Fatty Acid Synthase (FASN) siRNA-Encapsulated-Her-2 Targeted Fab'-Immunoliposomes for Gene Silencing in Breast Cancer Cells

Advances in liposome-based delivery of RNA therapeutics for cancer treatment

Liposomal drug delivery systems stand as versatile therapeutic platforms for precisely targeting related elements in cancerous tissues owing to their intrinsic passive and acquired active targeting capabilities and exceptional compatibility with physiologic environments. When the capacity of liposomes as nanocarriers is combined with the revolutionary potential of RNA therapies in affecting undruggable targets, the outcome would be promising drug candidates as game-changers in the cancer treatment arena. However, optimizing liposome composition, physicochemical properties, and surface chemistry is paramount to maximizing their pharmacokinetic and pharmacodynamic attributes. This review highlighted the potential of liposomes as nanovehicles for RNA therapeutics through a literature review and looked at the most recent preclinical and clinical advancements in utilizing liposomal RNA therapeutics for cancer management. Notably, the discovery of novel targets, advancements in liposome engineering, and organizing well-planned clinical trials would help uncover the incredible potential of these nanotherapeutics in cancer patients.

HER-2-Targeted Boron Neutron Capture Therapy with Carborane-integrated Immunoliposomes Prepared via an Exchanging Reaction

Boron neutron capture therapy (BNCT) is a promising modality for cancer treatment because of its minimal invasiveness. To maximize the therapeutic benefits of BNCT, the development of efficient platforms for the delivery of boron agents is indispensable. Here, carborane-integrated immunoliposomes were prepared via an exchanging reaction to achieve HER-2-targeted BNCT. The conjugation of an anti-HER-2 antibody to carborane-integrated liposomes successfully endowed these liposomes with targeting properties toward HER-2-overexpressing human ovarian cancer cells (SK-OV3); the resulting BNCT activity toward SK-OV3 cells obtained using the current immunoliposomal system was 14-fold that of the l-BPA/fructose complex, which is a clinically available boron agent. Moreover, the growth of spheroids treated with this system followed by thermal neutron irradiation was significantly suppressed compared with treatment with the l-BPA/fructose complex.

Dissolving microneedles-based programmed delivery system for enhanced chemo-immunotherapy of melanoma

Immune checkpoint blockade, especially the programmed cell death ligand 1 (PD-L1) blockade, has revolutionized the treatment of melanoma. However, PD-1/PD-L1 monotherapy leads to unsatisfactory therapeutic outcomes. The immunotherapy of melanoma could be improved by adding doxorubicin (DOX), which triggers immunogenic cell death (ICD) effect to activate anti-tumor immunity. Additionally, microneedles, especially dissolving microneedles (dMNs), can further enhance outcomes of chemo-immunotherapy due to the physical adjuvant effect of dMNs. Herein, we developed the dMNs-based programmed delivery system that incorporated pH-sensitive and melanoma-targeting liposomes to co-deliver DOX and siPD-L1, achieving enhanced chemo-immunotherapy of melanoma (si/DOX@LRGD dMNs). The incorporated si/DOX@LRGD LPs demonstrated uniform particle size, pH-sensitive drug release, high in vitro cytotoxicity and targeting ability. Besides, si/DOX@LRGD LPs effectively downregulated the expression of PD-L1, induced tumor cell apoptosis and triggered ICD effect. The si/DOX@LRGD LPs also showed deep penetration (approximately 80 μm) in 3D tumor spheroids. Moreover, si/DOX@LRGD dMNs dissolved rapidly into the skin and had sufficient mechanical strength to penetrate skin, reaching a depth of approximately 260 μm in mice skin. In mice model of melanoma tumor, si/DOX@LRGD dMNs exhibited better anti-tumor efficacy than monotherapy by dMNs and tail intravenous injection at the same dose. This was due to the higher cytotoxic CD8+ T cells and the secreted cytotoxic cytokine IFN-γ evoked by si/DOX@LRGD dMNs, thereby eliciting strong T-cell mediated immune response and resulted in enhanced anti-tumor effects. In conclusion, these findings suggested that si/DOX@LRGD dMNs provided a promising and effective strategy for enhanced chemo-immunotherapy of melanoma.

Nanotechnology-enabled gene delivery for cancer and other genetic diseases

INTRODUCTION

Despite gene therapy is ideal for genetic abnormality-related diseases, the easy degradation, poor targeting, and inefficiency in entering targeted cells are plaguing the effective delivery of gene therapy. Viral and non-viral vectors have been used for delivering gene therapeutics in vivo by safeguarding nucleic acid agents to target cells and to reach the specific intracellular location. A variety of nanotechnology-enabled safe and efficient systems have been successfully developed to improve the targeting ability for effective therapeutic delivery of genetic drugs.

AREAS COVERED

In this review, we outline the multiple biological barriers associated with gene delivery process, and highlight recent advances to gene therapy strategy in vivo, including gene correction, gene silencing, gene activation and genome editing. We point out current developments and challenges exist of non-viral and viral vector systems in association with chemical and physical gene delivery technologies and their potential for the future.

EXPERT OPINION

This review focuses on the opportunities and challenges to various gene therapy strategy, with specific emphasis on overcoming the challenges through the development of biocompatibility and smart gene vectors for potential clinical application.

pH and its applications in targeted drug delivery

Physiologic pH is vital for the normal functioning of tissues and varies in different parts of the body. The varying pH of the body has been exploited to design pH-sensitive smart oral, transdermal and vaginal drug delivery systems (DDS). The DDS demonstrated promising results in hard-to-treat diseases such as cancer and Helicobacter pylori infection. In some cases, a change in pH of tissues or body fluids has also been employed as a useful diagnostic biomarker. This paper aims to comprehensively review the development and applications of pH-sensitive DDS as well as recent advances in the field.

siRNA and targeted delivery systems in breast cancer therapy

Recently, nucleic acid drugs have been considered as promising candidates in treatment of various diseases, especially cancer. Because of developing resistance to conventional chemotherapy, use of genetic tools in cancer therapy appears inevitable. siRNA is a RNAi tool with capacity of suppressing target gene. Owing to overexpression of oncogenic factors in cancer, siRNA can be used for suppressing those pathways. This review emphasizes the function of siRNA in treatment of breast tumor. The anti-apoptotic-related genes including Bcl-2, Bcl-xL and survivin can be down-regulated by siRNA in triggering cell death in breast cancer. STAT3, STAT8, Notch1, E2F3 and NF-κB are among the factors with overexpression in breast cancer that their silencing by siRNA paves the way for impairing tumor proliferation and invasion. The oncogenic mechanisms in drug resistance development in breast tumor such as lncRNAs can be suppressed by siRNA. Furthermore, siRNA reducing P-gp activity can increase drug internalization in tumor cells. Because of siRNA degradation at bloodstream and low accumulation at tumor site, nanoplatforms have been employed for siRNA delivery to suppress breast tumor progression via improving siRNA efficacy in gene silencing. Development of biocompatible and efficient nanostructures for siRNA delivery can make milestone progress in alleviation of breast cancer patients.

Aptamer-siRNA chimeras: Promising tools for targeting HER2 signaling in cancer

RNA interference is a transformative approach and has great potential in the development of novel and more efficient cancer therapeutics. Immense prospects exist in the silencing of HER2 and its downstream genes which are overexpressed in many cancers, through exogenously delivered siRNA. However, there is still a long way to exploit the full potential and versatility of siRNA therapeutics due to the challenges associated with the stability and delivery of siRNA targeted to specific sites. Aptamers offer several advantages as a vehicle for siRNA delivery, over other carriers such as antibodies. In this review, we discuss the progress made in the development and applications of aptamer-siRNA chimeras in HER2 targeting and gene silencing. A schematic workflow is also provided which will provide ample insight for all those researchers who are new to this field. Also, we think that a mechanistic understanding of the HER2 signaling pathway is crucial in designing extensive investigations aimed at the silencing of a wider array of genes. This review is expected to stimulate more research on aptamer-siRNA chimeras targeted against HER2 which might arm us with potential effective therapeutic interventions for the management of cancer.

Antibody-Incorporated Nanomedicines for Cancer Therapy

Antibody-based cancer therapy, one of the most significant therapeutic strategies, has achieved considerable success and progress over the past decades. Nevertheless, obstacles including limited tumor penetration, short circulation half-lives, undesired immunogenicity, and off-target side effects remain to be overcome for the antibody-based cancer treatment. Owing to the rapid development of nanotechnology, antibody-containing nanomedicines that have been extensively explored to overcome these obstacles have already demonstrated enhanced anticancer efficacy and clinical translation potential. This review intends to offer an overview of the advancements of antibody-incorporated nanoparticulate systems in cancer treatment, together with the nontrivial challenges faced by these next-generation nanomedicines. Diverse strategies of antibody immobilization, formats of antibodies, types of cancer-associated antigens, and anticancer mechanisms of antibody-containing nanomedicines are provided and discussed in this review, with an emphasis on the latest applications. The current limitations and future research directions on antibody-containing nanomedicines are also discussed from different perspectives to provide new insights into the construction of anticancer nanomedicines.

Experimental and Theoretical Insights on Chemopreventive Effect of the Liposomal Thymoquinone Against Benzo[a]pyrene-Induced Lung Cancer in Swiss Albino Mice

Purpose

Thymoquinone (TQ), a phytoconstituent of Nigella sativa seeds, has been studied extensively in various cancer models. However, TQ’s limited water solubility restricts its therapeutic applicability. Our work aims to prepare the novel formulation of TQ and assess its chemopreventive potential in chemically induced lung cancer animal model.

Methods

The polyethylene glycol coated DOPE/CHEMS incorporating TQ-loaded pH-sensitive liposomes (TQPSL) were prepared and characterized. Mice were exposed to benzo[a]pyrene (BaP) thrice a week for 4 weeks to induce lung cancer. TQPSL was administered three times a week for 21 weeks, starting 2 weeks before the first dose of BaP.

Results

The prepared TQPSL revealed 85% entrapment efficiency with 128 nm size and −19.5 mv ζ-potential showing high stability of the formulation. The pretreatment of TQPSL showed the recovery in BaP-modulated relative organ weight of lungs, cancer marker enzymes, and antioxidant enzymes in the serum. The histopathological analysis of the tissues showed that TQPSL protected the malignancy in the lungs. The flow cytometry data revealed the induction of apoptosis and decreased intracellular ROS by TQPSL. Molecular docking was performed to predict the TQ’s affinity for eight possible anticancer drug targets linked to lung cancer etiology. The data assisted to identify the serine/threonine-protein kinase BRAF as the most suitable target of TQ with binding energy −6.8 kcal/mol.

Conclusion

The current findings demonstrated the potential of TQPSL and its possible therapeutic targets of lung cancer. To our knowledge, this is the first research to outline the development of TQ formulation against lung cancer considering its low solubility as well as pulmonary delivery challenges.

Her-2 directed systemic delivery of fatty acid synthase (FASN) siRNA with novel liposomal carrier systems in the breast cancer mouse model

Despite the current advancements in the gene silencing therapy in vitro, the systemic delivery of siRNA still remains a challenging task for its transition into clinics. We have previously developed the Her2-targeted fatty acid synthase (FASN) siRNA-encapsulating immunoliposomes (ILs) with a great stability in the presence of serum. We report here the therapeutic potential of the lipid-based novel formulations in the breast cancer mouse model. The growth inhibitory and gene silencing effects of various formulations were determined by measuring the size of the tumor, cell proliferation, apoptotic index and immunoassays against Her2-over expressed tumor xenografts in nude mice. The pegylated DSPC/Chol and DOPE/CHEMS immunoliposomes containing FASN-siRNA significantly decreased the tumor growth relative to non-targeted liposomes. They induced the 1.5-fold increase in cellular apoptosis and several fold decrease in proliferation as compared to non-targeted liposomal formulations of FASN-siRNA. Moreover, FASN-siRNA-ILs produced several fold increase in the ratios of p53/p21 and Bax/Bcl-2. The gene silencing effects of targeted FASN-liposomes were found significantly superior, resulting in 30%-40% downregulation in FASN as compared to non-targeted similar formulations. Both types of FASN immunoliposomes provided a highly efficient approach for targeted delivery in Her-2-expressed breast cancer and thus offered a promising anticancer strategy in the clinical therapy.

The Effect of Liposomal Diallyl Disulfide and Oxaliplatin on Proliferation of Colorectal Cancer Cells: In Vitro and In Silico Analysis

Diallyl disulfide (DADS) is one of the main bioactive organosulfur compounds of garlic, and its potential against various cancer models has been demonstrated. The poor solubility of DADS in aqueous solutions limits its uses in clinical application. The present study aimed to develop a novel formulation of DADS to increase its bioavailability and therapeutic potential and evaluate its role in combination with oxaliplatin (OXA) in the colorectal cancer system. We prepared and characterized PEGylated, DADS (DCPDD), and OXA (DCPDO) liposomes. The anticancer potential of these formulations was then evaluated in HCT116 and RKO colon cancer cells by different cellular assays. Further, a molecular docking-based computational analysis was conducted to determine the probable binding interactions of DADS and OXA. The results revealed the size of the DCPDD and DCPDO to be 114.46 nm (95% EE) and 149.45 nm (54% EE), respectively. They increased the sensitivity of the cells and reduced the IC₅₀ several folds, while the combinations of them showed a synergistic effect and induced apoptosis by 55% in the cells. The molecular docking data projected several possible targets of DADS and OXA that could be evaluated more precisely by these novel formulations in detail. This study will direct the usage of DCPDD to augment the therapeutic potential of DCPDO against colon cancer in clinical settings.

Safety, Stability, and Therapeutic Efficacy of Long-Circulating TQ-Incorporated Liposomes: Implication in the Treatment of Lung Cancer

Thymoquinone (TQ), which is one of the main bioactive constituents of Nigella sativa seeds, has demonstrated its potential against various cancer models. The poor solubility of TQ in aqueous solution limits its uses in clinical application. The present study aimed to develop a novel formulation of TQ to increase its bioavailability and therapeutic potential with minimal toxicity. Polyethylene glycol (PEG)-coated DSPC/cholesterol comprising TQ liposomes (PEG-Lip-TQ) were prepared and characterized on various aspects. A computational investigation using molecular docking was used to assess the possible binding interactions of TQ with 12 prospective anticancer drug targets. The in vitro anticancer activity was assessed in A549 and H460 lung cancer cells in a time- and dose-dependent manner, while the oral acute toxicity assay was evaluated in silico as well as in vivo in mice. TQ docked to the Hsp90 target had the lowest binding energy of −6.05 kcal/mol, whereas caspase 3 was recognized as the least likely target for TQ with a binding energy of −1.19 kcal/mol. The results showed 96% EE with 120 nm size, and −10.85 mv, ζ-potential of PEG-Lip-TQ, respectively. The cell cytotoxicity data demonstrated high sensitivity of PEG-Lip-TQ and a several fold decrease in the IC₅₀ while comparing free TQ. The cell cycle analysis showed changes in the distribution of cells with doses. The in vivo data revealed an ~9-fold increase in the LD₅₀ of PEG-Lip-TQ on free TQ as an estimated 775 and 89.5 mg/kg b.w, respectively. This study indicates that the pharmacological and efficacy profile of PEG-lip-TQ is superior to free TQ, which will pave the way for an exploration of the effect of TQ formulation in the treatment of lung cancer in clinical settings.

Landscape of the oncogenic role of fatty acid synthase in human tumors

Background: Identifying a unique and common regulatory pathway that drives tumorigenesis in cancers is crucial to foster the development of effective treatments. However, a systematic analysis of fatty acid synthase across pan-cancers has not been carried out.

Methods: We investigated the oncogenic roles of fatty acid synthase in 33 cancers based on the cancer genome atlas and gene expression omnibus.

Results: Fatty acid synthase is profoundly expressed in most cancers and is an important factor in predicting the outcome of cancer patients. Further, the level of S207 phosphorylation was found to be improved in several neoplasms (e.g., colon cancer). Fatty acid synthase expression is related to tumor-infiltrating immune cells in tumors (e.g., CD8+ T-cell infiltration level in cervical squamous cell carcinoma). Moreover, hormone receptor binding- and fatty acid metabolic process-associated pathways are involved in the functional mechanisms of fatty acid synthase.

Conclusions: This study provides a complete understanding of the oncogenic role of fatty acid synthase in human tumors.

Acidic tumor microenvironment-sensitive liposomes enhance colorectal cancer therapy by acting on both tumor cells and cancer-associated fibroblasts

Cancer-associated fibroblasts (CAFs) play a crucial role in facilitating tumor invasion and metastasis, which act as the "soil" in the tumor microenvironment (TME). Accordingly, it would be a promising strategy to enhance the antitumor effect by killing both tumor cells and CAFs simultaneously. Herein, novel TME acid-responsive liposomes for co-delivery of IRI and 398 (IRI&398-s-LPs) were developed, in which the rapid release of both drugs could be triggered under acidic conditions. Notably, a CT-26/3T3 cell co-culture system was used to mimic the real TME both in vitro and in vivo. Cellular immunofluorescence revealed that IRI&398-s-LPs could efficiently decrease the activation of CAFs. In vitro cytotoxicity evaluation demonstrated that IRI&398-s-LPs exhibited higher cytotoxicity than the other liposomal formulations in the CT-26 and CT-26/3T3 cell co-culture system. In vivo NIRF imaging showed that the IRI&398-s-LPs could increase drug accumulation in the tumor sites. Furthermore, IRI&398-s-LPs not only presented superior in vivo anti-tumor activity in CT-26 bearing BALB/c mice, but also enhanced the effect in CT-26/3T3 cell bearing mice with decreased collagen and CAF biomarker expression. Furthermore, IRI&398-s-LPs also presented superior anti-metastatic efficiency in a lung metastasis model. These results indicated that this combinational strategy for eliminating both tumor cells and CAFs provides a new approach for cancer therapy, and the prepared TME-responsive liposomes for co-delivery of drugs hold promising clinical application prospects.

Liposomal Ellagic Acid Alleviates Cyclophosphamide-Induced Toxicity and Eliminates the Systemic Cryptococcus neoformans Infection in Leukopenic Mice

Cryptococcus neoformans infections rose sharply due to rapid increase in the numbers of immunocompromised individuals in recent years. Treatment of Cryptococcosis in immunocompromised persons is largely very challenging and hopeless. Hence, this study aimed to determine the activity of ellagic acid (EA) in the treatment of C. neoformans in cyclophosphamide injected leukopenic mice. A liposomal formulation of ellagic acid (Lip-EA) was prepared and characterized, and its antifungal activity was assessed in comparison to fluconazole (FLZ). The efficacy of the drug treatment was tested by assessing survival rate, fungal burden, and histological analysis in lung tissues. The safety of the drug formulations was tested by investigating hepatic, renal function, and antioxidant levels. The results of the present work demonstrated that Lip-EA, not FLZ, effectively eliminated C. neoformans infection in the leukopenic mice. Mice treated with Lip-EA (40 mg/kg) showed 70% survival rate and highly reduced fungal burden in their lung tissues, whereas the mice treated with FLZ (40 mg/kg) had 20% survival rate and greater fungal load in their lungs. Noteworthy, Lip-EA treatment alleviated cyclophosphamide-induced toxicity and restored hepatic and renal function parameters. Moreover, Lip-EA treatment restored the levels of superoxide dismutase and reduced glutathione and catalase in the lung tissues. The effect of FLZ or EA or Lip-EA against C. neoformans infection was assessed by the histological analysis of lung tissues. Lip-EA effectively reduced influx of inflammatory cells, thickening of alveolar walls, congestion, and hemorrhage. The findings of the present study suggest that Lip-EA may prove to be a promising therapeutic formulation against C. neoformans in immunocompromised persons.

Antioxidant Resveratrol Increases Lipolytic and Reduces Lipogenic Gene Expression under In Vitro Heat Stress Conditions in Dedifferentiated Adipocyte-Derived Progeny Cells from Dairy Cows

Heat stress (HS) induces oxidative stress by increasing reactive oxygen species (ROS), and the polyphenol resveratrol (RSV) has been shown to have antioxidant properties by reducing ROS. Hence, we aimed to examine the effects of RSV, HS and their interaction on bovine adipocytes. We generated bovine dedifferentiated adipocyte-derived progeny (DFAT) cells from subcutaneous adipose tissue and examined the effects of RSV (100 µM), heat conditions: isothermal (ISO-37 °C), short heat (SH-41.2 °C for 1 h) and long HS (LH-41.2 °C for 16 h), and their interaction on gene expression in DFAT-cells. In medium of DFAT-cells treated with RSV, malondialdehyde levels were reduced and oxygen-radical absorbance-capacity levels were increased compared to control. Treating DFAT-cells with RSV increased the relative mRNA expression of stress-induced-phosphoprotein-1 (STIP1) and the expression of hormone-sensitive-lipase (LIPE) and perilipin-1 (PLIN1), whereas it reduced the expressions of fatty-acid-synthase (FASN) and of pro-inflammatory chemotactic-C-C-motif-chemokine-ligand-2 (CCL2) also under HS. Moreover, reduced protein abundance of FASN was found in RSV-treated DFAT-cells compared to controls. Molecular docking of RSV with FASN confirmed its possible binding to FASN active site. This work demonstrates that RSV has an antioxidant effect on bovine DFAT cells and may induce adipose lipolysis and reduce lipogenesis also under in vitro HS conditions.