Comparison of Periplasmic and Cytoplasmic Expression of Bovine Enterokinase Light Chain in E. coli

The Protein Journal - Enterokinase enzyme is widely used in production of recombinant proteins. This enzyme is isolated from the intestine and recognizes a specific cleavage site...     

Circulating myeloid-derived suppressor cells: An independent prognostic factor in patients with breast cancer

Evading immune destruction is a hallmark of cancer. Myeloid-derived suppressor cells (MDSCs), a heterogeneous population of myeloid immune cells, are thought to foster the establishment of an immunosuppressive tumor microenvironment, but it remains unclear how. This study aims to determine the levels of circulating MDSCs and their subpopulations and test their immunosuppressive functions in patients with breast cancer (BC). We analyzed the fractions of MDSCs in freshly isolated peripheral blood mononuclear cells of patients with BC and healthy donors using flow cytometry. Circulating MDSCs were further phenotyped using fluorescently labeled antihuman monoclonal antibodies. Coculture experiments revealed the effects of MDSCs on CD3⁺ T cell response. Moreover, we correlated circulating MDSC levels with clinicopathological features of patients with BC. We show that the fraction of HLA-DR ^– CD33 ⁺ MDSCs in peripheral blood is about 10-fold higher in patients with BC than in healthy control individuals. The levels of all MDSC subpopulations, including monocytic and granulocytic MDSCs, are significantly elevated. Coculture experiments of purified HLA-DR ^– CD33 ⁺ MDSCs and CD3 ⁺ T cells demonstrate that T cell proliferation is more effectively inhibited by BC patient-derived MDSCs than by healthy control MDSCs. Moreover, increased circulating MDSC levels robustly associate with advanced BC stage and positive lymph node status. By being more abundant and more effective T cell suppressors, BC patient-derived circulating MDSCs exert a dual immunosuppressive effect. Our findings pave the way to develop novel diagnostic and immunotherapeutic strategies, aimed at detecting and inhibiting MDSCs in patients with BC.     

CTNNBIP1 downregulation is associated with tumor grade and viral infections in gastric adenocarcinoma

Gastric cancer is a life-threatening disease; resulting from interaction among genetic, epigenetic, and environmental factors. Aberrant dysregulation and methylation changes in Wnt/β-catenin signaling downstream elements are a prevalent phenomenon encountered in gastric tumorigenesis. Also, viral infections play a role in gastric cancer development. CTNNBIP1 (β-catenin interacting protein 1) gene is an antagonist of Wnt signaling which binds to the β-catenin molecules. The CTNNBIP1 function as tumor suppressor gene or oncogene in different types of cancer is controversial. Moreover, its function and regulatory mechanisms in gastric cancer progression is unknown. In the present study, we examined CTNNBIP1 gene expression, the methylation status of the regulatory region of the gene, and their association with Epstein–Barr virus (EBV), and cytomegalovirus (CMV) and Helicobacter pylori infections in human gastric adenocarcinoma tissues in comparison with their adjacent nontumoral tissues. Our data revealed a significant downregulation of CTNNBIP1 in gastric tumors. Female patients showed lower level of CTNNBIP1 than males (p < 0.05). Also, decreased expression of CTNNBIP1 was markedly associated with well-differentiated tumor grades (p < 0.05). No methylation change was observed between tumoral and nontumoral tissues. Additionally, CTNNBIP1 down regulation was significantly associated with CMV infection (p < 0.05). In the absence of EBV infection, lower expression of CTNNBIP1 was observed. There was no association between H. pylori infection and CTNNBIP1 expression. Our findings revealed the tumor suppressor role for CTNNBIP1 in gastric adenocarcinoma. Interestingly, EBV and CMV infections modulate CTNNBIP1 expression.     

Epigenetic-based therapy for colorectal cancer: Prospect and involved mechanisms

Epigenetic modifications are heritable variations in gene expression not encoded by the DNA sequence. According to reports, a large number of studies have been performed to characterize epigenetic modification during normal development and also in cancer. Epigenetics can be regarded more widely to contain all of the changes in expression of genes that make by adjusted interactions between the regulatory portions of DNA or messenger RNAs that lead to indirect variation in the DNA sequence. In the last decade, epigenetic modification importance in colorectal cancer (CRC) pathogenesis was demonstrated powerfully. Although developments in CRC therapy have been made in the last years, much work is required as it remains the second leading cause of cancer death. Nowadays, epigenetic programs and genetic change have pivotal roles in the CRC incidence as well as progression. While our knowledge about epigenetic mechanism in CRC is not comprehensive, selective histone modifications and resultant chromatin conformation together with DNA methylation most likely regulate CRC pathogenesis that involved genes expression. Undoubtedly, the advanced understanding of epigenetic-based gene expression regulation in the CRC is essential to make epigenetic drugs for CRC therapy. The major aim of this review is to deliver a summary of valuable results that represent evidence of principle for epigenetic-based therapeutic approaches employment in CRC with a focus on the advantages of epigenetic-based therapy in the inhibition of the CRC metastasis and proliferation.     

The role of microRNAs involved in PI3-kinase signaling pathway in colorectal cancer

In recent decades, cancer has been one of the most important concerns of the human community, which affects human life from many different ways, such as breast, lung, colorectal, prostate, and other cancers. Colorectal cancer is one of the most commonly diagnosed cancers in the world that has recently been introduced as the third leading cause of cancer deaths in the world. microRNAs have a very crucial role in tumorgenesis and prevention of cancer, which plays a significant role with influencing various factors through different signaling pathways. Phosphoinositide 3 (PI3)-kinase/AKT is one of the most important signaling pathways involved in the control and growth of tumor in colorectal cancer, through important proteins of this pathway, such as PTEN and AKT, that they can perform specific influence on this process. Our effort in this study is to collect microRNAs that act as tumor suppressors and oncomirs in this cancer through PI3-kinase/AKT signaling pathway.     

Use of stem cells as carriers of oncolytic viruses for cancer treatment

Therapeutic application of stem cells and oncolytic viruses in cancer treatment has rapidly increased in the last decade. Oncolytic viruses are considered as a new class of anticancer agents because of their ability to selectively infect and destroy cancer cells. Furthermore, regarding the specific migratory capacity of stem cells, they can be used as carriers or vectors targeting metastatic cancer. Promising results have been reported regarding the use of stem cells and oncolytic viruses as a therapeutic approach for the treatment of metastatic cancer. The present review aimed to determine the approaches involved in the use of the tumor-homing capacity of stem cells for cancer treatment.     

The effects of methyl jasmonate and salicylic acid on the production of secondary metabolites in organ culture of Ziziphora persica

Plant Cell, Tissue and Organ Culture (PCTOC) - Ziziphora persica (Lamiaceae) has been used as infusions and decoctions in traditional medicine for various purposes such as sedative, carminative,...     

Phenylketonuria in Iranian population: a study in institutions for mentally retarded in Isfahan

Phenylalanine hydroxylase (PAH) deficiency is caused by mutations in the PAH gene (12q22-q24) resulting in a primary deficiency of the PAH enzyme activity, intolerance to the dietary intake of phenylalanine (Phe) and production of the phenylketonuria (PKU) disease. To date there have been no reports on the molecular analysis of PKU in Iranian population. In this study, the states of the PKU disease in terms of prevalence and mutation spectrum among patients reside in the institutions for mentally retarded in Isfahan was investigated. In the first step, 611 out of 1541 patients with PKU phenotype or severe mental retardation were screened for the PKU disease using the Guthrie bacterial inhibition assay (GBIA) followed by HPLC. Among the patients screened 34 (5.56%) were found positive with abnormal serum Phe of above 7mg/dl. In the next step, the presence of 18 common mutations of the PAH gene in 26 of the patients with classical PKU (serum Phe above 20mg/dl) was investigated, using the polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). Of the 52 independent mutant alleles that were analyzed, 34 (65.38%) were genotyped showing 8 mutations as follows: R252W (15.38%), Q232Q (13.46%), R261Q (7.69%), delL364 (7.69%), IVS10-11g>a (5.77%), L333F (5.77%), V245V (5.77%) and S67P (3.85%). The results from this study may serve as a reference to analyze the PKU mutations in other part of Iran, and to establish diagnostic tests for carrier detection and prenatal diagnosis of the PKU disease in Iranian population.     

Improving Multi-Epitope Long Peptide Vaccine Potency by Using a Strategy that Enhances CD4+ T Help in BALB/c Mice

Peptide-based vaccines are attractive approaches for cancer immunotherapy; but the success of these vaccines in clinical trials have been limited. Our goal is to improve immune responses and anti-tumor effects against a synthetic, multi-epitope, long peptide from rat Her2/neu (rHer2/neu) using the help of CD4+ T cells and appropriate adjuvant in a mouse tumor model. Female BALB/c mice were vaccinated with P₅₊₄₃₅ multi-epitope long peptide that presents epitopes for cytotoxic T lymphocytes (CTL) in combination with a universal Pan DR epitope (PADRE) or CpG-oligodeoxynucleotides (CpG-ODNs) as a Toll-like receptor agonist adjuvant. The results show that vaccination with the multi-epitope long peptide in combination with the PADRE peptide and CpG-ODN induced expansion of subpopulations of CD4+ and CD8+ cells producing IFN-γ, the average tumor size in the vaccinated mice was less than that of the other groups, and tumor growth was inhibited in 40% of the mice in the vaccinated group. The mean survival time was 82.6 ± 1.25 days in mice vaccinated with P₅₊₄₃₅ + CpG+ PADRE. Our results demonstrate that inclusion of PADRE and CpG with the peptide vaccine enhanced significant tumor specific-immune responses in vaccinated mice.