Hsp Inhibitor is Affective Against Adenocarcinomic Human Alveolar Basal Epithelial Cells Through Modulating ERK/MAPK Signaling Pathway.

The extracellular signal-regulated kinase (ERK) - mitogen-activated protein kinase (MAPK) pathway regulates cell proliferation, differentiation, and apoptosis. Heat Shock Protein 90 (HSP90) is required to activate proto-oncogenic protein kinases and promotes tumor growth through anti-apoptotic effects on A549-non-small cell lung cancer (NSCLC). Therefore, deregulation of the ERK-MAPK pathway and abnormal expression of HSP90 are reasonably frequent events in NSCLC. In this study, novel perimidine-pyrazole compounds employed to block ERK-MAPK deregulation through inhibiting HSP dependent cancer cell survival mechanisms. A set of perimidine-pyrazole derivatives effects was monitored on NSCLC cell line. Array experiments performed to understand the effect of the compounds on signaling pathways and results were analyzed by gene enrichment analysis. Further, senescence and apoptosis experiments were performed to support the enrichment results along with in silico methods to determine perimidine-pyrazole/HSP interactions. Treatment of NSCLC cells with perimidine-pyrazole derivatives displayed cancer-inhibitory, pro-senescent and pro-apoptotic effects on NSCLC cells through ERK/MAPK pathway and these compounds are promising templates for designing anticancer drugs.

Triad pyrazole-thiazole-coumarin heterocyclic core effectively inhibit HSP and drive cancer cells to apoptosis.

Intensive studies on hepatocellular carcinoma (HCC), which is spreading rapidly around the world and has a high mortality rate, is due to the lack of adequate preventive or curative treatment methods. Treating patients with HCC has become very challenging because of the heterogeneity in the patient population lead activation of different signaling pathways, and pathway crosstalk for patients. Therefore, understanding these molecular mechanisms and combining drugs with molecular therapies to overcome these drawbacks has become an area of utmost importance. In this study, the biological activities of the designed and characterized triad Pyrazole-Thiazol-Coumarin (PTC) compounds were determined by performing cell viability, qPCR array, apoptosis and cell cycle assays. One of the compounds (PTC10) implicitly suppresses multiple pathways (RAS/MAP kinase and PI3K-AKT) simultaneously. This action is provided by (i) arresting cancer cells at G2 phase, (ii) driving cancer cells to apoptosis and (iii) inhibiting HSP network. Remarkably, HSP is an apoptotic factor and help cancer cell to survive. HSP90 also coordinates with Cdk4/Cdc37, therefore inhibiting HSP both drives cells to arrest and apoptosis. ATP hydrolysis and aggregation assay further displayed specific HSP inhibition. Therefore, PTC provides a unique drug template for HCC treatment.

MicroRNAs and Heat Shock Proteins in Breast Cancer Biology.

Breast cancer has five major immune types; luminal A, luminal B, HER2, Basal-like, and normal-like. Cells produce a family of protein called heat shock proteins (Hsps) in response to exposure to thermal and other proteotoxic stresses play essential roles in cancer metabolism and this large family shows a diverse set of Hsp involvement in different breast cancer immune types. Recently, Hsp members categorized according to their immune type roles. Hsp family consists of several subtypes formed by molecular weight; Hsp70, Hsp90, Hsp100, Hsp40, Hsp60, and small molecule Hsps. Cancer cells employ Hsps as survival factors since most of these proteins prevent apoptosis. Several studies monitored Hsp roles in breast cancer cells and reported Hsp27 involvement in drug resistance, Hsp70 in tumor cell transformation-progression, and interaction with p53. Furthermore, the association of Hsp90 with steroid receptors and signaling proteins in patients with breast cancer directed research to focus on Hsp-based treatments. miRNAs are known to play key roles in all types of cancer that are upregulated or downregulated in cancer which respectively referred to as oncogenes (oncomirs) or tumor suppressors. Expression profiles of miRNAs may be used to classify, diagnose, and predict different cancer types. It is clear that miRNAs play regulatory roles in gene expression and this work reveals miRNA correlation to Hsp depending on specific breast cancer immune types. Deregulation of specific Hsp genes in breast cancer subtypes allows for identification of new targets for drug design and cancer treatment. Here, we performed miRNA network analysis by recruiting Hsp genes detected in breast cancer subtypes and reviewed some of the miRNAs related to aforementioned Hsp genes.

Involvement of miRNAs and Pseudogenes in Cancer.

Our understanding of cancer pathways has been changed by the determination of noncoding transcripts in the human genome in recent years. miRNAs and pseudogenes are key players of the noncoding transcripts from the genome, and alteration of their expression levels provides clues for significant biomarkers in pathogenesis of diseases. Especially, miRNAs and pseudogenes have both oncogenic and tumor-suppressive roles in each step of cancer tumorigenesis. In this current study, association between oncogenes and miRNAs-pseudogenes was reviewed and determined in human cancer by the CellMiner web-tool.

Tumor Targeting of Polymeric Nanoparticles Conjugated with Peptides, Saccharides, and Small Molecules for Anticancer Drugs.

Targeting drugs or pharmaceutical compounds to tumor site increases cancer treatment efficiency and therapeutic outcome. Nanoparticles are unique delivery systems for site-targeting within an organism. Many novel technologies have been established in drug research and development area. Nanotechnology now offers nanometer size polymeric nanoparticles and these particles direct drugs to their targets, protect drugs against degradation, and release the drug in a controlled manner. Modification of nanoparticle surface by molecules leads to prolonged retention and accumulation in the target area of the organism. Current efforts of designing polymeric nanoparticles include drug activation in the target area, controlled drug release at the site upon stimulation, and increased drug loading capacity of drug polymer conjugates. Recent progress in molecular mechanism elucidation of cancer cell and rising research in nanoparticle designs may provide efficient cancer treatment modality and innovative nanoparticle designs in the near future. Recent years have seen many developments in the field of innovative peptide based drug nanoparticles. Although none of them approved to be used in clinics yet, peptides are promising structures due to their simple and nonantigenic nature. Biodegradable materials are also preferred materials in drug delivery. Polysaccharide-based micelle systems improve hydrophobic drug and protein delivery. Ease of saccharide structure modification improves pharmacokinetic and pharmacodynamic properties of drug molecules as well as their delivery to a specific site in a controlled manner and sustained rate. Small molecules, especially drugs, conjugated to nanoparticles and several nanoparticles of this type are in the clinical trials and at the market. This review provides recent developments of polymeric nanoparticles conjugated with peptides, saccharides, and small molecules in cancer theraphy.

Design, Synthesis, and Evaluation of Heat Shock Protein 90 Inhibitors in Human Breast Cancer and Its Metastasis.

BACKGROUND: Despite development of novel cancer drugs, invasive ductal breast carcinoma and its metastasis are still highly morbid. Therefore, new therapeutic approaches are being developed and Hsp90 is an important target for drug design. For this purpose, a series of benzodiazepine derivatives were designed and synthesized as novel Hsp90 inhibitor. METHODS: Benzodiazepine derivatives anticancer activities were determined by XTT cell proliferation assay against human breast cancer cell line (MCF-7). Effects of the compounds on endothelial function were monitored on human vascular endothelium (HUVEC) cell line as well. In order to determine the anti-proliferative mechanism of the compounds, in silico molecular docking studies were performed between Hsp90 ATPase domain and the benzodiazepine derivatives. Further, these compounds perturbation on Hsp90 ATPase function were tested. Fluorescence binding experiments showed that the derivatives bind Hsp90 effectively. Expression analysis of known cancer drug target genes by PCR array experiments suggest that the benzodiazepine derivatives have remarkable anticancer activity. RESULTS: A representative Benzodiazepine derivative D5 binds Hsp90 with Kd value of 3,93 µM and with estimated free energy of binding -7.99 (kcal/mol). The compound decreases Hsp90 ATPase function and inhibit Hsp90 client protein folding activity. The compound inhibits expression of both Hsp90 isoforms and key proteins (cell cycle receptors; PLK2 and TERT, kinases; PI3KC3 and PRKCE, and growth factors; IGF1, IGF2, KDR, and PDGFRA) on oncogenic pathways. CONCLUSION: Benzodiazepine derivatives presented here display anticancer activity. The compounds effect on both breast cancer and endothelial cell lines show their potential as drug templates to inhibit breast cancer and its metastasis.

Regulation of oncogenic genes by MicroRNAs and pseudogenes in human lung cancer.

Lung cancer is one of the most common mortal cancer types both for men and women. Several different biomarkers have been analyzed to reveal lung cancer prognosis pathways for developing efficient therapeutics and diagnostic agents. microRNAs (miRNAs) and pseudogenes are critical biomarkers in lung cancer and alteration of their expression levels has been identified in each step of lung cancer tumorigenesis. miRNAs and pseudogenes are crucial gene regulators in normal cells as well as in lung cancer cells, and they have both oncogenic and tumor-suppressive roles in lung cancer tumorigenesis. In this study, we have determined the relationship between lung cancer related oncogenes and miRNAs along with pseudogenes in lung cancer, and the results indicate their potential as biological markers for diagnostic and therapeutic purposes.

Therapeutic Targeting of microRNAs in Cancer: Future Perspectives.

Preclinical Research The discovery of microRNAs (miRNAs) and their link with cancer has opened a new era in cancer therapeutics. Approximately, 18 - 24 nucleotides long, miRNAs can up-regulate or down-regulate gene expression in many cancer types and are respectively categorized as oncogenes (oncomirs) or tumor suppressors. Expression profiles of miRNAs with biomarker potential can be used for the classification, diagnosis, therapeutic treatment, and prognosis of different cancer types. miRNA mimics and miRNA antagonists are the two main approaches to miRNA-based cancer therapies that respectively inhibit oncomirs or restore the expression of tumor suppressive miRNAs. This review serves to provide some general insight into miRNA biogenesis, cancer related miRNAs, and miRNA therapeutics.

Regulation of Heat Shock Proteins by miRNAs in human breast cancer.

Metabolic rates of cancer cells are faster compared to normal cells. This faster rate yields aberrant protein folding and causes loss of protein function. Therefore, cancer cells need more Heat Shock Proteins (HSPs) for proper substrate- protein folding on oncogenic pathways. Pseudogenes regulate tumor suppressors and oncogenes, and pseudogenes are deregulated in cancer progression. Further, alterations in miRNA expression have been identified in different cancer types. MiRNAs also have both oncogenic and tumour-suppressive roles in breast cancer post-transcriptional gene regulation. Breast cancer is a genetic disease and we performed miRNA analysis in human breast cancer cell lines to identify miRNAs in association with HSPs and pseudogenes by employing CellMiner; a web-based suite. CellMiner integrates several databases and help analysing microarray metadata. The experimental data provide a platform for researchers to compare macromolecules' relationships in NCI-60 cell lines. Breast cancer associated miRNAs gathered from literature and analyzed by employing this suite, significantly correlated HSP genes and pseudogenes in the breast cancer are determined as; HSPA13, HSP90AB1, TRAP1, HSPB1, DNAJB4, HSPD1 and HSP90AA4P, HSPB1P1, DNAJC8P1, HSPD1P9 respectively. HSPs involved in breast cancer are regulated by several miRNAs and miRNA regulators from CellMiner data found as hsa-miR-17, hsa-miR-22, hsa-miR-93, hsa-miR-106a, hsa-miR-125b, hsa-miR-130a, and hsamiR- 141. Cross check of the determined miRNAs and target HSPs was performed by target site prediction software. Comparison of the experimental data from CellMiner and software predicted data indicate differences. CellMiner data provide a vast miRNA types compared to prediction softwares-web tools data and reported miRNAs in the literature. Therefore, reported key miRNAs in this work that are not studied earlier may help cancer researchers to uncover novel posttranslational regulation mechanisms. Cancer cells use HSP network as an escape mechanism from apoptosis, therefore inhibition of associated HSPs by modulating miRNAs may provide a novel therapy for the tumorigenesis.

MicroRNAs and cancer; an overview.

MiRNAs are a family of small, endogenous, and evolutionarily conserved non-coding ribonucleic acids that have been involved in the regulation of several essential, cellular, and functional processes. MicroRNAs are known to play key roles in all types of cancer and function as oncogenes (oncomirs) or tumour-suppressors in up-regulation or down-regulation processes respectively. MiRNAs have potential power to be examined as prognostic and diagnostic biomarkers. Modulating miRNAs, based on two major approaches (miRNA mimics and miRNA antagonists), is used for clinical development of therapeutic miRNAs. This review emphasizes the latest discovery in the field of miRNA research involved in cancer, biomarkers, and therapeutics.

Isolation and identification of free-living amoebae from tap water in Sivas, Turkey.

The present work focuses on a local survey of free-living amoebae (FLA) that cause opportunistic and nonopportunistic infections in humans. Determining the prevalence of FLA in water sources can shine a light on the need to prevent FLA related illnesses. A total of 150 samples of tap water were collected from six districts of Sivas province. The samples were filtered and seeded on nonnutrient agar containing Escherichia coli spread. Thirty-three (22%) out of 150 samples were found to be positive for FLA. The FLA were identified by morphology and by PCR using 18S rDNA gene. The morphological analysis and partial sequencing of the 18S rDNA gene revealed the presence of three different species, Acanthamoeba castellanii, Acanthamoeba polyphaga, and Hartmannella vermiformis. Naegleria fowleri, Balamuthia mandrillaris, or Sappinia sp. was not isolated during the study. All A. castellanii and A. polyphaga sequence types were found to be genotype T4 that contains most of the pathogenic Acanthamoeba strains. The results indicated the occurrence and distribution of FLA species in tap water in these localities of Sivas, Turkey. Furthermore, the presence of temperature tolerant Acanthamoeba genotype T4 in tap water in the region must be taken into account for health risks.

Heat, pH induced aggregation and surface hydrophobicity of S. cerevesiae Ssa1 protein.

Heat shock protein 70 is a conserved protein among organisms. Hsp70 helps substrate proteins to fold correctly. Unfolded substrate proteins increase the probability of the aggregate formation. High level recombinant protein expression in biotechnology often leads insoluble inclusion bodies. To prevent aggregation and to obtain high levels of soluble proteins, Hsp co-expression with desired recombinant protein in yeast becomes a popular method. For this purpose, S. cerevesiae cytosolic Hsp70 (Ssa1) biochemical properties were characterized. Alteration of Ssa1 structure between ATP- and ADP-bound states regulates its function. Therefore, conformation-dependent Ssa1 hydrophobicity and as a result aggregation may also play a key role in Ssa1 function. Therefore, a combination of FTIR, acrylamide quenching, and ANS was used to investigate the effect of nucleotide binding on the structure of Ssa1. Ssa1 secondary structure alterations and hydrophobic properties in aqueous solutions with differing ionic strengths and temperature were also studied.

Heat shock proteins; an overview.

Heat shock proteins (Hsps) protect protein substrates against conformational damage to promote the function of the proteins, prevent aggregation and prevent formation of toxic inclusion bodies. Protein aggregates and fibrils have been associated with neurodegenerative diseases and with inclusion bodies. High-level expression of recombinant protein for biotechnological purposes often leads to insoluble inclusion bodies. Therefore, misfolded proteins must be properly folded or must be degraded through heat shock protein action. This function protects cells against cytotoxic outcomes. In addition to their cytoprotective roles, Hsps are involved in other functions since Hsps exist in all types of cells and tissues. Therefore, several diseases are associated with alterations of these biochemical functions. This first review of the theme issue will discuss general properties of Hsps concisely along with their potential use in pharmaceutical and biotechnological applications.

Ydj1 but not Sis1 stabilizes Hsp70 protein under prolonged stress in vitro.

Yeast cytosol has two important co-chaperons; Ydj1 and Sis1. Genetic experiments showed that Ydj1 is not essential for viability; however, cells lacking it grow very poorly at 30 degrees C or unable to grow at extreme temperatures. On the other hand, Sis1 is an essential protein and apparently plays a functional role at assembly or disassembly of protein complexes. Stability experiments revealed that only Ydj1-protected Hsp70 proteins can hydrolyze ATP under prolonged stress.