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Despite of the capacity that several drugs have for specific inhibition of the androgen receptor (AR), in most cases, PCa progresses to an androgen-independent stage. In this context, the development of new targeted therapies for prostate cancer (PCa) has remained as a challenge. To overcome this issue, new tools, based on nucleic acids technology, have been developed. Aptamers are small oligonucleotides with a three-dimensional structure capable of interacting with practically any desired target, even large targets such as mammalian cells or viruses. Recently, aptamers have been studied for treatment and detection of many diseases including cancer. In PCa, numerous works have reported their use in the development of new approaches in diagnostics and treatment strategies. Aptamers have been joined with drugs or other specific molecules such as silencing RNAs (aptamer–siRNA chimeras) to specifically reduce the expression of oncogenes in PCa cells. Even though these studies have shown good results in the early stages, more research is still needed to demonstrate the clinical value of aptamers in PCa. The aim of this review was to compile the existing scientific literature regarding the use of aptamers in PCa in both diagnosis and treatment studies. Since Prostate-Specific Membrane Antigen (PSMA) aptamers are the most studied type of aptamers in this field, special emphasis was given to these aptamers.

The Dp71 protein is the most abundant dystrophin in the central nervous system (CNS). Several dystrophin Dp71 isoforms have been described and are classified into three groups, each with a different C-terminal end. However, the functions of Dp71 isoforms remain unknown. In the present study, we analysed the effect of Dp71eΔ71 overexpression on neuronal differentiation of PC12 Tet-On cells. Overexpression of dystrophin Dp71eΔ71 stimulates neuronal differentiation, increasing the percentage of cells with neurites and neurite length. According to 2-DE analysis, Dp71eΔ71 overexpression modified the protein expression profile of rat pheochromocytoma PC12 Tet-On cells that had been treated with neuronal growth factor (NGF) for nine days. Interestingly, all differentially expressed proteins were up-regulated compared to the control. The proteomic analysis showed that Dp71eΔ71 increases the expression of proteins with important roles in the differentiation process, such as HspB1, S100A6, and K8 proteins involved in the cytoskeletal structure and HCNP protein involved in neurotransmitter synthesis. The expression of neuronal marker TH was also up-regulated. Mass spectrometry data are available via ProteomeXchange with identifier PXD009114. SIGNIFICANCE: This study is the first to explore the role of the specific isoform Dp71eΔ71. The results obtained here support the hypothesis that the dystrophin Dp71eΔ71 isoform has an important role in the neurite outgrowth by regulating the levels of proteins involved in the cytoskeletal structure, such as HspB1, S100A6, and K8, and in neurotransmitter synthesis, such as HCNP and TH, biological processes required to stimulate neuronal differentiation.

Amphiphysin 2 and members of the BAR-domain family of proteins participate in a wide array of cellular processes including cell cycle and endocytosis. Given that amphiphysin 2 is related to diverse cell responses as a result of metabolic stress, we investigated in macrophages whether oxidative stress originated by the internalization of oxidized low density lipoproteins (oxLDL) affect both, the expression of amphiphysin 2 and its binding partner c-Myc. Here we report that under oxidative stress, a complex formation between amphiphysin 2(Bin1) and c-Myc allows the cell to develop a novel survival equilibrium state established between cell proliferation and cell death. We propose that under conditions of oxidative stress given by the internalization of oxLDL, macrophages employ the formation of the amphiphysin 2(Bin1)/c-Myc complex as a control mechanism to initially avoid the process of cell death in an attempt to prolong cell survival.

Legumes are unique in their ability to establish symbiotic interactions with rhizobacteria, providing a source of assimilable nitrogen; this symbiosis is regulated by complex signaling process between the plant and the bacteria. The participation of specific protein kinases during the initial steps of the nodulation process has been established. However, their substrates or the signaling networks implicated are not fully understood. Herein, a phosphoproteomic analysis of Phaseolus vulgaris roots treated for 24 h with specific Nod factors was performed using an immobilized metal ion affinity chromatography enrichment and two-dimensional gel electrophoresis approach with mass spectrometry identification. A total of 33 protein spots showing more than 1.5-fold shift were identified (17 protein spots in which the relative abundance increased and 16 that decreased). The majority of the identified root phosphoproteins displaying an increased relative abundance are presumed to have functions related to the biosynthesis and folding of proteins, energy metabolism, or cytoskeleton rearrangements, which reflect the metabolic status of the roots as being part of the developmental processes leading to nodule initiation and the importance of cytoskeleton rearrangement in the P. vulgaris–rhizobia symbiosis. The proteins in which relative abundance decreased are associated with defense and oxido-reduction processes, which could indicate a suppression of plant defense responses during the establishment of the rhizobia–legume interaction and an increase of reactive oxygen species production.

The Hospital Infantil de México Federico Gómez (HIMFG) is a tertiary care hospital in Mexico City where Escherichia coli is frequently isolated from the urine samples of pediatric patients with urinary tract infections. A collection of 178 urinary Escherichia coli (UEc) isolates associated with complicated and uncomplicated urinary tract infections were evaluated in this study. The patterns of resistance to 9 antibiotic classes showed that 60.7% of the UEc isolates had a highly multidrug-resistant (MDR) profile. Genetic diversity analyses of the UEc isolates showed a high variability and revealed 16 clusters associated with four phylogenetic groups, namely, groups A, B1, B2, and D. Phylogenetic group B2 was widely associated with the 16 clusters as well as with virulence and fitness genes. The virulence and fitness genes in the UEc isolates, which included fimbriae-, siderophore-, toxin-, and mobility-associated genes, were grouped as occurring at a low, variable, or high frequency. Interestingly, only the papF gene could be amplified from some UEc isolates, and the sequence analysis of the pap operon identified an insertion sequence (IS) element and gene loss. These data suggested pathoadaptability and the development of immune system evasion, which was confirmed by the loss of P fimbriae-associated agglutination in the UEc isolates. E. coli clone O25-ST131 had a prevalence of 20.2% among the UEc isolates; these isolates displayed both a highly MDR profile and the presence of the papGII, fimH, papGIII, iutD, sat, hlyA, and motA genes. In conclusion, the UEc isolates from complicated urinary tract infection (cUTI) were characterized as being MDR, highly genetically diverse, and associated with phylogenetic group B2 and many virulence and fitness genes. Additionally, gene loss and IS elements were identified in some UEc isolates identified as clone O25-ST131.

Here, we aimed to further characterize the mechanisms involved in protoxin (p) Cry1Ac-induced macrophage activation. We demonstrated that pCry1Ac induces MAPK ERK1/2, p38, and JNK phosphorylation in RAW264.7 macrophages. Because MAPK activation is mainly triggered via ligand-receptor interactions, we focused on the identification of potential pCry1Ac-receptor proteins. Flow cytometry and confocal analysis showed specific saturable pCry1Ac-binding to the macrophage surface and evidenced its internalization via the clathrin-pathway. We performed immunoprecipitation assays and identified by MALDI-TOF-TOF several possible pCry1Ac-binding proteins, such as heat shock proteins (HSPs), vimentin, α-enolase, and actin; whose interaction and presence was confirmed, respectively, by ligand blot and Western blot assays. We also detected cell-surface (cs) pCry1Ac-HSP70 colocalization, so HSP70 was chosen for further characterization. Co-immunoprecipitation with HSP70 antibodies followed by Western blot confirmed the pCry1Ac-HSP70 interaction. Furthermore, pretreatment of RAW264.7 cells with HSP70 antibodies reduced pCry1Ac-induced ERK1 phosphorylation and MCP-1 production; thus suggest the functional participation of csHSP70 in pCry1Ac-induced macrophage activation. csHSP70 also was evaluated in peritoneal-cavity (PerC) macrophages of untreated BALB/c mice, interestingly it was found that the predominant population namely large-peritoneal-macrophages (LPM) displayed csHSP70 + hi. Furthermore, the dynamics of PerC macrophage subsets, LPM, and small-peritoneal macrophages (SPM) were evaluated in response to in vivo pCry1Ac stimuli in presence or not of phenylethynesulfonamide (PES) a functional HSP70 inhibitor. It was found that pCry1Ac increased the proportion of SPM CD11b + F4/80 + lowMHCII + csHSP70 + low and markedly reduced the amount of LPM CD11b + F4/80 + hiMHCII-csHSP70 + hi; while PES, partially suppressed this pCry1Ac-induced effect, further suggesting the participation of HSP70 in macrophage activation process. J. Cell. Biochem. 119: 580-598, 2018. © 2017 Wiley Periodicals, Inc.

Conversion of protein -SH groups to disulfides is an early event during protein oxidation, which has prompted great interest in the study of thiol proteins. Chemical carcinogenesis is strongly associated with the formation of reactive oxygen species (ROS). The goal of this study was to detect thiol proteins that are sensitive to ROS generated during diethylnitrosamine (DEN) metabolism in the rat liver. DEN has been widely used to induce experimental hepatocellular carcinoma. We used modified redox-differential gel electrophoresis (redox-DIGE method) and mass spectrometry MALDI-TOF/TOF to identify differential oxidation protein profiles associated with carcinogen exposure. Our analysis revealed a time-dependent increase in the number of oxidized thiol proteins after carcinogen treatment; some of these proteins have antioxidant activity, including thioredoxin, peroxirredoxin 2, peroxiredoxin 6 and glutathione S-transferase alpha-3. According to functional classifications, the identified proteins in our study included chaperones, oxidoreductases, activity isomerases, hydrolases and other protein-binding partners. This study demonstrates that oxidative stress generated by DEN tends to increase gradually through DEN metabolism, causes time-dependent necrosis in the liver and has an oxidative effect on thiol proteins, thereby increasing the number of oxidized thiol proteins. Furthermore, these events occurred during the hepatocarcinogenesis initiation period.

Background Although nowadays it is well known that the human transcriptome can importantly vary according to external or environmental condition, the reflection of this concept when studying oxidative stress and its direct relationship with gene expression profiling during the process of atherogenesis has not been thoroughly achieved. Objective The ability to analyze genome-wide gene expression through transcriptomics has shown that the genome responds dynamically to diverse stimuli. Here, we describe the transcriptome of human vascular smooth muscle cells (hVSMC) stimulated by native and oxidized low-density lipoprotein (nLDL and oxLDL respectively), with the aim of assessing the early molecular changes that induce a response in this cell type resulting in a transcriptomic transformation. This expression has been demonstrated in atherosclerotic plaques in vivo and in vitro, particularly in the light of the oxidative modification hypothesis of atherosclerosis. Approach and Results Total RNA was isolated with TRIzol reagent (Life Technologies) and quality estimated using an Agilent 2100 bioanalyzer. The transcriptome of hVSMC under different experimental conditions (1,5 and 24 hours for nLDL and oxLDL) was obtained using the GeneChip Human Gene 1.0 ST (Affymetrix) designed to measure gene expression of 28,869 well-annotated genes. A fixed fold-change cut-off corresponding to ± 2 was used to identify genes exhibiting the most significant variation and statistical significance (P< 0.05), and 8 genes validated by qPCR using Taqman probes. Conclusions 10 molecular processes were significantly affected in hVSMC: Apoptosis and cell cycle, extracellular matrix remodeling, DNA repair, cholesterol efflux, cGMP biosynthesis, endocytic mechanisms, calcium homeostasis, redox balance, membrane trafficking and finally, the immune response to inflammation. The evidence we present supporting the hypothesis for the involvement of oxidative modification of several processes and metabolic pathways in atherosclerosis is strengthen by the fact that gene expression patterns obtained when hVSMC are incubated for a long period of time in the presence of nLDL, correspond very much the same as when cells are incubated for a short period of time in the presence of chemically modified oxLDL. Our results indicate that under physiological conditions and directly related to specific environmental conditions, LDL particles most probably suffer chemical modifications that initially serve as an alert signal to overcome a harmful stimulus that with time might get transformed to a pathological pattern and therefore consolidate a pathological condition.

Inhibition of angiotensin-converting enzyme (ACE) and antithrombotic properties of peptides released from bovine caseins during fermentation by Lactobacillus casei Shirota and Streptococcus thermophilus were determined. Both species released ACE inhibitory peptides, whereas only Lb. casei Shirota produced antithrombotic activity. The highest thrombin inhibitory activity, 80.7%, was observed at 27 h of fermentation by Lb. casei Shirota. Active peptides were purified by HPLC; seven peptides were obtained, and their resistance to digestive enzymes, pepsin and trypsin, was evaluated. The most active peptide even after the hydrolysis was identified as YQEPVLGPVRGPFPIIV (fragment 193–209 of β-casein): it had an inhibition efficiency ratio for ACE of 0.14%/peptide concentration (μg mL−1), and a thrombin inhibition efficiency ratio of 4.6%/peptide concentration (μg mL−1). This peptide had been previously reported as an ACE-inhibitor, but this is the first time that it is evaluated for its thrombin inhibition activity.

Higher plants form crystals of calcium oxalate in well-controlled conditions. This control is performed in specialized cells by an organic matrix composed by soluble and insoluble water macromolecules. The water-soluble protein matrix associated with the calcium oxalate crystals from bean seed coat (Phaseolus vulgaris) contains many polypeptides of different molecular masses. In this study, we observed that the water-soluble matrix macromolecules strongly inhibited the nucleation of calcium oxalate crystals (this inhibition was concentration dependent). Additionally, two proteins were isolated and purified from the water-soluble matrix with masses of 250 kDa called calcium oxalate macromolecule associated 1 (COMA1) and 27 kDa called calcium oxalate macromolecule associated 2 (COMA2). These proteins were also strong inhibitors of the nucleation of calcium oxalate monohydrate. On the other hand, we found that the modification in the morphology of calcium oxalate crystals due to the presence of water-soluble macromolecules (altogether) affected mainly the {1 2 0} face. Particularly, COMA1 and COMA2 separately had the same influence on the morphology of these crystals.

Ovocleidin-17 (OC17) from Gallus gallus is one of the best candidates to control and regulate the deposition of calcium carbonate in the calcified eggshell layer. Here, the crystal structure of monomeric OC17, determined at a resolution of 1.5 A, was refined to a crystallographic R-factor of 20.1%. This is the first protein directly involved in a non-pathological biomineralization process resolved by x-ray diffraction to date. The protein has a mixed alpha/beta structure containing a single C-type lectin-like domain. However, although OC17 shares the conserved scaffold of the C-type lectins, it does not bind carbohydrates. Nevertheless, in vitro OC17 modifies the crystalline habit of calcium carbonate (CaCO3) and the pattern of crystal growth at intervals of 5-200 microg/ml. Determining the three-dimensional structure of OC17 contributes to a better understanding of the biological behavior of structurally related biomolecules and of the mechanisms involved in eggshell and other mineralization processes.

The purification, crystallization and preliminary X-ray analysis of struthiocalcin 1 (SCA-1), a protein obtained from the intramineral part of ostrich (Struthio camelus) eggshell, is reported.

In this work, we report the crystallization of ovocleidin-17, the major protein of the avian eggshell calcified layer and the preliminary X-ray characterization of this soluble protein which is implied into the CaCO(3) formation of the eggshell in avians. Crystals belong to one of the trigonal space group P3 with cell dimensions a= b= 59.53 A and c = 83.33 A, and alpha=beta= 90 degrees and gamma=120 degrees. Crystals diffract up to 3.0 A.