Enhanced Chemotherapeutic Efficacy of Paclitaxel Nanoparticles Co-delivered with MicroRNA-7 by Inhibiting Paclitaxel-Induced EGFR/ERK pathway Activation for Ovarian Cancer Therapy

MicroRNA nanoformulation: a promising approach to anti-tumour activity

Cancer is a major cause of morbidity and mortality, making it one of the most debilitating diseases in our time. Despite advancements in therapeutic strategies, the development of chemoresistance and the occurrence of secondary tumours pose significant challenges. While several promising anti-tumour agents have been identified, their clinical utility is often limited due to toxicity and associated side effects. MicroRNAs (mi-RNAs) are critical regulators of gene expression, and their altered levels are closely linked to cancer development and progression. Although some microRNAs have shown potential as biomarkers for cancer detection, their integration into routine clinical practice has yet to be realized. Numerous candidate microRNAs exhibit therapeutic potential for cancer treatment; however, further research is needed to create efficient, patient-compliant, and customized drug delivery systems. In recent decades, various nanotechnology platforms have successfully transitioned to clinical trials, particularly in the field of RNA nanotechnology. Several RNA nanoparticles have been developed to address key challenges in vivo for targeting cancer, demonstrating favourable biodistribution characteristics. Studies have shown that RNA nanoparticles, characterized by precise stoichiometry and homogeneity, can effectively target tumour cells while avoiding aggregation in normal, healthy tissues following systemic injection. Animal models have demonstrated that RNA nanoparticles can deliver therapeutics such as siRNA and anti-microRNA, effectively inhibiting tumour growth. Using nanoparticles conjugated with antibodies and/or peptides enhances the targeted delivery and sustained release of microRNAs and anti-microRNAs, which may reduce the required therapeutic dosage and minimize systemic and cellular damage. This review focuses on developing microRNA nanoformulations to improve cellular uptake, bioavailability, and accumulation at tumour sites, assessing their potential anti-tumour efficacy against various types of malignancies. The significance of these advancements in clinical oncology cannot be overstated.

Nanoparticle co-delivery of carboplatin and PF543 restores platinum sensitivity in ovarian cancer models through inhibiting platinum-induced pro-survival pathway activation

Resistance to platinum-based chemotherapy is the major cause of poor prognosis and cancer-associated mortality in ovarian cancer patients, so novel therapeutic strategies to restore platinum sensitivity are needed to improve patient outcomes. Sphingosine Kinase (SphK) 1 is involved in regulating multiple pro-survival pathways, key mediators in the sensitivity of tumor cells toward platinum. By encapsulating CBP and the SphK1 inhibitor PF543 in PLGA (poly lactic-co-glycolic acid) nanoparticles, a dual-drug delivery system (C/PNPs) was formed to simultaneously deliver CBP and PF543. The physicochemical characteristics, cell uptake rate and biodistribution behavior of C/PNPs were evaluated. Then the anti-tumor ability of C/PNPs in vitro and in vivo was further investigated. The C/PNPs could deliver CBP and PF543 simultaneously to a platinum-insensitive cell line (SKOV3) both in vitro and in vivo. Furthermore, benefiting from the enhanced permeability and retention (EPR) effect of PLGA NPs, C/PNPs exhibited an improved tumor region accumulation. As a result, a synergistic anti-tumor effect was found in the SKOV3 tumor-bearing mice, with tumor volume inhibiting rates of 84.64% and no side effects in major organs. The mechanistic studies confirmed that the inhibition of SphK1 by PF543 sensitized SKOV3 cells to CBP chemotherapy, partly by inhibiting the CBP-induced activation of pro-survival pathways, including ERK, AKT and STAT3 signaling. Our study reveals that C/PNPs can serve as an efficient dual-drug delivery system to restore platinum sensitivity in ovarian cancer models partly through inhibiting platinum-induced pro-survival pathway activation.

Mapping the function of MicroRNAs as a critical regulator of tumor-immune cell communication in breast cancer and potential treatment strategies

Among women, breast cancer ranks as the most prevalent form of cancer, and the presence of metastases significantly reduces prognosis and diminishes overall survival rates. Gaining insights into the biological mechanisms governing the conversion of cancer cells, their subsequent spread to other areas of the body, and the immune system's monitoring of tumor growth will contribute to the advancement of more efficient and targeted therapies. MicroRNAs (miRNAs) play a critical role in the interaction between tumor cells and immune cells, facilitating tumor cells' evasion of the immune system and promoting cancer progression. Additionally, miRNAs also influence metastasis formation, including the establishment of metastatic sites and the transformation of tumor cells into migratory phenotypes. Specifically, dysregulated expression of these genes has been associated with abnormal expression of oncogenes and tumor suppressor genes, thereby facilitating tumor development. This study aims to provide a concise overview of the significance and function of miRNAs in breast cancer, focusing on their involvement as tumor suppressors in the antitumor immune response and as oncogenes in metastasis formation. Furthermore, miRNAs hold tremendous potential as targets for gene therapy due to their ability to modulate specific pathways that can either promote or suppress carcinogenesis. This perspective highlights the latest strategies developed for miRNA-based therapies.

Recent trends in the delivery of RNA drugs: Beyond the liver, more than vaccine

RNAs are known for versatile functions and therapeutic utility. They have gained significant interest since the approval of several RNA drugs, including COVID-19 mRNA vaccines and therapeutic agents targeting liver diseases. There are increasing expectations for a new class of RNA drugs for broader applications. Successful development of RNA drugs for new applications hinges on understanding their diverse functions and structures. In this review, we explore the last five years of literature to understand current approaches to formulate a spectrum of RNA drugs, focusing on new efforts to expand their applications beyond vaccines and liver diseases.

VNP20009-Abvec-Igκ-MIIP suppresses ovarian cancer progression by modulating Ras/MEK/ERK signaling pathway

Ovarian cancer poses a significant threat to women's health, with conventional treatment methods encountering numerous limitations, and the emerging engineered bacterial anti-tumor strategies offer newfound hope for ovarian cancer treatment. In this study, we constructed the VNP20009-Abvec-Igκ-MIIP (VM) engineered strain and conducted initial assessments of its in vitro growth performance and the expression capability of migration/invasion inhibitory protein (MIIP). Subsequently, ID8 ovarian cancer cells and mouse cancer models were conducted to investigate the impact of VM on ovarian cancer. Our results revealed that the VM strain demonstrated superior growth performance, successfully invaded ID8 ovarian cancer cells, and expressed MIIP, consequently suppressing cell proliferation and migration. Moreover, VM specifically targeted tumor sites and expressed MIIP which further reduced the tumor volume of ovarian cancer mice (p < 0.01), via the downregulation of epidermal growth factor receptor (EGFR), Ras, p-MEK, and p-ERK. The downregulation of the PI3K/AKT signaling pathway and the decrease in Bcl-2/Bax levels also indicated VM's apoptotic potency on ovarian cancer cells. In summary, our research demonstrated that VM exhibits promising anti-tumor effects both in vitro and in vivo, underscoring its potential for clinical treatment of ovarian cancer. KEY POINTS: • This study has constructed an engineered strain of Salmonella typhimurium capable of expressing anticancer proteins • The engineered bacteria can target and colonize tumor sites in vivo • VM can inhibit the proliferation, migration, and invasion of ovarian cancer cells.

Exploring the mechanism by which quercetin re-sensitizes breast cancer to paclitaxel: network pharmacology, molecular docking, and experimental verification

This study is aimed to explore the potential molecular mechanism of quercetin reversing paclitaxel (PTX) resistance in breast cancer (BC) by network pharmacology, molecular docking, and experimental verification. Pharmacological platform databases are used to predict quercetin targets and BC PTX-resistance genes and constructed the expression profile of quercetin chemosensitization. The overlapping targets were input into the STRING database and used Cytoscape v3.9.0 to construct the protein-protein interaction (PPI) network. Subsequently, these targets were performed with Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment analyses and molecular docking. Finally, we further detected the potential role of quercetin in improving PTX sensitivity in BC in vitro experiments. Compounds and targets screening hinted that 220 quercetin predicted targets, 244 BC PTX resistance-related genes, and 66 potential sensitive target genes (PSTGs). Network pharmacology screening revealed the top-15 crucial targets in PPI network of quercetin reversing the sensitivity of BC to PTX. KEGG analysis revealed that they were mainly enriched in the EGFR/ERK signaling pathway. Molecular docking showed that both quercetin and PTX could stably bind to the key targets in the EGFR/ERK signaling pathway. In vitro experiments further confirmed that quercetin inhibited the key targets in the EGFR/ERK axis to the suppression of cell proliferation and promotion of apoptosis in PTX-resistance BC cells, and restoring the activity of the resistant cells to PTX. Our results suggested that quercetin increased the sensitivity of BC to PTX through inhibiting EGFR/ERK axis, and it is an effective treatment for reversing PTX resistance.

RSK4 confers paclitaxel resistance to ovarian cancer cells, which is resensitized by its inhibitor BI-D1870

Many ovarian cancers initially respond well to chemotherapy, but often become drug-resistant after several years. Therefore, analysis of drug resistance mechanisms and overcoming resistance are urgently needed. Paclitaxel is one of the first-choice and widely-used drugs for ovarian cancer, but like most drugs, drug resistance is observed in subsequent use. RSK4 is known as a tumor-suppressor, however, it has increasingly been reported to lead to drug resistance. Here, we found that RSK4 expression was elevated in paclitaxel-resistant ovarian cancer cells using DNA microarray, quantitative real-time PCR, and western blotting analysis. We examined the contribution of RSK4 to paclitaxel resistance and found that paclitaxel sensitivity was restored by RSK inhibitor co-treatment. We analyzed the mechanism by which resistance is developed when RSK4 level is elevated, and accelerated phosphorylation of the downstream translation factor eIF4B was discovered. In the Kaplan-Meier plot, the overall survival time was longer with RSK4 high, supporting its role as a tumor suppressor, as in previous findings, but the tendency was reversed when focusing on paclitaxel treatment. In addition, RSK4 levels were higher in non-responders than in responders in the ROC plotter. Finally, external expression of RSK4 in ovarian cancer cells increased the cell viability under paclitaxel treatment. These findings suggest that RSK4 may contribute to paclitaxel resistance, and that co-treatment with RSK4 inhibitors is effective treatment of paclitaxel-resistant ovarian cancer in which RSK4 is elevated.

Progress in construction and release of natural polysaccharide-platinum nanomedicines: A review

Natural polysaccharides are natural biomaterials that have become candidate materials for nano-drug delivery systems due to their excellent biodegradability and biocompatibility. Platinum (Pt) drugs have been widely used in the clinical therapy for various solid tumors. However, their extensive systemic toxicity and the drug resistance acquired by cancer cells limit the applications of platinum drugs. Modern nanobiotechnology provides the possibility for targeted delivery of platinum drugs to the tumor site, thereby minimizing toxicity and optimizing the efficacies of the drugs. In recent years, numerous natural polysaccharide-platinum nanomedicine delivery carriers have been developed, such as nanomicelles, nanospheres, nanogels, etc. Herein, we provide an overview on the construction and drug release of natural polysaccharide-Pt nanomedicines in recent years. Current challenges and future prospectives in this field are also put forward. In general, combining with irradiation and tumor microenvironment provides a significant research direction for the construction of natural polysaccharide-platinum nanomedicines and the release of responsive drugs in the future.

Resistance of breast cancer cells to paclitaxel is associated with low expressions of miRNA-186 and miRNA-7

Aim: Neo-adjuvant chemotherapy is a common approach for the complex treatment of breast cancer (BC) and paclitaxel (PTX) is frequently included in the therapeutic regimen. However, the effect of PTX-based treatment is hard to predict precisely based on routinely used markers. As microRNAs are considered a new promising class of biomarkers, the link between miRNA expression and PTX resistance of BC cells needs to be well investigated. This study aimed at the identification of miRNAs associated with responses of BC cells to PTX. Methods: Intrinsic PTX sensitivity and miRNA profiling were assayed in five BC cell lines to identify candidate miRNAs. Selected miRNA (n. 15) expressions were analyzed by real-time-quantitative polymerase chain reaction (RT-qPCR) in BC tissue samples (n. 31) obtained from a diagnostic biopsy. Results were analyzed in the context of the effect of two cycles of PTX and the effect of the completed scheme of neoadjuvant therapy. The study's design facilitated the evaluation of the effect of PTX on cells and the identification of features of the microRNA expression profiles associated exclusively with sensitivity to this drug. Results: miR-186 and miR-7 expression in BC tissues was higher in patients with better outcomes of PTX-based neoadjuvant therapy. Conclusion: High expressions of miR-186 and miR-7 are associated with good response to PTX, whereas their low expressions may be associated with resistance to PTX in BC, indicating the possibility of developing innovative test systems for the prediction of the PTX response, which can be used before the start of neo-adjuvant chemotherapy for BC.

Current advances in nanoformulations of therapeutic agents targeting tumor microenvironment to overcome drug resistance

The tumor microenvironment (TME) plays a pivotal role in cancer development and progression. In this line, revealing the precise mechanisms of the TME and associated signaling pathways of tumor resistance could pave the road for cancer prevention and efficient treatment. The use of nanomedicine could be a step forward in overcoming the barriers in tumor-targeted therapy. Novel delivery systems benefit from enhanced permeability and retention effect, decreasing tumor resistance, reducing tumor hypoxia, and targeting tumor-associated factors, including immune cells, endothelial cells, and fibroblasts. Emerging evidence also indicates the engagement of multiple dysregulated mediators in the TME, such as matrix metalloproteinase, vascular endothelial growth factor, cytokines/chemokines, Wnt/β-catenin, Notch, Hedgehog, and related inflammatory and apoptotic pathways. Hence, investigating novel multitargeted agents using a novel delivery system could be a promising strategy for regulating TME and drug resistance. In recent years, small molecules from natural sources have shown favorable anticancer responses by targeting TME components. Nanoformulations of natural compounds are promising therapeutic agents in simultaneously targeting multiple dysregulated factors and mediators of TME, reducing tumor resistance mechanisms, overcoming interstitial fluid pressure and pericyte coverage, and involvement of basement membrane. The novel nanoformulations employ a vascular normalization strategy, stromal/matrix normalization, and stress alleviation mechanisms to exert higher efficacy and lower side effects. Accordingly, the nanoformulations of anticancer monoclonal antibodies and conventional chemotherapeutic agents also improved their efficacy and lessened the pharmacokinetic limitations. Additionally, the coadministration of nanoformulations of natural compounds along with conventional chemotherapeutic agents, monoclonal antibodies, and nanomedicine-based radiotherapy exhibits encouraging results. This critical review evaluates the current body of knowledge in targeting TME components by nanoformulation-based delivery systems of natural small molecules, monoclonal antibodies, conventional chemotherapeutic agents, and combination therapies in both preclinical and clinical settings. Current challenges, pitfalls, limitations, and future perspectives are also discussed.

MiRNA dysregulation underlying common pathways in type 2 diabetes and cancer development: an Italian Association of Medical Oncology (AIOM)/Italian Association of Medical Diabetologists (AMD)/Italian Society of Diabetology (SID)/Italian Society of Endocrinology (SIE)/Italian Society of Pharmacology (SIF) multidisciplinary critical view

Increasing evidence suggests that patients with diabetes, particularly type 2 diabetes (T2D), are characterized by an increased risk of developing different types of cancer, so cancer could be proposed as a new T2D-related complication. On the other hand, cancer may also increase the risk of developing new-onset diabetes, mainly caused by anticancer therapies. Hyperinsulinemia, hyperglycemia, and chronic inflammation typical of T2D could represent possible mechanisms involved in cancer development in diabetic patients. MicroRNAs (miRNAs) are a subset of non-coding RNAs, ⁓22 nucleotides in length, which control the post-transcriptional regulation of gene expression through both translational repression and messenger RNA degradation. Of note, miRNAs have multiple target genes and alteration of their expression has been reported in multiple diseases, including T2D and cancer. Accordingly, specific miRNA-regulated pathways are involved in the pathogenesis of both conditions. In this review, a panel of experts from the Italian Association of Medical Oncology (AIOM), Italian Association of Medical Diabetologists (AMD), Italian Society of Diabetology (SID), Italian Society of Endocrinology (SIE), and Italian Society of Pharmacology (SIF) provide a critical view of the evidence about the involvement of miRNAs in the pathophysiology of both T2D and cancer, trying to identify the shared miRNA signature and pathways able to explain the strong correlation between the two conditions, as well as to envision new common pharmacological approaches.

miRNAs are now starring in "No Time to Die: Overcoming the chemoresistance in cancer"

Cancer is a leading cause of death globally, with about 19.3 million new cases reported each year. Current therapies for cancer management include-chemotherapy, radiotherapy, and surgery. However, they are loaded with side effects and tend to cause toxicity in the patient's body posttreatment, ultimately hindering the response towards the treatment building up resistance. This is where noncoding RNAs such as miRNAs help provide us with a helping hand for taming the chemoresistance and providing potential holistic cancer management. MicroRNAs are promising targets for anticancer therapy as they perform critical regulatory roles in various signaling cascades related to cell proliferation, apoptosis, migration, and invasion. Combining miRNAs and anticancer drugs and devising a combination therapy has managed cancer well in various independent studies. This review aims to provide insights into how miRNAs play a mechanistic role in cancer development and progression and regulate drug resistance in various types of cancers. Furthermore, next-generation novel therapies using miRNAs in combination with anticancer treatments in multiple cancers have been put forth and how they improve the efficacy of the treatments. Exemplary studies currently in the preclinical and clinical models have been summarized. Ultimately, we briefly talk through the challenges that come forward with it and minimize them.

Current Update on Nanotechnology-Based Approaches in Ovarian Cancer Therapy

Ovarian cancer is one of the leading causes of cancer-related deaths among women. The drawbacks of conventional therapeutic strategies encourage researchers to look for alternative strategies, including nanotechnology. Nanotechnology is one of the upcoming domains of science that is rechanneled towards targeted cancer therapy and diagnosis. Nanocarriers such as dendrimers, liposomes, polymer micelles, and polymer nanoparticles present distinct surface characteristics in morphology, surface chemistry, and mode of action that help differentiate normal and malignant cells, which paves the way for target-specific drug delivery. Similarly, nanoparticles have been strategically utilized as efficacious vehicles to deliver drugs that alter the epigenetic modifications in epigenetic therapy. Some studies suggest that the use of specialized target-modified nanoparticles in siRNA-based nanotherapy prevents internalization and improves the antitumor activity of siRNA by ensuring unrestrained entry of siRNA into the tumor vasculature and efficient intracellular delivery of siRNA. Moreover, research findings highlight the significance of utilizing nanoparticles as depots for photosensitive drugs in photodynamic therapy. The applicability of nanoparticles is further extended to medical imaging. They serve as contrast agents in combination with conventional imaging modalities such as MRI, CT, and fluorescence-based imaging to produce vivid and enhanced images of tumors. Therefore, this review aims to explore and delve deeper into the advent of various nanotechnology-based therapeutic and imaging techniques that provide non-invasive and effective means to tackle ovarian cancers.

Identification of the miR-423-3p/VLDLR Regulatory Network for Glioma Using Transcriptome Analysis

As the most prevalent primary CNS tumor, glioma is characterized by high mortality and morbidity. This research aims to investigate glioma-associated microRNAs (miRNAs) and their target mRNAs, as well as to explore their biological functions in gliomas. The Gene Expression Omnibus (GEO) database was applied to acquire the GSE112264 miRNA microarray dataset and the GSE15824 mRNA dataset. We selected samples from the GSE112264 dataset and the GSE15824 to identify differently expressed miRNAs (DE-miRNAs) as well as differentially expressed mRNAs (DEGs), respectively. Next, the intersections of mRNA and target mRNAs of miRNA were selected, and we constructed miRNA-mRNA regulation networks. These DEGs were selected for Gene Oncology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses by conducting the package clusterProfiler. After conducting Cytoscape software, a protein-protein interaction (PPI) network was created. Next, survival analysis of the miR-423-3p was confirmed by conducting TCGA database. Subsequently, Quantitative real-time PCR (qRT-PCR) was conducted to verify miR-423-3p's expression. Finally, miR-423-3p's biological functions of in effecting the cell proliferative, migratory, and invasive capabilities of glioma were investigated by performing Cell Counting Kit-8 (CCK-8) and Transwell assays. Our analysis elucidated a novel miRNA-mRNA regulatory network related to glioma carcinogenesis, which may be considered as future therapeutic biomarkers for glioma.

Advancements in Polymeric Nanocarriers to Mediate Targeted Therapy against Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is a destructive disease with a poor prognosis, low survival rate and high rate of metastasis. It comprises 15% of total breast cancers and is marked by deficiency of three important receptor expressions, i.e., progesterone, estrogen, and human epidermal growth factor receptors. This absence of receptors is the foremost cause of current TNBC therapy failure, resulting in poor therapeutic response in patients. Polymeric nanoparticles are gaining much popularity for transporting chemotherapeutics, genes, and small-interfering RNAs. Due to their exclusive properties such as great stability, easy surface modification, stimuli-responsive and controlled drug release, ability to condense more than one therapeutic moiety inside, tumor-specific delivery of payload, enhanced permeation and retention effect, present them as ideal nanocarriers for increasing efficacy, bioavailability and reducing the toxicity of therapeutic agents. They can even be used as theragnostic agents for the diagnosis of TNBC along with its treatment. In this review, we discuss the limitations of already existing TNBC therapies and highlight the novel approach to designing and the functionalization of polymeric nanocarriers for the effective treatment of TNBC.

Deregulated miRNA clusters in ovarian cancer: Imperative implications in personalized medicine

Ovarian cancer (OC) is one of the most common and fatal types of gynecological cancer. OC is usually detected at the advanced stages of the disease, making it highly lethal. miRNAs are single-stranded, small non-coding RNAs with an approximate size ranging around 22 nt. Interestingly, a considerable proportion of miRNAs are organized in clusters with miRNA genes placed adjacent to one another, getting transcribed together to result in miRNA clusters (MCs). MCs comprise two or more miRNAs that follow the same orientation during transcription. Abnormal expression of the miRNA cluster has been identified as one of the key drivers in OC. MC exists both as tumor-suppressive and oncogenic clusters and has a significant role in OC pathogenesis by facilitating cancer cells to acquire various hallmarks. The present review summarizes the regulation and biological function of MCs in OC. The review also highlights the utility of abnormally expressed MCs in the clinical management of OC.

Kill two birds with one stone: Engineered exosome-mediated delivery of cholesterol modified YY1-siRNA enhances chemoradiotherapy sensitivity of glioblastoma

Glioblastoma (GBM) is the most malignant tumor of the central nervous system in adults. Irradiation (IR) and temozolomide (TMZ) play an extremely important role in the treatment of GBM. However, major impediments to effective treatment are postoperative tumor recurrence and acquired resistance to chemoradiotherapy. Our previous studies confirm that Yin Yang 1 (YY1) is highly expressed in GBM, whereby it is associated with cell dedifferentiation, survival, and therapeutic resistance. Targeted delivery of small interfering RNA (siRNA) without blood-brain barrier (BBB) restriction for eradication of GBM represents a promising approach for therapeutic interventions. In this study, we utilize the engineering technology to generate T7 peptide-decorated exosome (T7-exo). T7 is a peptide specifically binding to the transferrin receptor. T7-exo shows excellent packaging and protection of cholesterol-modified Cy3-siYY1 while quickly releasing payloads in a cytoplasmic reductive environment. The engineered exosomes T7-siYY1-exo could deliver more effciently to GBM cells both in vitro and in vivo. Notably, in vitro experiments demonstrate that T7-siYY1-exo can enhance chemoradiotherapy sensitivity and reverse therapeutic resistance. Moreover, T7-siYY1-exo and TMZ/IR exert synergistic anti-GBM effect and significantly improves the survival time of GBM bearing mice. Our findings indicate that T7-siYY1-exo may be a potential approach to reverse the chemoradiotherapy resistance in GBM.

The Yin and Yang of epigenetics in the field of nanoparticles

Nanoparticles (NPs) have become a very exciting research avenue, with multitudinous applications in various fields, including the biomedical one, whereby they have been gaining considerable interest as drug carriers able to increase bioavailability, therapeutic efficiency and specificity of drugs. Epigenetics, a complex network of molecular mechanisms involved in gene expression regulation, play a key role in mediating the effect of environmental factors on organisms and in the etiology of several diseases (e.g., cancers, neurological disorders and cardiovascular diseases). For many of these diseases, epigenetic therapies have been proposed, whose application is however limited by the toxicity of epigenetic drugs. In this review, we will analyze two aspects of epigenetics in the field of NPs: the first is the role that epigenetics play in mediating nanotoxicity, and the second is the possibility of using NPs for delivery of "epi-drugs" to overcome their limitations. We aim to stimulate discussion among specialists, specifically on the potential contribution of epigenetics to the field of NPs, and to inspire newcomers to this exciting technology.

Combined Therapeutics for Atherosclerosis Treatment Using Polymeric Nanovectors

Atherosclerosis is an underlying risk factor in cardiovascular diseases (CVDs). The combination of drugs with microRNAs (miRNA) inside a single nanocarrier has emerged as a promising anti-atherosclerosis strategy to achieve the exploitation of their complementary mechanisms of action to achieve synergistic therapeutic effects while avoiding some of the drawbacks associated with current systemic statin therapies. We report the development of nanometer-sized polymeric PLGA nanoparticles (NPs) capable of simultaneously encapsulating and delivering miRNA-124a and the statin atorvastatin (ATOR). The polymeric NPs were functionalized with an antibody able to bind to the vascular adhesion molecule-1 (VCAM1) overexpressed in the inflamed arterial endothelium. The dual-loaded NPs were non-toxic to cells in a large range of concentrations, successfully attached overexpressed VCAM receptors and released the cargoes in a sustainable manner inside cells. The combination of both ATOR and miRNA drastically reduced the levels of proinflammatory cytokines such as IL-6 and TNF-α and of reactive oxygen species (ROS) in LPS-activated macrophages and vessel endothelial cells. In addition, dual-loaded NPs precluded the accumulation of low-density lipoproteins (LdL) inside macrophages as well as morphology changes to a greater extent than in single-loaded NPs. The reported findings validate the present NPs as suitable delivery vectors capable of simultaneously targeting inflamed cells in atherosclerosis and providing an efficient approach to combination nanomedicines.

Surface-fill hydrogel attenuates the oncogenic signature of complex anatomical surface cancer in a single application

Tumours growing in a sheet-like manner on the surface of organs and tissues with complex topologies represent a difficult-to-treat clinical scenario. Their complete surgical resection is difficult due to the complicated anatomy of the diseased tissue. Residual cancer often responds poorly to systemic therapy and locoregional treatment is hindered by the limited accessibility to microscopic tumour foci. Here we engineered a peptide-based surface-fill hydrogel (SFH) that can be syringe- or spray-delivered to surface cancers during surgery or used as a primary therapy. Once applied, SFH can shape change in response to alterations in tissue morphology that may occur during surgery. Implanted SFH releases nanoparticles composed of microRNA and intrinsically disordered peptides that enter cancer cells attenuating their oncogenic signature. With a single application, SFH shows efficacy in four preclinical models of mesothelioma, demonstrating the therapeutic impact of the local application of tumour-specific microRNA, which might change the treatment paradigm for mesothelioma and possibly other surface cancers.

Asynchronous blockade of PD-L1 and CD155 by polymeric nanoparticles inhibits triple-negative breast cancer progression and metastasis

PD-L1/PD-1 blockade therapy shows durable responses to triple-negative breast cancer (TNBC), but the response rate is low. CD155 promotes tumor metastasis intrinsically and modulates the immune response extrinsically as the ligand of DNAM-1 (costimulatory receptor) and TIGIT/CD96 (coinhibitory receptors). Herein, we verified that TNBC cells coexpressed PD-L1 and CD155. By examining the receptors of PD-L1 and CD155 on TNBC tumor-infiltrating lymphocytes (TILs) over time, we observed that PD-1 and DNAM-1 were upregulated early, whereas CD96 and TIGIT were upregulated late in CD8⁺ TILs. Based on these findings, we developed CD155 siRNA (siCD155)-loaded mPEG-PLGA-PLL (PEAL) nanoparticles (NPs) coated with PD-L1 blocking antibodies (P/PEAL_siCD155) to asynchronously block PD-L1 and CD155 in a spatiotemporal manner. P/PEAL_siCD155 maximized early-stage CD8⁺ T cell immune surveillance against 4T1 tumor, whereas reversed inhibition status of the late stage CD8⁺ T cells to prevent 4T1 tumor immune escape. In addition, the combination of P/PEAL_siCD155 and tumor-specific CD8 T cells induced immunogenic cell death (ICD) of 4T1 cells to further boost immune checkpoint therapy. Most importantly, P/PEAL_siCD155 displayed excellent TNBC targeting and induced CD8⁺ TILs-dominant intratumor antitumor immunity to efficiently inhibit TNBC progression and metastasis with excellent safety in a syngeneic 4T1 orthotopic TNBC tumor model.

MicroRNA Therapeutics in Cancer: Current Advances and Challenges

Simple Summary

Cancer is a complex disease associated with deregulation of numerous genes. In addition, redundant cellular pathways limit efficiency of monotarget drugs in cancer therapy. MicroRNAs are a class of gene expression regulators, which often function by targeting multiple genes. This feature makes them a double-edged sword (a) as attractive targets for anti-tumor therapy and concomitantly (b) as risky targets due to their potential side effects on healthy tissues. As for conventional antitumor drugs, nanocarriers have been developed to circumvent the problems associated with miRNA delivery to tumors. In this review, we highlight studies that have established the pre-clinical proof-of concept of miRNAs as relevant therapeutic targets in oncology. Particular attention was brought to new strategies based on nanovectorization of miRNAs as well as to the perspectives for their applications.

Abstract

The discovery of microRNAs (miRNAs) in 1993 has challenged the dogma of gene expression regulation. MiRNAs affect most of cellular processes from metabolism, through cell proliferation and differentiation, to cell death. In cancer, deregulated miRNA expression leads to tumor development and progression by promoting acquisition of cancer hallmark traits. The multi-target action of miRNAs, which enable regulation of entire signaling networks, makes them attractive tools for the development of anti-cancer therapies. Hence, supplementing downregulated miRNA by synthetic oligonucleotides or silencing overexpressed miRNAs through artificial antagonists became a common strategy in cancer research. However, the ultimate success of miRNA therapeutics will depend on solving pharmacokinetic and targeted delivery issues. The development of a number of nanocarrier-based platforms holds significant promises to enhance the cell specific controlled delivery and safety profile of miRNA-based therapies. In this review, we provide among the most comprehensive assessments to date of promising nanomedicine platforms that have been tested preclinically, pertaining to the treatment of selected solid tumors including lung, liver, breast, and glioblastoma tumors as well as endocrine malignancies. The future challenges and potential applications in clinical oncology are discussed.

In vivo Engineering of Chromosome 19 q-arm by Employing the CRISPR/AsCpf1 and ddAsCpf1 Systems in Human Malignant Gliomas (Hypothesis)

Deletions of the q13.3 region of chromosome 19 have been found commonly in all three main kinds of diffuse human malignant gliomas, powerfully demonstrating the existence of tumor suppressor genes in this region. Consistent with the previous studies, the most common deletion interval has been mapped to a roughly 4 Mb region of 19q13.3 between the APOC2 and HRC genes, between genetic markers D19S219 and D19S246. EML2 is a tumor suppressor gene that is located on 19q13.32 and is considerably methylated in high-grade gliomas. Notably, MIR330 gene that is situated within the non-coding intronic region of EML2 is also detected as an oncosuppressor-miR in a variety of cancers including gliomas. Additionally, glioma oncoprotein Bcl2L12 which is located on 19q13.33 is significantly overexpressed in glioblastoma multiform and has a pivotal role in cancer evolution and resistance to apoptosis. Other genes such as MIR519D and NOP53 are also discovered as tumor suppressor genes in gliomas which are located on 19q13.3 and 19q13.4, respectively. Therefore, we hypothesize that a CRISPR/AsCpf1-based genome engineering strategy might be utilized to attach these deleted sizeable chromosomal portions of genes coding tumor suppressors as vital parts of the chromosome 19 q-arm with the purpose of treatment of this chromosomal abnormality in gliomas. Also, we can concurrently employ the CRISPR-ddAsCpf1 strategy for the precise suppression of Bcl2L12 oncogene in glioma.

pH and Reduction Dual-Responsive Bi-Drugs Conjugated Dextran Assemblies for Combination Chemotherapy and In Vitro Evaluation

Polymeric prodrugs, synthesized by conjugating chemotherapeutic agents to functional polymers, have been extensively investigated and employed for safer and more efficacious cancer therapy. By rational design, a pH and reduction dual-sensitive dextran-di-drugs conjugate (oDex-g-Pt+DOX) was synthesized by the covalent conjugation of Pt (IV) prodrug and doxorubicin (DOX) to an oxidized dextran (oDex). Pt (IV) prodrug and DOX were linked by the versatile efficient esterification reactions and Schiff base reaction, respectively. oDex-g-Pt+DOX could self-assemble into nanoparticles with an average diameter at around 180 nm. The acidic and reductive (GSH) environment induced degradation and drug release behavior of the resulting nanoparticles (oDex-g-Pt+DOX NPs) were systematically investigated by optical experiment, DLS analysis, TEM measurement, and in vitro drugs release experiment. Effective cellular uptake of the oDex-g-Pt+DOX NPs was identified by the human cervical carcinoma HeLa cells via confocal laser scanning microscopy. Furthermore, oDex-g-Pt+DOX NPs displayed a comparable antiproliferative activity than the simple combination of free cisplatin and DOX (Cis+DOX) as the extension of time. More importantly, oDex-g-Pt+DOX NPs exhibited remarkable reversal ability of tumor resistance compared to the cisplatin in cisplatin-resistant lung carcinoma A549 cells. Take advantage of the acidic and reductive microenvironment of tumors, this smart polymer-dual-drugs conjugate could serve as a promising and effective nanomedicine for combination chemotherapy.

Liposomal Delivery of MicroRNA-7 Targeting EGFR to Inhibit the Growth, Invasion, and Migration of Ovarian Cancer

Ovarian cancer is highly aggressive and has high rates of recurrence and metastasis. Due to the limited effects of current treatments, it is necessary to conduct research and develop new treatment options. The application of gene therapy in tumor therapy is gradually increasing and has exciting prospects. MicroRNA-7 (miR-7) has been reported to inhibit the growth, invasion, and metastasis of a variety of solid tumors. Cationic liposomes are safe and effective gene delivery systems for transfection in vivo and in vitro. To realize the application of miR-7 in the treatment of ovarian cancer, cationic liposomes were prepared with 1,2-dioleoyl-3-trimethylammonium-propane, 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine, and cholesterol. The miR-7 liposomes had a suitable particle size, potential, and a high cellular uptake rate. MiR-7 encapsulated by liposomes could be effectively delivered to ovarian cancer cells and successfully targeted to the tumor site in a mouse xenograft model of ovarian cancer. In vitro and in vivo experiments revealed that the miR-7 liposomes had a significant ability to inhibit the growth, invasion, and migration of ovarian cancer, probably by inhibiting the expression of the epidermal growth factor receptor. Our studies of miR-7 liposomes demonstrated a safe and efficient microRNA delivery system for the gene therapy of ovarian cancer.

Self-assembled and pH-responsive polymeric nanomicelles impart effective delivery of paclitaxel to cancer cells

Chemotherapy is an essential component of breast cancer therapy, but it is associated with serious side effects. Herein, a pluronic F68-based pH-responsive, and self-assembled nanomicelle system was designed to improve the delivery of paclitaxel (PTX) to breast cancer cells. Two pH-responsive pluronic F68-PTX conjugates i.e. succinoyl-linked conjugate (F68-SA-PTX) and cis-aconityl-linked conjugate (F68-CAA-PTX) were designed to respond the varying pH-environment in tumour tissue. Although both the linkers showed pH-sensitivity, the F68-CAA-PTX exhibited superior pH-sensitivity over the F68-SA-PTX and achieved a more selective release of PTX from the self-assembled nanomicelles. The prepared nanomicelles were characterized by dynamic light scattering, transmittance electron microscopy, differential scanning calorimetry and powder X-ray diffraction techniques. The anticancer activity of prepared nanomicelles and pure PTX were evaluated by 2D cytotoxicity assay against breast cancer cell line MDA-MB-231 and in the real tumour environments i.e. 3D tumor spheroids of MDA-MB-231 cells. The highest cytotoxicity effect of PTX was observed with F68-CAA-PTX nanomicelles followed by F68-SA-PTX and free PTX. Further, the F68-CAA-PTX nanomicelles also induced significant apoptosis with a combination of increase in ROS generation, decrease in the depolarisation of MMP and G2/M cell cycle arrest. These observed results provide a new insight for breast cancer treatment using pluronic nanomicelles.

Emerging nanotaxanes for cancer therapy

The clinical application of taxane (including paclitaxel, docetaxel, and cabazitaxel)-based formulations is significantly impeded by their off-target distribution, unsatisfactory release, and acquired resistance/metastasis. Recent decades have witnessed a dramatic progress in the development of high-efficiency, low-toxicity nanotaxanes via the use of novel biomaterials and nanoparticulate drug delivery systems (nano-DDSs). Thus, in this review, the achievements of nanotaxanes-targeted delivery and stimuli-responsive nano-DDSs-in preclinical or clinical trials have been outlined. Then, emerging nanotherapeutics against tumor resistance and metastasis have been overviewed, with a particular emphasis on synergistic therapy strategies (e.g., combination with surgery, chemotherapy, radiotherapy, biotherapy, immunotherapy, gas therapy, phototherapy, and multitherapy). Finally, the latest oral nanotaxanes have been briefly discussed.

Therapeutic Targeting of MicroRNAs in the Tumor Microenvironment

The tumor-microenvironment (TME) is an amalgamation of various factors derived from malignant cells and infiltrating host cells, including cells of the immune system. One of the important factors of the TME is microRNAs (miRs) that regulate target gene expression at a post transcriptional level. MiRs have been found to be dysregulated in tumor as well as in stromal cells and they emerged as important regulators of tumorigenesis. In fact, miRs regulate almost all hallmarks of cancer, thus making them attractive tools and targets for novel anti-tumoral treatment strategies. Tumor to stroma cell cross-propagation of miRs to regulate protumoral functions has been a salient feature of the TME. MiRs can either act as tumor suppressors or oncogenes (oncomiRs) and both miR mimics as well as miR inhibitors (antimiRs) have been used in preclinical trials to alter cancer and stromal cell phenotypes. Owing to their cascading ability to regulate upstream target genes and their chemical nature, which allows specific pharmacological targeting, miRs are attractive targets for anti-tumor therapy. In this review, we cover a recent update on our understanding of dysregulated miRs in the TME and provide an overview of how these miRs are involved in current cancer-therapeutic approaches from bench to bedside.

The Role of miRNA-7 in the Biology of Cancer and Modulation of Drug Resistance

MicroRNAs (miRNAs, miRs) are small non-coding RNA (ncRNA) molecules capable of regulating post-transcriptional gene expression. Imbalances in the miRNA network have been associated with the development of many pathological conditions and diseases, including cancer. Recently, miRNAs have also been linked to the phenomenon of multidrug resistance (MDR). MiR-7 is one of the extensively studied miRNAs and its role in cancer progression and MDR modulation has been highlighted. MiR-7 is engaged in multiple cellular pathways and acts as a tumor suppressor in the majority of human neoplasia. Its depletion limits the effectiveness of anti-cancer therapies, while its restoration sensitizes cells to the administered drugs. Therefore, miR-7 might be considered as a potential adjuvant agent, which can increase the efficiency of standard chemotherapeutics.

Non-coding RNAs and potential therapeutic targeting in cancer

Recent advances have begun to clarify the physiological and pathological roles of non-coding RNAs (ncRNAs) in various diseases, including cancer. Among these, microRNAs (miRNAs) have been the most studied and have emerged as key players that are involved in the regulation of important growth regulatory pathways in cancer pathogenesis. The ability of a single ncRNA to modulate the expression of multiple downstream gene targets and associated pathways, have provided a rationale to pursue them for therapeutic drug development in cancer. In this context, early data from pre-clinical studies have demonstrated that synthetic miRNA-based therapeutic molecules, along with various protective coating approaches, has allowed for their efficient delivery and anti-tumor activity. In fact, some of the miRNA-based cancer therapeutic strategies have shown promising results even in early-phase human clinical trials. While the enthusiasm for ncRNA-based cancer therapeutics continue to evolve, the field is still in the midst of unraveling a more precise understanding of the molecular mechanisms and specific downstream therapeutic targets of other lesser studied ncRNAs such as the long-non-coding RNAs, transfer RNAs, circular RNAs, small nucleolar RNAs, and piwi-interacting RNAs. This review article provides the current state of knowledge and the evolving principles for ncRNA-based therapeutic approaches in cancer, and specifically highlights the importance of data to date and the approaches that are being developed to overcome the challenges associated with their delivery and mitigating the off-target effects in human cancers.

Role of non-coding RNAs in modulating the response of cancer cells to paclitaxel treatment

Paclitaxel is a chemotherapeutic substance that is administered for treatment of an extensive spectrum of human malignancies. In spite of its potent short-term effects against tumor cells, resistance to paclitaxel occurs in a number of patients precluding its long-term application in these patients. Non-coding RNAs have been shown to influence response of cancer cells to this chemotherapeutic agent via different mechanisms. Mechanistically, these transcripts regulate expression of several genes particularly those being involved in the apoptotic processes. Lots of in vivo and in vitro assays have demonstrated the efficacy of oligonucleotide-mediated microRNAs (miRNA)/ long non-coding RNAs (lncRNA) silencing in enhancement of response of cancer cells to paclitaxel. Therefore, targeted therapies against non-coding RNAs have been suggested as applicable modalities for combatting resistance to this agent. In the present review, we provide a summary of studies which assessed the role of miRNAs and lncRNAs in conferring resistance to paclitaxel.

High-throughput sequencing identification of differentially expressed microRNAs in metastatic ovarian cancer with experimental validations

Background

Ovarian cancer (OC) is a common gynecological cancer and characterized by high metastatic potential. MicroRNAs (miRNAs, miRs) have the promise to be harnessed as prognostic and therapeutic biomarkers for OC. Herein, we sought to identify differentially expressed miRNAs and mRNAs in metastatic OC, and to validate them with functional experiments.

Methods

Differentially expressed miRNAs and mRNAs were screened from six pairs of primary OC tissues and metastatic tissues using a miRStar™ Human Cancer Focus miRNA and Target mRNA PCR Array. Then, gene expression profiling results were verified by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot assays. The binding affinity between miR-7-5p and TGFβ2 was validated by dual-luciferase reporter assay. Expression of miR-7-5p and TGFβ2 was manipulated to assess their roles in malignant phenotypes of highly metastatic HO-8910PM cells.

Results

MiRNA profiling and sequencing identified 12 miRNAs and 10 mRNAs that were differentially expressed in metastatic tissues. Gene ontology and Pathway analyses determined that 3 differentially expressed mRNAs (ITGB3, TGFβ2 and TNC) were related to OC metastasis. The results of RT-qPCR confirmed that the decrease of miR-7-5p was most significant in OC metastasis, while TGFβ2 was up-regulated in OC metastasis. Moreover, miR-7-5p targeted and negatively regulated TGFβ2. MiR-7-5p overexpression accelerated HO-8910PM cell viability and invasion, and TGFβ2 overexpression reversed the results. Meanwhile, simultaneous miR-7-5p and TGFβ2 overexpression rescued the cell activities.

Conclusions

This study characterizes differentially expressed miRNAs and mRNAs in metastatic OC, where miR-7-5p and its downstream target were most closely associated with metastatic OC. Overexpression of miR-7-5p targets and inhibits TGFβ2 expression, thereby inhibiting the growth and metastasis of OC.

High Levels of miR-7-5p Potentiate Crizotinib-Induced Cytokilling and Autophagic Flux by Targeting RAF1 in NPM-ALK Positive Lymphoma Cells

Simple Summary

Anaplastic lymphoma kinase positive anaplastic large cell lymphomas are a pediatric disease, which still needs treatment improvement. Crizotinib was the first ALK-targeted inhibitor used in clinics, but relapses are now known to occur. Current research efforts indicate that combined therapies could represent a superior strategy to eradicate malignant cells and prevent tumor recurrence. Autophagy is a self-digestion cellular process, known to be induced upon diverse cancer therapies. Our present work demonstrates that the potentiation of the crizotinib-induced autophagy flux, through the serine/threonine kinase RAF1 downregulation, drives ALK+ ALCL cells to death. These results should encourage further investigations on the therapeutic modulation of autophagy in this particular cancer settings and other ALK-related malignancies.

Abstract

Anaplastic lymphoma kinase positive anaplastic large cell lymphomas (ALK+ ALCL) are an aggressive pediatric disease. The therapeutic options comprise chemotherapy, which is efficient in approximately 70% of patients, and targeted therapies, such as crizotinib (an ALK tyrosine kinase inhibitor (TKI)), used in refractory/relapsed cases. Research efforts have also converged toward the development of combined therapies to improve treatment. In this context, we studied whether autophagy could be modulated to improve crizotinib therapy. Autophagy is a vesicular recycling pathway, known to be associated with either cell survival or cell death depending on the cancer and therapy. We previously demonstrated that crizotinib induced cytoprotective autophagy in ALK+ lymphoma cells and that its further intensification was associated with cell death. In line with these results, we show here that combined ALK and Rapidly Accelerated Fibrosarcoma 1 (RAF1) inhibition, using pharmacological (vemurafenib) or molecular (small interfering RNA targeting RAF1 (siRAF1) or microRNA-7-5p (miR-7-5p) mimics) strategies, also triggered autophagy and potentiated the toxicity of TKI. Mechanistically, we found that this combined therapy resulted in the decrease of the inhibitory phosphorylation on Unc-51-like kinase-1 (ULK1) (a key protein in autophagy initiation), which may account for the enforced autophagy and cytokilling effect. Altogether, our results support the development of ALK and RAF1 combined inhibition as a new therapeutic approach in ALK+ ALCL.

The Roles of ceRNAs-Mediated Autophagy in Cancer Chemoresistance and Metastasis

Simple Summary

Chemoresistance and metastasis are the main causes of treatment failure in cancers. Autophagy contribute to the survival and metastasis of cancer cells. Competing endogenous RNA (ceRNA), particularly long non-coding RNAs and circular RNA (circRNA), can bridge the interplay between autophagy and chemoresistance or metastasis in cancers via sponging miRNAs. This review aims to discuss on the function of ceRNA-mediated autophagy in the process of metastasis and chemoresistance in cancers. ceRNA network can sequester the targeted miRNA expression to indirectly upregulate the expression of autophagy-related genes, and thereof participate in autophagy-mediated chemoresistance and metastasis. Our clarification of the mechanism of autophagy regulation in metastasis and chemoresistance may greatly improve the efficacy of chemotherapy and survival in cancer patients. The combination of the tissue-specific miRNA delivery and selective autophagy inhibitors, such as hydroxychloroquine, is attractive to treat cancer patients in the future.

Abstract

Chemoresistance and metastasis are the main causes of treatment failure and unfavorable outcome in cancers. There is a pressing need to reveal their mechanisms and to discover novel therapy targets. Autophagy is composed of a cascade of steps controlled by different autophagy-related genes (ATGs). Accumulating evidence suggests that dysregulated autophagy contributes to chemoresistance and metastasis via competing endogenous RNA (ceRNA) networks including lncRNAs and circRNAs. ceRNAs sequester the targeted miRNA expression to indirectly upregulate ATGs expression, and thereof participate in autophagy-mediated chemoresistance and metastasis. Here, we attempt to summarize the roles of ceRNAs in cancer chemoresistance and metastasis through autophagy regulation.

Combinatory Treatment with miR-7-5p and Drug-Loaded Cubosomes Effectively Impairs Cancer Cells

BACKGROUND

Multidrug resistance (MDR) is an emerging problem in the treatment of cancer. Therefore, there is a necessity for novel strategies that would sensitize tumor cells to the administered chemotherapeutics. One of the innovative approaches in fighting drug-resistant tumors is the treatment of cancer with microRNA (miRNA), or the use of cubosomes (lipid nanoparticles) loaded with drugs. Here, we present a study on a novel approach, which combines both tools.

METHODS

Cubosomes loaded with miR-7-5p and chemotherapeutics were developed. The effects of drug- and miRNA-loaded vehicles on glioma- (A172, T98G), papillary thyroid- (TPC-1) and cervical carcinoma-derived (HeLa) cells were analyzed using molecular biology techniques, including quantitative real-time PCR, MTS-based cell proliferation test, flow cytometry and spheroids formation assay.

RESULTS

The obtained data indicate that miR-7-5p increases the sensitivity of the tested cells to the drug, and that nanoparticles loaded with both miRNA and the drug produce a greater anti-tumor effect in comparison to the free drug treatment. It was found that an increased level of apoptosis in the drug/miRNA co-treated cells is accompanied by an alternation in the expression of the genes encoding for key MDR proteins of the ABC family.

CONCLUSIONS

Overall, co-administration of miR-7-5p with a chemotherapeutic can be considered a promising strategy, leading to reduced MDR and the induction of apoptosis in cancer cells.

Syringic acid delivered via mPEG-PLGA-PLL nanoparticles enhances peripheral nerve regeneration effect

Aim: To deliver syringic acid (SA) with a nanocarrier and enhance its function. Materials & methods: mPEG-PLGA-PLL (PEAL) nanoparticles were used to deliver SA. The characterization, storage stability, drug release, blood-compatibility and biocompatibility of SA-PEAL were detected by in vitro and in vivo assays. Cellular phenotypic experiments and rat sciatic nerve injury models were used to evaluate the function of SA-PEALs. Results: SA-PEAL had good storage stability, blood-compatibility and biocompatibility and could slowly release SA. SA-PEAL significantly enhanced the proliferation and migration ability of Schwann cells and function recovery of injured sciatic nerves. Conclusion: Our study provides an effective nano-delivery system for enhancing the neural repair function of SA and promoting further applications of SA.

microRNAs as biomarkers of ovarian cancer

Introduction: Ovarian carcinoma (OC) is the leading cause of death in women with gynecologic cancers. Most patients are diagnosed at an advanced stage with a low five-year survival rate of 20-30%. Discovering novel biomarkers for early detection and outcome prediction of OC is an urgent medical need. miRNAs, a group of small non-coding RNAs, play critical roles in multiple biologic processes and cancer pathogenesis.Areas covered: We provide an in-depth look at the functions of miRNAs in OC, particularly focusing on their roles in chemoresistance and metastasis in OC. We also discuss the biological and clinical significance of miRNAs in exosomes and expand on long non-coding RNA which acts as ceRNA of miRNAs.Expert opinion: miRNAs participate in many biological processes including proliferation, apoptosis, chemoresistance, metastasis, epithelial-mesenchymal transition, and cancer stem cell. They will substantially contribute to our understanding of OC pathogenesis. Given their resistance to the degradation of ribonucleases and availability in plasma exosomes, miRNAs may serve as emerging biomarkers for cancer detection, therapeutic assessment, and prognostic prediction. Being a messenger, exosomal miRNAs are crucial for the crosstalk between cancer cells and stromal cells in tumor microenvironment.

MicroRNA-125a-Loaded Polymeric Nanoparticles Alleviate Systemic Lupus Erythematosus by Restoring Effector/Regulatory T Cells Balance

Systemic lupus erythematosus (SLE), a common lethal autoimmune disease, is characterized by effector/regulatory T cells imbalance. Current therapies are either inefficient or have severe side effects. MicroRNA-125a (miR-125a) can stabilize Treg-mediated self-tolerance by targeting effector programs, but it is significantly downregulated in peripheral T cells of patients with SLE. Therefore, overexpression of miR-125a may have therapeutic potential to treat SLE. Considering the stability and targeted delivery of miRNA remains a major challenge in vivo, we constructed a monomethoxy (polyethylene glycol)-poly(d,l-lactide-co-glycolide)-poly(l-lysine) (mPEG-PLGA-PLL) nanodelivery system to deliver miR-125a into splenic T cells. Results demonstrate that miR-125a-loaded mPEG-PLGA-PLL (PEAL_miR-125a) nanoparticles (NPs) exhibit good biocompatibility and protect miR-125a from degradation, thereby prolonging the circulatory time of miRNA in vivo. In addition, PEAL_miR-125a NPs are preferentially enriched in a pathological spleen and efficiently deliver miR-125a into the splenic T cells in SLE mice models. The PEAL_miR-125a NPs treatment significantly alleviates SLE disease progression by reversing the imbalance of effector/regulatory T cells. Collectively, the PEAL_miR-125a NPs show excellent therapeutic efficacy and safety, which may provide an effective treatment for SLE.

MicroRNA delivery through nanoparticles

MicroRNAs (miRNAs) are attracting a growing interest in the scientific community due to their central role in the etiology of major diseases. On the other hand, nanoparticle carriers offer unprecedented opportunities for cell specific controlled delivery of miRNAs for therapeutic purposes. This review critically discusses the use of nanoparticles for the delivery of miRNA-based therapeutics in the treatment of cancer and neurodegenerative disorders and for tissue regeneration. A fresh perspective is presented on the design and characterization of nanocarriers to accelerate translation from basic research to clinical application of miRNA-nanoparticles. Main challenges in the engineering of miRNA-loaded nanoparticles are discussed, and key application examples are highlighted to underline their therapeutic potential for effective and personalized medicine.

Dual functional immunostimulatory polymeric prodrug carrier with pendent indoximod for enhanced cancer immunochemotherapy

Immunotherapy based on checkpoint blockade has been regarded as one of the most promising approaches towards many types of cancers. However, low response rate hinders its application due to insufficient tumor immunogenicity and immunosuppressive tumor microenvironment. To achieve an overall enhanced therapeutic outcome, we developed a dual-functional immuno-stimulatory polymeric prodrug carrier modified with pendent indoximod, an indoleamine 2,3-dioxygenase (IDO) inhibitor that can be used to reverse immune suppression, for co-delivery of Doxorubicin (Dox), a hydrophobic anticancer agent that can promote immunogenic cell death (ICD) and elicit antitumor immunity. The resulted carrier denoted as POEG-b-PVBIND, consisting of poly (oligo (ethylene glycol) methacrylate) (POEG) hydrophilic blocks and indoximod conjugated hydrophobic blocks, is rationally designed to improve immunotherapy by synergistically modulating the tumor microenvironment (TME). Our data showed that Dox-triggered ICD promoted intra-tumoral infiltration of CD8+ T cells and IFN-γ-production by CD8+ T cells. Meanwhile, cleaved indoximod significantly increased CD8+ T cell infiltration while reducing the immunosuppressive T regulatory cells (Tregs). More importantly, Dox/POEG-b-PVBIND micelles led to significantly improved tumor regression in an orthotopic murine breast cancer model compared to both Dox-loaded POEG-b-PVB micelles (a control inert carrier) and POEG-b-PVBIND micelles alone, confirming combination effect of indoximod and Dox in improving the overall antitumor activity. STATEMENT OF SIGNIFICANCE: Indoleamine 2,3-dioxygenase (IDO) is an enzyme that can induce immune suppressive microenvironment in tumors. As a well-studied IDO inhibitor, indoximod (IND) represents a promising agent for cancer immunotherapy and could be particularly useful in combination with other chemotherapeutic agents. However, three major problems hinder its application: (1) IND is barely soluble in water; (2) IND delivery efficiency is limited (3) simultaneous delivery of two agents into tumor site is still challenging. Currently, most reports largely focus on improving the pharmacokinetic profile of IND alone via different formulations such as IND prodrug and IND nanocrystal. However, there is limited information about IND based co-delivery systems, especially for delivering hydrophobic chemotherapeutic agents. Here, we developed a new dual-functional polymeric prodrug carrier modified with a number of pendent IND units (denoted as POEG-b-PVBIND). POEG-b-PVBIND shows immunostimulatory and antitumor activities by itself. More importantly, POEG-b-PVBIND polymer is able to self-assemble into nano-sized micelles that are highly effective in formulating and codelivering other hydrophobic agents including doxorubicin (Dox), sunitinib (Sun), and daunorubicin (Dau), which can elicit antitumor immunity via promoting immunogenic cell death (ICD). We have shown that our new combination therapy led to a significantly improved antitumor activity in an aggressive murine breast cancer model (4T1.2).

Delivering Combination Chemotherapies and Targeting Oncogenic Pathways via Polymeric Drug Delivery Systems

The side-effects associated with chemotherapy necessitates better delivery of chemotherapeutics to the tumor. Nanoparticles can load higher amounts of drug and improve delivery to tumors, increasing the efficacy of treatment. Polymeric nanoparticles, in particular, have been used extensively for chemotherapeutic delivery. This review describes the efforts made to deliver combination chemotherapies and inhibit oncogenic pathways using polymeric drug delivery systems. Combinations of chemotherapeutics with other drugs or small interfering RNA (siRNA) combinations have been summarized. Special attention is given to the delivery of drug combinations that involve either paclitaxel or doxorubicin, two popular chemotherapeutics in clinic. Attempts to inhibit specific pathways for oncotherapy have also been described. These include inhibition of oncogenic pathways (including those involving HER2, EGFR, MAPK, PI3K/Akt, STAT3, and HIF-1α), augmentation of apoptosis by inhibiting anti-apoptosis proteins (Bcl-2, Bcl-xL, and survivin), and targeting dysregulated pathways such as Wnt/β-catenin and Hedgehog.

Polymeric Co-Delivery Systems in Cancer Treatment: An Overview on Component Drugs' Dosage Ratio Effect

Multiple factors are involved in the development of cancers and their effects on survival rate. Many are related to chemo-resistance of tumor cells. Thus, treatment with a single therapeutic agent is often inadequate for successful cancer therapy. Ideally, combination therapy inhibits tumor growth through multiple pathways by enhancing the performance of each individual therapy, often resulting in a synergistic effect. Polymeric nanoparticles prepared from block co-polymers have been a popular platform for co-delivery of combinations of drugs associated with the multiple functional compartments within such nanoparticles. Various polymeric nanoparticles have been applied to achieve enhanced therapeutic efficacy in cancer therapy. However, reported drug ratios used in such systems often vary widely. Thus, the same combination of drugs may result in very different therapeutic outcomes. In this review, we investigated polymeric co-delivery systems used in cancer treatment and the drug combinations used in these systems for synergistic anti-cancer effect. Development of polymeric co-delivery systems for a maximized therapeutic effect requires a deeper understanding of the optimal ratio among therapeutic agents and the natural heterogenicity of tumors.

Co-Delivery Nanosystems for Cancer Treatment: A Review

Massive data available on cancer therapy more than ever lead our mind to the general concept that there is no perfect treatment for cancer. Indeed, the biological complexity of this disease is too excessive to be treated by a single therapeutic approach. Current delivery systems containing a specific drug or gene have their particular opportunities and restrictions. It is worth noting that a considerable number of studies suggest that single- drug delivery systems result in insufficient suppression of cancer growth. Therefore, one of the main ideas of co-delivery system designing is to enhance the intended response or to achieve the synergistic/combined effect compared to the single drug strategy. This review focuses on various strategies for co-delivery of therapeutic agents in the treatment of cancer. The primary approaches within the script are categorized into co-delivery of conventional chemotherapeutics, gene-based molecules, and plant-derived materials. Each one is explained in examples with the recent researches. In the end, a brief summary is provided to conclude the gist of the review.

Circ-U2AF1 promotes human glioma via derepressing neuro-oncological ventral antigen 2 by sponging hsa-miR-7-5p

The prognosis for human glioma, a malignant tumor of the central nervous system, is poor due to its rapid growth, genetic heterogeneity, and inadequate understanding of its underlying molecular mechanisms. Circular RNAs composed of exonic sequences, represent an understudied form of noncoding RNAs (ncRNAs) that was discovered more than a decade ago, function as microRNA sponges. We aimed to assess the relationship between circ-U2AF1 (CircRNA ID: hsa_circ_0061868) and hsa-mir-7-5p and examine their effects on proliferation, apoptosis, and the metastatic phenotype of glioma cells regulated by neuro-oncological ventral antigen 2 (NOVA2). We found that the expression levels of circ-U2AF1 and NOVA2 were upregulated, while hsa-miR-7-5p was downregulated in human glioma tissues and glioma cell lines. Our data and bioinformatic analysis indicated the association of these molecules with glioma grade, a positive correlation between circ-U2AF1 and NOVA2 expression levels and a negative correlation of hsa-miR-7-5p with both circ-U2AF1 and NOVA2, respectively. In addition, silencing of circ-U2AF1 expression resulted in increased hsa-miR-7-5p expression and decreased NOVA2 expression both in vitro and in vivo. Luciferase assay confirmed hsa-miR-7-5p as a direct target of circ-U2AF1 and NOVA2 as a direct target of hsa-miR-7-5p. Functionally, silencing of circ-U2AF1 inhibits glioma development by repressing NOVA2 via upregulating hsa-miR-7-5p both in vitro and in vivo. Thus, we assumed that circ-U2AF1 promotes glioma malignancy via derepressing NOVA2 by sponging hsa-miR-7-5p. Taken together, we suggest that circ-U2AF1 can be a prognostic biomarker and the circ-U2AF1/hsa-miR-7-5p/NOVA2 regulatory pathway may be a novel therapeutic target for treating gliomas.

Recent Progress in Gene Therapy for Ovarian Cancer

Ovarian cancer is the most lethal gynecological malignancy in developed countries. This is due to the lack of specific symptoms that hinder early diagnosis and to the high relapse rate after treatment with radical surgery and chemotherapy. Hence, novel therapeutic modalities to improve clinical outcomes in ovarian malignancy are needed. Progress in gene therapy has allowed the development of several strategies against ovarian cancer. Most are focused on the design of improved vectors to enhance gene delivery on the one hand, and, on the other hand, on the development of new therapeutic tools based on the restoration or destruction of a deregulated gene, the use of suicide genes, genetic immunopotentiation, the inhibition of tumour angiogenesis, the alteration of pharmacological resistance, and oncolytic virotherapy. In the present manuscript, we review the recent advances made in gene therapy for ovarian cancer, highlighting the latest clinical trials experience, the current challenges and future perspectives.