Preparation and characterization of paclitaxel palmitate albumin nanoparticles with high loading efficacy: an in vitro and in vivo anti-tumor study in mouse models

Albumin Nanoparticle-Based Drug Delivery Systems

Nanoparticle-based systems are extensively investigated for drug delivery. Among others, with superior biocompatibility and enhanced targeting capacity, albumin appears to be a promising carrier for drug delivery. Albumin nanoparticles are highly favored in many disease therapies, as they have the proper chemical groups for modification, cell-binding sites for cell adhesion, and affinity to protein drugs for nanocomplex generation. Herein, this review summarizes the recent fabrication techniques, modification strategies, and application of albumin nanoparticles. We first discuss various albumin nanoparticle fabrication methods, from both pros and cons. Then, we provide a comprehensive introduction to the modification section, including organic albumin nanoparticles, metal albumin nanoparticles, inorganic albumin nanoparticles, and albumin nanoparticle-based hybrids. We finally bring further perspectives on albumin nanoparticles used for various critical diseases.

Preparation of stable and monodisperse paclitaxel-loaded bovine serum albumin nanoparticles via intermolecular disulfide crosslinking

Paclitaxel (PTX) is one of the most used anti-cancer drugs worldwide. Due to its insolubility in water, the clinically available liquid formulation of PTX contains Cremophor EL that is responsible for severe hypersensitivity. Albumin-based nanoparticles have emerged as a promising carrier for anti-cancer drugs because albumin nanoparticles have high capacity to not only load lipophilic drugs without solubilizer but also accumulate in tumor by both passive and active mechanisms. In this study, we attempted to prepare solvent-free formulation of PTX-loaded bovine serum albumin (BSA) nanoparticles with high stability, and the in vitro stability in serum were comparatively assessed between our PTX-loaded BSA nanoparticles and clinically used nanoparticulate albumin-bound PTX (Abraxane®). PTX-loaded BSA nanoparticles were prepared by intermolecular disulfide crosslinking. When BSA molecules were used without denaturation by guanidinium, the obtained BSA nanoparticles showed broad size distribution. On the other hand, the nanoparticles composed of denatured BSA by guanidinium had a uniform size around 100 nm. The PTX encapsulation efficiency of BSA nanoparticles were approximately 30-40 %. In addition, in vitro gel filtration analysis and dialysis study demonstrated that PTX-loaded BSA nanoparticles had higher colloidal stability and sustained PTX release property than Abraxane® in serum. These results suggest that BSA nanoparticles is a promising drug carrier for improving therapeutic efficacy of PTX and reducing its adverse effects.

Preparation and anti-tumor activity of paclitaxel silk protein nanoparticles encapsulated by biofilm

In order to overcome the poor bioavailability of paclitaxel (PTX), in this study, self-assembled paclitaxel silk fibronectin nanoparticles (PTX-SF-NPs) were encapsulated with outer membrane vesicles of Escherichia coli (E. coil), and biofilm-encapsulated paclitaxel silk fibronectin nanoparticles (OMV-PTX-SF-NPs) were prepared by high-pressure co-extrusion, the size and zeta potential of the OMV-PTX-SF-NPs were measured. The antitumor effects of OMV-PTX-SF-NPs were evaluated by cellular and pharmacodynamic assays, and pharmacokinetic experiments were performed. The results showed that hydrophobic forces and hydrogen bonding played a major role in the interaction between paclitaxel and filipin proteins, and the size of OMV-PTX-SF-NPs was 199.8 ± 2.8 nm, zeta potential was -17.8 ± 1.3 mv. The cellular and in vivo pharmacokinetic assays demonstrated that the OMV-PTX-SF-NPs possessed a promising antitumor effect. Pharmacokinetic experiments showed that the AUC0-∞ of OMV-PTX-SF-NPs was 5.314 ± 0.77, which was much larger than that of free PTX, which was 0.744 ± 0.14. Overall, we have successfully constructed a stable oral formulation of paclitaxel with a sustained-release effect, which is able to effectively increase the bioavailability of paclitaxel, improve the antitumor activity, and reduce the adverse effects.

Synergism and attenuation of triptolide through prodrug engineering combined with liposomal scaffold strategy to enhance inhibition in pancreatic cancer

The prognosis of pancreatic cancer (PCa) is extremely poor because of its resistance to conventional therapies. Many previous studies have demonstrated that triptolide (TPL) has a potent tumoricidal activity on PCa. However, the clinical application of TPL in tumor therapy has been greatly limited by its poor aqueous solubility, short half-time, high toxicity and inefficient delivery. Here, through the engineering of prodrug technology combined with the nanodrug-delivery system (NDDS) strategy, we modified the main active site of TPL C14-OH by esterification reaction to obtain a highly lipophilic prodrug, and then encapsulated the drug in a phospholipid bilayer in liposomal vehicles through the thin-film hydration method for efficient delivery. A delivery system based on TPL lignocerate liposomes (TPL-LA-lip) for drug loading for targeted therapy against PCa was established. Our results showed that TPL-LA demonstrates exceptional compatibility with the phospholipid layer of liposomes, thereby enhancing drug retention in liposomal vehicle and improving tumor targeting and cellular uptake. Moreover, The system of TPL-LA-lip exhibited a sustained drug release profile in vitro, and intravenous administration significantly impedes tumor progression while reducing the toxicity of TPL in the PCa mouse model. These results demonstrated that the prodrug-loaded liposomes could significantly reduce the toxicity of TPL and enhance the biosafety. Overall, this prodrug approach is a simple and effective method to transform the highly toxic TPL into a safe and efficacious nanomedicine with excellent in vivo tolerability for PCa treatment.

(Nano)platforms in breast cancer therapy: Drug/gene delivery, advanced nanocarriers and immunotherapy

Breast cancer is the most malignant tumor in women, and there is no absolute cure for it. Although treatment modalities including surgery, chemotherapy, and radiotherapy are utilized for breast cancer, it is still a life-threatening disease for humans. Nanomedicine has provided a new opportunity in breast cancer treatment, which is the focus of the current study. The nanocarriers deliver chemotherapeutic agents and natural products, both of which increase cytotoxicity against breast tumor cells and prevent the development of drug resistance. The efficacy of gene therapy is boosted by nanoparticles and the delivery of CRISPR/Cas9, Noncoding RNAs, and RNAi, promoting their potential for gene expression regulation. The drug and gene codelivery by nanoparticles can exert a synergistic impact on breast tumors and enhance cellular uptake via endocytosis. Nanostructures are able to induce photothermal and photodynamic therapy for breast tumor ablation via cell death induction. The nanoparticles can provide tumor microenvironment remodeling and repolarization of macrophages for antitumor immunity. The stimuli-responsive nanocarriers, including pH-, redox-, and light-sensitive, can mediate targeted suppression of breast tumors. Besides, nanoparticles can provide a diagnosis of breast cancer and detect biomarkers. Various kinds of nanoparticles have been employed for breast cancer therapy, including carbon-, lipid-, polymeric- and metal-based nanostructures, which are different in terms of biocompatibility and delivery efficiency.

Evaluation of cell membrane-derived nanoparticles as therapeutic carriers for pancreatic ductal adenocarcinoma using an in vitro tumour stroma model

Here, we fabricated nanoparticles made solely from the membrane of cells found in the pancreatic tumour's microenvironment (TME), like the human MiaPaCa-2 cells and M2-polarized macrophages. The cell membrane-derived nanoparticles (CMNPs) deriving from the MiaPaCa-2 cells (MPC2-CMNPs) were loaded with the chemotherapeutic drug paclitaxel (PTX), and the CMNPs deriving from M2-polarized macrophages (M2-CMNPs) were loaded with the colony-stimulating factor 1 receptor inhibitor, pexidartinib (PXDB). The CMNPs' thorough morphological and physicochemical characterisation was followed by an in-depth study of their targeting ability and the endocytosis pathway involved during their internalisation. An in vitro model of the desmoplastic stroma comprising cancer-associated fibroblast-mimicking cells and M2-polarized macrophages was also developed. The model was characterised by collagen and α-smooth muscle actin (α-SMA) expression (overexpressed in desmoplasia) and was used to assess the CMNPs' ability to cross the stroma and target the tumour cells. Moreover, we assessed the effect of PXDB-loaded M2-CMNPs on the expression of M1 (CD80/CD86) and M2 (CD206/CD209) polarisation markers on activated macrophages. Finally, we evaluated the PTX and PXDB-loaded CMNPs' effect on the viability of all the used TME cell lines alone or in combination. Overall, this pilot study showed the potential of the CMNPs to cross an in vitro stroma model and act synergistically to treat PDAC.

Human Serum Albumin Based Nanodrug Delivery Systems: Recent Advances and Future Perspective

With the success of several clinical trials of products based on human serum albumin (HSA) and the rapid development of nanotechnology, HSA-based nanodrug delivery systems (HBNDSs) have received extensive attention in the field of nanomedicine. However, there is still a lack of comprehensive reviews exploring the broader scope of HBNDSs in biomedical applications beyond cancer therapy. To address this gap, this review takes a systematic approach. Firstly, it focuses on the crystal structure and the potential binding sites of HSA. Additionally, it provides a comprehensive summary of recent progresses in the field of HBNDSs for various biomedical applications over the past five years, categorized according to the type of therapeutic drugs loaded onto HSA. These categories include small-molecule drugs, inorganic materials and bioactive ingredients. Finally, the review summarizes the characteristics and current application status of HBNDSs in drug delivery, and also discusses the challenges that need to be addressed for the clinical transformation of HSA formulations and offers future perspectives in this field.

An oncolytic adenovirus coding for a variant interleukin 2 cytokine improves response to chemotherapy through enhancement of effector lymphocyte cytotoxicity, fibroblast compartment modulation and mitotic slippage

Pancreatic ductal adenocarcinoma (PDAC) is a highly treatment-resistant cancer. Currently, the only curative treatment for PDAC is surgery, but most patients are diagnosed with metastatic disease and thus outside the scope of surgery. The majority of metastatic patients receive chemotherapy, but responses are limited. New therapeutics are thus urgently needed for PDAC. One major limitation in treating PDAC has been the highly immunosuppressive tumor microenvironment (TME) which inhibits anti-cancer immune responses. We have constructed an oncolytic adenovirus coding for a variant the interleukin 2 molecule, Ad5/3-E2F-d24-vIL2 (also known as TILT-452, and "vIL-2 virus"), with preferential binding to IL-2 receptors on the surface of effector lymphocytes over T regulatory cells (T regs). In the present study this virus was evaluated in combination with nab-paclitaxel and gemcitabine chemotherapy in Panc02 mouse model. Ad5/3-E2F-d24-vIL2 showed marked PDAC cell killing in vitro, alongside induction of mitotic slippage and immunogenic cell death in PDAC cell lines, when combined with chemotherapy. Increased survival was seen in vivo with 80% of animals surviving long term, when compared to chemotherapy alone. Moreover, combination therapy mediated enhanced tumor growth control, without observable toxicities in internal organs or external features. Survival and tumor control benefits were associated with activation of tumor infiltrating immune cells, downregulation of inhibitory signals, change in fibroblast populations in the tumors and changes in intratumoral cytokines, with increased chemokine amounts (CCL2, CCL3, CCL4) and anti-tumor cytokines (IFN-γ and TNFα). Furthermore, vIL-2 virus in combination with chemotherapy efficiently induced tumor protection upon rechallenge, that was extended to a previously non-encountered cancer cell line. In conclusion, Ad5/3-E2F-d24-vIL2 is a promising immunotherapy candidate when combined with nab-paclitaxel and gemcitabine.

The application of nanomedicine in clinical settings

As nanotechnology develops in the fields of mechanical engineering, electrical engineering, information and communication, and medical care, it has shown great promises. In recent years, medical nanorobots have made significant progress in terms of the selection of materials, fabrication methods, driving force sources, and clinical applications, such as nanomedicine. It involves bypassing biological tissues and delivering drugs directly to lesions and target cells using nanorobots, thus increasing concentration. It has also proved useful for monitoring disease progression, complementary diagnosis, and minimally invasive surgery. Also, we examine the development of nanomedicine and its applications in medicine, focusing on the use of nanomedicine in the treatment of various major diseases, including how they are generalized and how they are modified. The purpose of this review is to provide a summary and discussion of current research for the future development in nanomedicine.

PLGA nanoparticles loaded with curcumin produced luminescence for cell bioimaging

To revise the emission of curcumin (Cur) from "off" to "on", poly (D, L-lactide-co-glycolide) acid (PLGA) nanoparticles loaded with Cur were embedded in a polyvinyl alcohol (PVA) emulsifier (named Cur@PLGA-NPs). First, the emission intensities of different nanoformulations, including liposomes, bovine serum albumin (BSA) nanoparticles, and PLGA nanoparticles, were examined to discover the most effective carriers for Cur luminescence. As a result, Cur@PLGA-NPs exhibited the highest fluorescence intensity due to aggregation-induced emission (AIE), with quantum yields of 23.78% in aqueous solution and 21.52% in the solid state. According to X-ray diffraction (XRD) data, Cur@PLGA-NPs existed in the amorphous state, with a size of 217.2 ± 5.2 nm, an encapsulation efficiency (EE) of 69.98%, and a drug loading efficiency (LE) of 1.37%. The intramolecular interactions, which included hydrophobic interactions, electrostatic interactions, π-π interactions and solvatochromic effects, stabilized the chromophore cluster of Cur@PLGA-NPs in terms of nanoparticle formulation. Compared with free Cur, Cur@PLGA-NPs sensitized CT26 cells more efficiently with an IC₅₀ value of 16.9 μmol/L and an apoptotic rate of 17.20% at 10 μmol/L Cur. Because of the robust fluorescence emission based on AIE, Cur@PLGA-NPs were utilized as a nano-AIE probe for cell bioimaging, and many red fluorescent signals were observed in CT26 cells after treatment. These results suggest that Cur@PLGA-NPs provide a novel amorphous AIE formulation with imaging and bioactive capabilities.

Paclitaxel and docetaxel resistance in prostate cancer: Molecular mechanisms and possible therapeutic strategies

Prostate cancer is among most malignant tumors around the world and this urological tumor can be developed as result of genomic mutations and their accumulation during progression towards advanced stage. Due to lack of specific symptoms in early stages of prostate cancer, most cancer patients are diagnosed in advanced stages that tumor cells display low response to chemotherapy. Furthermore, genomic mutations in prostate cancer enhance the aggressiveness of tumor cells. Docetaxel and paclitaxel are suggested as well-known compounds for chemotherapy of prostate tumor and they possess a similar function in cancer therapy that is based on inhibiting depolymerization of microtubules, impairing balance of microtubules and subsequent delay in cell cycle progression. The aim of current review is to highlight mechanisms of paclitaxel and docetaxel resistance in prostate cancer. When oncogenic factors such as CD133 display upregulation and PTEN as tumor-suppressor shows decrease in expression, malignancy of prostate tumor cells enhances and they can induce drug resistance. Furthermore, phytochemicals as anti-tumor compounds have been utilized in suppressing chemoresistance in prostate cancer. Naringenin and lovastatin are among the anti-tumor compounds that have been used for impairing progression of prostate tumor and enhancing drug sensitivity. Moreover, nanostructures such as polymeric micelles and nanobubbles have been utilized in delivery of anti-tumor compounds and decreasing risk of chemoresistance development. These subjects are highlighted in current review to provide new insight for reversing drug resistance in prostate cancer.

Nanoparticles loaded with pharmacologically active plant-derived natural products: Biomedical applications and toxicity

Pharmacologically active natural products have played a significant role in the history of drug development. They have acted as sources of therapeutic drugs for various diseases such as cancer and infectious diseases. However, most natural products suffer from poor water solubility and low bioavailability, limiting their clinical applications. The rapid development of nanotechnology has opened up new directions for applying natural products and numerous studies have explored the biomedical applications of nanomaterials loaded with natural products. This review covers the recent research on applying plant-derived natural products (PDNPs) nanomaterials, including nanomedicines loaded with flavonoids, non-flavonoid polyphenols, alkaloids, and quinones, especially their use in treating various diseases. Furthermore, some drugs derived from natural products can be toxic to the body, so the toxicity of them is discussed. This comprehensive review includes fundamental discoveries and exploratory advances in natural product-loaded nanomaterials that may be helpful for future clinical development.

Natural Taxanes: From Plant Composition to Human Pharmacology and Toxicity

Biologically active taxanes, present in small- to medium-sized evergreen conifers of various Taxus species, are widely used for their antioxidant, antimicrobial and anti-inflammatory effects, but mostly for their antitumour effects used in the treatment of solid tumours of the breast, ovary, lung, bladder, prostate, oesophagus and melanoma. More of the substances found in Taxus plant extracts have medical potential. Therefore, at the beginning of this review, we describe the methods of isolation, identification and determination of taxanes in different plant parts. One of the most important taxanes is paclitaxel, for which we summarize the pharmacokinetic parameters of its different formulations. We also describe toxicological risks during clinical therapy such as hypersensitivity, neurotoxicity, gastrointestinal, cardiovascular, haematological, skin and renal toxicity and toxicity to the respiratory system. Since the effect of the drug-form PTX is enhanced by various Taxus spp. extracts, we summarize published clinical intoxications and all fatal poisonings for the Taxus baccata plant. This showed that, despite their significant use in anticancer treatment, attention should also be focused on the risk of fatal intoxication due to ingestion of extracts from these plants, which are commonly found in our surroundings.

Anti-lung cancer effect of paclitaxel solid lipid nanoparticles delivery system with curcumin as co-loading partner in vitro and in vivo

The main aim of this study was to improve the therapeutic potential of a paclitaxel (PTX) and curcumin (CU) combination regimen using solid lipid nanoparticles (SLNs). PTX and CU were successfully co-encapsulated at a predetermined ratio in SLNs (PC-SLNs) with high encapsulation efficiency (CU: 97.6%, PTX: 95.8%), appropriate particle size (121.8 ± 1.69 nm), small PDI (0.267 ± 0.023), and negative zeta potential (–30.4 ± 1.25 mV). Compared with PTX or the combination of CU and PTX (CU + PTX), PC-SLNs can greatly reduce the dose of PTX while still achieving the same therapeutic effect on four cancer cell lines, among which the inhibitory effect on A549 lung cancer cells was the strongest. PC-SLNs improved the area under the curve (CU: 1.40-fold; PTX: 2.88-fold), prolonged the residence time (CU: 6.94-fold; PTX: 2.51-fold), and increased the half-life (CU: 5.62-fold; PTX: 6.46-fold), achieving long circulation. PC-SLNs were used to treat lung cancer in a nude mouse xenograft tumor model and the tumor suppression rate reached 78.42%, while those of PTX and (CU + PTX) were 40.53% and 51.56%, respectively. As PC-SLNs can prevent P-glycoprotein efflux, reverse MDR and downregulate the NF-κB pathway. PC-SLNs are a potential antineoplastic agent that is more effective and less toxic in treating lung cancer.

Taxanes prodrug-based nanomedicines for cancer therapy

Malignant tumor remains a huge threat to human health and chemotherapy still occupies an important place in clinical tumor treatment. As a kind of potent antimitotic agent, taxanes act as the first-line broad-spectrum cancer drug in clinical use. However, disadvantages such as prominent hydrophobicity, severe off-target toxicity or multidrug resistance lead to unsatisfactory therapeutic effects, which restricts its wider usage. The efficient delivery of taxanes is still quite a challenge despite the rapid developments in biomaterials and nanotechnology. Great progress has been made in prodrug-based nanomedicines (PNS) for cancer therapy due to their outstanding advantages such as high drug loading efficiency, low carrier induced immunogenicity, tumor stimuli-responsive drug release, combinational therapy and so on. Based on the numerous developments in this filed, this review summarized latest updates of taxanes prodrugs-based nanomedicines (TPNS), focusing on polymer-drug conjugate-based nanoformulations, small molecular prodrug-based self-assembled nanoparticles and prodrug-encapsulated nanosystems. In addition, the new trends of tumor stimuli-responsive TPNS were also discussed. Moreover, the future challenges of TPNS for clinical translation were highlighted. We here expect this review will inspire researchers to explore more practical taxanes prodrug-based nano-delivery systems for clinical use.

Targeted delivery of albumin nanoparticles for breast cancer: A review

Breast cancer has been identified as one of the most common cancers diagnosed in women. Various nanotechnology platforms offering unique features are considered in breast cancer treatment. Albumin is a versatile biodegradable, biocompatible, non-toxic and non-immunogenic protein nanocarrier. These characteristics attracted strong attention to fabricate albumin nanoparticles to deliver chemotherapeutic agents without major adverse effects. Albumin nanoparticles can undergo surface modifications using different ligands promoting tumor-targeted drug delivery. Moreover, multifunctional albumin nanoparticle is an upcoming strategy to attain efficient cancer therapy. This review gives an account of the potential albumin nanoparticles developed for chemotherapeutic drug delivery and its targeted approach for breast cancer. It also covers different multifunctional therapies available using albumin nanoparticles as breast cancer theranostics.