Crocin suppresses multidrug resistance in MRP overexpressing ovarian cancer cell line

Background Crocin, one of the main constituents of saffron extract, has numerous biological effects such as anti-cancer effects. Multidrug resistance- associated proteins 1 and 2 (MRP1 and MRP2) are important elements in the failure of cancer chemotherapy. In this study we aimed to evaluate the effects of crocin on MRP1 and MRP2 expression and function in human ovarian cancer cell line A2780 and its cisplatin-resistant derivative A2780/RCIS cells. Methods The cytotoxicity of crocin was assessed by the MTT assay. The effects of crocin on the MRP1 and MRP2 mRNA expression and function were assessed by real-time RT-PCR and MTT assays, respectively. Results Our study indicated that crocin reduced cell proliferation in a dose-dependent manner in which the reduction in proliferation rate was more noticeable in the A2780 cell line compared to A2780/RCIS. Crocin reduced MRP1 and MRP2 gene expression at the mRNA level in A2780/RCIS cells. It increased doxorubicin cytotoxicity on the resistant A2780/RCIS cells in comparison with the drug-sensitive A2780 cells. Conclusion Totally, these results indicated that crocin could suppress drug resistance via down regulation of MRP transporters in the human ovarian cancer resistant cell line

Nanolipoparticles-mediated MDR1 siRNA delivery reduces doxorubicin resistance in breast cancer cells and silences MDR1 expression in xenograft model of human breast cancer

Objective(s): P-glycoprotein (P-gp) is an efflux protein, the overexpression of which has been associated with multidrug resistance in various cancers. Although siRNA delivery to reverse P-gp expression may be promising for sensitizing of tumor cells to cytotoxic drugs, the therapeutic use of siRNA requires effective carriers that can deliver siRNA intracellularly with minimal toxicity on target cells. We investigated a special class of PEGylated lipid-based nanoparticles (NP), named nanolipoparticles (NLPs), for siRNA- mediated P-gp downregulation. Materials and Methods: NLPs were prepared based on low detergent dialysis method. After characterization, we evaluated the effect of NLPs on siRNA delivery, and P-gp downregulation compared to oligofectamineTM (OFA) in vitro and in vivo. Results: Our results showed a significant decrease in P-gp expression and subsequent enhancement of chemosensitivity to doxorubicin in vitro. Although the effectiveness of NLPs for in vitro siRNA delivery compared to OFA was limited, the results of in vivo studies showed noticeable effectiveness of NLPs for systemic siRNA delivery. siRNA delivery using NLPs could downregulate MDR1 in tumor cells more than 80%, while OFA had a reverse effect on MDR1 expression in vivo. Conclusion: The results indicated that the prepared NLPs could be suitable siRNA delivery systems for tumor therapy

The effects of crocetin, extracted from saffron, in chemotherapy against the incidence of multiple drug resistance phenotype

Objective(s): Crocetin, one of the main substances of saffron extract, has anti-cancer effects. Drug resistance proteins (e.g. MRP1 and MRP2) are important reasons for the failure of cancer therapy. We intended to investigate the efficacy of crocetin on MRP1 and MRP2 activity in human ovarian cisplatin-resistant carcinoma cell line (A2780-RCIS).Materials and Methods: The cytotoxic effect of crocetin was evaluated by the MTT assay. The efficacy of crocetin on MRP1 and MRP2 expression at mRNA level was studied by real-time RT-PCR. The effect of crocetin on the activity of MRP transporters was determined by drug efflux assay.Results: Crocetin decreased cell proliferation in the A2780 (IC50: 183±7 µM) and A2780-RCIS (IC50: 316±9 µM). Crocetin decreased the expression level of MRP1 (22±2 %) and MRP2 (48±8 %) in A2780-RCIS and inhibited MRP pumps function directly in A2780 (44±1 %) and A2780-RCIS (88±10 %) and indirectly in A2780 (32±2 %) and A2780-RCIS (48±15 %) respectively. Conclusion: Our findings showed that crocetin could quench drug resistance through modulation of MRP transporters in the drug resistant human ovarian cancer cells

Whole-genome sequence of <i>Pseudomonas fluorescens</i> EK007-RG4, a promising biocontrol agent against a broad range of bacteria, including the fire blight bacterium <i>Erwinia amylovora</i>

Here, we report the first draft whole-genome sequence of Pseudomonas fluorescens strain EK007-RG4, which was isolated from the phylloplane of a pear tree. P. fluorescens EK007-RG4 displays strong antagonism against Erwinia amylovora, the causal agent for fire blight disease, in addition to several other pathogenic and non-pathogenic bacteria

Inhibition of Akt phosphorylation attenuates resistance to TNF-α cytotoxic effects in MCF-7 cells, but not in their doxorubicin resistant derivatives

Objective(s): Acquisition of TNF-α resistance plays role in the onset and growth of malignant tumors. Previous studies have demonstrated that MCF-7 cell line and its doxorubicin resistant variant MCF-7/Adr are resistant against the cytotoxic effects of TNF-α. In this study, we investigated the role of Akt activation in resistance of MCF-7 and MCF-7/Adr against TNF-α cytotoxicity. Materials and Methods: The role of Akt activation in TNF-α cytotoxicity was investigated by MTT cell viability assay following treatment of the cells with the chemical inhibitor of Akt activation with or without TNF-α treatment. Phosphorylation of Akt at Ser473 before and after 72 hr TNF-α treatment  was also determined by western blot. Results: TNF-α treatment led to enhancement of Akt Ser473 phosphorylation. Treatment of MCF-7 cells with TNF-α along with Akt-inhibitor agent, tricribine, attenuated Akt Ser473 phosphorylation and sensitized these cells to the cytotoxic effects of TNF-α in a dose and time dependent manner while tricribine treatment did not cause any significant cytotoxicity in MCF-7/Adr cells alone or in combination with TNF-α. Conclusion: These results demonstrate that Akt phosphorylation plays pivotal role in the resistance of MCF-7 cells against TNF-α-induced cytotoxicity while it might play no significant role in the resistance of MCF-7/Adr cells against TNF-α

Estrogenic activity of Elaeis guineensis leaf

To assess the estrogenic activities of Oil Palm Fronds (Elaeis guineensis) extracts a vaginal cytology assay in normal and ovariectomized rats were used. The alcoholic extract of Elaeis guineensis (OPLME) was administered orally to adult normal cycling and ovareiectomized Sprague/Dawley rats. Bilaterally ovariectomized rats were divided into four groups (n = 8) receiving different treatments, consisting of vehicle, 150 and 300 mg/kg body weight OPLME and Premarin (conjugated estrogens) at a dose of 2.5 mg/kg body weight. Estrogenic activity was assessed by taking percentage vaginal cornification and uterine wet weight as parameters of assessment. The OPLME resulted in an irregular estrous cycle with lengthened estrus in dose dependent manner. Restoration of normal estrous cycles after withdrawal of treatment indicates the reversible effect of alcoholic extract in normal rats. OPLME administration produced statistically significant (P < 0.001), 2.54/fold increase in circulating 17 β /estradiol levels. OPLME showed a significant increase in percentage vaginal cornification, and uterine wet weight (P < 0.001), compared to the control in a dose dependent manner in ovariectomized rat. This estrogenic property of OPLME may be a possible explanation for the OPLME effects on the blood lipid profile. The estrogenic activity shown by OPLME can be attributed to the presence of flavonoids and phenolic compounds

Immunogenicity and antitumor activity of the superlytic λF7 phage nanoparticles displaying a HER2/neu-derived peptide AE37 in a tumor model of BALB/c mice

The final publication is available at Elsevier via http://dx.doi.org/10.1016/j.canlet.2018.03.030 © 2018. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/Phage display technique has been increasingly researched for vaccine design and delivery strategies in recent years. In this study, the AE37 (Ii-Key/HER-2/neu 776–790) peptide derived from HER2 (human epidermal growth factor receptor protein) was used as a fused peptide to the lambda phage (λF7) coat protein gpD, and the phage nanoparticles were used to induce antitumor immunogenicity in a TUBO model of breast cancer in mice. Mice were immunized with the AE37 peptide displaying phage, λF7 (gpD::AE37) every 2-week intervals over 6-weeks, then the generated immune responses were evaluated. An induction of CTL immune response by the λF7 (gpD::AE37) construct compared to the control λF7 and buffer groups was observed in vitro. Moreover, in the in vivo studies, the vaccine candidate showed promising prophylactic and therapeutic effects against the HER2 overexpressing cancer in BALB/c mice.Mashhad University of Medical Sciences, Mashhad, Iran bach (MUMS GN: 922610)NSERC, Canada (NSERC GN: 214684

Detection and Characterization of β-Lactam Resistance in Bacillus cereus PTCC 1015

In the present study, detection, isolation, and characterization of β-lactamases from Bacillus cereus PTCC 1015 were investigated. B. cereus was inoculated in nutrient broth containing ampicillin (50 μg.ml−1) for 24 h (35°C, 200 rpm). Activity measurements were carried out against ampicillin (0.1 mg.ml−1) and cephalexin (0.08 mg.ml−1) by a spectrophotometric method at different conditions (pH 6–10, temperatures 2545°C).Maximum penicillinase and cephalosporinase activity was observed at pH 7. The optimized temperatures for penicillinase and cephalosporinase activity were 30 and 40°C, respectively. At the above conditions, maximum enzymatic activity was calculated as 0.89 ± 0.014 and 0.037 ± 0.001 units against ampicillin and cephalexin

Studies On Bioactive Glass

International audienc