Facile one-pot formulation of TRAIL-embedded paclitaxel-bound albumin nanoparticles for the treatment of pancreatic cancer

Human Serum Albumin Nanoparticles as a Carrier of 20(S)-Protopanaxadiol via Intramuscular Injection to Alleviate Cyclophosphamide-Induced Myelosuppression

Myelosuppression is a prevalent and potentially life-threatening side effect during chemotherapy. As the main active component of ginseng, 20(S)-protopanaxadiol (PPD) is capable of relieving myelosuppression by restoring hematopoiesis and immunity. In this study, PPD was encapsulated in human albumin nanoparticles (PPD-HSA NPs) by nanoparticle albumin-bound (Nab) technology for intramuscular injection to optimize its pharmacokinetic properties and promote recovery of myelosuppression. The prepared PPD-HSA NPs had a particle size of about 280 nm with a narrow size distribution. PPD dispersed as an amorphous state within the PPD-HSA NPs, and the NPs exhibited in vitro sustained release behavior. PPD-HSA NPs showed a favorable pharmacokinetic profile with high absolute bioavailability, probably due to the fact that NPs entered into the blood circulation via lymphatic circulation and were eliminated slowly. In vivo distribution experiments demonstrated that PPD-HSA NPs were mainly distributed in the liver and spleen, but a strong fluorescence signal was also found in the inguinal lymph node, indicating drug absorption via a lymph route. The myelosuppressive model was established using cyclophosphamide as the inducer. Pharmacodynamic studies confirmed that PPD-HSA NPs were effective in promoting the level of white blood cells. Moreover, the neutrophil and lymphocyte counts were significantly higher in the PPD-HSA NPs group compared with the control group. This preliminary investigation revealed that PPD-HSA NPs via intramuscular administration may be an effective intervention strategy to alleviate myelosuppression.

Target-Specific Nanoparticle Polyplex Down-Regulates Mutant Kras to Prevent Pancreatic Carcinogenesis and Halt Tumor Progression

Survival from pancreatic cancer is poor because most cancers are diagnosed in the late stages and there are no therapies to prevent the progression of precancerous pancreatic intraepithelial neoplasms (PanINs). Inhibiting mutant KRAS^G12D, the primary driver mutation in most human pancreatic cancers, has been challenging. The cholecystokinin-B receptor (CCK-BR) is absent in the normal pancreas but becomes expressed in high grade PanIN lesions and is over-expressed in pancreatic cancer making it a prime target for therapy. We developed a biodegradable nanoparticle polyplex (NP) that binds selectively to the CCK-BR on PanINs and pancreatic cancer to deliver gene therapy. PanIN progression was halted and the pancreas extracellular matrix rendered less carcinogenic in P48-Cre/LSL-Kras^G12D/+ mice treated with the CCK-BR targeted NP loaded with siRNA to mutant Kras. The targeted NP also slowed proliferation, decreased metastases and improved survival in mice bearing large orthotopic pancreatic tumors. Safety and toxicity studies were performed in immune competent mice after short or long-term exposure and showed no off-target toxicity by histological or biochemical evaluation. Precision therapy with target-specific NPs provides a novel approach to slow progression of advanced pancreatic cancer and also prevents the development of pancreatic cancer in high-risk subjects without toxicity to other tissues.

Targeting TRAIL Death Receptors in Triple-Negative Breast Cancers: Challenges and Strategies for Cancer Therapy

The tumor necrosis factor (TNF) superfamily member TNF-related apoptosis-inducing ligand (TRAIL) induces apoptosis in cancer cells via death receptor (DR) activation with little toxicity to normal cells or tissues. The selectivity for activating apoptosis in cancer cells confers an ideal therapeutic characteristic to TRAIL, which has led to the development and clinical testing of many DR agonists. However, TRAIL/DR targeting therapies have been widely ineffective in clinical trials of various malignancies for reasons that remain poorly understood. Triple negative breast cancer (TNBC) has the worst prognosis among breast cancers. Targeting the TRAIL DR pathway has shown notable efficacy in a subset of TNBC in preclinical models but again has not shown appreciable activity in clinical trials. In this review, we will discuss the signaling components and mechanisms governing TRAIL pathway activation and clinical trial findings discussed with a focus on TNBC. Challenges and potential solutions for using DR agonists in the clinic are also discussed, including consideration of the pharmacokinetic and pharmacodynamic properties of DR agonists, patient selection by predictive biomarkers, and potential combination therapies. Moreover, recent findings on the impact of TRAIL treatment on the immune response, as well as novel strategies to address those challenges, are discussed.

Tissue-reactive drugs enable materials-free local depots

Local, sustained drug delivery of potent therapeutics holds promise for the treatment of a myriad of localized diseases while eliminating systemic side effects. However, introduction of drug delivery depots such as viscous hydrogels or polymer-based implants is highly limited in stiff tissues such as desmoplastic tumors. Here, we present a method to create materials-free intratumoral drug depots through Tissue-Reactive Anchoring Pharmaceuticals (TRAPs). TRAPs diffuse into tissue and attach locally for sustained drug release. In TRAPs, potent drugs are modified with ECM-reactive groups and then locally injected to quickly react with accessible amines within the ECM, creating local drug depots. We demonstrate that locally injected TRAPs create dispersed, stable intratumoral depots deep within mouse and human pancreatic tumor tissues. TRAPs depots based on ECM-reactive paclitaxel (TRAP paclitaxel) had better solubility than free paclitaxel and enabled sustained in vitro and in vivo drug release. TRAP paclitaxel induced higher tumoral apoptosis and sustained better antitumor efficacy than the free drug. By providing continuous drug access to tumor cells, this material-free approach to sustained drug delivery of potent therapeutics has the potential in a wide variety of diseases where current injectable depots fall short.

Combined Antitumor Therapy Using In Situ Injectable Hydrogels Formulated with Albumin Nanoparticles Containing Indocyanine Green, Chlorin e6, and Perfluorocarbon in Hypoxic Tumors

Combined therapy using photothermal and photodynamic treatments together with chemotherapeutic agents is considered one of the most synergistic treatment protocols to ablate hypoxic tumors. Herein, we sought to fabricate an in situ-injectable PEG hydrogel system having such multifunctional effects. This PEG hydrogel was prepared with (i) nab^TM-technique-based paclitaxel (PTX)-bound albumin nanoparticles with chlorin-e6 (Ce6)-conjugated bovine serum albumin (BSA-Ce6) and indocyanine green (ICG), named ICG/PTX/BSA-Ce6-NPs (~175 nm), and (ii) an albumin-stabilized perfluorocarbon (PFC) nano-emulsion (BSA-PFC-NEs; ~320 nm). This multifunctional PEG hydrogel induced moderate and severe hyperthermia (41−42 °C and >48 °C, respectively) at the target site under two different 808 nm laser irradiation protocols, and also induced efficient singlet oxygen (¹O₂) generation under 660 nm laser irradiation supplemented by oxygen produced by ultrasound-triggered PFC. Due to such multifunctionality, our PEG hydrogel formula displayed significantly enhanced killing of three-dimensional 4T1 cell spheroids and also suppressed the growth of xenografted 4T1 cell tumors in mice (tumor volume: 47.7 ± 11.6 and 63.4 ± 13.0 mm³ for photothermal and photodynamic treatment, respectively, vs. PBS group (805.9 ± 138.5 mm³), presumably based on sufficient generation of moderate heat as well as ¹O₂/O₂ even under hypoxic conditions. Our PEG hydrogel formula also showed excellent hyperthermal efficacy (>50 °C), ablating the 4T1 tumors when the irradiation duration was extended and output intensity was increased. We expect that our multifunctional PEG hydrogel formula will become a prototype for ablation of otherwise poorly responsive hypoxic tumors.

Photoreactive-proton-generating hyaluronidase/albumin nanoparticles-loaded PEG-hydrogel enhances antitumor efficacy and disruption of the hyaluronic acid extracellular matrix in AsPC-1 tumors

Depletion of tumor extracellular matrix (ECM) is viewed as a promising approach to enhance the antitumor efficacy of chemotherapeutic-loaded nanoparticles. Hyaluronidase (HAase) destroys hyaluronic acid-based tumor ECM, but it is active solely at acidic pHs of around 5.0 and is much less active at physiological pH. Herein, we report the development of our novel UV-light-reactive proton-generating and hyaluronidase-loaded albumin nanoparticles (o-NBA/HAase-HSA-NPs). The method to prepare the nanoparticles was based on pH-jump chemistry using o-nitrobenzaldehyde (o-NBA) in an attempt to address the clinical limitation of HAase. When in suspension/PEG-hydrogel and irradiated with UV light, the prepared o-NBA/HAase-HSA-NPs clearly reduced the pH of the surrounding medium to as low as 5.0 by producing protons and were better able to break down HA-based tumor cell spheroids (AsPC-1) and HA-hydrogel/microgels, presumably due to the enhanced HA activity at a more optimal pH. Moreover, when formulated as an intratumor-injectable PEG hydrogel, the o-NBA/HAase-HSA-NPs displayed significantly enhanced tumor suppression when combined with intravenous paclitaxel-loaded HSA-NPs (PTX-HSA-NPs) in AsPC-1 tumor-bearing mice: The tumor volume in mice administered UV-activated o-NBA/HAase-HSA-NPs and PTX-HSA-NPs was 198.2 ​± ​30.0 ​mm³, whereas those administered PBS or non-UV-activated o-NBA/HAase-HSA-NPs and PTX-HSA-NPs had tumor volumes of 1230.2 ​± ​256.2 and 295.4 ​± ​17.1 ​mm³, respectively. These results clearly demonstrated that when administered with paclitaxel NPs, our photoreactive o-NBA/HAase-HSA-NPs were able to reduce pH and degrade HA-based ECM, and thereby significantly suppress tumor growth. Consequently, we propose our o-NBA/HAase-HSA-NPs may be a prototype for development of future nanoparticle-based HA-ECM-depleting tumor-ablating agents.

Harnessing TRAIL-Induced Apoptosis Pathway for Cancer Immunotherapy and Associated Challenges

The immune cytokine tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has attracted rapidly evolving attention as a cancer treatment modality because of its competence to selectively eliminate tumor cells without instigating toxicity in vivo. TRAIL has revealed encouraging promise in preclinical reports in animal models as a cancer treatment option; however, the foremost constraint of the TRAIL therapy is the advancement of TRAIL resistance through a myriad of mechanisms in tumor cells. Investigations have documented that improvement of the expression of anti-apoptotic proteins and survival or proliferation involved signaling pathways concurrently suppressing the expression of pro-apoptotic proteins along with down-regulation of expression of TRAILR1 and TRAILR2, also known as death receptor 4 and 5 (DR4/5) are reliable for tumor cells resistance to TRAIL. Therefore, it seems that the development of a therapeutic approach for overcoming TRAIL resistance is of paramount importance. Studies currently have shown that combined treatment with anti-tumor agents, ranging from synthetic agents to natural products, and TRAIL could result in induction of apoptosis in TRAIL-resistant cells. Also, human mesenchymal stem/stromal cells (MSCs) engineered to generate and deliver TRAIL can provide both targeted and continued delivery of this apoptosis-inducing cytokine. Similarly, nanoparticle (NPs)-based TRAIL delivery offers novel platforms to defeat barricades to TRAIL therapeutic delivery. In the current review, we will focus on underlying mechanisms contributed to inducing resistance to TRAIL in tumor cells, and also discuss recent findings concerning the therapeutic efficacy of combined treatment of TRAIL with other antitumor compounds, and also TRAIL-delivery using human MSCs and NPs to overcome tumor cells resistance to TRAIL.

TPGS and chondroitin sulfate dual-modified lipid-albumin nanosystem for targeted delivery of chemotherapeutic agent against multidrug-resistant cancer

Multidrug resistance (MDR) remains the primary issue leading to the failure of chemotherapy. In this study, a d-α-tocopherol polyethylene 1000 glycol succinate (TPGS) and chondroitin sulfate (CS) dual-modified lipid-albumin nanosystem was constructed for targeted delivery of paclitaxel (PTX) in treating MDR cancer. The obtained nanosystem (TLA/PTX@CS) had an average size of around 176 nm and a negative zeta potential of around -18 mV. TPGS was confirmed to improve the intracellular accumulation of PTX and facilitate the mitochondrial-targeting of lipid-albumin nanosystem. Functionalized with the outer CS shell, TLA/PTX@CS entered MDR breast cancer (MCF-7/MDR) cells via CD44 receptor-mediated endocytosis. CS shell was degraded by concentrated hyaluronidase in the lysosomes, thereby releasing PTX into cytoplasm and inhibiting cell proliferation. In vivo studies revealed that TLA/PTX@CS possessed prolonged blood circulation, resulting in elevated tumor accumulation, excellent antitumor efficacy with a tumor inhibition ratio of 75.3%, and significant survival benefit in MCF-7/MDR tumor-bearing mice. Hence, this TPGS and CS dual-modified lipid-albumin nanosystem provides a promising strategy for targeted delivery of chemotherapeutic drug and reversal of MDR in cancer treatment.

Tailor-Made Nanomaterials for Diagnosis and Therapy of Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers worldwide due to its aggressiveness and the challenge to early diagnosis and treatment. In recent decades, nanomaterials have received increasing attention for diagnosis and therapy of PDAC. However, these designs are mainly focused on the macroscopic tumor therapeutic effect, while the crucial nano-bio interactions in the heterogeneous microenvironment of PDAC remain poorly understood. As a result, the majority of potent nanomedicines show limited performance in ameliorating PDAC in clinical translation. Therefore, exploiting the unique nature of the PDAC by detecting potential biomarkers together with a deep understanding of nano-bio interactions that occur in the tumor microenvironment is pivotal to the design of PDAC-tailored effective nanomedicine. This review will introduce tailor-made nanomaterials-enabled laboratory tests and advanced noninvasive imaging technologies for early and accurate diagnosis of PDAC. Moreover, the fabrication of a myriad of tailor-made nanomaterials for various PDAC therapeutic modalities will be reviewed. Furthermore, much preferred theranostic multifunctional nanomaterials for imaging-guided therapies of PDAC will be elaborated. Lastly, the prospects of these nanomaterials in terms of clinical translation and potential breakthroughs will be briefly discussed.

Hyperthermal paclitaxel-bound albumin nanoparticles co-loaded with indocyanine green and hyaluronidase for treating pancreatic cancers

Albumin nanoparticles have become an attractive cancer nanomedicine platform due to their pharmaceutical advantages. Recently, photothermal therapy has been extensively applied to cancer treatment due to heat-induced tumor ablation. Herein, we fabricated albumin nanoparticles (HSA-NPs) loaded with paclitaxel (PTX), indocyanine green (ICG; a hyperthermal agent) and hyaluronidase (HAase) that breaks down hyaluronan, a major component of the extracellular matrix (ECM) in tumors. Synthesis was based on a slightly modified nanoparticle albumin-bound (Nab™) technique. The prepared nanoparticles (PTX/ICG/HAase-HSA-NPs) had a spherical shape with an average size of ~ 110 nm and a zeta potential of ~ -30.4 mV. They displayed good colloidal stability and typical patterns of ICG, HSA and HAase in UV-VIS-NIR and circular dichroism spectroscopic analysis. PTX/ICG/HAase-HSA-NPs were found to have excellent hyperthermal effects in response to near-infrared laser irradiation (808 nm) (up to > 50 °C over 4 min). The hyperthermia conducted by PTX/ICG/HAase-HSA-NPs resulted in significant cytotoxicity to pancreatic AsPC-1 cells at both severe (> 50 °C) and mild (41-42 °C) hyperthermal states in conjunction with the inherent cytotoxic activity of paclitaxel. Furthermore, the confocal images of AsPC-1 cell spheroids proved PTX/ICG/HAase-HSA-NPs were able to permeate deeply into the three-dimensional tumor tissue mimicry structure. Most of all, PTX/ICG/HAase-HSA-NPs maintained all these physicochemical and anti-cancer properties irrespective of the amount of embedded HAase (1-5 mg). Our results demonstrated that PTX/ICG/HAase-HSA-NPs are a promising hyperthermal/chemotherapeutic anticancer agent.

Quality by design (QbD) approach in processing polymeric nanoparticles loading anticancer drugs by high pressure homogenizer

Polymeric nanoparticles prepared using high pressure homogenizer (HPH) present some unique challenges during manufacturing which can be better understood by application of quality by design (QbD) approaches. The present review highlights the ways to identify the critical material attributes which includes the anticancer drugs, polymers, surfactants, solvent system and dispersion system. A comprehensive understanding of the critical processing parameters like pressure and number of cycles during the working of HPH used in putting forward the critical quality attributes such as size, shape, surface charge or droplet stabilization. Such QbD approach will involve development of an effective control strategy for would ensure safe encapsulation of anticancer drugs for successful product development. Proper addressing of the issues related to scaling-up would lead to successful commercialization of the nano-sized formulations loaded with anticancer drugs.

Development and validation of a thermal desorber gas chromatography method for determination of residual solvents in drug loaded albumin

The conventional approach for residual solvent (RS) analysis is headspace-gas chromatography (HS-GC). This starts from a homogenous sample solution and is based on the equilibrium of the analyte between the sample and the gas phase. Unfortunately, aqueous solutions of albumin form irreversible hydrophobic aggregates when heated above 50 °C. Consequently, the use of HS-GC for RS analysis in albumin becomes problematic due to the presence of an additional solid phase in the HS vial. In this work, a method using a thermal desorber (TD) combined with GC was developed for the determination of RS in drug loaded albumin. Samples were immobilized between two double layers of quartz filter (QF) in a polytetrafluoroethylene (PTFE) insert which was placed in an empty desorption tube prior to TD-GC analysis. The liquid standard mix consisted of ethanol (EtOH), acetone (Ace), dichloromethane (DCM) and chloroform (Chl) dissolved in toluene. Offline liquid calibration (OLC) was applied by introducing 2 μL of the standard mix under counter flow of an inert gas into the TD tube containing a mixed bed of mesoporous silica (MPSi) immobilized between two double layers of QF. The OLC results were verified using the inline liquid calibration (ILC) approach based on a heated GC injector installed on the TD. The validation results revealed that the proposed method has good recovery (> 98 %). R²-values (> 0.998) indicated good linearity over a wide range. The limit of detection (LOD) and limit of quantification (LOQ) were found to be 0.01 and 0.04 μg on tube, respectively. Repeatability of the method was reported as RSD-values and they were lower than 3 %. A method based on the complete enzymatic digestion of albumin combined with conventional HS-GC was developed to verify the completeness of release of the RS from the albumin. Both the TD-GC and HS-GC methods were applied for the determination of EtOH and DCM in two different albumin samples loaded with experimental drugs. Statistical comparison indicated that there was no significant difference (p > 0.05) between the two methods. However, the HS-GC method following enzymatic degradation is much more expensive and time consuming.

Liver Targeting Albumin-Coated Silybin-Phospholipid Particles Prepared by Nab™ Technology for Improving Treatment Effect of Acute Liver Damage in Intravenous Administration

In this study, a novel human serum albumin nanoparticle loading silybin-phospholipid complex (SLNPs) was developed for liver targeting after intravenous administration. The preparation of the drug delivery system consisted of two steps; initially, a silybin-phospholipid complex (SLC) was produced to improve the lipophilicity of SLB to then achieve enhanced encapsulation of SLB in albumin nanoparticles. FT-IR and XRD analysis confirmed the successful formation of SLC. The complex ratio of SLC in the first step was 99.6%. The encapsulation efficiency and drug loading of SLNPs in the second step were 96.2% and 5.6%, respectively. SLNPs were spherical and well-dispersed, with a zeta potential of approximately - 10 mV, and a mean particle size around 200 nm. An in vivo tissue distribution experiment and a pharmacodynamic experiment showed that, compared with SLB solution, SLNPs had an improved SLB accumulation in the liver. The hepatoprotective effect of SLNPs on CCl₄-induced acute liver damage was evaluated. CCl₄-damaged mice showed an increased enzymatic activity of ALT and AST; however, enzyme levels returned to near-normal levels in high-dose SLNP-treated mice. As SLNPs combine the enhanced oil solubility of SLC and the passive targeting of albumin nanoparticles, they possess great potential for the treatment of acute liver damage.

Gold nanocluster-loaded hybrid albumin nanoparticles with fluorescence-based optical visualization and photothermal conversion for tumor detection/ablation

Gold nanoclusters (AuNCs) are viewed as effective hyperthermal agents for the treatment of tumors. Whereas AuNCs formed by the agglomeration of several to tens of gold atoms (<1-2 nm) possess significant fluorescence, they have a negligible hyperthermal effect, while AuNCs comprised of spherical gold nanoparticles (AuNPs > a few nanometers) have a marked hyperthermic effect but lose their inherent fluorescence and obstruct the intensity of neighboring fluorescent dyes due to Forster resonance energy transfer (FRET). To achieve both hyperthermia and fluorescence-based optical visualization, we generated hybrid albumin nanoparticles containing AuNCs (~88 nm) comprising AuNPs (~4.5 nm). We generated a series of formulated AuNCs and optimized the size, morphology, NIR absorbance (600-900 nm), hyperthermal activity, and fluorescence spectral characters of the resulting hybrid albumin nanoparticles (AuNCs/BSA-NPs) by considering the interparticle distance between the AuNPs and Cy5.5. Among these, AuNCs/BSA-NPs (formula D) had a strong hyperthermic effect and had well-preserved fluorescence intensity (from the attached Cy5.5) due to localized surface plasmon resonance (LSPR) and a reduction in FRET. These AuNCs/BSA-NPs were able to elevate the surface tumor temperature of HCT116-bearing mice to >50 °C following 808 nm laser irradiation (1.5 W/cm², 10 min), which remarkably suppressed tumor growth (17.8 ± 16.9 mm³vs. PBS and AuNCs/BSA-NPs (formula E): ~1850 and ~1250 mm³, respectively). Also, Cy5.5-modified AuNCs/BSA-NPs (formula D) showed good performance in optical fluorescence imaging of target tumors in HCT116 tumor-bearing mice. Together, our results indicate that the interparticle distance between albumin or Cy5.5 and AuNPs/AuNCs can be optimized to achieve both hyperthermia and fluorescence emission by striking a balance between LSPR and FRET effects. We believe that the AuNC/BSA-NPs formulation presented here can serve as a potential platform for both optically visualizing and treating colon cancers.

Reviewing two decades of nanomedicine implementations in targeted treatment and diagnosis of pancreatic cancer: An emphasis on state of art

Pancreatic cancer is nowadays the most life-threatening cancer type worldwide. The problem of poor diagnosis, anti-neoplastics resistance and biopharmaceutical drawbacks of effective anti-cancer drugs lead to worsen disease state. Nanotechnology-based carrier systems used in both imaging and treatment procedures had solved many of these problems. It is critical to develop advanced detection method to save patients from being too late diagnosed. Targeting the pancreatic cancer cells as well helped in decreasing the side effects associated with normal cells destruction. Drug resistance is another challenge in pancreatic cancer management that can be solved by thorough understanding of the microenvironment associated with the disease to design creative nanocarriers. This is the first article to review multifaceted approaches of nanomedicine in pancreatic cancer detection and management. Additionally, mortality rates in selected Arab and European countries were illustrated herein. An emphasis was given on therapeutic and diagnostic challenges and different nanotechnologies adopted to overcome. The four main approaches encompassed nanomedicine for herbal treatment, nanomedicine of synthetic anti-cancer drugs, metal nanoparticles as a distinct treatment policy and nanotechnology for cancer diagnosis. Future research perspectives have been finally proposed.

MSC-Delivered Soluble TRAIL and Paclitaxel as Novel Combinatory Treatment for Pancreatic Adenocarcinoma

Pancreatic cancer is the fourth leading cause of cancer death in western countries with more than 100,000 new cases per year in Europe and a mortality rate higher than 90%. In this scenario, advanced therapies based on gene therapies are emerging, thanks to a better understanding of tumour architecture and cancer cell alterations. We have demonstrated the efficacy of an innovative approach for pancreatic cancer based on mesenchymal stromal cells (MSC) genetically engineered to produce TNF-related Apoptosis Inducing Ligand (TRAIL). Here we investigated the combination of this MSC-based approach with the administration of a paclitaxel (PTX)-based chemotherapy to improve the potential of the treatment, also accounting for a possible resistance onset.

Methods: Starting from the BXPC3 cell line, we generated and profiled a TRAIL-resistant model of pancreatic cancer, testing the impact of the combined treatment in vitro with specific cytotoxicity and metabolic assays. We then challenged the rationale in a subcutaneous mouse model of pancreatic cancer, assessing its effect on tumour size accounting stromal and parenchymal organization.

Results: PTX was able to restore pancreatic cancer sensitivity to MSC-delivered TRAIL by reverting its pro-survival gene expression profile. The two compounds cooperate both in vitro and in vivo and the combined treatment resulted in an improved cytotoxicity on tumour cells.

Conclusion: In summary, this study uncovers the potential of a combinatory approach between MSC-delivered TRAIL and PTX, supporting the combination of cell-based products and conventional chemotherapeutics as a tool to improve the efficacy of the treatments, also addressing possible mechanisms of resistance.

Stearyl polyethylenimine complexed with plasmids as the core of human serum albumin nanoparticles noncovalently bound to CRISPR/Cas9 plasmids or siRNA for disrupting or silencing PD-L1 expression for immunotherapy

PURPOSE

In this study, a double emulsion method for complexing plasmids with stearyl poly-ethylenimine (stPEI) as the core to form human serum albumin (HSA) (plasmid/stPEI/HSA) nanoparticles (NPs) was developed for gene delivery by non-covalently binding onto plasmid/stPEI/HSA nanoparticles with CRISPR/Cas9 or siRNA, which disrupts or silences the expression of programmed cell death ligand-1 (PD-L1) for immunotherapy.

MATERIALS AND METHODS

Chemically synthesized stearyl-polyethyenimine (stPEI)/plasmids/HSA nanoparticles were maded by double emulsion method. They were characterized by dynamic light scattering (DLS), transmission electron microscope and also evaluated by in vitro study on CT 26 cells.

RESULTS

stPEI was synthesized by an N-(3-dimethylaminopropyl)-N-ethylcarbodiimide hydrochloride (EDC)-N-hydroxysuccinimide (NHS) reaction, and we found that the degree of substitution was ~1.0 when the ratio of PEI to stearic acid was 1:7 in the reaction. Then, two sgRNA sequences were selected and evaluated for their ability to knock out PD-L1 by decreasing its expression by about 20%. Based on the trend of particle size/zeta potential values as a function of ratio, F25P1 containing 25 μg of plasmid/stPEI/HSA NPs noncovalently bound to 1 μg plasmids via charge-charge interactions was found to be optimal. Its particle size was about 202.7±4.5 nm, and zeta potential was 12.60±0.15 mV. In an in vitro study, these NPs showed little cytotoxicity but high cellular uptake. Moreover, they revealed the potential for transfection and PD-L1 knockout in an in vitro cell model. Furthermore, F25P1S0.5 containing 25 μg of plasmid/stPEI/HSA NPs noncovalently bound to 1 μg of plasmids and 0.5 μg siRNA was prepared to simultaneously deliver plasmids and siRNA. An in vitro study demonstrated that the siRNA did not interfere with the transfection of plasmids and showed a high-transfection efficiency with a synergistic effect on inhibition of PD-L1 expression by 21.95%.

CONCLUSION

The plasmids/stPEI/HSA NPs could be a promising tool for gene delivery and improved immunotherapy.

pH Responsive Polymer Micelles Enhances Inhibitory Efficacy on Metastasis of Murine Breast Cancer Cells

A pH sensitive micellar cargo was fabricated for pH triggered delivery of hydrophobic drug paclitaxel with pH controlled drug release profiles. The size, drug loading content, and encapsulation efficiency of PTX loaded micelles were 20-30 nm, 7.5%, 82.5%, respectively. PTX loaded PELA-PBAE micelles could enhance the intracellular uptake of a model drug significantly, with increased cytotoxicity and inhibition of tumor metastasis on 4T1 cells, as confirmed by wound healing assay and tumor cells invasion assay. The expression of metastasis and apoptosis correlated proteins on 4T1 cells decreased remarkably after intervention by PTX loaded polymer micelles, as demonstrated by western blotting and quantitative reverse transcriptional-polymerase chain reaction (qRT-PCR). Our results demonstrated the pH responsive polymer micelles might have the potential to be used in the treatment of metastatic breast tumors.

Should We Keep Walking along the Trail for Pancreatic Cancer Treatment? Revisiting TNF-Related Apoptosis-Inducing Ligand for Anticancer Therapy

Despite recent advances in oncology, diagnosis, and therapy, treatment of pancreatic ductal adenocarcinoma (PDAC) is still exceedingly challenging. PDAC remains the fourth leading cause of cancer-related deaths worldwide. Poor prognosis is due to the aggressive growth behavior with early invasion and distant metastasis, chemoresistance, and a current lack of adequate screening methods for early detection. Consequently, novel therapeutic approaches are urgently needed. Many hopes for cancer treatment have been placed in the death ligand tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) since it was reported to induce apoptosis selectively in tumor cells in vitro and in vivo. TRAIL triggers apoptosis through binding of the trans-membrane death receptors TRAIL receptor 1 (TRAIL-R1) also death receptor 4 (DR4) and TRAIL receptor 2 (TRAIL-R2) also death receptor 5 (DR5) thereby inducing the formation of the death-inducing signaling complex (DISC) and activation of the apoptotic cascade. Unlike chemotherapeutics, TRAIL was shown to be able to induce apoptosis in a p53-independent manner, making TRAIL a promising anticancer approach for p53-mutated tumors. These cancer-selective traits of TRAIL led to the development of TRAIL-R agonists, categorized into either recombinant variants of TRAIL or agonistic antibodies against TRAIL-R1 or TRAIL-R2. However, clinical trials making use of these agonists in various tumor entities including pancreatic cancer were disappointing so far. This is thought to be caused by TRAIL resistance of numerous primary tumor cells, an insufficient agonistic activity of the drug candidates tested, and a lack of suitable biomarkers for patient stratification. Nevertheless, recently gained knowledge on the biology of the TRAIL-TRAIL-R system might now provide the chance to overcome intrinsic or acquired resistance against TRAIL and TRAIL-R agonists. In this review, we summarize the status quo of clinical studies involving TRAIL-R agonists for the treatment of pancreatic cancer and critically discuss the suitability of utilizing the TRAIL-TRAIL-R system for successful treatment.

Nanocarriers for TRAIL delivery: driving TRAIL back on track for cancer therapy

Since its initial identification, tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) has been shown to be capable of selectively inducing apoptosis in cancer cells. However, translation of the encouraging preclinical studies of this cytokine into the clinic has been restricted by its extremely short half-life, the presence of resistant cancer cell populations, and its inefficient in vivo delivery. Recently, there has been exceptional progress in developing novel formulations to increase the circulatory half-life of TRAIL and new combinations to treat cancers that are resistant to TRAIL. In particular, TRAIL-based nanotherapies offer the potential to improve the stability of TRAIL and prolong its half-life in plasma, to specifically deliver TRAIL to a particular target site, and to overcome resistance to TRAIL. The aim of this review is to provide an overview of the state-of-the art drug delivery systems that are currently being tested or developed to improve the biological attributes of TRAIL-based therapies.

Impact of albumin based approaches in nanomedicine: Imaging, targeting and drug delivery

A major challenge in the field of nanomedicine is to transform laboratory innovations into commercially successful clinical products. In this campaign, a variety of nanoenabled approaches have been designed and investigated for their role in biomedical applications. The advantages associated with the unique structure of albumin imparts it with the ability to interact with variety of molecules, while the functional groups present on their surface provide base for large number of modifications making it as an ideal nanocarrier system. So far, a variety of albumin based nanoenabled approaches have been intensively exploited for effective diagnosis and personalized medicine, among them some have successfully completed their journey from lab bench to marketed products. This review focuses on the recent most promising advancement in the field of albumin based nanoenabled approaches for various biomedical applications and their potential use in cancer diagnosis and therapy.

TRAIL-NP hybrids for cancer therapy: a review

Cancer is a worldwide health problem. It is now considered as a leading cause of morbidity and mortality in developed countries. In the last few decades, considerable progress has been made in anti-cancer therapies, allowing the cure of patients suffering from this disease, or at least helping to prolong their lives. Several cancers, such as those of the lung and pancreas, are still devastating in the absence of therapeutic options. In the early 90s, TRAIL (Tumor Necrosis Factor-related apoptosis-inducing ligand), a cytokine belonging to the TNF superfamily, attracted major interest in oncology owing to its selective anti-tumor properties. Clinical trials using soluble TRAIL or antibodies targeting the two main agonist receptors (TRAIL-R1 and TRAIL-R2) have, however, failed to demonstrate their efficacy in the clinic. TRAIL is expressed on the surface of natural killer or CD8+ T activated cells and contributes to tumor surveillance. Nanoparticles functionalized with TRAIL mimic membrane-TRAIL and exhibit stronger antitumoral properties than soluble TRAIL or TRAIL receptor agonist antibodies. This review provides an update on the association and the use of nanoparticles associated with TRAIL for cancer therapy.

Current status of biomarker and targeted nanoparticle development: The precision oncology approach for pancreatic cancer therapy

Pancreatic cancer remains one of the major causes of cancer-related mortality. The majority of pancreatic cancer patients are diagnosed at the advanced stage with unresectable and drug resistant tumors. The new treatments with the combination of chemotherapy, molecular targeted therapy, and immunotherapy have shown modest effects on therapeutic efficacy and survival of the patients. Therefore, there is an urgent need to develop effective therapeutic approaches targeting highly heterogeneous pancreatic cancer cells and tumor microenvironments. Recent advances in biomarker targeted cancer therapy and image-guided drug delivery and monitoring treatment response using multifunctional nanoparticles, also referred to as theranostic nanoparticles, offer a new opportunity of effective detection and treatment of pancreatic cancer. Increasing evidence from preclinical studies has shown the potential of applications of theranostic nanoparticles for designing precision oncology approaches for pancreatic cancer therapy. In this review, we provide an update on the current understanding and strategies for the development of targeted therapy for pancreatic cancer using nanoparticle drug carriers. We address issues concerning drug delivery barriers in stroma rich pancreatic cancer and the potential approaches to improve drug delivery efficiency, therapeutic responses and tumor imaging. Research results presented in this review suggest the development of an integrated therapy protocol through image-guided and targeted drug delivery and therapeutic effect monitoring as a promising precision oncology strategy for pancreatic cancer treatment.

Role of nanotechnology and gene delivery systems in TRAIL-based therapies

Since its identification as a member of the tumour necrosis factor (TNF) family, TRAIL (TNF-related apoptosis-inducing ligand) has emerged as a new avenue in apoptosis-inducing cancer therapies. Its ability to circumvent the chemoresistance of conventional therapeutics and to interact with cancer stem cells (CSCs) self-renewal pathways, amplified its potential as a cancer apoptotic agent. Many recombinant preparations of this death ligand and monoclonal antibodies targeting its death receptors have been tested in monotherapy and combinational clinical trials. Gene therapy is a new approach for cancer treatment which implies viral or non-viral functional transgene induction of apoptosis in cancer cells or repair of the underlying genetic abnormality on a molecular level. The role of this approach in overcoming the traditional barriers of radiation and chemotherapeutics systemic toxicity, risk of recurrence, and metastasis made it a promising platform for cancer treatment. The recent first Food Drug Administration (FDA) approved oncolytic herpes virus for melanoma treatment brings forth the potency of the cancer gene therapy approach in the future. Many gene delivery systems have been studied for intratumoural TRAIL gene delivery alone or in combination with chemotherapeutic agents to produce synergistic cancer cytotoxicity. However, there still remain many obstacles to be conquered for this different gene delivery systems. Nanomedicine on the other hand offers a new frontier for clinical trials and biomedical research. The FDA approved nanodrugs motivates horizon exploration for other nanoscale designed particles’ implications in gene delivery. In this review we aim to highlight the molecular role of TRAIL in apoptosis and interaction with cancer stem cells (CSCs) self-renewal pathways. Finally, we also aim to discuss the different roles of gene delivery systems, mesenchymal cells, and nanotechnology designs in TRAIL gene delivery.

An albumin nanocomplex-based endosomal pH-activatable on/off probe system

Albumin has gained considerable interest as a material for fabricating nanoparticulate systems due to its biomedical advantages, such as biocompatibility and chemical functionality. Here, we report a new pH-sensitive albumin nanocomplex prototype with a zinc-imidazole coordination bond. Albumin was conjugated with 1-(3-aminopropyl)imidazole and mPEG10kDa-NHS, and the resulting albumin conjugate (PBI) was then modified with either Cy5.5 or BHQ-3. The newly formed albumin nanocomplex (C/BQ-PBI Zn NCs: ∼116nm) system was facilely self-assembled around pH 7.4 in the presence of Zn(2+), but it quickly disassembled in an acidic environment (∼pH 5.0). Based on this pH-sensitivity, C/BQ-PBI Zn NCs emitted strong near-infrared fluorescence and released Zn(2+), turning "off" at pH ∼7.4 (e.g., plasma) and "on" at pH ∼5.0 (e.g., endo/lysosomes in tumor cells) on account of fluorescence resonance energy transfer. C/BQ-PBI Zn NCs displayed significant cytotoxicity due to an increase in cellular Zn(2+) in response to endosomal pH (∼5.0) in breast cancer MCF-7 cells and lung adenocarcinoma A549 cells. Particularly, confocal laser scanning microscopic images showed a strong fluorescence signal caused by the disassembly of C/BQ-PBI Zn NCs in the endosomal region of MCF-7 cells. Based on these results, we believe that this albumin nanocomplex is an attractive biocompatible tumor targeting probe carrier for the theranostic purpose.

Biological evaluation of PEG modified nanosuspensions based on human serum albumin for tumor targeted delivery of paclitaxel

Since its approval by the FDA, Abraxane™ has been established as a clinical standard of paclitaxel (PTX)-based therapy against a variety of cancers. Despite success, Abraxane™ is still limited by suboptimal biodistribution, unfavorable pharmacokinetics and chronic toxicities from chloroform used during preparation. Accordingly, a PTX-loaded nanosuspension based on human serum albumin (HSA) with PEG modifiers (PTX-PEG-HSA) has been developed to optimize the in-vivo biodistribution, pharmacokinetics and safety of PTX over traditional PTX-HSA nanosuspensions prepared using the accepted method for Abraxane™. Results of in-vivo pharmacokinetic (PK) studies indicated PTX-PEG-HSA achieved prolonged blood circulation, illustrated by an 8.8-fold and 4.8-fold increase in area-under-the-curve (AUC) of PTX over Taxol® and PTX-HSA, while the mean residence time (MRT) of PTX in PTX-PEG-HSA was increased by 3.2-fold and 1.5-fold, respectively. HSA mediated active targeting further suppressed non-specific distribution of PTX to normal tissues, which permitted enhanced antitumor efficacy in S180 mice over Taxol® and PTX-HSA. Safety of intravenously administered PTX-PEG-HSA was confirmed through lower hemolytic activity, a 2.2-fold and 1.2-fold increase in LD50 (113.4 mg/kg) over Taxol® and PTX-HSA alongside the absence of local venous irritation. Studies herein suggest the therapeutic and clinical applicability of PTX-PEG-HSA for tumor specific therapy.