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Human induced pluripotent stem cells (hiPSCs) are a type of pluripotent stem cells artificially derived from an adult somatic cell (typically human fibroblast) by forced expression of specific genes. In recent years, different feeders like inactivated mouse embryonic fibroblasts (MEFs), human dermal fibroblasts (HDFs), and feeder free system have commonly been used for supporting the culture of stem cells in undifferentiated state. In the present work, the culture of hiPSCs and their characterizations on BD Matrigel (feederand serum-free system), MEF and HDF feeders using cell culture methods and molecular techniques were evaluated and compared. The isolated HDFs from foreskin samples were reprogrammed to hiPSCs using gene delivery system. Then, the pluripotency ability of hiPSCs cultured on each layer was determined by teratoma formation and immunohistochemical staining. After EBs generation the expression level of three germ layers genes were evaluated by Q-real-time PCR. Also, the cytogenetic stability of hiPSCs cultured on each condition was analyzed by karyotyping and comet assay. Then, the presence of pluripotency antigens were confirmed by Immunocytochemistry (ICC) test and alkaline phosphatase staining. This study were showed culturing of hiPSCs on BD Matrigel, MEF and HDF feeders had normal morphology and could maintain in undifferentiated state for prolonged expansion. The hiPSCs cultured in each system had normal karyotype without any chromosomal abnormalities and the DNA lesions were not observed by comet assay. Moreover, upregulation in three germ layers genes in cultured hiPSCs on each layer (same to ESCs) compare to normal HDFs were observed (p<0.05). The findings of the present work were showed in stem cells culturing especially hiPSCs both MEF and HDF feeders as well as feeder free system like Matrigel are proper despite benefits and disadvantages. Although, MEFs is suitable for supporting of stem cell culturing but it can animal pathogens transferring and inducing immune response. Furthermore, HDFs have homologous source with hiPSCs and can be used as feeder instead of MEF but in therapeutic approaches the cells contamination is a problem. So, this study were suggested feeder free culturing of hiPSCs on Matrigel in supplemented media (without using MEF conditioned medium) resolves these problems and could prepare easy applications of hiPSCs in therapeutic approaches of regenerative medicine such as stem-cell therapy and somatic cell nuclear in further researches.

Human dermal fibroblasts (HDFs) are a potential source of somatic cells for genetic manipulation and tissue engineering. Confirmation of cytogenetic stability of these cells is an essential step for cell nuclear transfer and generation of a suitable and functional induced pluripotent stem cells line. HDF cells were isolated and cultured from human foreskin samples. Cytogenetic stability of these cells was evaluated in early (3-4) and late (10-15) passages using karyotype test and alkaline comet assay techniques. HDF cells in early and late passages showed normal karyotype but by comet assay abnormality and DNA damages in late passages of HDFs were observed. Also, the parameters of alkaline comet assay in early passages of HDFs compared with late passages and positive control groups more significantly were different (p < 0.05). These findings indicate that single-strand breaks or DNA damage after many passages may have occurred in HDF cells. Our results demonstrate that only early passages of HDF cells maintain cytogenetic stability and are good candidates for gene reprogramming. In conclusion, karyotype testing alone can not be used for detection of all signs of cytogenetic abnormality and DNA damages of cells. So, for precise evaluation of DNA damage and cytogenetic instability of fibroblast cells comet assay and karyotype techniques could complement each other.

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Our finding shows that EA can be considered as a potent agent that decreases cell proliferation through a reduction of phosphorylated STAT3, ERK, and AKT cellular signaling proteins.

Background:In this study, we demonstrated the effects of the Gallic Acid (GA) molecule on the prostate cancer cells line PC3 using the comet assay (Alkaline electrophoresis) technique and its effects on some important apoptotic factors including BAD (Bcl-2-Associated Death promoter), BAK (Bcl-2 homologous Antagonist/Killer), and BIM (Bcl-2-like protein 11) via simulation analysis by using the Auto Dock and Gromacs software.Methods: Following the MTT assay on the PC3 cells, and determining IC50, we used three concentrations of GA to around IC50 to treat PC3 cells. 100 comet pictures were obtained by alkaline electrophoresis and have been analysed with the CASP version 1.2.2 software; all the results were thereafter analysed by the SPSS version 21 statistical software.Results: The IC50 value for GA was determined to be 35 µM. The ratio of tail to head in alkaline electrophoresis for the three concentrations below the IC50 of GA in 25, 30, and 35 µM were measured as 24.7 (2.7), 44.5 (1.8), and 57.3 (1.3) percent, respectively. The results of the preapoptotic factors (BAD, BAK, and BIM) in the performed simulation in the absence and presence of GA showed that the GA protein causes the structural instability in the BAD protein, and the effect of GA can be explained by the creation of hydrogen bonds with proteins.Conclusion: GA is a polyphenol compound in plants that can suppress cell growth and induce apoptosis in PC3 cells in prostate cancer in the range of IC50 concentrations. The apoptotic properties of GA induce pre-apoptotic factors.

Background:The novel Coronavirus (COVID-19) has spread rapidly across the globe and has involved more than 213 countries and territories. Due to a lack of effective therapy or vaccine, urgent and concerted efforts are needed to identify therapeutic targets and medications. COVID-19 main protease represents a major target for drug treatment to inhibit viral function.Objectives: The present study sought to evaluate medicinal plant compounds as potential inhibitors of the COVID-19 main protease using molecular docking and molecular dynamic analysis. Methods:The PDB files of COVID-19 main protease and some medicinal plant compounds were retrieved from the Protein Data Bank (http://www.rcsb.org) and Pubchem server, respectively. The Gromacs software was used for simulation studies, and molecular docking analysis was done using Autodock 4.2. The COVID-19 main protease simulation, compared with some phytochemicals docked to the COVID-19 main protease, were analyzed.Results: Glabridin, catechin, and fisetin had the greatest tendency to interact with the COVID-19 main protease by hydrogen and hydrophobic bonds. Docking of these phytochemicals to COVID-19 main protease led to an increase in the radius of gyration (Rg), decrease in the Root mean square fluctuation (RMSF), and induced variation in COVID-19 main protease secondary structure. Conclusion:The high tendency interaction of glabridin, catechin, and fisetin to COVID-19 main protease induced conformational changes on this enzyme. These interactions can lead to enzyme inhibition. This simulated study indicates that these phytochemicals may be considered as potent inhibitors of the viral protease; however, more investigations are required to explore their potential medicinal use.

Gastric cancer ranks second cause of cancer death worldwide after lung cancer. Its etiology is heterogeneous and genetic factors including protooncogenes and tumor suppressor genes always contribute to the progression of cancer. The TP53 tumor suppressor gene has a broad role in genomic stability and DNA repair. The aim of this study was to determine the TP53 gene mutations in gastric cancer specimens in Chaharmahal Va Bakhtiari province of Iran. In this descriptive-lab based study, we investigated the promoter and exons of TP53 gene mutations in 38 paraffin-embedded gastric cancer specimens. DNA was extracted following a standard phenol-chloroform protocol. The TP53 gene mutations were determined using PCR-SSCP & PCR-RFLP procedures. The present study revealed no TP53 gene mutation in the promoter and exons in the gastric cancer subjects studied. While TP53 gene mutations have been reported as the most frequent genetic alterations and are found in about 50% of the human malignancies, no mutation was detected in this study. This may be due to mutations in other related genes in the same pathway or epigenetic factors.