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Studies have shown that simulated microgravity (SMG) affects tumor cell growth and metastasis. However, the underlying molecular basis is still not known. In recent years, due to the high expression of CD44 in invasive basal breast tumors, it has been the subject of many studies. The aim of present study was to investigate the gene expression of CD44 in MDA-MB-231cell line of breast cancer in microgravity conditioncell line was proliferated under normal gravity and microgravity (1 and 3 days) using 2-D clinostat. Gene expression was measured using real-time PCR technique. SMG increased gene expression (100%) after 1 day and decreased it (15%) during 3 days in comparison to the control samples. It seems that the response of cancer cells to microgravity is time dependent and simulated microgravity treatment for 3 days may have a positive effect on cancer characteristics of MDA-MB-231 cell line in order to decrease the expression of CD44.

Background and Objective: Breast cancer accounts for about onethird of all cancers in women. Behind lung cancer, it is the second leading cause of cancer deaths in this gender group. In traditional medicine, Euphorbia (E.) microsciadia (Boiss) is a plant used for cancer treatment. Therefore, the main purpose of this study was to determine the effect of E. microsciadia extract on elimination of tumor cells and expression of cytokines in breast cancer MDA-MB- 231 cell line. Materials and Methods: Cell culture was performed in Dulbecco’s Modified Eagle Medium (DMEM); supplemented with 10% fetal bovine serum (FBS), penicillin (1IU/ml), and streptomycin (1μg/ml) at 37°C, with 5% CO2 and 95% humidity. The effect of E. microsciadia extract on the viability of MDA-MB-231 cells was then evaluated by MTT assay. To estimate the expression level of the mRNA of IL-1β, IL-6, IL-8, IL-10, IL-17A, TGF-β1, and INF-γ following MDA-MB-231 cell line treatment with the plant extract, the RNA was extracted using TRIzol solution for cDNA synthesis. The mRNA expression level was subsequently measured in the samples by TaqMan real-time polymerase chain reaction (PCR) technique. The expression of cytokines in both groups of extract treatment and control was ultimately analyzed via Mann-Whitney U test. Results: After 24 and 48 h, the IC50 values for the E. microsciadia extract were determined at 278.30 and 238.20μg/ml, respectively. Besides, the extract showed evidence of anti-proliferative effects on the MDA-MB-231 cell line in a dose- and time-dependent manner. Moreover, the expression levels of INF-γ, IL-8, and IL-1β had significantly increased 24 and 48 h after being treated with E. microsciadia extract. The expression level of TGF-β1, IL-6, IL-10, and IL-17A had correspondingly augmented and decreased after 24 and 48 h of treatment; respectively. Conclusion: The E. microsciadia extract may be used as a tool to manipulate expression of cytokine genes and to ultimately control cell growth and proliferation, which is of utmost importance for molecular and cellular studies in cancer therapy. [ABSTRACT FROM AUTHOR]

Introduction: Gravity is one of the most important forces exposed to the organisms on the earth which affects the cells, molecules and thus the entire of organism. The purpose of this study is to investigate the effect of the simulated microgravity on the changes of RKIP metastasis suppressor gene expression on MDA-MB-231 breast cancer cell line.Materials and Methods: In order to impose microgravity state, cancer cells were placed on clinostat for one and three days. Then RNA was extracted from the cells and RKIP gene expression changes were evaluated by qReal time PCR.Results: The findings showed that the microgravity during one day reduced the RKIP expression level, but with continuing up to three days, the expression returned to the control level.Conclusion: By optimizing the duration of microgravity, it can be likely observed the significant effects on the RKIP gene expression changes and so that useful steps can be taken to discover the cancer mechanisms and its treatment.

Introduction: Multi-drug resistance (MDR) might be acquired by the cancer cells during chemotherapy, and ATPbinding cassette (ABC) transporters play a significant role in MDR. Interferon-γ (IFN-γ) and IFN-β can inhibit cancer cell proliferation; however, the effects and mechanism of these cytokines on growth and MDR are still unclear. Methods and Materials: Using the MDA-MB-231 cell line, we assessed the effects of 20, 100, and 500 IU/ml of IFN-γ and IFN-β, alone or in combination, on cell viability by the methyl thiazolyl tetrazolium (MTT) assay, and then we performed the Uptake and Efflux experiment to evaluate the effect of these IFNs on the cell resistance. Then, using quantitative real-time PCR, we evaluated changes in the expression of ABCB1, ABCC1, and ABCG2 mRNA levels. Results: We discovered that IFN-γ and IFN-β may both reduce viability, either alone or in combination. The combination of IFNs also displayed synergistic responses, particularly when utilizing equivalent dosages of 500 or 100 IU/ml. The combination of IFN-γ and IFN-β resulted in a significant increase in doxorubicin accumulation and down-regulation of the ABCC1 gene at the mRNA level. Conclusion: Our study suggested that equal doses of IFN-γ and IFN-β in combination may result in potentiated responses against cancer, especially when combined with chemotherapy agents. [ABSTRACT FROM AUTHOR]

Introduction: Antimicrobial peptides (AMPs) are compounds with antimicrobial properties that are studied widely due to the development of resistance of pathogenic bacteria to antibiotics. In the present study, the toxicity and antimicrobial effects of two natural monomeric peptides (S3 and S∆3) were compared with S3-S∆3 hybrids and S3 tetramers. Material & Methods: Protein hybrids (S∆3S3-2mer-GS) S3-S∆3 and tetramer protein S3 (S3-4mer-GS) were expressed in E. coli. BL21 (DE3). Following that, the presence of mutant peptides was confirmed, and their antimicrobial activity was compared and evaluated with S3 and S∆3 monomers. Finally, the toxicity of tetramer and hybrid made on the MDA-MB-231 cell line was evaluated and compared. Findings: The toxicity of the hybrid was slightly increased, compared to the tetramer for eukaryotic cells; however, this increase was negligible at the active concentration of this protein. Cell survival for hybrids was lower for S3 and SΔ3; nonetheless, cell survival for each sequence decreased with increasing time. Furthermore, the inhibition of hybrid microbial growth was improved and compared with tetramer and S3-SΔ3. It was found that an increase in the positive charge of the hybrid protein did not have a toxic effect on the host bacteria. Discussion & Conclusion: Due to the appropriate expression and increased antimicrobial activity and negligible cytotoxicity, the hybrid peptide S3-S∆3 and tetramer S3 can be considered an effective production strategy to obtain AMPs.

Introduction: The study of the effects of synthetic peptides with antibacterial properties can provide more effective antibiotics. This study designed, expressed, and investigated the Sushi 3 tetramer peptide. Subsequently, it was compared in terms of changing antibacterial properties with another Sushi3 tetramer peptide the aspartic acid and proline amino acids of which were replaced with glycine and serine amino acids. Material & Methods: First, the mentioned Sushi3 tetramer peptide sequences were designed, constructed, and named Mer1 and Mer 2, respectively, and cloned separately into plasmid pET-26b (+) and finally transferred to E.coli BL21 host (DE3). After the expression of the peptides, the presence of peptides was confirmed by SDS-PAGE and Western blotting. Afterward, the antimicrobial activity of Mer1 and Mer 2 was evaluated and compared. Finally, the toxicity of the two tetramers made on the MDA-MB-231 cell line was evaluated and compared. Findings: Mer1 and Mer 2 had similar protein expression, and the toxic effect of both peptides on the cell line was not significantly different. however, Mer 2 had more effective antimicrobial effects than Mer1 at the same concentrations. Discussion & Conclusion: Evaluation of the effect of amino acid replacement with less negatively charge on increasing the antimicrobial activity of peptides is a suitable strategy. The above results increase the possibility of designing and producing antimicrobial peptides against antibiotic-resistant strains as the next generation of antibiotics.