Modeling the interaction of amphiphilic polymer nanoparticles with biomembranes to Guide rational design of drug delivery systems

Nanoparticle assisted drug delivery to the cytoplasm is limited by sequestration of nanoparticles in endosomes. Endosomal escape through polymer-induced membrane destabilization is one of a few well characterized mechanisms to overcome it. Aiming to utilize this method in vivo, it is necessary to understand how modulating the structural and chemical features of the polymer and the presence of proteins in biological fluids can affect this activity. Here, as a model for the endosomal membrane, we use the membrane of red blood cells to evaluate the membrane destabilization ability of a model amphiphilic polymer in the presence of blood plasma using a hemolysis assay. This allows determination of red blood cells membrane permeabilization through the quantification of hemoglobin leakage. Our results showed a strong inhibitory effect of plasma, and that hemolytic activity can be improved by chemical modification of the polymeric micelle, reducing its interaction with plasma proteins. Finally, a second mechanism of pH-induced direct diffusion is proposed and tested using an oil/water partitioning model. These results offer a body of knowledge to improve delivery of drugs across biological membranes using carefully designed polymeric nanocarriers.

Co-administration of H-ferritin-doxorubicin and Trastuzumab in neoadjuvant setting improves efficacy and prevents cardiotoxicity in HER2 + murine breast cancer model

Neoadjuvant chemotherapy has been established as the standard of care for HER2-positive breast cancer since it allows cancer down-staging, up to pathological complete response. The standard of care in the neoadjuvant setting for HER2-positive breast cancer is a combination of highly cytotoxic drugs such as anthracyclines and the anti-HER2 monoclonal antibody. Despite this cocktail allows a pathological complete response in up to 50%, their co-administration is strongly limited by intrinsic cardiotoxicity. Therefore, only a sequential administration of anthracyclines and the anti-HER2 treatment is allowed. Here, we propose the anthracycline formulation in H-Ferritin nanocages as promising candidate to solve this unmet clinical need, thanks to its capability to increase anthracyclines efficacy while reducing their cardiotoxicity. Treating a murine model of HER2-positive breast cancer with co-administration of Trastuzumab and H-Ferritin anthracycline nanoformulation, we demonstrate an improved tumor penetration of drugs, leading to increased anticancer efficacy and reduced of cardiotoxicity.

Magnetic Refrigeration with Recycled Permanent Magnets and Free Rare-Earth Magnetocaloric La-Fe-Si

Magnetic refrigeration is an upcoming technology that could be an alternative to the more than 100-year-old conventional gas-vapor compression cooling. Magnetic refrigeration might answer some of the global challenges linked with the increasing demands for readily available cooling in almost every region of the world and the global-warming potential of conventional refrigerants. Important issues to be solved are, for example, the required mass and the ecological footprint of the rare-earth permanent magnets and the magnetocaloric material, which are key parts of the magnetic cooling device. The majority of existing demonstrators use Nd-Fe-B permanent magnets, which account for more than 50% of the ecological footprint, and Gd, which is a critical raw material. This work shows a solution to these problems by demonstrating the world's first magnetocaloric demonstrator that uses recycled Nd-Fe-B magnets as the magnetic field source, and, as a Gd replacement material, La-Fe-Mn-Si for the magnetocaloric heat exchanger. These solutions show that it is possible to reduce the ecological footprint of magnetic cooling devices and provides magnetic cooling as a green solid-state technology that has the potential to satisfy the rapidly growing global demands.

Thirty Years of Cancer Nanomedicine: Success, Frustration, and Hope

Starting with the enhanced permeability and retention (EPR) effect discovery, nanomedicine has gained a crucial role in cancer treatment. The advances in the field have led to the approval of nanodrugs with improved safety profile and still inspire the ongoing investigations. However, several restrictions, such as high manufacturing costs, technical challenges, and effectiveness below expectations, raised skeptical opinions within the scientific community about the clinical relevance of nanomedicine. In this review, we aim to give an overall vision of the current hurdles encountered by nanotherapeutics along with their design, development, and translation, and we offer a prospective view on possible strategies to overcome such limitations.

Imatinib-loaded gold nanoparticles inhibit proliferation of fibroblasts and macrophages from systemic sclerosis patients and ameliorate experimental bleomycin-induced lung fibrosis

Interstitial lung involvement in Systemic Sclerosis (SSc-ILD) is a complication with high morbidity and mortality. Specifically, engineered gold nanoparticles (GNPs) are proposed as targeted delivery system increasing efficacy of drugs with antifibrotic effect, such as tyrosine kinases. We aimed to test in vitro and in vivo the activity of targeted Imatinib (Im)-loaded GNP on SSc-ILD patients derived cells and in experimental model of lung fibrosis. GNPs functionalized with anti-CD44 and loaded with Im (GNP-HCIm) were synthesized. Lung fibroblasts (LFs) and alveolar macrophages from bronchoalveolar lavage fluids of SSc-ILD patients were cultured in presence of nanoparticles. GNP-HCIm significantly inhibited proliferation and viability inducing apoptosis of LFs and effectively reduced IL-8 release, viability and M2 polarization in alveolar macrophages. Anti-fibrotic effect of tracheal instilled GNP-HCIm was evaluated on bleomycin lung fibrosis mouse model comparing effect with common route of Im administration. GNP-HCIm were able to reduce significantly lung fibrotic changes and collagen deposition. Finally, electron microscopy revealed the presence of GNPs inside alveolar macrophages. These data support the use of GNPs locally administered in the development of new therapeutic approaches to SSc-ILD.

Does conjugation strategy matter? Cetuximab-conjugated gold nanocages for targeting triple-negative breast cancer cells

The efficient targeting of cancer cells depends on the success of obtaining the active targeting of overexpressed receptors. A very accurate design of nanoconjugates should be done via the selection of the conjugation strategy to achieve effective targeted nanoconjugates. Here, we present a detailed study of cetuximab-conjugated nonspherical gold nanocages for the active targeting of triple-negative breast cancer cells, including MDA-MB-231 and MDA-MB-468. A few different general strategies were selected for monoclonal antibody conjugation to the nanoparticle surface. By varying the bioconjugation conditions, including antibody orientation or the presence of a polymeric spacer or recombinant protein biolinker, we demonstrate the importance of a rational design of nanoconjugates. A quantitative study of gold content via ICP-AES allowed us to compare the effectiveness of cellular uptake as a function of the conjugation strategy and confirmed the active nature of nanoparticle internalization in cancer cells via epidermal growth factor receptor recognition, corroborating the importance of the rational design of nanomaterials for nanomedicine.

Are nanotechnological approaches the future of treating inflammatory diseases?

The current treatments for chronic inflammatory diseases cause severe side effects due to nonspecific drug accumulation. Nanotechnology opens the way to new therapeutic strategies that exploit the ability of immune cells, and especially of phagocytes, to internalize nanoparticles. The cellular uptake of nanoparticles requires specific interactions and is affected by the chemical and physical properties of the carriers. Therefore, optimizing these properties is crucial for designing nanodrugs for immunotherapy. In perspective, we discuss the nanoparticle-based approaches that have been proposed to induce tolerance in autoimmune disorders and lessen the symptoms of inflammatory diseases.

Multifunctional Magnetic Gold Nanomaterials for Cancer

The integration of multiple imaging and therapeutic agents into a customizable nanoplatform for accurate identification and rapid prevention of cancer is attracting great attention. Among the available theranostic nanosystems, magnetic gold nanoparticles are particularly promising as they exhibit unique physicochemical properties that can support multiple functions, including cancer diagnosis by magnetic resonance imaging, X-ray computed tomography, Raman and photoacoustic imaging, drug delivery, and plasmonic photothermal and photodynamic therapies. This review gives an overview of recent advances in the fabrication of multifunctional gold nanohybrids with magnetic and optical properties and their successful demonstration in multimodal imaging and therapy of cancer. Concerns around toxicity of these nanomaterials are also discussed in view of an imminent transition to clinical practice.

Abstract P1-20-04: Nanoformulation of doxorubicin inside H- ferritin nanocages allows a cardio-safe combined therapy with trastuzumab: De-escalating cardiotoxicity in HER2-positive breast cancer

Background: HER2+ breast cancer (BC) accounts for 20-25 % of BCs and it is characterized by high aggressiveness.1 Despite the anti-HER2 monoclonal antibody Trastuzumab (TZ) has improved BC clinical outcome, it could induce severe cardiac reversible dysfunction:2 HER2 signaling is also essential for growth and survival of myocardiocytes.3 Therefore, the concurrent use of TZ with other cardiotoxic drugs as doxorubicin (DOX) is discouraged.3 Both neoadjuvant and adjuvant clinical trials have challenged the notion that TZ should be administered with anthracyclines only sequentially,4 despite pre-clinical studies demonstrated the significant enhancement of efficacy by their coadministration.5-7 Nanomedicine answers to this clinical issue with HFn-DOX: a natural protein-based DOX nanoformulation with native tumor targeting capability that displays a self-triggered nuclear delivery of DOX improving antitumor efficacy and reducing both chemoresistance and cardiotoxicity.8

Methods: HER2+ BC bearing mice have been treated 5 times twice a week with placebo, HFn-DOX (1 mg/Kg, i.v.), TZ (5 mg/Kg, i.p.) and with the combination of them. Main end-point were cardiotoxicity and anticancer efficacy. Tumor size was measured by caliper, while antitumor activity and cardiotoxicity were characterized by ICH, immunofluorescence, cytofluorimetry, TEM, mass spectrometry and western blot on resections. Statistical analyses were conducted using two-tailed Student's t-test (P< 0.05)

Results: Although single treatments with HFn-DOX or TZ display a good capability to reduce tumor progression, their combination improves antitumor potential, affecting tumor size and angiogenesis. Since the main TZ activity is the induction of the Antibody-Dependent Cell mediated Cytotoxicity, we have assessed the effect of HFn-DOX on Tumor Infiltrating Lymphocytes (TIL), revealing that both TILs enumeration and TIL activity is unaffected by HFn-DOX. On the other hand, HFn-DOX increases the induction of apoptosis, suggesting that the reduction of the tumor size observed in mice treated with the combination of TZ and HFn-DOX is attributable to the coupling of these activity. Mitochondrial morphology has been checked for cardiotoxicity. A pathological increase in mitochondria area coupled with cristae depletion has been evidenced only in mice treated with TZ alone, confirming the overall safety of the HFn-DOX formulation. Interestingly, mice treated with the TZ and HFn-DOX did not display evidences of cardiac suffering. TZ quantification in tumor and heart revealed that the combination with HFn-DOX couples the increased TZ accumulation and penetration in tumor with TZ reduction in heart, resulting in the lack of cardiotoxicity.

Conclusions: Our results suggest that a combined therapy with HFn-DOX and TZ allows an enhanced anticancer activity and reduced cardiotoxicity, with potential translational implications on the treatment of HER2+ BC patients.

[1] Nat Rev Cancer 2009; 9:463; [2] Nat. Med. 2012; 18(11):1639; [3] Cancer treatments reviews 2009; 35:633; [4] The breast 2014; 23:317; [5] Cancer Res. 1998; 58(13):2825; [6] Lancet Oncol. 2011; 12(3):236; [7] Lancet 2010; 375(9712):377. [8] Oncotarget. 2017; 8:8383.

Citation Format: Mazzucchelli S, Andreata F, Bonizzi A, Monieri M, Bellini M, Longhi E, Ottria R, Sorrentino L, Truffi M, Prosperi D, Zerbi P, Corsi F. Nanoformulation of doxorubicin inside H- ferritin nanocages allows a cardio-safe combined therapy with trastuzumab: De-escalating cardiotoxicity in HER2-positive breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-20-04.

Abstract P4-06-09: Withdrawn

This abstract was withdrawn by the authors.

Citation Format: Corsi F, Andreata F, Truffi M, Sorrentino L, D'Addio F, Monieri M, Gambaro A, Bellini M, Prosperi D, Mazzucchelli S. Withdrawn [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-06-09.

Pemetrexed-loaded nanoparticles targeted to malignant pleural mesothelioma cells: an in vitro study

PURPOSE

Malignant pleural mesothelioma (MPM) is an aggressive tumor characterized by poor prognosis. Its incidence is steadily increasing due to widespread asbestos exposure. There is still no effective therapy for MPM. Pemetrexed (Pe) is one of the few chemotherapeutic agents approved for advanced-stage disease, although the objective response to the drug is limited. The use of gold nanoparticles (GNPs) as a drug delivery system promises several advantages, including specific targeting of malignant cells, with increased intracellular drug accumulation and reduced systemic toxicity, and, in the case of MPM, direct treatment administration into the pleural space. This study aims at exploring CD146 as a potential MPM cell-specific target for engineered Pe-loaded GNPs and to assess their effectiveness in inhibiting MPM cell line growth.

METHODS

MPM cell lines and primary cultures obtained by pleural effusions from MPM patients were assayed for CD146 expression by flow cytometry. Internalization by MPM cell lines of fluorescent dye-marked GNPs decorated with a monoclonal anti CD146 coated GNPs (GNP-HC) was proven by confocal microscopy. The effects of anti CD146 coated GNPs loaded with Pe (GNP-HCPe) on MPM cell lines were evaluated by cell cycle (flow cytometry), viability (MTT test), clonogenic capacity (soft agar assay), ROS production (electric paramagnetic resonance), motility (wound healing assay), and apoptosis (flow cytometry).

RESULTS

GNP-HC were selectively uptaken by MPM cells within 1 hour. MPM cell lines were blocked in the S cell cycle phase in the presence of GNP-HCPe. Both cell viability and motility were significantly affected by nanoparticle treatment compared to Pe. Apoptotic rate and ROS production were significantly higher in the presence of nanoparticles. Clonogenic capacity was completely inhibited following nanoparticle internalization.

CONCLUSION

GNP-HCPe treatment displays in vitro antineoplastic action and is more effective than Pe alone in inhibiting MPM cell line malignant phenotype. The innovative use of specifically targeted GNPs opens the perspective of local intrapleural administration to avoid normal cell toxicity and enhance chemotherapy efficacy.

Half-Chain Cetuximab Nanoconjugates Allow Multitarget Therapy of Triple Negative Breast Cancer

The use of therapeutic monoclonal antibodies (mAbs) has revolutionized cancer treatment. The conjugation of mAbs to nanoparticles has been broadly exploited to improve the targeting efficiency of drug nanocarriers taking advantage of high binding efficacy and target selectivity of antibodies for specific cell receptors. However, the therapeutic implications of nanoconjugation have been poorly considered. In this study, half-chain fragments of the anti-EGFR mAb cetuximab were conjugated to colloidal nanoparticles originating stable nanoconjugates that were investigated as surrogates of therapeutic mAbs in triple negative breast cancer (TNBC). Three TNBC cell lines were selected according to EGFR expression, which regulates activation of MAPK/ERK and PI3K/Akt pathways, and to distinctive molecular profiling including KRAS, PTEN, and BRCA1 mutations normally associated with diverse sensitivity to treatment with cetuximab. The molecular mechanisms of action of nanoconjugated half-chain mAb, including cell targeting, interference with downstream signaling pathways, proliferation, cell cycle, and apoptosis, along with triggering of ADCC response, were investigated in detail in sensitive and resistant TNBC cells. We found that half-chain mAb nanoconjugation was able to enhance the therapeutic efficacy and improve the target selectivity against sensitive, but unexpectedly also resistant, TNBC cells. Viability assays and signaling transduction modulation suggested a role of BRCA1 mutation in TNBC resistance to cetuximab alone, whereas its effect could be circumvented using half-chain cetuximab nanoconjugates, suggesting that nanoconjugation not only improved the antibody activity but also exerted different mechanisms of action. Our results provide robust evidence of the potential of half-chain antibody nanoconjugates in the treatment of TNBC, which could offer a new paradigm for therapeutic antibody administration, potentially allowing improved curative efficiency and reduced minimal effective dosages in both sensitive and resistant tumors.

Recent advances in magnetic fluid hyperthermia for cancer therapy

Recently, magnetic fluid hyperthermia using biocompatible magnetic nanoparticles as heat mediators for cancer therapy has been extensively investigated due to its high efficiency and limited side effects. However, the development of more efficient heat nanomediators that exhibit very high specific absorption rate (SAR) value is essential for clinical application to overcome the several restrictions previously encountered due to the large quantity of nanomaterial required for effective treatment. In this review, we focus on the current progress in the development of magnetic nanoparticles based hyperthermia therapy as well as combined therapy harnessing hyperthermia with heat-mediated drug delivery for cancer treatment. We also address the fundamental principles of magnetic hyperthermia, basics of magnetism including the effect of several parameters on heating capacity, synthetic methods and nanoparticle surface chemistry needed to design and develop an ideal magnetic nanoparticle heat mediator suitable for clinical translation in cancer therapy.

A fast and straightforward procedure for vault nanoparticle purification and the characterization of its endocytic uptake

BACKGROUND

Vaults are eukaryotic ribonucleoprotein particles composed of up 78 copies of the 97 kDa major vault protein that assembles into a barrel-like, "nanocapsule" enclosing poly(ADP-ribose) polymerase, telomerase-associated protein-1 and small untranslated RNAs. Overall, the molecular mass of vault particles amounts to about 13 MDa. Although it has been implicated in several cellular functions, its physiological roles remain poorly understood. Also, the possibility to exploit it as a nanovector for drug delivery is currently being explored in several laboratories.

METHODS

Using the baculovirus expression system, vaults were expressed and purified by a dialysis step using a 1 MDa molecular weight cutoff membrane and a subsequent size exclusion chromatography. Purity was assessed by SDS-PAGE, transmission electron microscopy and dynamic light scattering. Particle's endocytic uptake was monitored by flow cytometry and confocal microscopy.

RESULTS

The purification protocol here reported is far simpler and faster than those currently available and lead to the production of authentic vault. We then demonstrated its clathrin-mediated endocytic uptake by normal fibroblast and glioblastoma, but not carcinoma cell lines. In contrast, no significant caveolin-mediated endocytosis was detected.

CONCLUSIONS

These results provide the first evidence for an intrinsic propensity of the vault complex to undergo endocytic uptake cultured eukaryotic cells.

GENERAL SIGNIFICANCE

The newly developed purification procedure will greatly facilitate any investigation based on the use of the vault particle as a natural nanocarrier. Its clathrin-mediated endocytic uptake observed in normal and in some tumor cell lines sheds light on its physiological role.

Heteronanoparticles by Self-Assembly of Ecdysteroid and Doxorubicin Conjugates To Overcome Cancer Resistance

Heteronanoparticles (H-NPs) consisting of conjugates characterized by a squalene tail linked to doxorubicin and ecdysteroid derivatives are presented. Biological evaluation on A2780ADR cell line confirms not only the maintenance of the activity of the parental drug but also the ability to overcome cancer resistance. The in vitro cell uptake was demonstrated, and the involvement of an endosomal-mediated pathway was suggested.