Protein corona and exosomes: new challenges and prospects

Abstract Recent advances in extracellular vesicle (EVs) detection and isolation methods have led to the development of novel therapeutic modalities. Among different types of EVs, exosomes (Exos) can transfer different signaling biomolecules and exhibit several superior features compared to whole-cell-based therapies. Therapeutic factors are normally loaded into the Exo lumen or attached to their surface for improving the on-target delivery rate and regenerative outcomes. Despite these advantages, there are several limitations in the application of Exos in in vivo conditions. It was suggested that a set of proteins and other biological compounds are adsorbed around Exos in aqueous phases and constitute an external layer named protein corona (PC). Studies have shown that PC can affect the physicochemical properties of synthetic and natural nanoparticles (NPs) after introduction in biofluids. Likewise, PC is generated around EVs, especially Exos in in vivo conditions. This review article is a preliminary attempt to address the interfering effects of PC on Exo bioactivity and therapeutic effects. Video Abstract Graphical Abstrac

Significant role of cationic polymers in drug delivery systems.

Cationic polymers are characterized as the macromolecules that possess positive charges, which can be either inherently in the polymer side chains and/or its backbone. Based on their origins, cationic polymers are divided in two category including natural and synthetic, in which the possessed positive charges are as result of primary, secondary or tertiary amine functional groups that could be protonated in particular situations. Cationic polymers have been employed commonly as drug delivery agents due to their superior encapsulation efficacy, enhanced bioavailability, low toxicity and improved release profile. In this paper, we focus on the most prominent examples of cationic polymers which have been revealed to be applicable in drug delivery systems and we also discuss their general synthesis and surface modification methods as well as their controlled release profile in drug delivery

Cytotoxicity characteristics of green assisted-synthesized superparamagnetic maghemite (γ-Fe2O3) nanoparticles

Magnetic nanoparticles such as Fe3O4 and γ-Fe2O3 are extensively used in medical application, i.e. drug delivery, MRI, etc. Chemical toxicity and side-effect behaviors always play an important role in such applications. Thus, synthesis of such less-toxic compounds with green technology is privilege. In this study, the extract prepared from mango leaves was used for the preparation of iron oxide nanoparticles (γ-Fe2O3) using FeSO4 as iron source with the green-assisted route. The X-ray diffraction pattern indicated single-phase formation with the average crystallite size of 7 ± 2 nm. HRTEM micrographs indicated a dot-cloud-surrounded like particles ranging from 1 to 12 nm. Fourier Transform Infrared (FT-IR) spectroscopy showed two absorption bands at 457 and 634 cm−1, which are attributed to octahedral and tetrahedral sites of Fe–O band, respectively. A vibrating sample magnetometer (VSM) indicated a saturation magnetization (Ms) value about 53 emu/g with negligible coercivity (Hc), suggesting superparamagnetic behavior of the synthesized nanoparticles. The cytotoxicity was evaluated by exposing the breast cancer cell type (MCF7) to different concentrations of the γ-Fe2O3 nanoparticles. MTT assay results revealed that the growth and survival of MCF7 cells directly depend on the concentration of synthesized iron oxide nanoparticles. It was found that up to concentration of 200 µg/mL, cell survival has not yet reached 50%, which indicates the safety of nanoparticles and lack of toxicity

SRL-Coated PAMAM Dendrimer Nano-Carrier for Targeted Gene Delivery to the Glioma Cells and Competitive Inhibition by Lactoferrin

Abstract Glioma, as a primary tumor of central nervous system, is the main cause of death in patients with brain cancer. Therefore, development of an efficient strategy for treatment of glioma is worthy. The aim of the current study was to develop a SRL peptide-coated dendrimer as a novel dual gene delivery system for targeting the LRP receptor, an up-regulated gene in both BBB and glioma cells. To perform this investigation, our newly developed nanocarrier (PAMAM-PEG-SRL) was used for gene delivery to C6 glioma cell lines. DNA (GFP) was loaded in these functionalized nanoparticles and their cellular uptake/distribution and gene transfection efficacy was evaluated by fluorescence and confocal microscopy. In vitro studies showed that SRL-modified nanoparticles have good transfection efficacy. Results revealed improved gene transfection efficiency of newly-synthesized delivery system. We also found that lactoferrin, as a LRP ligand, reduced the gene transfection efficacy of the delivery system due to its higher affinity compared to SRL peptides (Competitive inhibition). The present results suggest that the synthesized delivery system has the potential to be used as an alternative targeted drug delivery system for brain tumors

Advanced stage, high-grade primary tumor ovarian cancer: a multi-omics dissection and biomarker prediction process

Abstract Ovarian cancer (OC) incidence and mortality rates continue to escalate globally. Early detection of OC is challenging due to extensive metastases and the ambiguity of biomarkers in advanced High-Grade Primary Tumors (HGPTs). In the present study, we conducted an in-depth in silico analysis in OC cell lines using the Gene Expression Omnibus (GEO) microarray dataset with 53 HGPT and 10 normal samples. Differentially-Expressed Genes (DEGs) were also identified by GEO2r. A variety of analyses, including gene set enrichment analysis (GSEA), ChIP enrichment analysis (ChEA), eXpression2Kinases (X2K) and Human Protein Atlas (HPA), elucidated signaling pathways, transcription factors (TFs), kinases, and proteome, respectively. Protein–Protein Interaction (PPI) networks were generated using STRING and Cytoscape, in which co-expression and hub genes were pinpointed by the cytoHubba plug-in. Validity of DEG analysis was achieved via Gene Expression Profiling Interactive Analysis (GEPIA). Of note, KIAA0101, RAD51AP1, FAM83D, CEP55, PRC1, CKS2, CDCA5, NUSAP1, ECT2, and TRIP13 were found as top 10 hub genes; SIN3A, VDR, TCF7L2, NFYA, and FOXM1 were detected as predominant TFs in HGPTs; CEP55, PRC1, CKS2, CDCA5, and NUSAP1 were identified as potential biomarkers from hub gene clustering. Further analysis indicated hsa-miR-215-5p, hsa-miR-193b-3p, and hsa-miR-192-5p as key miRNAs targeting HGPT genes. Collectively, our findings spotlighted HGPT-associated genes, TFs, miRNAs, and pathways as prospective biomarkers, offering new avenues for OC diagnostic and therapeutic approaches

Cell surface GRP78: An emerging imaging marker and therapeutic target for cancer

As one of the deadliest diseases, cancer frequently resists existing therapeutics because they do not target all cells within a progressing tumor, for example both tumor stem and proliferating cells. This frequently results in enrichment of invasive and metastatic drug-resistant tumor cells subpopulations, cancer recurrence and eventually, patient mortality. Thus, there is an urgent need to identify specific markers, by which the targeted imaging and/or therapeutic "guided missile"-like agents can specifically detect and/or eradicate all cancer cells within a heterogeneous tumor, while leaving the normal cells intact. As a member of heat shock protein 70 (HSP70) superfamily, glucose regulated protein 78 (GRP78) has been documented as a molecular chaperone in the endoplasmic reticulum (ER) which mainly responds to ER stresses in normal cells. There is over-expression of GRP78 on the surface of cancer cells and angiogenic endothelial cells, which makes it a promising target for different types of peptides and antibodies that can be employed for targeted cancer therapy or imaging. In this review, we discuss the biological processes, functional importance and translocation mechanisms of cell surface GRP78 (csGRP78) in tumor cells. As a cancer biomarker, we also review the potential applications of csGRP78 targeted therapy and imaging and finally we suggest a brief roadmap ahead of csGRP78 targeting for targeted theranostic implications

Synthesis of a novel PEGDGA-coated hPAMAM complex as an efficient and biocompatible gene delivery vector: an <i>in vitro</i> and <i>in vivo</i> study

<p>hPAMAM/DNA polyplexes, compared to viral vectors, display unique characteristics including more safety, less immune response outcomes, a simpler synthesis and an easier process. Given the importance of these polymers, hPAMAM coated with the PEGDGA copolymer was developed as a promising non-viral gene carrier. In the present study, a new complex of hPAMAM, PEGDGA-modified hyperbranched polyamidoamine (hPAMAM), was established as a versatile non-viral gene vector. The hPAMAM polymer was synthesized by using a modified one-pot method. The resulting hPAMAM–PEGDGA polymer was able to efficiently protect encapsulated-DNA against degradation for over 2 h. In addition to low cytotoxicity, the transfection efficiency of hPAMAM–PEGDGA represented much higher (<i>p</i> < 0.05) than that of Lipofectamine 2000 in both MCF7 and MDA-MB231 cells (an approximately 4.5-fold increase). Cellular uptake of hPAMAM–PEGDGA in MDA-MB231 cells, 254.79 ± 2.1, was significantly higher than that in MCF7 cells, 51.61 ± 6.1 (<i>p</i> < 0.05). EMA-labeled DNA can be clearly observed in the tumor tissue of mice receiving hPAMAM-PEGDGA/EMA-labeled DNA. However, a significant number of fluorescent spots can be found in the tumor tissue of mice receiving hPAMAM/DNA, when compared to those treated with naked hPAMAM/DNA. It has been observed that GFP is expressed more highly in hPAMAM-PEGDGA/EMA-labeled/DNA than the one in PAMAM/DNA. The results indicated that hPAMAM-PEGDGA-mediated gene delivery to breast cancer cells is a feasible and effective strategy that may offer a new therapeutic avenue as a non-viral gene delivery carrier. Notably, According to these findings, this newly-introduced copolymer, the hPAMAM–PEGDGA complex, has proved to be a promising strategy for drug or gene delivery to tissues or cell types of interest, particularly to triple-negative breast cancer.</p