Antibody fragment-conjugated gemcitabine and paclitaxel-based liposome for effective therapeutic efficacy in pancreatic cancer

Solid lipid nanoparticles in pancreatic cancer treatment

Pancreatic cancer comes with one of the poorest prognoses of all cancers and as such it is crucial that new therapies are developed to improve on the current statistics. Currently, chemotherapy is the cornerstone of pancreatic cancer treatment with several drugs, and combinations of drugs being utilised for their anti-cancer effect. However, pancreatic cancer has a dense stroma around the tumour and intratumoral bacteria which result in drugs having difficulty penetrating the tumour or being metabolised by bacteria rendering them inactive. The utilisation of nanotechnology in chemotherapy for pancreatic cancer has been a huge area of focus for researchers worldwide with most of the focus being on lipid-based, inorganic and polymer-based nanoparticles. Solid lipid nanoparticles which have been studied since being first published in the 1990s, have been poorly researched for pancreatic cancer applications. Being composed of physiological lipids, solid lipid nanoparticles offer a greatly reduced risk of acute or chronic toxicities arising compared to inorganic or polymeric nanoparticles. They also possess the ability to improve on circulation time, permeability, and bioavailability of many first-line chemotherapeutics.

Recent advances in functional lipid-based nanomedicines as drug carriers for organ-specific delivery

Lipid-based nanoparticles have emerged as promising drug delivery systems for a wide range of therapeutic agents, including plasmids, mRNA, and proteins. However, these nanoparticles still encounter various challenges in drug delivery, including drug leakage, poor solubility, and inadequate target specificity. In this comprehensive review, we present an in-depth investigation of four distinct drug delivery methods: liposomes, lipid nanoparticle formulations, solid lipid nanoparticles, and nanoemulsions. Moreover, we explore recent advances in lipid-based nanomedicines (LBNs) for organ-specific delivery, employing ligand-functionalized particles that specifically target receptors in desired organs. Through this strategy, LBNs enable direct and efficient drug delivery to the intended organs, leading to superior DNA or mRNA expression outcomes compared to conventional approaches. Importantly, the development of novel ligands and their judicious combination holds promise for minimizing the side effects associated with nonspecific drug delivery. By leveraging the unique properties of lipid-based nanoparticles and optimizing their design, researchers can overcome the limitations associated with current drug delivery systems. In this review, we aim to provide valuable insights into the advancements, challenges, and future directions of lipid-based nanoparticles in the field of drug delivery, paving the way for enhanced therapeutic strategies with improved efficacy and reduced adverse effects.

Metformin-encapsulating immunoliposomes conjugated with anti-TROP 2 antibody fragments for the active targeting of triple-negative breast cancer

Trophoblast cell-surface antigen 2 (TROP 2) has re-emerged as a promising biomarker in triple-negative breast cancer (TNBC), with high overexpression in many TNBC cases. However, despite its potential and approval as an antibody-drug-conjugate for TNBC treatment, TROP 2-targeted delivery systems are currently underexplored. Therefore, this study was aimed at exploiting the potential of TROP 2 targeting by encapsulating metformin (Met), an antidiabetic drug associated with tumor growth inhibitory properties, inside liposomes decorated with TROP 2-targeting single-chain variable fragments (scFvs). The optimization of scFv grafting resulted in Met-immunoliposomes with an average diameter of less than 200 nm, low polydispersity index (∼0.1), negative surface charge (<-10 mV), high Met drug loading (>150 mg g-1), and high affinity towards TROP 2 binding. Furthermore, Met-immunoliposomes were reproducible, and the scFv conjugation was stable in the presence of serum for five days. Their cellular uptake increased 4 folds in two-dimensional and 9 folds in three-dimensional TNBC models owing to the high affinity towards TROP 2 binding. Finally, it was observed that the therapeutic effect of Met in suppressing cancer cell growth and proliferation was superior when using anti-TROP 2 scFv-grafted Met-immunoliposomes, which completely stopped the spheroid growth and inhibited the expression of adenosine triphosphate. This study is one of the first reports to explore the combination of nanoparticle-based drug delivery systems to target the TROP 2 protein in TNBC, and to the best of our knowledge, this is the first report to specifically combine the use of scFvs with TROP 2 targeting to deliver therapeutics for TNBC treatment.

Recent Developments in Nanotechnology and Immunotherapy for the Diagnosis and Treatment of Pancreatic Cancer

Pancreatic cancer kills millions of people worldwide each year and is one of the most prevalent causes of mortality that requires prompt therapy. A large number of people suffering from pancreatic cancer are detected at an advanced stage, with incurable and drug-resistant tumor, hence the overall survival rate of pancreatic cancer is less. The advance phase of this cancer is generated because of expression of the cancer-causing gene, inactivation of the tumorsuppressing gene, and deregulation of molecules in different cellular signalling pathways. The prompt diagnosis through the biomarkers significantly evades the progress and accelerates the survival rates. The overexpression of Mesothelin, Urokinase plasminogen activator, IGFR, Epidermal growth factor receptor, Plectin-1, Mucin-1 and Zinc transporter 4 were recognized in the diagnosis of pancreatic cancer. Nanotechnology has led to the development of nanocarriersbased formulations (lipid, polymer, inorganic, carbon based and advanced nanocarriers) which overcome the hurdles of conventional therapy, chemotherapy and radiotherapy which causes toxicity to adjacent healthy tissues. The biocompatibility, toxicity and large-scale manufacturing are the hurdles associated with the nanocarriers-based approaches. Currently, Immunotherapybased techniques emerged as an efficient therapeutic alternative for the prevention of cancer. Immunological checkpoint targeting techniques have demonstrated significant efficacy in human cancers. Recent advancements in checkpoint inhibitors, adoptive T cell therapies, and cancer vaccines have shown potential in overcoming the immune evasion mechanisms of pancreatic cancer cells. Combining these immunotherapeutic approaches with nanocarriers holds great promise in enhancing the antitumor response and improving patient survival.

Dual drug-loaded tumor-targeted polymeric nanoparticles for enhancing therapeutic response in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease where standard-of-care chemotherapeutic drugs have limited efficacy due to the development of drug resistance and poor drug delivery caused by a highly desmoplastic tumor microenvironment. Combining multiple drugs in a tumor-targeting carrier would be a favorable approach to overcome these limitations. Hence, a tumor-targeted peptide (TTP) conjugated amphiphilic tri-block copolymer was developed to make targeted polymer nanoparticles (TTP-PNPs) serving as a vehicle for carrying gemcitabine (Gem), paclitaxel (PTX), and their combination (Gem + PTX). The TTP-PNPs in the form of empty polymer (P), single drug-loaded [P(Gem) and P(PTX)], and dual drug-loaded [P(Gem + PTX)] polymer nanoformulations exhibited stable and homogenous spherical shapes with 110-160 nm size. These nanoformulations demonstrated excellent stability under in vitro physiological conditions and led to an efficient release of the drugs in the presence of reduced glutathione (GSH). The efficacy of these nanoparticles was thoroughly evaluated in vitro and in vivo, demonstrating a notable capacity to selectively target and restrict PDAC cells (PANC-1 and KPC) growth. The cellular uptake and biodistribution study showed a significantly higher tumor-targeting ability of TTP-PNPs than PNPs without TTP. Notably, P(Gem + PTX) exhibited the lowest IC50 compared to all other controls and showed heightened synergistic effects in both cell lines. Furthermore, P(Gem + PTX) showed a significantly better tumor reduction and median overall survival in mouse models than single drug-loaded TTP-PNPs or a combination of free drugs (Gem + PTX). In summary, our TTP-PNP system shows great promise as a novel platform for delivering Gem + PTX specifically to pancreatic cancer (PC), maximizing the therapeutic benefits with lower concentrations of the drugs and potentially reducing toxic side effects.

Analytical Techniques for Characterizing Tumor-Targeted Antibody-Functionalized Nanoparticles

The specific interaction between cell surface receptors and corresponding antibodies has driven opportunities for developing targeted cancer therapies using nanoparticle systems. It is challenging to design and develop such targeted nanomedicines using antibody ligands, as the final nanoconjugate's specificity hinges on the cohesive functioning of its components. The multicomponent nature of antibody-conjugated nanoparticles also complicates the characterization process. Regardless of the type of nanoparticle, it is essential to perform physicochemical characterization to establish a solid foundation of knowledge and develop suitable preclinical studies. A meaningful physicochemical evaluation of antibody-conjugated nanoparticles should include determining the quantity and orientation of the antibodies, confirming the antibodies' integrity following attachment, and assessing the immunoreactivity of the obtained nanoconjugates. In this review, the authors describe the various techniques (electrophoresis, spectroscopy, colorimetric assays, immunoassays, etc.) used to analyze the physicochemical properties of nanoparticles functionalized with antibodies and discuss the main results.

Site-specific delivery of cisplatin and paclitaxel mediated by liposomes: A promising approach in cancer chemotherapy

The site-specific delivery of drugs, especially anti-cancer drugs has been an interesting field for researchers and the reason is low accumulation of cytotoxic drugs in cancer cells. Although combination cancer therapy has been beneficial in providing cancer drug sensitivity, targeted delivery of drugs appears to be more efficient. One of the safe, biocompatible and efficient nano-scale delivery systems in anti-cancer drug delivery is liposomes. Their particle size is small and they have other properties such as adjustable physico-chemical properties, ease of functionalization and high entrapment efficiency. Cisplatin is a chemotherapy drug with clinical approval in patients, but its accumulation in cancer cells is low due to lack of targeted delivery and repeated administration results in resistance development. Gene and drug co-administration along with cisplatin/paclitaxel have resulted in increased sensitivity in tumor cells, but there is still space for more progress in cancer therapy. The delivery of cisplatin/paclitaxel by liposomes increases accumulation of drug in tumor cells and impairs activity of efflux pumps in promoting cytotoxicity. Moreover, phototherapy along with cisplatin/paclitaxel delivery can increase potential in tumor suppression. Smart nanoparticles including pH-sensitive nanoparticles provide site-specific delivery of cisplatin/paclitaxel. The functionalization of liposomes can be performed by ligands to increase targetability towards tumor cells in mediating site-specific delivery of cisplatin/paclitaxel. Finally, liposomes can mediate co-delivery of cisplatin/paclitaxel with drugs or genes in potentiating tumor suppression. Since drug resistance has caused therapy failure in cancer patients, and cisplatin/paclitaxel are among popular chemotherapy drugs, delivery of these drugs mediates targeted suppression of cancers and prevents development of drug resistance. Because of biocompatibility and safety of liposomes, they are currently used in clinical trials for treatment of cancer patients. In future, the optimal dose of using liposomes and optimal concentration of loading cisplatin/paclitaxel on liposomal nanocarriers in clinical trials should be determined.

Anti-CD4 antibody and dendrimeric peptide based targeted nano-liposomal dual drug formulation for the treatment of HIV infection

AIMS

Development and characterization of LAM and DTG loaded liposomes conjugated anti-CD4 antibody and peptide dendrimer (PD2) to improve the therapeutic efficacy and to achieve targeted treatment for HIV infection.

MAIN METHODS

A 2-level full factorial design was used to optimize the preparation of dual drug loaded liposomes. Optimized dual drug loaded ligand conjugated liposomes were assessed for their cytotoxicity and cell internalization on TZM-bl cells. Anti-HIV efficiency of the dual drug loaded liposomes were screened for their inhibitory potential in TZM-bl cells and the activities were confirmed using Peripheral Blood Mononuclear Cells (PBMCs).

KEY FINDINGS

The particle size of the optimized dual drug-loaded liposomes was 133.7 ± 4.04 nm, and the spherical morphology of the liposomes was confirmed by TEM analysis. The entrapment efficiency was 34 ± 4.9 % and 54 ± 1.8 % for LAM and DTG, respectively, and a slower in vitro release of LAM and DTG was observed when entrapped into liposomes. The cytotoxicity of the dual drug loaded liposomes was similar to the cytotoxicity of free drug solutions. Conjugation of anti-CD4 antibody and PD2 did not significantly influence the cytotoxicity but it enhanced the uptake of liposomes into the cells. Conjugated dual drug loaded liposomes exhibited better HIV inhibition with lower IC50 values (0.0003 ± 0.0002 μg/mL) compared to their free drug solutions (0.002 ± 0.001 μg/mL). The liposomal formulations have shown similar activities in both screening and confirmatory cell-based assays.

SIGNIFICANCE

The results demonstrated the cell targeting ability of dual drug loaded liposomes conjugated with anti-CD4 antibody and peptide dendrimer. Conjugated liposomes also improved anti-HIV efficiency of LAM and DTG.

Surface modification strategies in translocating nano-vesicles across different barriers and the role of bio-vesicles in improving anticancer therapy

Nanovesicles and bio-vesicles (BVs) have emerged as promising tools to achieve targeted cancer therapy due to their ability to overcome many of the key challenges currently being faced with conventional chemotherapy. These challenges include the diverse and often complex pathophysiology involving the progression of cancer, as well as the various biological barriers that circumvent therapeutic molecules reaching their target site in optimum concentration. The scientific evidence suggests that surface-functionalized nanovesicles and BVs camouflaged nano-carriers (NCs) both can bypass the established biological barriers and facilitate fourth-generation targeting for the improved regimen of treatment. In this review, we intend to emphasize the role of surface-functionalized nanovesicles and BVs camouflaged NCs through various approaches that lead to an improved internalization to achieve improved and targeted oncotherapy. We have explored various strategies that have been employed to surface-functionalize and biologically modify these vesicles, including the use of biomolecule functionalized target ligands such as peptides, antibodies, and aptamers, as well as the targeting of specific receptors on cancer cells. Further, the utility of BVs, which are made from the membranes of cells such as mesenchymal stem cells (MSCs), white blood cells (WBCs), red blood cells (RBCs), platelets (PLTs) as well as cancer cells also been investigated. Lastly, we have discussed the translational challenges and limitations that these NCs can encounter and still need to be overcome in order to fully realize the potential of nanovesicles and BVs for targeted cancer therapy. The fundamental challenges that currently prevent successful cancer therapy and the necessity of novel delivery systems are in the offing.

Liposomal nanostructures for Gemcitabine and Paclitaxel delivery in pancreatic cancer

Pancreatic cancer (PC) is an incurable disease with a high death rate in the world nowadays. Gemcitabine (GEM) and Paclitaxel (PTX) are considered as references of chemotherapeutic treatments and are commonly used in clinical applications. Factors related to the tumor microenvironment such as insufficient tumor penetration, toxicity, and drug resistance can limit the effectiveness of these therapeutic anticancer drugs. The use of different liposomal nanostructures is a way that can optimize the drug's effectiveness and reduce toxicity. Given the development of PC therapy, this review focuses on advances in Nano-formulation, characterization, and delivery systems of loaded GEM and PTX liposomes using chemotherapy, nucleic acid delivery, and stroma remodeling therapy. As a result, the review covers the literature dealing with the applications of liposomes in PC therapy.

Nanoparticles in pancreatic cancer therapy: a detailed and elaborated review on patent literature

INTRODUCTION

Nanotechnology may open up new avenues for overcoming the challenges of pancreatic cancer therapy as a broad arsenal of anticancer medicines fail to realize their full therapeutic potential in pancreatic ductal adenocarcinoma due to the formation of multiple resistance mechanisms inside the tumor. Many studies have reported the successful use of various nano formulations in pancreatic cancer therapy.

AREAS COVERED

This review covers all the major nanotechnology-based patent litrature available on renowned patent data bases like Patentscope and Espacenet, through the time period of 2007-2022. This is an entirely patent centric review, and it includes both clinical and non-clinical data available on nanotechnology-based therapeutics and diagnostic tools for pancreatic cancer.

EXPERT OPINION

For the sake of understanding, the patents are categorized under various formulation-specific heads like metallic/non-metallic nanoparticles, polymeric nanoparticles, liposomes, carbon nanotubes, protein nanoparticles and liposomes. This distinguishes one specific nanoparticle type from another and makes this review a one-of-a-kind comprehensive patent compilation that has not been reported so far in the history of nanotechnological formulations in pancreatic cancer.

Development and characterization of lung surfactant-coated polymer nanoparticles for pulmonary drug delivery

Lung cancer is often diagnosed at an advanced stage where tumors are usually inoperable and first-line therapies are inefficient and have off-targeted adverse effects, resulting in poor patient survival. Here, we report the development of an inhalable poly lactic-co-glycolic acid polymer-based nanoparticle (PLGA-NP) formulation with a biomimetic Infasurf® lung surfactant (LS) coating, for localized and sustained lung cancer drug delivery. The nanoparticles (188 ± 7 nm) were stable in phosphate buffered saline, serum and Gamble's solution (simulated lung fluid), and demonstrated cytocompatibility up to 1000 μg/mL concentration and dose-dependent uptake by lung cancer cells. The LS coating significantly decreased nanoparticle (NP) uptake by NR8383 alveolar macrophages in vitro compared to uncoated NPs. The coating, however, did not impair NP uptake by A549 lung adenocarcinoma cells. The anti-cancer drug gemcitabine hydrochloride encapsulated in the PLGA core was released in a sustained manner while the paclitaxel loaded in the LS shell demonstrated a rapid or burst release profile over 21 days. The drug-loaded NPs significantly decreased cancer cell survival and colony formation in vitro compared to free drugs and single drug-loaded NPs. In vivo studies confirmed greater retention of LS-coated NPs in the lungs of C57BL/6 WT mice compared to uncoated NPs, at 24 h and 72 h following intranasal administration. The overall results confirm that LS coating is a unique strategy for cloaking polymeric NPs to potentially prevent their rapid lung clearance and facilitate prolonged pulmonary drug delivery.

Endothelial-Specific Targeting of RhoA Signaling via CD31 Antibody-Conjugated Nanoparticles

Existing vascular endothelial growth factor-oriented antiangiogenic approaches are known for their high potency. However, significant side effects associated with their use drive the need for novel antiangiogenic strategies. The small GTPase RhoA is an established regulator of actin cytoskeletal dynamics. Previous studies have highlighted the impact of endothelial RhoA pathway on angiogenesis. Rho-associate kinase (ROCK), a direct RhoA effector, is potently inhibited by Fasudil, a clinically relevant ROCK inhibitor. Here, we aimed to target the RhoA signaling in endothelial cells by generating Fasudil-encapsulated CD31-targeting liposomes as a potential antiangiogenic therapy. The liposomes presented desirable characteristics, preferential binding to CD31-expressing HEK293T cells and to endothelial cells, inhibited stress fiber formation and cytoskeletal-related morphometric parameters, and inhibited in vitro angiogenic functions. Overall, this work shows that the nanodelivery-mediated endothelial targeting of RhoA signaling can offer a promising strategy for angiogenesis inhibition in vascular-related diseases. SIGNIFICANCE STATEMENT: Systemic administration of antiangiogenic therapeutics induces side effects to non-targeted tissues. This study, among others, has shown the impact of the RhoA signaling in the endothelial cells and their angiogenic functions. Here, to minimize potential toxicity, this study generated CD31-targeting liposomes with encapsulated Fasudil, a clinically relevant Rho kinase inhibitor, and successfully targeted endothelial cells. In this proof-of-principle study, the efficient Fasudil delivery, its impact on the endothelial signaling, morphometric alterations, and angiogenic functions verify the benefits of site-targeted antiangiogenic therapy.

Efficient Delivery of Gemcitabine by Estrogen Receptor-Targeted PEGylated Liposome and Its Anti-Lung Cancer Activity In Vivo and In Vitro

Lung cancer is one of the main causes of cancer-related deaths. At present, the main treatment method for lung cancer is chemotherapy. Gemcitabine (GEM) is widely applied in lung cancer treatment, but its lack of targeting ability and serious side effects limit its application. In recent years, nanocarriers have become the focus of research to solve the above problems. Here, we prepared estrone (ES)-modified GEM-loaded PEGylated liposomes (ES-SSL-GEM) for enhanced delivery by identifying the overexpressed estrogen receptor (ER) on lung cancer A549 cells. We studied the characterization, stability, release behavior, cytotoxicity, targeting ability, endocytosis mechanism, and antitumor ability to prove the therapeutic effect of ES-SSL-GEM. The results showed that ES-SSL-GEM presented a uniform particle size of 131.20 ± 0.62 nm, a good stability, and a slowly released behavior. Moreover, ES-SSL-GEM enhanced tumor-targeting ability, and the endocytosis mechanism studies confirmed that the ER-mediated endocytosis had the most crucial effect. Furthermore, ES-SSL-GEM had the best inhibitory effect on A549 cell proliferation and significantly suppressed the tumor growth in vivo. These results suggest that ES-SSL-GEM is a promising agent for treating lung cancer.

Liposome-based diagnostic and therapeutic applications for pancreatic cancer

Pancreatic cancer is one of the harshest and most challenging cancers to treat, often labeled as incurable. Chemotherapy continues to be the most popular treatment yet yields a very poor prognosis. The main barriers such as inefficient drug penetration and drug resistance, have led to the development of drug carrier systems. The benefits, ease of fabrication and modification of liposomes render them as ideal future drug delivery systems. This review delves into the versatility of liposomes to achieve various mechanisms of treatment for pancreatic cancer. Not only are there benefits of loading chemotherapy drugs and targeting agents onto liposomes, as well as mRNA combined therapy, but liposomes have also been exploited for immunotherapy and can be programmed to respond to photothermal therapy. Multifunctional liposomal formulations have demonstrated significant pre-clinical success. Functionalising drug-encapsulated liposomes has resulted in triggered drug release, specific targeting, and remodeling of the tumor environment. Suppressing tumor progression has been achieved, due to their ability to more efficiently and precisely deliver chemotherapy. Currently, no multifunctional surface-modified liposomes are clinically approved for pancreatic cancer thus we aim to shed light on the trials and tribulations and progress so far, with the hope for liposomal therapy in the future and improved patient outcomes. STATEMENT OF SIGNIFICANCE: Considering that conventional treatments for pancreatic cancer are highly associated with sub-optimal performance and systemic toxicity, the development of novel therapeutic strategies holds outmost relevance for pancreatic cancer management. Liposomes are being increasingly considered as promising nanocarriers for providing not only an early diagnosis but also effective, highly specific, and safer treatment, improving overall patient outcome. This manuscript is the first in the last 10 years that revises the advances in the application of liposome-based formulations in bioimaging, chemotherapy, phototherapy, immunotherapy, combination therapies, and emergent therapies for pancreatic cancer management. Prospective insights are provided regarding several advantages resulting from the use of liposome technology in precision strategies, fostering new ideas for next-generation diagnosis and targeted therapies of pancreatic cancer.

Nanotechnology as a tool to overcome macromolecules delivery issues

Nanocarriers can deliver drugs to specific organs or cells, potentially bridging the gap between a drug's function and its interaction with biological systems such as human physiology. The untapped potential of nanotechnology stems from its ability to manipulate materials, allowing control over physical and chemical properties and overcoming drug-related problems, e.g., poor solubility or poor bioavailability. For example, most protein drugs are administered parenterally, each with challenges and peculiarities. Some problems faced by bioengineered macromolecule drugs leading to poor bioavailability are short biological half-life, large size and high molecular weight, low permeability through biological membranes, and structural instability. Nanotechnology emerges as a promising strategy to overcome these problems. Nevertheless, the delivery system should be carefully chosen considering loading efficiency, physicochemical properties, production conditions, toxicity, and regulations. Moving from the bench to the bedside is still one of the major bottlenecks in nanomedicine, and toxicological issues are the greatest challenges to overcome. This review provides an overview of biotech drug delivery approaches, associated nanotechnology novelty, toxicological issues, and regulations.

Lipid Nanoparticles Functionalized with Antibodies for Anticancer Drug Therapy

Nanotechnology takes the lead in providing new therapeutic options for cancer patients. In the last decades, lipid-based nanoparticles-solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs), liposomes, and lipid-polymer hybrid nanoparticles-have received particular interest in anticancer drug delivery to solid tumors. To improve selectivity for target cells and, thus, therapeutic efficacy, lipid nanoparticles have been functionalized with antibodies that bind to receptors overexpressed in angiogenic endothelial cells or cancer cells. Most papers dealing with the preclinical results of antibody-conjugated nanoparticles claim low systemic toxicity and effective tumor inhibition, which have not been successfully translated into clinical use yet. This review aims to summarize the current "state-of-the-art" in anticancer drug delivery using antibody-functionalized lipid-based nanoparticles. It includes an update on promising candidates that entered clinical trials and some explanations for low translation success.

Phytochemical-loaded liposomes for anticancer therapy: an updated review

The major obstacles observed in current chemotherapy are severe adverse effects, narrow therapeutic indexes and multidrug resistance. Anticancer phytochemicals are extracted and purified from natural plants, providing alternative therapeutic approaches with recognized biomedical benefits. However, poor bioavailability, high dose requirements and non-specific targeting have made those molecules less effective. To tackle those issues, liposomal nanovesicles for phytochemical delivery are taken into consideration for improving the therapeutic effectiveness by increasing transportation across cell barriers and conferring attractive cancer-specific targeting capabilities. In the present review, the liposomal approaches of anticancer phytochemicals are discussed, and recent advances in these formulations applied to cancer phytotherapy are further reviewed by an informed approach.

Nanocarriers targeting the diseases of the pancreas

Diseases of the pancreas include acute and chronic pancreatitis, exocrine pancreatic insufficiency, diabetes and pancreatic cancer. These pathologies can be difficult to treat due to the innate properties of the pancreas, its structure and localization. The need for effective targeting of the pancreatic tissue by means of nanoparticles delivering therapeutics is a major focus area covered and discussed in this review. Most common diseases of the pancreas do not have specific and direct medical treatment option, and existing treatment options are generally aimed at relieving symptoms. Diabetes has different treatment options for different subtypes based on insulin having stability problems and requiring injections reducing patient compliance. Pancreatic cancer progresses silently and can only be diagnosed in advanced stages. Therefore, survival rate of patients is very low. Gemcitabine and FOLFIRINOX treatment regimens, the most commonly used clinical standard treatments, are generally insufficient due to the chemoresistance that develops in cancer cells and also various side effects. Therefore new treatment options for pancreatic cancer are also under focus. Overcoming drug resistance and pancreatic targeting can be achieved with active and passive targeting methods, and a more effective and safer treatment regimen can be provided at lower drug doses. This review covers the current literature and clinical trials concerning pancreatic drug delivery systems in the nanoscale focusing on the challenges and opportunities provided by these smart delivery systems.

A sulfobetaine zwitterionic polymer-drug conjugate for multivalent paclitaxel and gemcitabine co-delivery

A zwitterionic polymer-drug conjugate (ZPDC) strategy is developed for the co-delivery of paclitaxel (PTX) and gemcitabine (GEM) chemotherapeutics, as well as a near-infrared fluorescence imaging agent cyanine5.5 (Cy5.5). The well-defined ZPDC is synthesized by tandem azide-alkyne and thiol-ene click functionalization of a biodegradable acetylenyl/allyl-functionalized polylactide and zwitterionic character is conferred by sulfobetaine. It has a number-average molecular weight of 53.6 kDa, comprising 6.5% PTX and 17.7% GEM by weight. Cy5.5 moieties are readily introduced to the ZPDC via conjugation. In aqueous solutions, the ZPDC exhibits a hydrodynamic diameter of 46 nm. In vitro MIA PaCa-2 human pancreatic cancer cells show strong ZPDC cellular uptake and cytotoxicity. In mice, the ZPDC exhibits long blood circulation, effective tumor accumulation, biocompatibility, therapeutic effect, and integrated imaging capacity. Overall, this work illustrates that ZPDCs are promising systems for chemotherapy delivery and bioimaging applications.

Recent Advances in Lipid-Based Nanosystems for Gemcitabine and Gemcitabine-Combination Therapy

The anti-metabolite drug gemcitabine is widely used for the treatment of a variety of cancers. At present, gemcitabine is administered as a hydrochloride salt that is delivered by slow intravenous injection in cycles of three or four weeks. Although regarded as a 'front-line' chemotherapeutic agent, its efficacy is hampered by poor target cell specificity, sub-optimal cellular uptake, rapid clearance from circulation, the development of chemoresistance, and undesirable side-effects. The use of organic, inorganic, and metal-based nanoparticles as delivery agents presents an opportunity to overcome these limitations and safely harness optimal drug efficacy and enhance their therapeutic indices. Among the many and varied nano delivery agents explored, the greatest body of knowledge has been generated in the field of lipid-mediated delivery. We review here the liposomes, niosomes, solid lipid nanoparticles, nanostructured lipid carriers, exosomes, lipid-polymer hybrids, and other novel lipid-based agents that have been developed within the past six years for the delivery of gemcitabine and its co-drugs.

Thermosensitive and biodegradable hydrogel encapsulating targeted nanoparticles for the sustained co-delivery of gemcitabine and paclitaxel to pancreatic cancer cells

Pancreatic cancer represents a life threatening disease with rising mortality. Although the synergistic combination of gemcitabine and albumin-bound paclitaxel has proven to enhance the median survival rates as compared to gemcitabine alone, their systemic and repeated co-administration has been associated with serious toxic side effects and poor patient compliance. For this purpose, we designed a thermosensitive and biodegradable hydrogel encapsulating targeted nanoparticles for the local and sustained delivery of gemcitabine (GEM) and paclitaxel (PTX) to pancreatic cancer. GEM and PTX were loaded into PR_b-functionalized liposomes targeting integrin α₅β₁, which was shown to be overexpressed in pancreatic cancer. PR_b is a fibronectin-mimetic peptide that binds to α₅β₁ with high affinity and specificity. The PR_b liposomes were encapsulated into a poly(δ-valerolactone-co-D,L-lactide)-b-poly(ethylene glycol)-b-poly(δ-valerolactone-co-D,L-lactide) (PVLA-PEG-PVLA) hydrogel and demonstrated sustained release of both drugs compared to PR_b-functionalized liposomes free in solution or free drugs in the hydrogel. Moreover, the hydrogel-nanoparticle system was proven to be very efficient towards killing monolayers of human pancreatic cancer cells (PANC-1), and showed a significant reduction in the growth pattern of PANC-1 tumor spheroids as compared to hydrogels encapsulating non-targeted liposomes with GEM/PTX or free drugs, after a one week treatment period. Our hybrid hydrogel-nanoparticle system is a promising platform for the local and sustained delivery of GEM/PTX to pancreatic cancer, with the goal of maximizing the therapeutic efficacy of this synergistic drug cocktail while potentially minimizing toxic side effects and eliminating the need for repeated co-administration.

Targeted Dual Intervention-Oriented Drug-Encapsulated (DIODE) Nanoformulations for Improved Treatment of Pancreatic Cancer

Despite recent advancements, effective treatment for pancreatic ductal adenocarcinoma (PDAC) has remained elusive. The overall survival rate in PDAC patients has been dismally low due to resistance to standard therapies. In fact, the failure of monotherapies to provide long-term survival benefits in patients led to ascension of several combination therapies for PDAC treatment. However, these combination therapies provided modest survival improvements while increasing treatment-related adverse side effects. Hence, recent developments in drug delivery methods hold the potential for enhancing therapeutic benefits by offering cocktail drug loading and minimizing chemotherapy-associated side effects. Nanoformulations-aided deliveries of anticancer agents have been a success in recent years. Yet, improving the tumor-targeted delivery of drugs to PDAC remains a major hurdle. In the present paper, we developed several new tumor-targeted dual intervention-oriented drug-encapsulated (DIODE) liposomes. We successfully formulated liposomes loaded with gemcitabine (G), paclitaxel (P), erlotinib (E), XL-184 (c-Met inhibitor, X), and their combinations (GP, GE, and GX) and evaluated their in vitro and in vivo efficacies. Our novel DIODE liposomal formulations improved median survival in comparison with gemcitabine-loaded liposomes or vehicle. Our findings are suggestive of the importance of the targeted delivery for combination therapies in improving pancreatic cancer treatment.

Interlink between improved formulations, inhibitory concentrations and cell death mechanism investigations of cytotoxic drugs: What really matters?

In this article, IC₅₀ concentrations derived from MTT assay for further evaluating of cell death induced by new formulations were discussed. This review attempts to introduce an enhanced approach for evaluation of cell death mechanisms based on routine cytotoxicity assays for anti-cancer medications. It is highly desirable for anti-cancer drugs to induce apoptotic cell death in order to have better efficacy and less complications. According to our previous results and other comparable studies, cell death mechanisms and phenotypes followed by cytotoxic drugs are rigorously concentration dependent; therefore, calculated IC₅₀s obtained through cytotoxicity assays should be exactly employed for evaluating of cell death mechanisms. More appropriately, it is better to select concentrations which are closer to the efficient plasma levels for additional cell death evaluations. If enough amounts of new formulated materials are available, it is suggested to calculate and compare IC₅₀s for old and improved formulations at different concentration ranges; otherwise, when materials are not sufficiently available or the toxicity of new formulation is not high enough to yield an IC₅₀, then some specific point to point comparison between corresponding concentrations within a reasonable range should be made. Another important point is that IC₅₀ values obtained via in vitro assays are frequently higher than in vivo or therapeutic plasma concentrations and it seems better to use improved formulation^'s IC₅₀s which are more comparable to clinical plasma concentrations or consider IC₂₅s of free drugs for determination of cell death mechanisms.

A promising cancer diagnosis and treatment strategy: targeted cancer therapy and imaging based on antibody fragment

With the arrival of the precision medicine and personalized treatment era, targeted therapy that improves efficacy and reduces side effects has become the mainstream approach of cancer treatment. Antibody fragments that further enhance penetration and retain the most critical antigen-specific binding functions are considered the focus of research targeting cancer imaging and therapy. Thanks to the superior penetration and rapid blood clearance of antibody fragments, antibody fragment-based imaging agents enable efficient and sensitive imaging of tumour sites. In tumour-targeted therapy, antibody fragments can directly inhibit tumour proliferation and growth, serve as an ideal carrier for delivery of anti-tumour drugs, or manipulate the immune system to eliminate tumour cells. In this review, the excellent physicochemical properties and the basic structure of antibody fragments are expressly depicted depicted, the progress of antibody fragments in cancer therapy and imaging are thoroughly summarized, and the future development of antibody fragments is predicted.

Functionalizing nanoparticles with cancer-targeting antibodies: A comparison of strategies

Standard cancer therapies sometimes fail to deliver chemotherapeutic drugs to tumor cells in a safe and effective manner. Nanotechnology takes the lead in providing new therapeutic options for cancer due to major potential for selective targeting and controlled drug release. Antibodies and antibody fragments are attracting much attention as a source of targeting ligands to bind specific receptors that are overexpressed on cancer cells. Therefore, researchers are devoting time and effort to develop targeting strategies based on nanoparticles functionalized with antibodies, which hold great promise to enhance therapeutic efficacy and circumvent severe side effects. Several methods have been described to immobilize antibodies on the surface of nanoparticles. However, selecting the most appropriate for each application is challenging but also imperative to preserve antigen binding ability and yield stable antibody-conjugated nanoparticles. From this perspective, we aim to provide considerable knowledge on the most widely used methods of functionalization that can be helpful for decision-making and design of conjugation protocols as well. This review summarizes adsorption, covalent conjugation (carbodiimide, maleimide and "click" chemistries) and biotin-avidin interaction, while discussing the advantages, limitations and relevant therapeutic approaches currently under investigation.

ADCs, as Novel Revolutionary Weapons for Providing a Step Forward in Targeted Therapy of Malignancies

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Antibody drug conjugates (ADCs), as potent pharmaceutical trojan horses for cancer treatment, provide superior efficacy and specific targeting along with low risk of adverse reactions compared to traditional chemotherapeutics. In fact, the development of these agents combines the selective targeting capability of monoclonal antibody (mAb) with high cytotoxicity of chemotherapeutics for controlling the neoplastic mass growth. Different ADCs (more than 60 ADCs) in preclinical and clinical trials were introduced in this novel pharmaceutical field. Various design-based factors must be taken into account for improving the functionality of ADC technology, including selection of appropriate target antigen and high binding affinity of fragment (miniaturized ADCs) or full mAbs (preferentially use of humanized or fully human antibodies compared to murine and chimeric ones), use of bispecific antibodies for dual targeting effect, linker engineering and conjugation method efficacy to obtain more controlled drug to antibody ratio (DAR). Challenging issues affecting therapeutic efficacy and safety of ADCs, including bystander effect, on- and off-target toxicities, multi drug resistance (MDR) are also addressed. 4 FDA-approved ADCs in the market, including ADCETRIS ®, MYLOTARG®, BESPONSA ®, KADCYLA®. The goal of the current review is to evaluate the key parameters affecting ADCs development.

Liposomes modified with bio-substances for cancer treatment

In recent years, liposomes have been used in the field of biomedicine and have achieved many significant results.

Preparation, Characterization, and in Vitro/in Vivo Evaluation of Paclitaxel-Bound Albumin-Encapsulated Liposomes for the Treatment of Pancreatic Cancer

Paclitaxel (PTX)-loaded liposomes were developed with the goal of enhancing the effects of cancer treatment. Although loading substances into the lipid membrane of liposome cause some destabilization of the lipid membrane, PTX was nearly exclusively embedded in the lipid membrane of liposomes, due to its low water solubility. Hydrophobic drugs can be encapsulated into the inner core of bovine serum albumin (BSA)-encapsulated liposomes (BSA-liposome) via noncovalent binding to albumin. Since PTX is able to noncovalently bind to albumin, we attempted to prepare PTX-loaded BSA-liposome (PTX-BSA-liposome). The amount of PTX loaded in the BSA-liposome could be increased substantially by using ethanol, since ethanol increases PTX solubility in BSA solutions via prompting the binding PTX to BSA. On the basis of the results of transmission electron microscopy and small-angle X-ray scattering, PTX-BSA-liposome formed unilamellar vesicles that were spherical in shape and the PTX was encapsulated into the inner aqueous core of the liposome as a form of PTX-BSA complex. In addition, the PTX-BSA-liposome, as well as nab-PTX, showed cytotoxicity against human pancreatic cancer cells, AsPC-1 cells, in a PTX concentration-dependent manner. The in vivo antitumor effect of PTX-BSA-liposomes was also observed in a mouse model that had been subcutaneously inoculated with pancreatic cancer cells by virtue of its high accumulation at the tumor site via the enhanced permeability retention effect. These results suggest that PTX-BSA-liposomes have the potential for serving as a novel PTX preparation method for the treatment of pancreatic cancer.

A multifunctional biodegradable brush polymer-drug conjugate for paclitaxel/gemcitabine co-delivery and tumor imaging

A multifunctional biodegradable brush polymer-drug conjugate (BPDC) is developed for the co-delivery of hydrophobic paclitaxel (PTX) and hydrophilic gemcitabine (GEM) chemotherapeutics, as well as a tumor imaging agent. A novel ternary copolymer of conventional, acetylenyl-functionalized and allyl-functionalized lactides is prepared to serve as the backbone precursor of BPDC. Acetylenyl groups of the copolymer are then reacted with poly(ethylene glycol) (PEG) side chains and cyanine5.5, a fluorescent probe, via azide-alkyne click reactions. Subsequently, the allyl groups of the yielded PEG-grafted brush polymer are used to covalently link PTX and GEM onto the backbone via thiol-ene click reactions. The resulting BPDC exhibits an average hydrodynamic diameter of 111 nm. Sustained and simultaneous release of PTX and GEM from the BPDC is observed in phosphate buffered saline, with the release of PTX showing sensitivity in mild acidic conditions. In vitro studies using MIA PaCa-2 human pancreatic cancer cells illustrate the cellular uptake and cytotoxicity of the BPDC. In vivo, the BPDC possesses long blood circulation, tumor accumulation, and enables optical tumor imaging. Further development and testing is warranted for multifunctional conjugated brush polymer systems that integrate combination chemotherapies and imaging.

Diosgenin-loaded niosome as an effective phytochemical nanocarrier: physicochemical characterization, loading efficiency, and cytotoxicity assay

BACKGROUND

The use of phytochemicals to prevent or suppress tumours is known as chemoprevention. Numerous plant-derived agents have been reported to have anticancer potentials. As one such anticancer phytochemical, diosgenin has several applications which are nevertheless limited due to its low solubility in water.

METHODS

We loaded diosgenin into niosome to increase its solubility and hence efficiency. Diosgenin-niosome (diosgenin loaded into niosome) was prepared by thin-film hydration method and characterised by optical microscopy, dynamic light scattering (DLS), scanning electron microscopy (SEM), and UV-visible spectrophotometry. Also, loading efficiency, in vitro drug release, and cytotoxicity assay were performed on HepG2 cell line.

RESULTS AND DISCUSSION

Diosgenin-niosome has a nanometric size with a normal size distribution and spherical morphology. The loading efficiency of diosgenin was about 89% with a sustainable and controllable release rate. Finally, the viability of free diosgenin was 61.25%, and after loading into niosomes, it was improved to 28.32%.

CONCLUSION

The results demonstrated that niosomes increase the solubility of naturally derived hydrophobic chemicals and thus enhance their anticancer effect. Graphical abstract.

Liposome: composition, characterisation, preparation, and recent innovation in clinical applications

In the last decades, pharmaceutical interested researches aimed to develop novel and innovative drug delivery techniques in the medical and pharmaceutical fields. Recently, phospholipid vesicles (Liposomes) are the most known versatile assemblies in the drug delivery systems. The discovery of liposomes arises from self-forming enclosed phospholipid bilayer upon coming in contact with the aqueous solution. Liposomes are uni or multilamellar vesicles consisting of phospholipids produced naturally or synthetically, which are readily non-toxic, biodegradable, and are readily produced on a large scale. Various phospholipids, for instance, soybean, egg yolk, synthetic, and hydrogenated phosphatidylcholine consider the most popular types used in different kinds of formulations. This review summarises liposomes composition, characterisation, methods of preparation, and their applications in different medical fields including cancer therapy, vaccine, ocular delivery, wound healing, and some dermatological applications.

Drug delivery systems for elemene, its main active ingredient β-elemene, and its derivatives in cancer therapy

β-elemene is a noncytotoxic Class II antitumor drug extracted from the traditional Chinese medicine Curcuma wenyujin Y. H. Chen et C. Ling. β-elemene exerts its effects by inhibiting cell proliferation, arresting the cell cycle, inducing cell apoptosis, exerting antiangiogenesis and antimetastasis effects, reversing multiple-drug resistance (MDR), and enhancing the immune system. Elemene injection and oral emulsion have been used to treat various tumors, including cancer of the lung, liver, brain, breast, ovary, gastric, prostate, and other tissues, for >20 years. The safety of both elemene injection and oral emulsion in the clinic has been discussed. Recently, the secondary development of β-elemene has attracted the attention of researchers and made great progress. On the one hand, studies have been carried out on liposome-based systems (including solid lipid nanoparticles [SLNs], nanostructured lipid carriers [NLCs], long-circulating liposomes, active targeting liposomes, and multidrug-loaded liposomes) and emulsion systems (including microemulsions, self-emulsion drug delivery systems [SEDDSs], and active targeting microemulsion) to solve the issues of poor solubility in water, low bioavailability, and severe phlebitis, as well as to improve antitumor efficacy. The pharmacokinetics of different drug delivery systems of β-elemene are also summarized. On the other hand, a number of highly active anticancer β-elemene derivatives have been obtained through modification of the structure of β-elemene. This review focuses on the two drug delivery systems and derivatives of β-elemene for cancer therapy.