mehdi shakibaie

The rate at which cancer develops is significantly influenced by angiogenesis. The multifunctional effects of curcumin on breast cancer cells were examined in this study at the level of gene expression. Using the MTT assay, the cytotoxicity impact of curcumin was assessed. Real-time PCR was used to quantify the expression of a few genes involved in the angiogenesis, and apoptosis of MDA-231-MB cells. The results indicated that curcumin inhibited cancer proliferation in a dose- and time-dependent manner. The IC50 curcumin was about 40 µM and 15 µM after 48 h, and 96 h culture time respectively. Also, the quantitative analysis of gene expression showed that curcumin suppressed angiogenesis by decreasing the expression of VEGF and induced apoptosis by upregulation of Bax and down-regulation of Bcl-xl at the initial dose of toxicity concentration.

Nanobiotechnology has provided promising novel diagnostic and therapeutic strategies which capable to create a broad spectrum of nano-based imaging agents and medicines for human administrations. Several studies have demonstrated that the surface of nanomaterials is immediately coated with suspended proteins after contact with plasma or other biological fluids to form protein corona-nanoparticle complexes. Cells react after exposure with these complexes. since, the biological fate and functions of nanomaterials are determined by physiological responses to protein -nanoparticle complexes in this article, we aimed to review some studies about the effects of the protein profiles and physicochemical characteristics of nanoparticles in the biological environment on the formation of protein corona and subsequent the biological responses upon exposure to nanoparticles. Also, some used methods for of protein corona analysis has been reviewed. It has been shown that the biological impacts of protein corona may be both constructive and/or destructive in the biomedical applications of nanomaterials. The protein corona–cell interactions can facilitate targeted delivery and cellular absorption of therapeutic nanomaterials and also, they mitigate the unfavorable cytotoxic effects of nanoparticles. On the other hand, these interactions may cause rapid clearance of nanoparticles from the body as well as the activation of undesirable inflammatory responses. Hence, the study of the formation mechanism and biological effects of protein corona plays an important role in the design of nanoparticles with specific physicochemical properties proportional with their intended biological activity.

Codon optimization has been considered as a powerful strategy to increase the expression level of protein therapeutics in mammalian cells. As an empirical approach to study the effects of the codon usage and GC content on heterologous gene expression in suspension adapted Chinese hamster ovary (CHO-s) cells, we redesigned the recombinant human interferon beta (rhIFN-β) gene based on the codon preference of the CHO cell in a way to increase the GC content in the third position of each codon.

The nucleotide sequence of the codon-optimized rhIFN-β was synthesized in parallel with the wild-type and expressed transiently in CHO-s cells using Epstein-Bar virus (EBV)-based expression system. The protein expression of the rhIFN-β by codon-optimized and wild-type genes were quantified using ELISA test.

The results indicated a 2.8-fold increase in the expression level of the biologically active form of the rhIFN-β by codon-optimized sequence.

These results shed light on the capability of codon optimization to create a stable CHO cell for scaling up the production of recombinant therapeutics such as rhIFN-β. 

Expansion and differentiation of stem cells relies on the soluble materials as well as the physical conditions of their microenvironment. Several methods have been studied in attempt to enhance the growth and differentiation rates of different adult stem cells extracted from different sources.
The purpose was to improve the three-dimensional (3D) culture condition of the semi-permeable polymeric beads for encapsulation of the human adipose-derived mesenchymal stem cells (hADSCs) by modifying the ratio of the alginate-gelatin composition.
Following isolation and characterization of hADSCs by flow cytometry and their functional differentiation, encapsulation in the alginate and alginate/gelatin compositions were performed. Moreover, the stability, swelling, size frequency, growth kinetics, and cytotoxicity of the beads were measured to meet proper condition in the designed experimental and control culture conditions. Finally, the growth rates of the cells in different experimental groups and control were measured and analyzed statistically.
Viability decreased in 2 and 3 percent alginate once compared to 1% alginate in beads (p£0.05). Moreover swelling of the beads in the alginate/gelatin compositions (50:50 and 70:30) were higher than the pure alginate beads (p£ 0.05). Finally, the cell growth rate in alginate/gelatin (50:50) beads was significantly higher than alginate and alginate/gelatin (70:30) beads (p£0.05).
These findings suggested for the first time that the composite of alginate/gelatin beads with the ratio of 50:50 might provide a suitable culture condition for the encapsulation and in vitro expansion of the hADSCs.

Piwil2, a member of Ago/Piwi gene family containing Piwi and PAZ domains, has been shown to be ectopically expressed in different cancer cells, especially its remarkable expression in cancer stem cells (CSCs), and is also known to be essential for germ line stem cell self-renewal in various organisms. The hypothesis that CSC may hold the key to the central problem of clinical oncology and tumor relapse leads to more anticancer treatment studies. Due to emerging controversies and extreme difficulties in studying of CSC, like the cells using in vivo models, more attempts have expended to establish different in vitro models. However, the progress was slow owing to the problems associated with establishing proper CSC cultures in vitro. To overcome these difficulties, we prompted to establish a novel stable cell line over-expressing Piwil2 to develop a potential proper in vitro CSC model. In this experimental study, mouse embryonic fibroblasts (MEFs) were isolated and electroporated with a construct containing Piwil2 cDNA under the control of the cytomegalovirus promoter (CMV). Stable transfectants were selected, and the established MEF-Piwil2 cell line was characterized and designated as CSC-like cells using molecular markers. Functional assays, including proliferation, migration, and invasion assays were performed using characterized CSC like cells in serum-free medium. Additionally, MEF-Piwil2 cell density and viability were measured by direct and indirect methods in normoxic and hypoxic conditions. The results of reverse transcriptase-polymerase chain reaction (RT-PCR), western blot, and immunocytochemistry revealed an overexpression for Piwil2 in the transfected Piwil2 cells both in the RNA and protein levels. Furthermore, analysis of the kinetic and stoichiometric parameters demonstrated that the specific growth rate and the yield of lactate per glucose were significantly higher in the MEF-Piwil2 group compared to the MEF cells (ANOVA, p<0.05). Also, analysis of functional assays including migration and invasion assays demonstrated a significantly higher number of migrated and invaded cells in the MEF-Piwil2 compared to that of the MEF cells (ANOVA, p<0.05). The MEF-Piwil2 cells tolerated hypoxia mimetic conditions (CoCl2) with more than 95% viability. According to the molecular and functional studies, it has been realized that Piwil2 plays a key role(s) in tumor initiation, progression and metastasis. Therefore, Piwil2 can be used not only as a common biomarker for tumor, but also as a target for the development of new anticancer drug. Finally, the main outcome of our study was the establishment of a novel CSC-like in vitro model which is expected to be utilized in understanding the complex roles played by CSC in tumor maintenance, metastasis, therapy resistance or cancer relapse.