Evaluation of the changes in the expression levels of miR-141 and SHP gene in prostate cancer specimens

Introduction: Primary screening tests currently used for prostate cancer (PCa), don’t have sufficient sensitivity and specificity. Therefore, early diagnosis and management of treatment is one of the challenges faced by physicians. Today, more familiar with the signaling pathways involved in the pathogenesis of cancers, several molecules have been introduced as diagnostic biomarker or drug design. The androgen receptor is one of the most important pathways involved in the pathogenesis of PCa. The miR-141, as a member of the miR-200 family has a regulatory role by targeting the Small heterodimer partner (SHP , NR0B2) at the downstream of this molecular pathway. Objective: The aim of this study was to investigate changes in the expression of miR-141 and SHP in tissue samples of PCa patients compared to benign prosttic hyperplasia (BPH) tissues. Method: In this study, changes in expression of miR-141 and SHP at the RNA level were performed using qRT-PCR technique on 68 prostate tissues containing, 26 localized PCa, 4 metastatic PCa, 30 BPH and 8 tumor-adjacent normal tissues. Also, the analysis of the results was investigated using REST software. Changes in SHP expression at protein level were investigated in 20 Paraffin-embedded tissue blocks containing 10 PCa and 10 BPH using immunohistochemistry (IHC). Results: The findings of this study showed that miR-141 increased in metastatic samples compared with localized samples (P <0.001, 31.17-fold change). Tumor samples showed a lower expression level of SHP compared with BPH tissues at mRNA and protein level (p = 0.014, 4.7 fold change) and (p = 0.02, 1.8 fold change), respectively. Conclusion: According to our results, it can be concluded that miR-141 plays a role in the pathogenesis of PCa through the androgen receptor signaling pathway and the SHP regulation. Also, miR-141 has a high potential for diagnosis of PCa as a prognostic biomarker. Keywords: Prostate cancer, SHP gene, miR-141, Biomarke

Review of molecular mechanisms underlying gemcitabine resistance in pancreatic cancer

Pancreatic cancer is one the most malignant cancers in human. A great percentage of patients die annually due to lack of early detection as well as efficient treatment strategies. Only five-year survival rate is still only seen in 5% of patients. Major problem of this deadly disease is the intrinsic and acquired resistance to current chemotherapeutic agents such as gemcitabine. So far, different molecular mechanisms are attributed to gemcitabine resistance. For instance, genetic mechanisms, aberrant gene expression in cellular signaling pathways, cancer stem cells, impaired apoptosis related genes, epigenetic changes and potential role of microRNAs have been identified in gemcitabine resistance of pancreatic cancer. Improving the drug efficacy and overcoming to drug resistance is the current goal in treatment of pancreatic cancer. Understanding the cellular and molecular mechanisms of resistance can help us to develop novel therapeutic approaches leading to increased effectiveness of current treatments. In this review, we summarized the molecular mechanisms involved in gemcitabine resistance in pancreatic cancer

Review of molecular mechanisms underlying gemcitabine resistance in pancreatic cancer

Pancreatic cancer is one the most malignant cancers in human. A great percentage of patients die annually due to lack of early detection as well as efficient treatment strategies. Only five-year survival rate is still only seen in 5% of patients. Major problem of this deadly disease is the intrinsic and acquired resistance to current chemotherapeutic agents such as gemcitabine. So far, different molecular mechanisms are attributed to gemcitabine resistance. For instance, genetic mechanisms, aberrant gene expression in cellular signaling pathways, cancer stem cells, impaired apoptosis related genes, epigenetic changes and potential role of microRNAs have been identified in gemcitabine resistance of pancreatic cancer. Improving the drug efficacy and overcoming to drug resistance is the current goal in treatment of pancreatic cancer. Understanding the cellular and molecular mechanisms of resistance can help us to develop novel therapeutic approaches leading to increased effectiveness of current treatments. In this review, we summarized the molecular mechanisms involved in gemcitabine resistance in pancreatic cancer

Molecular alterations contributing to pancreatic cancer chemoresistance

Pancreatic ductal adenocarcinoma (PDAC) is one of the most common causes of cancer-related death all over the world. This disease is difficult to treat and patients have an overall 5-year survival rate of less than 5%. Although two drugs, gemcitabine (GEM) and 5-fluorouracil (5-FU) have been shown to improve the survival rate of patients systematically, they do not increase general survival to a clinically acceptable degree. Lack of ideal clinical response of pancreatic cancer patients to chemotherapy is likely to be due to intrinsic and acquired chemoresistance of tumor cells. Various mechanisms of drug resistance have been investigated in pancreatic cancer, including genetic and epigenetic changes in particular genes or signaling pathways. In addition, evidence suggests that microRNAs (miRNAs) play significant roles as key regulators of gene expression in many cellular processes, including drug resistance. Understanding underlying genes and mechanisms of drug resistance in pancreatic cancer is critical to develop new effective treatments for this deadly disease. This review illustrates the genes and miRNAs involved in resistance to gemcitabine in pancreatic cance

The Effect of EFG1 Gene Silencing on Down-Regulation of SAP5 Gene, by Use of RNAi Technology

Efg1 transcription factor is believed to be the main regulator of hyphal formation under many different conditions. In addition, it is responsible for positive regulation of the expression of several hyphal-specific genes. SAP5, which encodes secreted aspartic proteinase, is one of the mentioned genes and is crucial for pathogenicity properties. In the present work we have established the experimental conditions for the use of siRNA in the diploid yeast Candida albicans in order to knock-down the EFG1 gene expression as well as the Efg1-dependent gene, SAP5. The 19-nucleotide siRNA was designed according to cDNA sequence of EFG1 gene in C. albicans and modified-PEG/LiAc method was applied for yeast transfection. To quantify the level of both EFG1 and SAP5 gene expression, the cognate mRNAs were measured in C. albicans by quantitative real-time RT-PCR and data was consequently analyzed by use of REST® software. Images taken by fluorescent microscopy method indicated the effectiveness of transfection. According to REST® software data analysis, expression of EFG1 gene decreased about 2.5-fold using 500 nM of siRNA. A 7-fold decrease in EFG1 gene expression was observed when applying 1 µM of siRNA (P<0.05). Consequently, the expression of SAP5 was significantly down-regulated both in yeast treated with 500 and 1000 nM of siRNA (P<0.05). In conclusion, post-transcriptional gene silencing (PTGS) is likely to be considered as a promising approach to discover new gene targets so as to design fungal-specific antifungal agents, and it is strongly possible that we are taking the right way to battle with C. albicans-associated infections

The chicken chorioallantoic membrane model for isolation of CRISPR/cas9-based HSV-1 mutant expressing tumor suppressor p53.

Oncolytic viruses (OVs) have emerged as a novel cancer treatment modality, which selectively target and kill cancer cells while sparing normal ones. Among them, engineered Herpes simplex virus type 1 (HSV-1) has been proposed as a potential treatment for cancer and was moved to phase III clinical trials. Previous studies showed that design of OV therapy combined with p53 gene therapy increases the anti-cancer activities of OVs. Here, the UL39 gene of the ICP34.5 deleted HSV-1 was manipulated with the insertion of the EGFP-p53 expression cassette utilizing CRISPR/ Cas9 editing approach to enhance oncoselectivity and oncotoxicity capabilities. The ΔUL39/Δγ34.5/HSV1-p53 mutant was isolated using the chorioallantoic membrane (CAM) of fertilized chicken eggs as a complementing membrane to support the growth of the viruses with gene deficiencies. Comparing phenotypic features of ΔUL39/Δγ34.5/HSV1-p53-infected cells with the parent Δγ34.5/HSV-1 in vitro revealed that HSV-1-P53 had cytolytic ability in various cell lines from different origin with different p53 expression rates. Altogether, data presented here illustrate the feasibility of exploiting CAM model as a promising strategy for isolating recombinant viruses such as CRISPR/Cas9 mediated HSV-1-P53 mutant with less virus replication in cell lines due to increased cell mortality induced by exogenous p53

MiR‑608 regulating the expression of ribonucleotide reductase M1 and cytidine deaminase is repressed through induced gemcitabine chemoresistance in pancreatic cancer cells

Purpose Gemcitabine resistance is the main problem in pancreatic adenocarcinoma patients. Hence, we aimed to identify the correlation between expression of RRM1 and CDA as the resistance genes and their predicted targeting miR-608 in the resistant pancreatic cancer cell lines to gemcitabine. Methods Dual luciferase assay was performed to determine whether both RRM1 and CDA are targeted by miR-608 in 293T and pancreatic cancer cell lines. AsPC-1 and MIA PaCa-2 cell lines became gradually resistant to gemcitabine by exposing to the increasing doses of gemcitabine. After RNA and miRNAs extraction and cDNA conversion, the expressions of RRM1, CDA and miR-608 in all cell lines were studied by quantitative PCR. Pre-miR-608 transfection to the cell lines was done by calcium phosphate method. MTT assay was performed for analyzing the chemo sensitivity of different cell lines to gemcitabine. Results Luciferase assays showed that miR-608 targeted RRM1 and CDA genes in 293T, AsPC-1 and MIA PaCa-2 cell lines. Compared to parental cell line, resistant MIA PaCa-2 and AsPC-1 cells demonstrated increased expression of RRM1 and CDA. On the other hand the expression of miR-608 in resistant MIA PaCa-2 and AsPC-1 cells was lower than parental cells. Furthermore, transfection of MIA PaCa-2 and AsPC-1 cells by miR-608 lead to decreased expression of RRM1 and CDA and lowered viability of the cells in comparison with scrambled microRNA transfected cells. Conclusion During resistance induction in pancreatic cancer cells, miR-608 which is targeting RRM1 and CDA is downregulated which leads to upregulation of these genes. Keywords Pancreatic neoplasms · Gemcitabine resistance · RRM1 protein, human · CDA · MIRNA-608, microRNA, huma

Rational design of DKK3 structure-based small peptides as antagonists of Wnt signaling pathway and in silico evaluation of their efficiency.

Dysregulated Wnt signaling pathway is highly associated with the pathogenesis of several human cancers. Dickkopf proteins (DKKs) are thought to inhibit Wnt signaling pathway through binding to lipoprotein receptor-related protein (LRP) 5/6. In this study, based on the 3-dimensional (3D) structure of DKK3 Cys-rich domain 2 (CRD2), we have designed and developed several peptide inhibitors of Wnt signaling pathway. Modeller 9.15 package was used to predict 3D structure of CRD2 based on the Homology modeling (HM) protocol. After refinement and minimization with GalaxyRefine and NOMAD-REF servers, the quality of selected models was evaluated utilizing VADAR, SAVES and ProSA servers. Molecular docking studies as well as literature-based information revealed two distinct boxes located at CRD2 which are actively involved in the DKK3-LRP5/6 interaction. A peptide library was constructed conducting the backrub sequence tolerance scanning protocol in Rosetta3.5 according to the DKK3-LRP5/6 binding sites. Seven tolerated peptides were chosen and their binding affinity and stability were improved by some logical amino acid substitutions. Molecular dynamics (MD) simulations of peptide-LRP5/6 complexes were carried out using GROMACS package. After evaluation of binding free energies, stability, electrostatic potential and some physicochemical properties utilizing computational approaches, three peptides (PEP-I1, PEP-I3 and PEP-II2) demonstrated desirable features. However, all seven improved peptides could sufficiently block the Wnt-binding site of LRP6 in silico. In conclusion, we have designed and improved several small peptides based on the LRP6-binding site of CRD2 of DKK3. These peptides are highly capable of binding to LRP6 in silico, and may prevent the formation of active Wnt-LRP6-Fz complex

Meta-analysis of promoter methylation in eight tumor-suppressor genes and its association with the risk of thyroid cancer.

Promoter methylation in a number of tumor-suppressor genes (TSGs) can play crucial roles in the development of thyroid carcinogenesis. The focus of the current meta-analysis was to determine the impact of promoter methylation of eight selected candidate TSGs on thyroid cancer and to identify the most important molecules in this carcinogenesis pathway. A comprehensive search was performed using Pub Med, Scopus, and ISI Web of Knowledge databases, and eligible studies were included. The methodological quality of the included studies was evaluated according to the Newcastle Ottawa scale table and pooled odds ratios (ORs); 95% confidence intervals (CIs) were used to estimate the strength of the associations with Stata 12.0 software. Egger's and Begg's tests were applied to detect publication bias, in addition to the "Metatrim" method. A total of 55 articles were selected, and 135 genes with altered promoter methylation were found. Finally, we included eight TSGs that were found in more than four studies (RASSF1, TSHR, PTEN, SLC5A, DAPK, P16, RARβ2, and CDH1). The order of the pooled ORs for these eight TSGs from more to less significant was CDH1 (OR = 6.73), SLC5 (OR = 6.15), RASSF1 (OR = 4.16), PTEN (OR = 3.61), DAPK (OR = 3.51), P16 (OR = 3.31), TSHR (OR = 2.93), and RARβ2 (OR = 1.50). Analyses of publication bias and sensitivity confirmed that there was very little bias. Thus, our findings showed that CDH1 and SCL5A8 genes were associated with the risk of thyroid tumor genesis

Multi-targeting of K-Ras domains and mutations by peptide and small molecule inhibitors.

K-Ras activating mutations are significantly associated with tumor progression and aggressive metastatic behavior in various human cancers including pancreatic cancer. So far, despite a large number of concerted efforts, targeting of mutant-type K-Ras has not been successful. In this regard, we aimed to target this oncogene by a combinational approach consisting of small peptide and small molecule inhibitors. Based on a comprehensive analysis of structural and physicochemical properties of predominantly K-Ras mutants, an anti-cancer peptide library and a small molecule library were screened to simultaneously target oncogenic mutations and functional domains of mutant-type K-Ras located in the P-loop, switch I, and switch II regions. The selected peptide and small molecule showed notable binding affinities to their corresponding binding sites, and hindered the growth of tumor cells carrying K-RasG12D and K-RasG12C mutations. Of note, the expression of K-Ras downstream genes (i.e., CTNNB1, CCND1) was diminished in the treated Kras-positive cells. In conclusion, our combinational platform signifies a new potential for blockade of oncogenic K-Ras and thereby prevention of tumor progression and metastasis. However, further validations are still required regarding the in vitro and in vivo efficacy and safety of this approach