Synergistic strategy with hyperthermia therapy based immunotherapy and engineered exosomes-liposomes targeted chemotherapy prevents tumor recurrence and metastasis in advanced breast cancer.

Advanced breast cancer with recurrent and distal organ metastasis is aggressive and incurable. The current existing treatment strategies for advanced breast cancer are difficult to achieve synergistic treatment of recurrent tumors and distant metastasis, resulting in poor clinical outcomes. Herein, a synergistic therapy strategy composed of biomimetic tumor-derived exosomes (TEX)-Liposome-paclitaxel (PTX) with lung homing properties and gold nanorods (GNR)-PEG, was designed, respectively. GNR-PEG, with well biocompatibility, cured recurrent tumors effectively by thermal ablation under the in situ NIR irradiation. Meanwhile, GNR-mediated thermal ablation activated the adaptive antitumor immune response, significantly increased the level of CD8+ T cells in lungs and the concentration of serum cytokines (tumor necrosis factor-α, interlekin-6, and interferon-γ). Subsequently, TEX-Liposome-PTX preferentially accumulated in lung tissues due to autologous tumor-derived TEX with inherent specific affinity to lung, resulting in a better therapeutic effect on lung metastasis tumors with the assistance of adaptive immunotherapy triggered by GNR in vivo. The enhanced therapeutic efficacy in advanced breast cancer was a combination of thermal ablation, adaptive antitumor immunotherapy, and targeted PTX chemotherapy. Hence, the synergistic strategy based on GNR and TEX-Liposome provides selectivity to clinical treatment of advanced breast cancer with recurrent and metastasis.

Sequential Dual Delivery System Based on siCOX-2-Loaded Gold Nanostar and Thermal-Sensitive Liposomes Overcome Hypoxia-Mediated Multidrug Resistance in Tumors.

Reversing hypoxia-mediated multidrug resistance (MDR) presents a unique challenge in clinical chemotherapy. Here, a sequential dual delivery system composited with Cyclooxygenase-2 siRNA (siCOX-2) in poly-d-arginine (9R)/2-deoxyglucose (DG)-loaded gold nanostar (GNS) (siCOX-2@RDG) and paclitaxel (PTX)-loaded thermosensitive liposome (PTSL) was proposed to conquer the hypoxia-mediated MDR in tumors. As a result, the prepared siCOX-2@RDG exhibited a starlike morphology with a uniform particle size of 194.36 ± 1.44 nm and a ζ-potential of -11.83 ± 2.01 mV. In vitro, PTSL displayed expected thermal-responsive release properties. As expected, siCOX-2@RDG displayed exceptional DG-mediated hypoxia-targeting capability both in vitro and in vivo and downregulated the expression of COX-2 successfully. Meanwhile, GNS-triggered hyperthermia elevated the cellular uptake of PTSL in PTX-resistant HepG2(HepG2/PTX) cells in vitro and enhanced the permeability of tumor tissues, thus elevating the valid retention of PTX into solid tumors. Finally, we demonstrated that the sequential dual systems composed of siCOX-2@RDG and PTSL could reverse hypoxia-mediated MDR and exhibit excellent synergistic antitumor effects both in vitro and in vivo, prolonging the survival of tumor-bearing mice. The devised sequential dual systems, composed of two independent nanosystems, have a promising potential to overcome hypoxia-mediated MDR in clinical practice.

Virus Mimetic Shell-Sheddable Chitosan Micelles for siVEGF Delivery and FRET-Traceable Acid-Triggered Release.

Targeting vascular endothelial growth factor (VEGF) using small interfering RNA (siVEGF) has shown great potential in inhibiting the growth, proliferation, and migration of tumors by reducing the proliferation of blood vessels. On the basis of bionic principles, a novel pH-responsive and virus mimetic shell-sheddable chitosan (CS) micelles (CMs) as siRNA delivery system was introduced in this study. The cyclo(Arg-Gly-Asp-d-Phe-Lys) (cRGD) modified poly(enthylene glycol) (PEG) was conjugated to the HA2 modified chitosan via a hydrazone linkage (cRGD-PEG-Hz-CS-HA2). The cRGD-PEG-Hz-CS-HA2 conjugate could form micelles by interacting with the complex of octanal, Boc-l-lysine, and 9-d-arginine (9R) (octyl-Lys-9R) as a hydrophodic core forming agent, termed as cRGD-PEG-Hz-CS-HA2/octyl-Lys-9R (abbreviated as cRGD/HA2/Hz-CMs).The CMs modified with cRGD can accurately target glioma cells (U87MG cells) with high expression of αvß3. The payloads of siVEGF were packed into the core of cRGD/HA2/Hz-CMs via electrostatic interaction and hydrophobic interaction. The intracellular cargo release was achieved by the pH-responsive lysis of the hydrazone bond in acidic environment of endosome. Moreover, the exposed HA2, as a pH-sensitive membrane-disruptive peptide, assists the escape of the carriers from endosome into cytosol. In addition, cRGD/HA2/Hz-CMs can effectively deliver siVEGF and silence VEGF gene expression in U87MG cells, leading to the significant tumor growth inhibition. This study demonstrates that cRGD/HA2/Hz-CMs can deliver and release siVEGF in a controlled manner, which was traced by the fluorescence resonance energy transfer (FRET) system in order to achieve RNAi-based anti-angiogenic treatment of cancer in vivo.

Exosome-mediated siRNA delivery to suppress postoperative breast cancer metastasis.

High recurrence and metastasis of triple-negative breast cancer (TNBC) after operation is a leading cause of breast cancer related death. The pre-metastatic niche (PMN) is an environment in a secondary organ conducive to the metastasis of a primary tumor. Herein, we identify exosomes from autologous breast cancer cells that show effective lung targeting ability. Based on this, we developed the biomimetic nanoparticles (cationic bovine serum albumin (CBSA) conjugated siS100A4 and exosome membrane coated nanoparticles, CBSA/siS100A4@Exosome) to improve drug delivery to the lung PMN. CBSA/siS100A4@Exosome self-assembled nanoparticles formed homogeneous sizes of ~200 nm, protected siRNA from degradation, and showed excellent biocompatibility. Further in vivo studies showed that CBSA/siS100A4@Exosome had a higher affinity toward lung in comparison to the CBSA/siS100A4@Liposome, and exhibited outstanding gene-silencing effects that significantly inhibited the growth of malignant breast cancer cells. Taken together, these results indicate that CBSA/siS100A4@Exosome self-assembled nanoparticles are a promising strategy to suppress postoperative breast cancer metastasis.

Combined Modality Therapy Based on Hybrid Gold Nanostars Coated with Temperature Sensitive Liposomes to Overcome Paclitaxel-Resistance in Hepatic Carcinoma.

In this study, we prepared gold nanostar (GNS) composite nanoparticles containing siRNA of cyclooxygenase-2(siCOX-2) that were modified by tumor targeting ligand 2-deoxyglucose (DG) and transmembrane peptide 9-poly-D-arginine (9R) to form siCOX-2(9R/DG-GNS). Paclitaxel loaded temperature sensitive liposomes (PTX-TSL) were surface-modified to produce PTX-TSL-siCOX-2(9R/DG-GNS) displaying homogeneous star-shaped structures of suitable size (293.93 nm ± 3.21) and zeta potentials (2.47 mV ± 0.22). PTX-TSL-siCOX-2(9R/DG-GNS) had a high thermal conversion efficiency under 808 nm laser radiation and a superior transfection efficiency, which may be related to the targeting effects of DG and increased heat induced membrane permeability. COX-2 expression in HepG2/PTX cells was significantly suppressed by PTX-TSL-siCOX-2(9R/DG-GNS) in high temperatures. The co-delivery system inhibited drug-resistant cell growth rates by ≥77% and increased the cell apoptosis rate about 47% at elevated temperatures. PTX-TSL and siCOX-2 loaded gold nanostar particles, therefore, show promise for overcoming tumor resistance.

[Clinical observation of 100 patients with malignant lymphoma treating with different preconditioning regimens followed by autologous hematopoietic stem cell transplantation].

This study was designed to compare the curative effect, prognosis and safety of different preconditioning regimens for patients who received autologous hematopoietic stem cell transplantation (AHSCT) for malignant lymphoma (ML). The clinical data of 100 ML patients (Sep 1992 to Aug 2010 in 307 Hospital) were retrospectively analyzed, and were divided into two groups by different preconditioning regimens: the high-dose chemotherapy preconditioning group and high-dose chemotherapy/radiotherapy preconditioning group. The overall survival (OS) rate, progress free survival (PFS) rate and adverse effect were analyzed. The results showed that until Feb 2011, the median follow-up was 33.5 months. All patients were engrafted and their hematopoiesis was reconstituted. The median time of WBC recovery up to > 1.0×1.0(9)/L in high-dose chemotherapy preconditioning group and high-dose chemotherapy/radiotherapy preconditioning group were (6.0 ± 0.4) d and (8.2 ± 0.4) d, platelet up to > 20.0×1.0(9)/L in two groups were (7.1 ± 0.8) d and (11.4 ± 2.5) d (P < 0.05). The 3-year OS rate of the two groups were 67.3% and 68.9%. 5-year OS rates of two groups were 62.8% and 60.6%, 10-year OS rates of two groups were 57.6% and 56.2% respectively; 3-year PFS of two group were 63.6% and 63.2%, 5-year of two group were 59.4% and 58.3%, 10-year of two group were 50.8% and 55.3% respectively (P > 0.05). Meanwhile, the incidence of fever, infection, bleeding, secondary cancer between two groups was not significant different (P > 0.05). It is concluded that the hematopoietic reconstitution of high-dose chemotherapy/radiotherapy preconditioning group is later than that of high-dose chemotherapy preconditioning group. However, there is no significant difference in curative effect and prognosis between the two groups.