomarkers in plasma samples. In conclusion, miRNAs can be used as biomarkers of cancers such as MTC; however, more studies are needed to find the best candidate miRNAs for the diagnosis of cancers.

Effect of let-7a overexpression on the differentiation of conjunctiva mesenchymal stem cells into photoreceptor-like cells.

OBJECTIVES: MicroRNAs (miRNAs) could regulate many cellular processes such as proliferation and differentiation. let-7a miRNA is one of the key regulators in the developmental transition of retinal progenitor cells into differentiated cells. Current evidence suggests that mesenchymal stem cells (MSCs) can isolate from various tissues such as bone marrow and conjunctiva. In this study, we investigated the effect of let-7a overexpression on induced differentiation of conjunctiva mesenchymal stem cells (CJMSCs) into photoreceptor-like cells. MATERIALS AND METHODS: After isolation and characterization, CJMSCs were transduced with lentiviruses containing let-7a or empty vector. The effect of let-7a overexpression on expression of photoreceptor-specific markers was evaluated by quantitative real-time PCR (RT-qPCR) after 28 and 42 days of transduction. RESULTS: The relative expression of rhodopsin and recoverin genes was evaluated by RT-qPCR in let-7a overexpressing cells, control vector transduced cells and untransduced CJMSCs (control cells). Our results indicated that following overexpression of let-7a, after 28 and 42 days of transduction, significant up-regulation in the expression of recoverin (574.7 and 43.9 folds) and rhodopsin (3334.7 and 53.1 folds) were observed, respectively. CONCLUSION: Our findings indicate that overexpression of let-7a microRNA can increase the expression of photoreceptor-specific genes in CJMSCs. Moreover, it is prospective that let-7a overexpression can use as an alternative protocol for the differentiation of mesenchymal stem cells into photoreceptors. It seems that the effect of let-7a on the differentiation of CJMSCs into photoreceptors is also time-dependent.

Expression and CpG island methylation pattern of MMP-2 and MMP-9 genes in patients with congenital factor XIII deficiency and intracranial hemorrhage.

OBJECTIVES: Congenital factor XIII (FXIII) deficiency is a rare severe bleeding disorder. Intracranial hemorrhage (ICH) is the leading cause of mortality and morbidity in FXIII deficiency. However, its pathogenesis is not well understood yet. In this study, we investigated the expression and CpG island methylation status of matrix metalloproteinase-2 (MMP-2) and MMP-9 in patients with FXIII deficiency and ICH. METHODS: Forty patients with FXIII deficiency including twenty patients with ICH, and twenty without ICH were recruited as case and control groups, respectively. Methylation status was determined by bisulfite sequencing polymerase chain reaction (PCR), and gene expression was assessed by quantitative real-time PCR. RESULTS AND DISCUSSION: We found an unmethylated pattern for both MMP-2 and MMP-9 genes in the case group. Both genes were partially methylated in the control group, while the percentage of methylated CpGs was significantly higher in MMP-9 than MMP-2 (P = 0.001). Furthermore, higher expression of MMP-9 (in both the mRNA and protein levels) was found in the case than control group (P = 0.008 and P = 0.009, respectively). On the other hand, there was no significant difference in MMP-2 expression level (neither mRNA nor protein) between the two groups (P = 0.12 and P = 0.25, respectively). CONCLUSION: Our findings indicated that MMP-9 over-expression might be related to ICH in FXIII deficiency, and gene methylation effectively regulates its expression. Future researches will expand our understanding of the pathogenesis of ICH in congenital FXIII deficiency.

Wnt pathway targeting reduces triple-negative breast cancer aggressiveness through miRNA regulation in vitro and in vivo.

Triple-negative breast cancer, devoid of estrogen (ER), progesterone (PR), and human epidermal growth factor receptor 2 (HER-2) expression, is deprived of commonly used targeted therapies. MicroRNAs (miRNAs) are undergoing a revolution in terms of potentially diagnostic or therapeutic elements. Combining computational approaches, we enriched miRNA binding motifs of Wnt pathway-associated upregulated genes. Our in-depth bioinformatics, in vitro and in vivo analyses indicated that miR-381 targets main genes of the Wnt signaling pathway including CTNNB1, RhoA, ROCK1, and c-MYC genes. The expression level of miR-381 and target genes was assessed by quantitative real-time polymerase chain reaction (RT-qPCR) in MCF-7, MDA-MB-231, and MCF-10A as well as 20 breast cancer samples and normal tissues. Luciferase reporter assay was performed. Lentiviral particles containing miR-381 were used to evaluate the effect of miR-381 restoration on cell proliferation, migration, and invasion of the invasive triple-negative MDA-MB-231 cell line and also in a mouse model of breast cancer. The expression of miR-381 was lower than that of normal cells, especially in TNBC cell line and breast tissues. Luciferase assay results confirmed that miR-381 targets all the predicted 3'-untranslated regions (3'-UTRs). Upon miR-381 overexpression, the expression of target genes declined, and the migration and invasion potential of miR-381-receiving MDA-MB-231 cells decreased. In a mouse model of triple-negative breast cancer, miR-381 re-expression inhibited the invasion of cancer cells to lung and liver and prolonged the survival time of cancer cell-bearing mice. Therefore, miR-381 is a regulator of Wnt signaling and its re-expression provides a potentially effective strategy for inhibition of TNBC.

Exosomal miRNAs from highly metastatic cells can induce metastasis in non-metastatic cells.

AIMS: Breast cancer is a high prevalence cancer among women worldwide. 15-20% of breast cancer cases are triple-negative with a poor prognosis. miRNA aberrant expression is one of the reasons of cancer development and metastasis. Exosomes are vesicles that carry cargos such as miRNAs to other cells. Therefore, we hypothesized that miRNAs transported by exosomes to other cells can induce malignant transformation. MATERIALS AND METHODS: We extracted exosomes from highly metastatic MDA-MB-231 cells and characterized them using Dynamic light scattering, scanning and transmitting electron microscopy as well as western blot. Then, we treated non-metastatic MCF-7 cells with the exosomes. Afterwards, we evaluated exosome uptake by MCF-7 cells using PHK67 staining. Finally, we used soft agar colony formation, migration, and invasion assays to explore any increase in/induction of metastatic behavior of exosome-treated MCF-7 cells. KEY FINDINGS: Our result indicated that the particles extracted from MDA-MB-231 cells' supernatant were actually exosomes. PKH67 staining and confocal microscopy showed that the exosomes were actively taken up by MCF-7 cells. Treatment of MCF-7 cells with the exosomes resulted in increased ability of MCF-7 cells to grow independent of anchorage. In addition, migration and invasion capacity of exosome-treated MCF-7 cells increased in a dose-dependent manner. SIGNIFICANCE: Along with our previous study, we here indicate that highly metastatic MDA-MB-231 cells' exosomes and exosomal miRNAs may induce malignant transformation in non-metastatic MCF-7 cells, thus introducing a novel route of cancer development and metastasis.

Evaluation of exosomal miR-9 and miR-155 targeting PTEN and DUSP14 in highly metastatic breast cancer and their effect on low metastatic cells.

Breast cancer is one of the most prevalent cancers in women. Triple-negative breast cancer consists 15% to 20% of breast cancer cases and has a poor prognosis. Cancerous transformation has several causes one of which is dysregulation of microRNAs (miRNAs) expression. Exosomes can transfer miRNAs to neighboring and distant cells. Thus, exosomal miRNAs can transfer cancerous phenotype to distant cells. We used gene expression omnibus (GEO) datasets and miRNA target prediction tools to find overexpressed miRNA in breast cancer cells and their target genes, respectively. Exosomes were extracted from MDA-MB-231 and MCF-7 cells and characterized. Overexpression of the miRNAs of MDA-MB-231 cells and their exosomes were analyzed using quantitative Real-time PCR. The target genes expression was also evaluated in the cell lines. Luciferase assay was performed to confirm the miRNAs: mRNAs interactions. Finally, MCF-7 cells were treated with MDA-MB-231 cells' exosomes. The target genes expression was evaluated in the recipient cells. GSE60714 results indicated that miR-9 and miR-155 were among the overexpressed miRNAs in highly metastatic triple negative breast cancer cells and their exosomes. Bioinformatic studies showed that these two miRNAs target PTEN and DUSP14 tumor suppressor genes. Quantitative Real-time PCR confirmed the overexpression of the miRNAs and downregulation of their targets. Luciferase assay confirmed that the miRNAs target PTEN and DUSP14. Treatment of MCF-7 cells with MDA-MB-231 cells' exosomes resulted in target genes downregulation in MCF-7 cells. We found that miR-9 and miR-155 were enriched in metastatic breast cancer exosomes. Therefore, exosomal miRNAs can transfer from cancer cells to other cells and can suppress their target genes in the recipient cells.