Smart polymeric nanoparticles with pH-responsive and PEG-detachable properties for co-delivering paclitaxel and survivin siRNA to enhance antitumor outcomes

Targeted melanoma therapy: High-efficiency siRNA delivery with R8-PEI dissolvable microneedles

Cutaneous melanoma, characterized by its high malignancy and propensity for early metastasis, has become one of the most lethal forms of skin cancer. RNA interference (RNAi) presents a promising therapeutic strategy for melanoma by using small interfering RNAs (siRNAs) to silence gene expression. However, the clinical application of RNAi is hindered by challenges associated with siRNA delivery, including degradation by nucleases, limited cellular uptake, and the barrier of the stratum corneum. In this study, we developed a carrier system comprising of polyethyleneimine (PEI) modified with octamer arginine (R8), a cell-penetrating peptide, and utilized this modified PEI to fabricate dissolvable microneedles loaded with siRNA (siRNA@R8-PEI/DMNs).The siRNA@R8-PEI/DMNs exhibited an excellent overall appearance, featuring a flat backing layer and a needle content of (93.92 ± 4.23)%. The microneedles demonstrated robust mechanical strength,with an overall force of (62.13 ± 8.93) N and a tip strength of (1.69 ± 0.37) N, facilitating effective penetration through the Parafilm®M membrane to a depth of approximately 380 μm. In vitro puncture tests on rat skin revealed a puncture rate exceeding 80%, indicating the system's strong capability to penetrate the skin. In vitro cellular experiments demonstrated that siRNA@R8-PEI effectively inhibited the proliferation of A375 cells by approximately 90% in a concentration-dependent manner. Additionally, the 24-hour cell migration rate was reduced to approximately 20%, and the gene silencing efficiency reached up to about 74%. In vivo studies further confirmed the therapeutic potential of siRNA@R8-PEI/DMNs, with a volumetric tumor inhibition rate of about 67%, inducing tumor cell apoptosis and reducing BRAF expression.siRNA@R8-PEI/DMNs offer a promising transdermal siRNA delivery system for cutaneous melanoma therapy, potentially providing novel insights into the development of safe and efficient transdermal siRNA delivery vectors. This study lays the groundwork for further exploration of RNAi-based therapeutics in dermatological oncology.

Inulin and hyaluronic acid-based oral liposome for enhanced photo-chemotherapy against orthotopic colon cancer and its reversal effects on tumor hypoxia and intestinal microbiota

Colon cancer has a complex microenvironment and course, and conventional chemotherapy is hindered by low permeability and immunosuppression at the cancer site, leading to poor efficacy. Integrating intestinal environment regulation and molecularly targeted drugs are more attractive strategies. This study aimed to developed an oral colonic targeted delivery system (5-Flu/MET@MSNs/Ce6@HIL) using hyaluronic acid (HA) and inulin (IN) as key components. IN is a polymer with colon-specific targeting capabilities, while HA targets CD44 on the surface of colon cancer cells. We used IN and HA-modified liposomes to co-encapsulate three therapeutic agents, chemotherapy drug 5-Fluorouracil (5-Flu), photosensitizer chlorin e6 (Ce6), and hypoxia reliever metformin (MET). 5-Flu and Ce6 effectively induced cell apoptosis, whereas MET downregulated Hypoxia-Inducible Factor 1-α (HIF-1α) and alleviate the hypoxic microenvironment. In orthotopic colon-tumor-bearing-mice, the final product of 5-Flu@MET@MSNs/Ce6@HIL effectively hindered growth of tumors, which was inhibited by 3.31, 14.31, and 7.88 times when compared to 5-Flu, MET, or Ce6 single-loaded formulations, respectively. Furthermore, after oral administration, the multifunctional liposomes showed good in vivo safety and compliance. In conclusion, this study proposes a novel orthotopic colon-targeted cancer treatment strategy with accurate tumor targeting capabilities, which has certain potential and development value in future clinical applications.

Polymeric nanocarriers for therapeutic gene delivery

The recent commercialization of gene products has sparked significant interest in gene therapy, necessitating efficient and precise gene delivery via various vectors. Currently, viral vectors and lipid-based nanocarriers are the predominant choices and have been extensively investigated and reviewed. Beyond these vectors, polymeric nanocarriers also hold the promise in therapeutic gene delivery owing to their versatile functionalities, such as improving the stability, cellar uptake and endosomal escape of nucleic acid drugs, along with precise delivery to targeted tissues. This review presents a brief overview of the status quo of the emerging polymeric nanocarriers for therapeutic gene delivery, focusing on key cationic polymers, nanocarrier types, and preparation methods. It also highlights targeted diseases, strategies to improve delivery efficiency, and potential future directions in this research area. The review is hoped to inspire the development, optimization, and clinical translation of highly efficient polymeric nanocarriers for therapeutic gene delivery.

Targeted Nanotherapy by Vinblastine-Loaded Chitosan-Coated PLA Nanoparticles to Improve the Chemotherapy via Reactive Oxygen Species to Hamper Hepatocellular Carcinoma

Liver cancer is a prevalent and significant cause of death in humans. The use of novel biodegradable materials for various biomedical applications is being recently recommended as complementary as well as alternative solution for traditional chemotherapy. This study focuses on the synthesis of biodegradable nanocarriers [chitosan-coated poly(lactic acid) NPs (Cht-PLA NPs)] for the delivery of an anticancer drug vinblastine (Vbx) and to evaluate its therapeutic potential in human hepatocellular carcinoma (HepG2) cells. The Cht-PLA NPs were synthesized using the nanoprecipitation method and characterized by transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, dynamic light scattering, and zeta potential techniques. The results showed that the nanoparticle sizes are in the range of 100-200 nm with positive surface charge. The release profile of the synthesized nanoformulation showed controlled release of the Vbx drug for 72 h. The anticancer efficacy of the synthesized nanoformulation was assessed on the HepG2 cell lines. The in vitro cytotoxicity study revealed that the Vbx-loaded Cht-PLA NPs showed higher toxicity with an increase in concentration as compared to the Vbx alone. Additionally, an in vitro cellular uptake study revealed higher internalization as compared to the drug alone due to the chitosan coating. Further, the ability to stimulate the reactive oxygen species (ROS) generation and variation in mitochondrial membrane potential at the IC50 concentration of Vbx-loaded Cht-PLA NPs was confirmed by using 2,7-dichlorodihydrofluorescein diacetate and rhodamine 123 dyes, respectively, and were analyzed under fluorescence microscopy. Hence, the results showed that Vbx-loaded Cht-PLA NPs possess high anticancer activity due to its higher cellular toxicity, cellular uptake, increased ROS production, and disruption in mitochondrial membrane potential. All these properties of the synthesized nanoformulation suggest it's potential applications in drug delivery systems, targeting liver cancer.

Targeting the lung tumour stroma: harnessing nanoparticles for effective therapeutic interventions

Lung cancer remains an influential global health concern, necessitating the development of innovative therapeutic strategies. The tumour stroma, which is known as tumour microenvironment (TME) has a central impact on tumour expansion and treatment resistance. The stroma of lung tumours consists of numerous cells and molecules that shape an environment for tumour expansion. This environment not only protects tumoral cells against immune system attacks but also enables tumour stroma to attenuate the action of antitumor drugs. This stroma consists of stromal cells like cancer-associated fibroblasts (CAFs), suppressive immune cells, and cytotoxic immune cells. Additionally, the presence of stem cells, endothelial cells and pericytes can facilitate tumour volume expansion. Nanoparticles are hopeful tools for targeted drug delivery because of their extraordinary properties and their capacity to devastate biological obstacles. This review article provides a comprehensive overview of contemporary advancements in targeting the lung tumour stroma using nanoparticles. Various nanoparticle-based approaches, including passive and active targeting, and stimuli-responsive systems, highlighting their potential to improve drug delivery efficiency. Additionally, the role of nanotechnology in modulating the tumour stroma by targeting key components such as immune cells, extracellular matrix (ECM), hypoxia, and suppressive elements in the lung tumour stroma.

Targeting breast tumor extracellular matrix and stroma utilizing nanoparticles

Breast cancer is a complicated malignancy and is known as the most common cancer in women. Considerable experiments have been devoted to explore the basic impacts of the tumor stroma, particularly the extracellular matrix (ECM) and stromal components, on tumor growth and resistance to treatment. ECM is made up of an intricate system of proteins, glycosaminoglycans, and proteoglycans, and maintains structural support and controls key signaling pathways involved in breast tumors. ECM can block different drugs such as chemotherapy and immunotherapy drugs from entering the tumor stroma. Furthermore, the stromal elements, such as cancer-associated fibroblasts (CAFs), immune cells, and blood vessels, have crucial impacts on tumor development and therapeutic resistance. Recently, promising outcomes have been achieved in using nanotechnology for delivering drugs to tumor stroma and crossing ECM in breast malignancies. Nanoparticles have various benefits for targeting the breast tumor stroma, such as improved permeability and retention, extended circulation time, and the ability to actively target the area. This review covers the latest developments in nanoparticle therapies that focus on breast tumor ECM and stroma. We will explore different approaches using nanoparticles to target the delivery of anticancer drugs like chemotherapy, small molecule drugs, various antitumor products, and other specific synthetic therapeutic agents to the breast tumor stroma. Furthermore, we will investigate the utilization of nanoparticles in altering the stromal elements, such as reprogramming CAFs and immune cells, and also remodeling ECM.

Selective imaging, gene, and therapeutic delivery using PEGylated and pH-Sensitive nanoparticles for enhanced lung disorder treatment

Lung inflammation involves the activation of immune cells and inflammatory mediators in response to injury and infection. When inflammation persists, fibroblasts, which are resident lung cells, become activated, leading to pulmonary fibrosis (PF), abnormal wound healing, and long-term damage to the alveolar epithelium. This persistent inflammation and fibrosis can also elevate the risk of lung cancer, emphasizing the need for innovative treatments. Current therapies, such as inhaled corticosteroids (ICS) and chemotherapy, have significant limitations. Although conventional nanoparticles (NPs) provide a promising avenue for treating lung disorders, they have limited selectivity and stability. Polyethylene glycol (PEG) grafting can prevent NP aggregation and phagocytosis, thus prolonging their circulation time. When combined with targeting ligands, PEGylated NPs can deliver drugs precisely to specific cells or tissues. Moreover, pH-sensitive NPs offer the advantage of selective drug delivery to inflammatory or tumor-acidic environments, reducing side effects. These NPs can change their size, shape, or surface charge in response to pH variations, improving drug delivery efficiency. This review examines the techniques of PEGylation, the polymers used in pH-sensitive NPs, and their therapeutic applications for lung inflammation, fibrosis, and cancer. By harnessing innovative NP technologies, researchers can develop effective therapies for respiratory conditions, addressing unmet medical needs and enhancing patient outcomes.

Preparation and effects of functionalized liposomes targeting breast cancer tumors using chemotherapy, phototherapy, and immunotherapy

Breast cancer therapy has significantly advanced by targeting the programmed cell death-ligand 1/programmed cell death-1 (PD-L1/PD-1) pathway. BMS-202 (a smallmolecule PD-L1 inhibitor) induces PD-L1 dimerization to block PD-1/PD-L1 interactions, allowing the T-cell-mediated immune response to kill tumor cells. However, immunotherapy alone has limited effects. Clinically approved photodynamic therapy (PDT) activates immunity and selectively targets malignant cells. However, PDT aggravates hypoxia, which may compromise its therapeutic efficacy and promote tumor metastasis. We designed a tumor-specific delivery nanoplatform of liposomes that encapsulate the hypoxia-sensitive antitumor drug tirapazamine (TPZ) and the small-molecule immunosuppressant BMS. New indocyanine green (IR820)-loaded polyethylenimine-folic acid (PEI-FA) was complexed with TPZ and BMS-loaded liposomes via electrostatic interactions to form lipid nanocomposites. This nanoplatform can be triggered by near-infrared irradiation to induce PDT, resulting in a hypoxic tumor environment and activation of the prodrug TPZ to achieve efficient chemotherapy. The in vitro and in vivo studies demonstrated excellent combined PDT, chemotherapy, and immunotherapy effects on the regression of distant tumors and lung metastases, providing a reference method for the preparation of targeted agents for treating breast cancer.

Polypeptide-based multilayer nanoarchitectures: Controlled assembly on planar and colloidal substrates for biomedical applications

Polypeptides have shown an excellent potential in nanomedicine thanks to their biocompatibility, biodegradability, high functionality, and responsiveness to several stimuli. Polypeptides exhibit high propensity to organize at the supramolecular level; hence, they have been extensively considered as building blocks in the layer-by-layer (LbL) assembly. The LbL technique is a highly versatile methodology, which involves the sequential assembly of building blocks, mainly driven by electrostatic interactions, onto planar or colloidal templates to fabricate sophisticated multilayer nanoarchitectures. The simplicity and the mild conditions required in the LbL approach have led to the inclusion of biopolymers and bioactive molecules for the fabrication of a wide spectrum of biodegradable, biocompatible, and precisely engineered multilayer films for biomedical applications. This review focuses on those examples in which polypeptides have been used as building blocks of multilayer nanoarchitectures for tissue engineering and drug delivery applications, highlighting the characteristics of the polypeptides and the strategies adopted to increase the stability of the multilayer film. Cross-linking is presented as a powerful strategy to enhance the stability and stiffness of the multilayer network, which is a fundamental requirement for biomedical applications. For example, in tissue engineering, a stiff multilayer coating, the presence of adhesion promoters, and/or bioactive molecules boost the adhesion, growth, and differentiation of cells. On the contrary, antimicrobial coatings should repel and inhibit the growth of bacteria. In drug delivery applications, mainly focused on particles and capsules at the micro- and nano-meter scale, the stability of the multilayer film is crucial in terms of retention and controlled release of the payload. Recent advances have shown the key role of the polypeptides in the adsorption of genetic material with high loading efficiency, and in addressing different pathways of the particles/capsules during the intracellular uptake, paving the way for applications in personalized medicine. Although there are a few studies, the responsiveness of the polypeptides to the pH changes, together with the inclusion of stimuli-responsive entities into the multilayer network, represents a further key factor for the development of smart drug delivery systems to promote a sustained release of therapeutics. The degradability of polypeptides may be an obstacle in certain scenarios for the controlled intracellular release of a drug once an external stimulus is applied. Nowadays, the highly engineered design of biodegradable LbL particles/capsules is oriented on the development of theranostics that, limited to use of polypeptides, are still in their infancy.

Current advance of nanotechnology in diagnosis and treatment for malignant tumors

Cancer remains a significant risk to human health. Nanomedicine is a new multidisciplinary field that is garnering a lot of interest and investigation. Nanomedicine shows great potential for cancer diagnosis and treatment. Specifically engineered nanoparticles can be employed as contrast agents in cancer diagnostics to enable high sensitivity and high-resolution tumor detection by imaging examinations. Novel approaches for tumor labeling and detection are also made possible by the use of nanoprobes and nanobiosensors. The achievement of targeted medication delivery in cancer therapy can be accomplished through the rational design and manufacture of nanodrug carriers. Nanoparticles have the capability to effectively transport medications or gene fragments to tumor tissues via passive or active targeting processes, thus enhancing treatment outcomes while minimizing harm to healthy tissues. Simultaneously, nanoparticles can be employed in the context of radiation sensitization and photothermal therapy to enhance the therapeutic efficacy of malignant tumors. This review presents a literature overview and summary of how nanotechnology is used in the diagnosis and treatment of malignant tumors. According to oncological diseases originating from different systems of the body and combining the pathophysiological features of cancers at different sites, we review the most recent developments in nanotechnology applications. Finally, we briefly discuss the prospects and challenges of nanotechnology in cancer.

pH-responsive self-assembled nanoparticles for tumor-targeted drug delivery

Recent advances in the field of drug delivery have opened new avenues for the development of novel nanodrug delivery systems (NDDS) in cancer therapy. Self-assembled nanoparticles (SANPs) based on tumour microenvironment have great advantages in improving antitumor effect, and pH-responsive SANPs prepared by the combination of pH-responsive nanomaterials and self-assembly technology can effectively improve the efficacy and reduce the systemic toxicity of antitumor drugs. In this review, we describe the characteristics of self-assembly and its driving force, the mechanism of pH-responsive NDDS, and the nanomaterials for pH-responsive SANPs type. A series of pH-responsive SANPs for tumour-targeted drug delivery are discussed, with an emphasis on the relation between structural features and theranostic performance.

HER2 siRNA Facilitated Gene Silencing Coupled with Doxorubicin Delivery: A Dual Responsive Nanoplatform Abrogates Breast Cancer

The present study investigated the concurrent delivery of antineoplastic drug, doxorubicin, and HER2 siRNA through a targeted theranostic metallic gold nanoparticle designed using polysaccharide, PSP001. The as-synthesized HsiRNA@PGD NPs were characterized in terms of structural, functional, physicochemical, and biological properties. HsiRNA@PGD NPs exposed adequate hydrodynamic size, considerable ζ potential, and excellent drug/siRNA loading and encapsulation efficiency. Meticulous exploration of the biocompatible dual-targeted nanoconjugate exhibited an appealing biocompatibility and pH-sensitive cargo release kinetics, indicating its safety for use in clinics. HsiRNA@PGD NPs deciphered competent cancer cell internalization, enhanced cytotoxicity mediated via the induction of apoptosis, and excellent downregulation of the overexpressing target HER2 gene. Further in vivo explorations in the SKBR3 xenograft breast tumor model revealed the appealing tumor reduction properties, selective accumulation in the tumor site followed by significant suppression of the HER2 gene which contributed to the exclusive abrogation of breast tumor mass by the HsiRNA@PGD NPs. Compared to free drugs or the monotherapy constructs, the dual delivery approach produced a synergistic suppression of breast tumors both in vitro and in vivo. Hence the drawings from these findings implicate that the as-synthesized HsiRNA@PGD NPs could offer a promising platform for chemo-RNAi combinational breast cancer therapy.

Recent Advances in Engineering Carriers for siRNA Delivery

RNA interference (RNAi) technology has been a promising treatment strategy for combating intractable diseases. However, the applications of RNAi in clinical are hampered by extracellular and intracellular barriers. To overcome these barriers, various siRNA delivery systems have been developed in the past two decades. The first approved RNAi therapeutic, Patisiran (ONPATTRO) using lipids as the carrier, for the treatment of amyloidosis is one of the most important milestones. This has greatly encouraged researchers to work on creating new functional siRNA carriers. In this review, the recent advances in siRNA carriers consisting of lipids, polymers, and polymer-modified inorganic particles for cancer therapy are summarized. Representative examples are presented to show the structural design of the carriers in order to overcome the delivery hurdles associated with RNAi therapies. Finally, the existing challenges and future perspective for developing RNAi as a clinical modality will be discussed and proposed. It is believed that the addressed contributions in this review will promote the development of siRNA delivery systems for future clinical applications.

Liposome bilayer stability: emphasis on cholesterol and its alternatives

Liposomes are spherical lipidic nanocarriers composed of natural or synthetic phospholipids with a hydrophobic bilayer and aqueous core, which are arranged into a polar head and a long hydrophobic tail, forming an amphipathic nano/micro-particle. Despite numerous liposomal applications, their use encounters many challenges related to the physicochemical properties strongly affected by their constituents, colloidal stability, and interactions with the biological environment. This review aims to provide a perspective and a clear idea about the main factors that regulate the liposomes' colloidal and bilayer stability, emphasising the roles of cholesterol and its possible alternatives. Moreover, this review will analyse strategies that offer possible approaches to provide more stable in vitro and in vivo liposomes with enhanced drug release and encapsulation efficiencies.

Fabrication of magnetic niosomal platform for delivery of resveratrol: potential anticancer activity against human pancreatic cancer Capan-1 cell

Recently, the presence of different nanoparticles (NPs) has developed targeting drug delivery in treatment of cancer cell. Targeted drug delivery systems using NPs have shown great promise in improving the efficacy of intracellular uptake as well as local concentration of therapeutics with minimizing side effects. The current study planned to synthesized resveratrol-loaded magnetic niosomes nanoparticles (RSV-MNIONPs) and evaluate their cytotoxicity activity in pancreatic cancer cells. For this aim, magnetic nanoparticles (MNPs) were synthesized and loaded into niosomes (NIOs) by the thin film hydration technique and then characterized via DLS, FT-IR, TEM, SEM and VSM techniques. Moreover, the cytotoxic activity of the RSV-MNIONPs on the Capan-1 cells line was assessed by the MTT test. The distribution number of RSV-MNIONPs was gained about 80 nm and 95 nm with surface charge of - 14.0 mV by SEM and TEM analysis, respectively. RSV loading efficacy in NIOs was about 85%, and the drug releases pattern displayed a sustained discharge with a maximum amount about 35% and 40%, within 4 h in pH = 7.4 and pH = 5.8, respectively. The cytotoxicity of the RSV-MNIONPs in the presence of an external magnetic field is higher than that of the RSV, indicating enhanced cellular uptake in their encapsulated states. Furthermore, RSV loaded MNNPs were found to induce more cell cycle arrest at the G0/G1 checkpoint than free RSV. Compared with RSV-treated cells, the mRNA expression levels of BAX, Bcl2, FAS, P 53, Cyclin D and hTERT, were significantly changed in cells treated with RSV loaded MNNPs. The niosomes NPs approaches have been widely used to attain higher solubility, improved bioavailability, enhanced stability, and control delivery of RSV. Our formulation displayed antitumor activity and can be considered an appropriate carrier with a great potential for future usage in cancer therapy.

Bioinspired Spatiotemporal Management toward RNA Therapies

Ribonucleic acid (RNA)-based therapies have become an attractive topic in disease intervention, especially with some that have been approved by the FDA such as the mRNA COVID-19 vaccine (Comirnaty, Pfizer-BioNTech, and Spikevax, Moderna) and Patisiran (siRNA-based drug for liver delivery). However, extensive applications are still facing challenges in delivering highly negatively charged RNA to the targeted site. Therapeutic delivery strategies including RNA modifications, RNA conjugates, and RNA polyplexes and delivery platforms such as viral vectors, nanoparticle-based delivery platforms, and hydrogel-based delivery platforms as potential nucleic acid-releasing depots have been developed to enhance their cellular uptake and protect nucleic acid from being degraded by immune systems. Here, we review the growing number of viral vectors, nanoparticles, and hydrogel-based RNA delivery systems; describe RNA loading/release mechanism induced by environmental stimulations including light, heat, pH, or enzyme; discuss their physical or chemical interactions; and summarize the RNA therapeutics release period (temporal) and their target cells/organs (spatial). Finally, we describe current concerns, highlight current challenges and future perspectives of RNA-based delivery systems, and provide some possible research areas that provide opportunities for clinical translation of RNA delivery carriers.

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.

Recent advances of polymeric nanoplatforms for cancer treatment: smart delivery systems (SDS), nanotheranostics and multidrug resistance (MDR) inhibition

Nanotheranostics is a promising field that combines the benefits of diagnostic and treatment into a single nano-platform that not only administers treatment but also allows for real-time monitoring of therapeutic response, decreasing the possibility of under/over-drug dosing. Furthermore, developing smart delivery systems (SDSs) for cancer theranostics that can take advantage of various tumour microenvironment (TME) conditions (such as deformed tumour vasculature, various over-expressed receptor proteins, reduced pH, oxidative stress, and resulting elevated glutathione levels) can aid in achieving improved pharmacokinetics, higher tumour accumulation, enhanced antitumour efficacy, and/or decreased side effects and multidrug resistance (MDR) inhibition. Polymeric nanoparticles (PNPs) are being widely investigated in this regard due to their unique features such as small size, passive/active targeting possibility, better pharmaceutical kinetics and biological distribution, decreased adverse reactions of the established drugs, inherent inhibitory properties to MDR efflux pump proteins, as well as the feasibility of delivering numerous therapeutic substances in just one design. Hence in this review, we have primarily discussed PNPs based targeted and/or controlled SDSs in which we have elaborated upon different TME mediated nanotheranostic platforms (NTPs) including active/passive/magnetic targeting platforms along with pH/ROS/redox-responsive platforms. Besides, we have elucidated different imaging guided cancer therapeutic platforms based on four major cancer imaging techniques i.e., fluorescence/photo-acoustic/radionuclide/magnetic resonance imaging, Furthermore, we have deliberated some of the most recently developed PNPs based multimodal NTPs (by combining two or more imaging or therapy techniques on a single nanoplatform) in cancer theranostics. Moreover, we have provided a brief update on PNPs based NTP which are recently developed to overcome MDR for effective cancer treatment. Additionally, we have briefly discussed about the tissue biodistribution/tumour targeting efficiency of these nanoplatforms along with recent preclinical/clinical studies. Finally, we have elaborated on various limitations associated with PNPs based nanoplatforms.

Exploring the outer limits of polyplexes

Histidine-containing polymers show promise in their transport of nucleic acids in vitro and in vivo. In addition to the pH-buffering histidine component, the polymer often contains a protonated component at physiological pH, such as lysine. These polyplexes usually accumulate in the tumor by enhanced permeability and retention, which has proved disappointing in clinical trials. We presently compare two histidine-lysine (HK) peptide polyplexes for their neuropilin-1-mediated transport of plasmids in vivo. While the polymerized HK (H2KC-48) polyplex was markedly better than the monomeric HK (H2K) polyplex in vitro, both HK polyplexes were effective in transfecting tumor xenografts over a wide range of peptide and plasmid ratios. Nevertheless, polyplexes of low peptide/DNA ratios gave higher tumor transfection and specificity than those of higher ratios. Surprisingly, there was minimal to no gel retardation of polyplexes made from these low ratios during electrophoresis. These results demonstrate that loosely packed HK polyplexes effectively transfected tumors in vivo.

pH-triggered "PEG" sheddable and folic acid-targeted nanoparticles for docetaxel delivery in breast cancer treatment

Multifunctional nanoparticles have attracted significant attentions for oncology and cancer treatment. In fact, they could address critical point for tumour treatment by creating a stimuli-responsive targeted drug delivery system that can exist stably in the systemic circulation, efficiently penetrate the tumour tissue, and then accumulate in tumour cells in large quantities. A novel stepwise pH-responsive multifunctional nanoparticles (FPDPCNPs/DTX) for targeted delivery of the antitumour drug docetaxel (DTX) is prepared by coating a tumour acidity-sensitive "sheddable" FA modified β-carboxylic amide functionalized PEG layer (folic acid-polyethylene glycol-2,3-dimethylmaleic anhydride, FA-PEG-DA) on the cationic drug-loaded core (poly(β-amino ester-cholesterol, PAE-Chol) through electrostatic interaction in this study. The charge shielding behaviour of the FPDPCNPs/DTX was confirmed by zeta potential assay. The surface charges of the nanoparticles can change from positive to negative after PEG coating. The IC50 values of FPDPCNPs/DTX was 3.04 times higher than that of PEG "unsheddable" nanoparticles in cytotoxicity experiments. The results of in vivo experiment further showed that FPDPCNPs/DTX had enhanced tumour targeting effect, the tumour inhibition rate of FPDPCNPs/DTX was as high as 81.99%, which was 1.51 times that of free DTX. Under a micro acidic environment and folate receptor (FR)-mediated targeting, FPDPCNPs/DTX contributed to more uptake of DTX by MCF-7 cells. In summary, FPDPCNPs/DTX as a multifunctional nano-drug delivery system provides a promising strategy for efficiently delivering antitumour drugs.

Gold Nanoparticles: Construction for Drug Delivery and Application in Cancer Immunotherapy

Cancer immunotherapy is an innovative treatment strategy to enhance the ability of the immune system to recognize and eliminate cancer cells. However, dose limitations, low response rates, and adverse immune events pose significant challenges. To address these limitations, gold nanoparticles (AuNPs) have been explored as immunotherapeutic drug carriers owing to their stability, surface versatility, and excellent optical properties. This review provides an overview of the advanced synthesis routes for AuNPs and their utilization as drug carriers to improve precision therapies. The review also emphasises various aspects of AuNP-based immunotherapy, including drug loading, targeting strategies, and drug release mechanisms. The application of AuNPs combined with cancer immunotherapy and their therapeutic efficacy are briefly discussed. Overall, we aimed to provide a recent understanding of the advances, challenges, and prospects of AuNPs for anticancer applications.

Advancements in pH-responsive nanocarriers: enhancing drug delivery for tumor therapy

INTRODUCTION

Tumors pose a significant global economic and health burden, with conventional cancer treatments lacking tumor specificity, leading to limited efficiency and undesirable side effects. Targeted tumor therapy is imminent. Tumor cells produce lactate and hydrogen ions (H+) by Warburg effect, forming an acidic tumor microenvironment (TME), which can be employed to design targeted tumor therapy. Recently, progress in nanotechnology has led to the development of pH-responsive nanocarriers, which have gathered significant attention. Under acidic tumor conditions, they exhibit targeted accumulation within tumor sites and controlled release profiles of therapeutic reagents, enabling precise tumor therapy.

AREAS COVERED

This review comprehensively summarize the principles underlying pH-responsive features, discussing various types of pH-responsive nanocarriers, their advantages, and limitations. Innovative therapeutic drugs are also examined, followed by an exploration of recent advancements in applying various pH-responsive nanocarriers as delivery systems for enhanced tumor therapy.

EXPERT OPINIONS

pH-responsive nanocarriers have garnered significant attention for their capability to achieve targeted accumulation of therapeutic agents at tumor sites and controlled drug delivery profiles, ultimately increasing the efficiency of tumor eradication. It is anticipated that the employment of pH-responsive nanocarriers will elevate the effectiveness and safety of tumor therapy, contributing to improved overall outcomes.

Targeted delivery of silibinin via magnetic niosomal nanoparticles: potential application in treatment of colon cancer cells

Introduction: In recent years, various nanoparticles (NPs) have been discovered and synthesized for the targeted therapy of cancer cells. Targeted delivery increases the local concentration of therapeutics and minimizes side effects. Therefore, NPs-mediated targeted drug delivery systems have become a promising approach for the treatment of various cancers. As a result, in the current study, we aimed to design silibinin-loaded magnetic niosomes nanoparticles (MNNPs) and investigate their cytotoxicity property in colorectal cancer cell treatment. Methods: MNPs ferrofluids were prepared and encapsulated into niosomes (NIOs) by the thin film hydration method. Afterward, the morphology, size, and chemical structure of the synthesized MNNPs were evaluated using the TEM, DLS, and FT-IR techniques, respectively. Results and Discussion: The distribution number of MNNPs was obtained at about 50 nm and 70 nm with a surface charge of -19.0 mV by TEM and DLS analysis, respectively. Silibinin loading efficiency in NIOs was about 90%, and the drug release pattern showed a controlled release with a maximum amount of about 49% and 70%, within 4 h in pH = 7.4 and pH = 5.8, respectively. To investigate the cytotoxicity effect, HT-29 cells were treated with the various concentration of the drugs for 24 and 48 h and evaluated by the MTT as well as flow cytometry assays. Obtained results demonstrated promoted cell cytotoxicity of silibinin-loaded MNNPs (5-fold decrease in cell viability) compared to pure silibinin (3-fold decrease in cell viability) while had no significant cytotoxic effect on HEK-293 (normal cell line) cells, and the cellular uptake level of MNNPs by the HT-29 cell line was enhanced compared to the control group. In conclusion, silibinin-loaded MNNPs complex can be considered as an efficient treatment approach for colorectal cancer cells.

Delivery of Chemotherapy Agents and Nucleic Acids with pH-Dependent Nanoparticles

With less than one percent of systemically injected nanoparticles accumulating in tumors, several novel approaches have been spurred to direct and release the therapy in or near tumors. One such approach depends on the acidic pH of the extracellular matrix and endosomes of the tumor. With an average pH of 6.8, the extracellular tumor matrix provides a gradient for pH-responsive particles to accumulate, enabling greater specificity. Upon uptake by tumor cells, nanoparticles are further exposed to lower pHs, reaching a pH of 5 in late endosomes. Based on these two acidic environments in the tumor, various pH-dependent targeting strategies have been employed to release chemotherapy or the combination of chemotherapy and nucleic acids from macromolecules such as the keratin protein or polymeric nanoparticles. We will review these release strategies, including pH-sensitive linkages between the carrier and hydrophobic chemotherapy agent, the protonation and disruption of polymeric nanoparticles, an amalgam of these first two approaches, and the release of polymers shielding drug-loaded nanoparticles. While several pH-sensitive strategies have demonstrated marked antitumor efficacy in preclinical trials, many studies are early in their development with several obstacles that may limit their clinical use.

"Smart" drug delivery: A window to future of translational medicine

Chemotherapy is the mainstay of cancer treatment today. Chemotherapeutic drugs are non-selective and can harm both cancer and healthy cells, causing a variety of adverse effects such as lack of specificity, cytotoxicity, short half-life, poor solubility, multidrug resistance, and acquiring cancer stem-like characteristics. There is a paradigm shift in drug delivery systems (DDS) with the advent of smarter ways of targeted cancer treatment. Smart Drug Delivery Systems (SDDSs) are stimuli responsive and can be modified in chemical structure in response to light, pH, redox, magnetic fields, and enzyme degradation can be future of translational medicine. Therefore, SDDSs have the potential to be used as a viable cancer treatment alternative to traditional chemotherapy. This review focuses mostly on stimuli responsive drug delivery, inorganic nanocarriers (Carbon nanotubes, gold nanoparticles, Meso-porous silica nanoparticles, quantum dots etc.), organic nanocarriers (Dendrimers, liposomes, micelles), antibody-drug conjugates (ADC) and small molecule drug conjugates (SMDC) based SDDSs for targeted cancer therapy and strategies of targeted drug delivery systems in cancer cells.

An Overview of Polymeric Nanoparticles-Based Drug Delivery System in Cancer Treatment

Cancer is recognized as one of the world's deadliest diseases, with more than 10 million new cases each year. Over the past 2 decades, several studies have been performed on cancer to pursue solutions for effective treatment. One of the vital benefits of utilizing nanoparticles (NPs) in cancer treatment is their high adaptability for modification and amalgamation of different physicochemical properties to boost their anti-cancer activity. Various nanomaterials have been designed as nanocarriers attributing nontoxic and biocompatible drug delivery systems with improved bioactivity. The present review article briefly explained various types of nanocarriers, such as organic-inorganic-hybrid NPs, and their targeting mechanisms. Here a special focus is given to the synthesis, benefits, and applications of polymeric NPs (PNPs) involved in various anti-cancer therapeutics. It has also been discussed about the drug delivery approach by the functionalized/encapsulated PNPs (without/with targeting ability) that are being applied in the therapy and diagnostic (theranostics). Overall, this review can give a glimpse into every aspect of PNPs, from their synthesis to drug delivery application for cancer cells.

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.

Smart Polymeric Micelles for Anticancer Hydrophobic Drugs

Cancer has become one of the deadliest diseases in our society. Surgery accompanied by subsequent chemotherapy is the treatment most used to prolong or save the patient's life. Still, it carries secondary risks such as infections and thrombosis and causes cytotoxic effects in healthy tissues. Using nanocarriers such as smart polymer micelles is a promising alternative to avoid or minimize these problems. These nanostructured systems will be able to encapsulate hydrophilic and hydrophobic drugs through modified copolymers with various functional groups such as carboxyls, amines, hydroxyls, etc. The release of the drug occurs due to the structural degradation of these copolymers when they are subjected to endogenous (pH, redox reactions, and enzymatic activity) and exogenous (temperature, ultrasound, light, magnetic and electric field) stimuli. We did a systematic review of the efficacy of smart polymeric micelles as nanocarriers for anticancer drugs (doxorubicin, paclitaxel, docetaxel, lapatinib, cisplatin, adriamycin, and curcumin). For this reason, we evaluate the influence of the synthesis methods and the physicochemical properties of these systems that subsequently allow an effective encapsulation and release of the drug. On the other hand, we demonstrate how computational chemistry will enable us to guide and optimize the design of these micelles to carry out better experimental work.

Nanoparticles design considerations to co-deliver nucleic acids and anti-cancer drugs for chemoresistance reversal

Chemoresistance and hence the consequent treatment failure is considerably challenging in clinical cancer therapeutics. The understanding of the genetic variations in chemoresistance acquisition encouraged the use of gene modulatory approaches to restore anti-cancer drug efficacy. Many smart nanoparticles are designed and optimized to mediate combinational therapy between nucleic acid and anti-cancer drugs. This review aims to define a rational design of such co-loaded nanocarriers with the aim of chemoresistance reversal at various cellular levels to improve the therapeutic outcome of anticancer treatment. Going through the principles of therapeutics loading, physicochemical characteristics tuning, and different nanocarrier modifications, also looking at combination effectiveness on chemosensitivity restoration. Up to now, these emerging nanocarriers are in development status but are expected to introduce outstanding outcomes.

pH-Sensitive Targeting of Tumors with Chemotherapy-Laden Nanoparticles: Progress and Challenges

Accumulating chemotherapeutic drugs such as doxorubicin within a tumor while limiting the drug dose to normal tissues is a central goal of drug delivery with nanoparticles. Liposomal products such as Doxil® represent one of the marked successes of nanoparticle-based strategies. To replicate this success for cancer treatment, many approaches with nanoparticles are being explored in order to direct and release chemotherapeutic agents to achieve higher accumulation in tumors. A promising approach has been stimulus-based therapy, such as the release of chemotherapeutic agents from the nanoparticles in the acidic environments of the tumor matrix or the tumor endosomes. Upon reaching the acidic environments of the tumor, the particles, which are made up of pH-dependent polymers, become charged and release the entrapped chemotherapy agents. This review discusses recent advances in and prospects for pH-dependent histidine-based nanoparticles that deliver chemotherapeutic agents to tumors. The strategies used by investigators include an array of histidine-containing peptides and polymers which form micelles, mixed micelles, nanovesicles, polyplexes, and coat particles. To date, several promising histidine-based nanoparticles have been demonstrated to produce marked inhibition of tumor growth, but challenges remain for successful outcomes in clinical trials. The lessons learned from these histidine-containing particles will provide insight in the development of improved pH-dependent polymeric delivery systems for chemotherapy.

Current Advancements in Self-assembling Nanocarriers-Based siRNA Delivery for Cancer Therapy

Different therapeutic practices for treating cancers have significantly evolved to compensate and/or overcome the failures in conventional methodologies. The demonstrated potentiality in completely inhibiting the tumors and in preventing cancer relapse has made nucleic acids therapy (NAT)/gene therapy as an attractive practice. This has been made possible because NAT-based cancer treatments are highly focused on the fundamental mechanisms - i.e., silencing the expression of oncogenic genes responsible for producing abnormal proteins (via messenger RNAs (mRNAs)). However, the future clinical translation of NAT is majorly dependent upon the effective delivery of the exogenous nucleic acids (especially RNAs - e.g., short interfering RNAs (siRNAs) - herein called biological drugs). Moreover, nano-based vehicles (i.e., nanocarriers) are involved in delivering them to prevent degradation and undesired bioaccumulation while enhancing the stability of siRNAs. Herein, we have initially discussed about three major types of self-assembling nanocarriers (liposomes, polymeric nanoparticles and exosomes). Later, we have majorly reviewed recent developments in non-targeted/targeted nanocarriers for delivery of biological drugs (individual/dual) to silence the most important genes/mRNAs accountable for inducing protein abnormality. These proteins include polo-like kinase 1 (PLK1), survivin, vascular endothelial growth factor (VEGF), B-cell lymphoma/leukaemia-2 (Bcl-2) and multi-drug resistance (MDR). Besides, the consequent therapeutic effects on cancer growth, invasion and/or metastasis have also been discussed. Finally, we have comprehensively reviewed the improvements achieved in the cutting-edge cancer therapeutics while delivering siRNAs in combination with clinically approved chemotherapeutic drugs.

Synthesis, characterization, and evaluation of in vitro cytotoxicity and in vivo antitumor activity of asiatic acid-loaded poly lactic-co-glycolic acid nanoparticles: A strategy of treating breast cancer

Asiatic acid (AA), an aglycone of pentacyclic triterpene glycoside, obtained from the leaves of Centella asiatica exerts anticancer effects by inhibiting cellular proliferation and inducing apoptosis in a wide range of carcinogenic distresses. However, its chemotherapeutic efficacy is dampened by its low bioavailability. Polymeric nanoparticles (NPs) exhibit therapeutic efficacy and compliance by improving tissue penetration and lowering toxicity. Thus, to increase the therapeutic effectiveness of AA in the treatment of breast cancer, AA-loaded poly lactic-co-glycolic acid (PLGA) NPs (AA-PLGA NPs) have been formulated. The AA-PLGA NPs were characterized on the basis of their average particle size, zeta potential, electron microscopic imaging, drug loading, and entrapment efficiency. The NPs exhibited sustained drug release profile in vitro. Developed NPs exerted dose-dependent cytotoxicity to MCF-7 and MDA-MB-231 cells without damaging normal cells. The pro-oxidant and pro-apoptotic properties of AA-PLGA NPs were determined by the study of the cellular levels of SOD, CAT, GSH-GSSG, MDA, protein carbonylation, ROS, mitochondrial membrane potential, and FACS analyses on MCF-7 cells. Immunoblotting showed that AA-PLGA NPs elicited an intrinsic pathway of apoptosis in MCF-7 cells. In vivo studies on female BALB/c mice exhibited reduced volume of mammary pad tumor tissues and augmented expression of caspase-3 when administered with AA-PLGA NPs. No systemic adverse effect of AA-PLGA NPs was observed in our studies. Thus, AA-PLGA NPs can act as an efficient drug delivery system against breast cancer.

Recent Advances in Nanoparticle-Based Co-Delivery Systems for Cancer Therapy

Cancer therapies have advanced tremendously throughout the last decade, yet multiple factors still hinder the success of the different cancer therapeutics. The traditional therapeutic approach has been proven insufficient and lacking in the suppression of tumor growth. The simultaneous delivery of multiple small-molecule chemotherapeutic drugs and genes improves the effectiveness of each treatment, thus optimizing efficacy and improving synergistic effects. Nanomedicines integrating inorganic, lipid, and polymeric-based nanoparticles have been designed to regulate the spatiotemporal release of the encapsulated drugs. Multidrug-loaded nanocarriers are a potential strategy to fight cancer and the incorporation of co-delivery systems as a feasible treatment method has projected synergistic benefits and limited undesirable effects. Moreover, the development of co-delivery systems for maximum therapeutic impact necessitates better knowledge of the appropriate therapeutic agent ratio as well as the inherent heterogeneity of the cancer cells. Co-delivery systems can simplify clinical processes and increase patient quality of life, even though such systems are more difficult to prepare than single drug delivery systems. This review highlights the progress attained in the development and design of nano carrier-based co-delivery systems and discusses the limitations, challenges, and future perspectives in the design and fabrication of co-delivery systems.

Encapsulation of miRNA and siRNA into Nanomaterials for Cancer Therapeutics

Globally, cancer is amongst the most deadly diseases due to the low efficiency of the conventional and obsolete chemotherapeutic methodologies and their many downsides. The poor aqueous solubility of most anticancer medications and their low biocompatibility make them ineligible candidates for the design of delivery systems. A significant drawback associated with chemotherapy is that there are no advanced solutions to multidrug resistance, which poses a major obstacle in cancer management. Since RNA interference (RNAi) can repress the expression of genes, it is viewed as a novel tool for advanced drug delivery. this is being explored as a promising drug targeting strategy for the treatment of multiple diseases, including cancer. However, there are many obstructions that hinder the clinical uses of siRNA drugs due to their low permeation into cells, off-target impacts, and possible unwanted immune responses under physiological circumstances. Thus, in this article, we review the design measures for siRNA conveyance frameworks and potential siRNA and miRNA drug delivery systems for malignant growth treatment, including the use of liposomes, dendrimers, and micelle-based nanovectors and functional polymer-drug delivery systems. This article sums up the advancements and challenges in the use of nanocarriers for siRNA delivery and remarkably centers around the most critical modification strategies for nanocarriers to build multifunctional siRNA and miRNA delivery vectors. In short, we hope this review will throw light on the dark areas of RNA interference, which will further open novel research arenas in the development of RNAi drugs for cancer.

Genetically engineered bacteria-mediated multi-functional nanoparticles for synergistic tumor-targeting therapy

Focused ultrasonic ablation surgery (FUAS) for tumor treatment has emerged as an effective non-invasive therapeutic approach, but its widespread clinical utilization is limited by its low therapeutic efficiency caused by inadequate tumor targeting, single imaging modality, and possible tumor recurrence following surgery. Therefore, this study aimed to develop a biological targeting synergistic system consisting of genetically engineered bacteria and multi-functional nanoparticles to overcome these limitations. Escherichia coli was genetically modified to carry an acoustic reporter gene encoding the formation of gas vesicles (GVs) and then target the tumor hypoxic environment in mice. After E. coli producing GVs (GVs-E. coli) colonized the tumor target area, ultrasound imaging and collaborative FUAS were performed; multi-functional nanoparticles were then enriched in the tumor target area through electrostatic adsorption. Multi-functional cationic lipid nanoparticles containing IR780, perfluorohexane, and banoxantrone dihydrochloride (AQ4N) were coloaded in the tumor to realize targeted multimodal imaging and enhance the curative effect of FUAS. AQ4N was stimulated by the tumor hypoxic environment and synergistically cooperated with FUAS to kill tumor cells. In sum, synergistic tumor therapy involving multi-functional nanoparticles mediated by genetically engineered bacteria overcomes the limitations and improves the curative effect of existing FUAS. STATEMENT OF SIGNIFICANCE: Inadequate tumor targeting, single image monitoring mode, and prone tumor recurrence following surgery remain significant challenges yet critical for tumor therapy. This study proposes a strategy for genetically engineered bacteria-mediated multifunctional nanoparticles for synergistic tumor therapy. The multifunctional genetically engineered biological targeting synergistic agent can accomplish tumor-targeting therapy, synergistic FUAS ablation, hypoxia-activated chemotherapy combined with FUAS ablation, and multiple-imaging guidance and monitoring all at the same time, thereby compensating for the shortcomings of FUAS treatment. This strategy could pave the way for the progress of tumor therapy.

Nanocarriers: A Reliable Tool for the Delivery of Anticancer Drugs

Nanomedicines have gained popularity due to their potential therapeutic applications, especially cancer treatment. Targeted nanoparticles can deliver drugs directly to cancer cells and enable prolonged drug release, reducing off-target toxicity and increasing therapeutic efficacy. However, translating nanomedicines from preclinical to clinical settings has been difficult. Rapid advancements in nanotechnology promise to enhance cancer therapies. Nanomedicine offers advanced targeting and multifunctionality. Nanoparticles (NPs) have several uses nowadays. They have been studied as drug transporters, tumor gene delivery agents, and imaging contrast agents. Nanomaterials based on organic, inorganic, lipid, or glycan substances and synthetic polymers have been used to enhance cancer therapies. This review focuses on polymeric nanoparticle delivery strategies for anticancer nanomedicines.

US/MR Bimodal Imaging-Guided Bio-Targeting Synergistic Agent for Tumor Therapy

Purpose

Breast cancer is detrimental to the health of women due to the difficulty of early diagnosis and unsatisfactory therapeutic efficacy of available breast cancer therapies. High intensity focused ultrasound (HIFU) ablation is a new method for the treatment of breast tumors, but there is a problem of low ablation efficiency. Therefore, the improvement of HIFU efficiency to combat breast cancer is immediately needed. This study aimed to describe a novel anaerobic bacteria-mediated nanoplatform, comprising synergistic HIFU therapy for breast cancer under guidance of ultrasound (US) and magnetic resonance (MR) bimodal imaging.

Methods

The PFH@CL/Fe₃O₄ nanoparticles (NPs) (Perfluorohexane (PFH) and superparamagnetic iron oxides (SPIO, Fe₃O₄) with cationic lipid (CL) NPs) were synthesized using the thin membrane hydration method. The novel nanoplatform Bifidobacterium bifidum-mediated PFH@CL/Fe₃O₄ NPs were constructed by electrostatic adsorption. Thereafter, US and MR bimodal imaging ability of B. bifidum-mediated PFH@CL/Fe₃O₄ NPs was evaluated in vitro and in vivo. Finally, the efficacy of HIFU ablation based on B. bifidum-PFH@CL/Fe₃O₄ NPs was studied.

Results

B. bifidum combined with PFH@CL/Fe₃O₄ NPs by electrostatic adsorption and enhanced the tumor targeting ability of PFH@CL/Fe₃O₄ NPs. US and MR bimodal imaging clearly displayed the distribution of the bio-targeting nanoplatform in vivo. It was conducive for accurate and effective guidance of HIFU synergistic treatment of tumors. Furthermore, PFH@CL/Fe₃O₄ NPs could form microbubbles by acoustic droplet evaporation and promote efficiency of HIFU ablation under guidance of bimodal imaging.

Conclusion

A bio-targeting nanoplatform with high stability and good physicochemical properties was constructed. The HIFU synergistic agent achieved early precision imaging of tumors and promoted therapeutic effect, monitored by US and MR bimodal imaging during the treatment process.

Co-Delivery of Repurposing Itraconazole and VEGF siRNA by Composite Nanoparticulate System for Collaborative Anti-Angiogenesis and Anti-Tumor Efficacy against Breast Cancer

Combinations of two different therapeutic modalities of VEGF inhibitors against angiogenesis can cooperatively impede breast cancer tumor growth and enhance therapeutic efficacy. Itraconazole (ITZ) is a conventional antifungal drug with high safety; however, it has been repurposed to be a multi target anti-angiogenesis agent for cancer therapy in recent years. In the present study, composite nanoparticles co-loaded with ITZ and VEGF siRNA were prepared in order to investigate their anti-angiogenesis efficacy and synergistic anticancer effect against breast cancer. The nanoparticles had a suitable particle size (117.9 ± 10.3 nm) and weak positive surface charge (6.69 ± 2.46 mV), as well as good stability and drug release profile in vitro. Moreover, the nanoparticles successfully escaped from endosomes and realized cell apoptosis and cell proliferation inhibition in vitro. In vitro and in vivo experiments showed that the nanoparticles could induce the silencing of VEGF-related expressions as well as anti-angiogenesis efficacy, and the co-loaded ITZ-VEGF siRNA NPs could inhibit tumor growth effectively with low toxicity and side effects. Taken together, the as-prepared delivery vehicles are a simple and safe nano-platform that improves the antitumor efficacy of VEGF siRNA and ITZ, which allows the repositioning of the generic drug ITZ as a great candidate for antitumor therapy.

Development and Evaluation of a PSMA-Targeted Nanosystem Co-Packaging Docetaxel and Androgen Receptor siRNA for Castration-Resistant Prostate Cancer Treatment

Primary prostate cancer (PC) progresses to castration-resistant PC (CRPC) during androgen deprivation therapy (ADR) in early stages of prostate cancer. Thus, rather than blocking the androgen-related pathway further, docetaxel (DTX)-based therapy has become the most effective and standard first-line chemotherapy for CRPC. Although the therapy is successful in prolonging the survival of patients with CRPC, chemotherapy resistance develops due to the abnormal activation of the androgen receptor (AR) signaling pathway. Thus, to optimize DTX efficacy, continued maximum suppression of androgen levels and AR signaling is required. Here, we designed a prostate-specific membrane antigen (PSMA)-targeted nanosystem to carry both DTX and AR siRNA (Di-PP/AR-siRNA/DTX) for CRPC treatment. Specifically, DTX was encapsulated into the hydrophobic inner layer, and the AR siRNA was then condensed with the cationic PEI block in the hydrophilic outer layer of the PEI-PLGA polymeric micelles. The micelles were further coated with PSMA-targeted anionic polyethylene glycol-polyaspartic acid (Di-PEG-PLD). In vitro and in vivo results demonstrated that the resulting Di-PP/AR-siRNA/DTX exhibited prolonged blood circulation, selective targeting, and enhanced antitumor effects. Consequently, Di-PP/AR-siRNA/DTX holds great potential for efficient CRPC treatment by combining chemotherapy and siRNA silencing of androgen-related signaling pathways.

Noncoding RNAs and their therapeutics in paclitaxel chemotherapy: Mechanisms of initiation, progression, and drug sensitivity

The identification of agents that can reverse drug resistance in cancer chemotherapy, and enhance the overall efficacy is of great interest. Paclitaxel (PTX) belongs to taxane family that exerts an antitumor effect by stabilizing microtubules and inhibiting cell cycle progression. However, PTX resistance often develops in tumors due to the overexpression of drug transporters and tumor-promoting pathways. Noncoding RNAs (ncRNAs) are modulators of many processes in cancer cells, such as apoptosis, migration, differentiation, and angiogenesis. In the present study, we summarize the effects of ncRNAs on PTX chemotherapy. MicroRNAs (miRNAs) can have opposite effects on PTX resistance (stimulation or inhibition) via influencing YES1, SK2, MRP1, and STAT3. Moreover, miRNAs modulate the growth and migration rates of tumor cells in regulating PTX efficacy. PIWI-interacting RNAs, small interfering RNAs, and short-hairpin RNAs are other members of ncRNAs regulating PTX sensitivity of cancer cells. Long noncoding RNAs (LncRNAs) are similar to miRNAs and can modulate PTX resistance/sensitivity by their influence on miRNAs and drug efflux transport. The cytotoxicity of PTX against tumor cells can also be affected by circular RNAs (circRNAs) and limitation is that oncogenic circRNAs have been emphasized and experiments should also focus on onco-suppressor circRNAs.

Application of "smart" multifunctional nanoprobes in tumor diagnosis and treatment

Cancer is one of the major diseases that pose a threat to human health and life, especially because it is difficult to diagnose and cure, and recurs easily. In recent years, the development of nanotechnology has provided researchers with new tools for cancer treatment. In particular, nanoprobes that facilitate integrated diagnosis and treatment, high-resolution imaging, and accurate tumor targeting provide new avenues for the early detection and treatment of cancer. This review focuses on the preparations and applications of two kinds of "smart" multifunctional nanoprobes: "Off-On" nanoprobes and "Charge-Reversal" nanoprobes. This review also briefly discusses their mechanisms of action, as they could provide new ideas for the further development of this field.

Targeted Cancer Therapy via pH-Functionalized Nanoparticles: A Scoping Review of Methods and Outcomes

(1) Background: In recent years, several studies have described various and heterogenous methods to sensitize nanoparticles (NPs) to pH changes; therefore, in this current scoping review, we aimed to map current protocols for pH functionalization of NPs and analyze the outcomes of drug-loaded pH-functionalized NPs (pH-NPs) when delivered in vivo in tumoral tissue. (2) Methods: A systematic search of the PubMed database was performed for all published studies relating to in vivo models of anti-tumor drug delivery via pH-responsive NPs. Data on the type of NPs, the pH sensitization method, the in vivo model, the tumor cell line, the type and name of drug for targeted therapy, the type of in vivo imaging, and the method of delivery and outcomes were extracted in a separate database. (3) Results: One hundred and twenty eligible manuscripts were included. Interestingly, 45.8% of studies (n = 55) used polymers to construct nanoparticles, while others used other types, i.e., mesoporous silica (n = 15), metal (n = 8), lipids (n = 12), etc. The mean acidic pH value used in the current literature is 5.7. When exposed to in vitro acidic environment, without exception, pH-NPs released drugs inversely proportional to the pH value. pH-NPs showed an increase in tumor regression compared to controls, suggesting better targeted drug release. (4) Conclusions: pH-NPs were shown to improve drug delivery and enhance antitumoral effects in various experimental malignant cell lines.

TfR-T12 short peptide and pH sensitive cell transmembrane peptide modified nano-composite micelles for glioma treatment via remodeling tumor microenvironment

Two kinds of amphiphilic block copolymers of TfR-T12-PEG-PLGA and TATH7-PEG-PLGA were synthesized to self-assembly nano-composite micelles for encapsulating paclitaxel and imiquimod synchronously. TfR-T12 peptide modified nano-composite micelles can pass through BBB in a TfR-mediated way to achieve targeted delivery of chemotherapeutic drugs, and pH sensitive TATH7 peptide modified nano-composite micelles enhanced uptake efficiency more significantly under pH 5.5 medium than pH 7.4 medium. The results of pharmacodynamic evaluation in vivo showed that the nano-composite micelles had achieved good anti-tumor effect in subcutaneous and normotopia glioma models, and effectively prolonged the life cycle of tumor-bearing mice. The nano-composite micelles regulated the immunosuppression phenomenon of tumor microenvironment significantly, and promoted the M1 polarization of TAMs, then enhanced the proliferation and activation of CD8⁺ T cells in tumor microenvironment. It comes to conclusion that the nano-composite micelle achieves the purpose of effective treatment of glioma by chemotherapy combined with immunotherapy.

Size-Transformable Bicomponent Peptide Nanoparticles for Deep Tumor Penetration and Photo-Chemo Combined Antitumor Therapy

The suitable size of multifunctional nanomedicines strongly influences their physicochemical properties and actions in biological systems, for example, prolonged blood circulation time, efficient tumor accumulation, and deep tumor penetration. However, it is still a great challenge to construct size-transformable nanoparticles (NPs) for both efficient accumulation and penetration throughout tumor tissue. Herein, a size-transformed multifunctional NP is developed through a simple bicomponent assembling strategy for enhanced tumor penetration and efficient photo-chemo combined antitumor therapy, due to the acidic tumor microenvironment and near infrared-laser irradiation induced size-shrink. This multifunctional bicomponent NP (PP NP) driven by electrostatic interaction is composed of negatively charged peptide amphiphile (PA1) and positively charged peptide prodrug (PA2). PP NPs (≈170 nm) have been proven to improve blood circulation time and stability in biological environments. Interestingly, PP NPs can reassemble small NPs (<30 nm) by responding to acidic tumor microenvironment and near-infrared laser irradiation, which facilitates deep tumor penetration and improves cellular internalization. By integrating fluorescence imaging, tumor targeting, deep tumor penetration, and combined photo-chemotherapy, PP NPs exhibit excellent in vivo antitumor efficacy. This study might provide an insight for developing a bicomponent assembling system with efficient tumor penetration and multimode for antitumor therapy.

Ultrasmall Luminescent Metal Nanoparticles: Surface Engineering Strategies for Biological Targeting and Imaging

In the past decade, ultrasmall luminescent metal nanoparticles (ULMNPs, d < 3 nm) have achieved rapid progress in addressing many challenges in the healthcare field because of their excellent physicochemical properties and biological behaviors. With the sharp shrinking size of large plasmonic metal nanoparticles (PMNPs), the contributions from the surface characteristics increase significantly, which brings both opportunities and challenges in the application-driven surface engineering of ULMNPs toward advanced biological applications. Here, the systematic advancements in the biological applications of ULMNPs from bioimaging to theranostics are summarized with emphasis on the versatile surface engineering strategies in the regulation of biological targeting and imaging performance. The efforts in the surface functionalization strategies of ULMNPs for enhanced disease targeting abilities are first discussed. Thereafter, self-assembly strategies of ULMNPs for fabricating multifunctional nanostructures for multimodal imaging and nanomedicine are discussed. Further, surface engineering strategies of ratiometric ULMNPs to enhance the imaging stability to address the imaging challenges in complicated bioenvironments are summarized. Finally, the phototoxicity of ULMNPs and future perspectives are also reviewed, which are expected to provide a fundamental understanding of the physicochemical properties and biological behaviors of ULMNPs to accelerate their future clinical applications in healthcare.

Smart Nanotherapeutics and Lung Cancer

Lung cancer is a significant health problem worldwide. Unfortunately, current therapeutic strategies lack a sufficient level of specificity and can harm adjacent healthy cells. Consequently, to address the clinical need, novel approaches to improve treatment efficiency with minimal side effects are required. Nanotechnology can substantially contribute to the generation of differentiated products and improve patient outcomes. Evidence from previous research suggests that nanotechnology-based drug delivery systems could provide a promising platform for the targeted delivery of traditional chemotherapeutic drugs and novel small molecule therapeutic agents to treat lung cancer cells more effectively. This has also been found to improve the therapeutic index and reduce the required drug dose. Nanodrug delivery systems also provide precise control over drug release, resulting in reduced toxic side effects, controlled biodistribution, and accelerated effects or responses. This review highlights the most advanced and novel nanotechnology-based strategies, including targeted nanodrug delivery systems, stimuli-responsive nanoparticles, and bio-nanocarriers, which have recently been employed in preclinical and clinical investigations to overcome the current challenges in lung cancer treatments.