Dual ligand-targeted Pluronic P123 polymeric micelles enhance the therapeutic effect of breast cancer with bone metastases

Bone metastasis secondary to breast cancer negatively impacts patient quality of life and survival.The treatment of bone metastases is challenging since many anticancer drugs are not effectively delivered to the bone to exert a therapeutic effect.To improve the treatment efficacy,we developed Pluronic P123(P123)-based polymeric micelles dually decorated with alendronate(ALN)and cancer-specific phage protein DMPGTVLP(DP-8)for targeted drug delivery to breast cancer bone metastases.Doxorubicin(DOX)was selected as the anticancer drug and was encapsulated into the hydrophobic core of the micelles with a high drug loading capacity(3.44%).The DOX-loaded polymeric micelles were spherical,123 nm in diameter on average,and exhibited a narrow size distribution.The in vitro experiments demonstrated that a pH decrease from 7.4 to 5.0 markedly accelerated DOX release.The micelles were well internalized by cultured breast cancer cells and the cell death rate of micelle-treated breast cancer cells was increased compared to that of free DOX-treated cells.Rapid binding of the micelles to hydroxyapatite(HA)microparticles indicated their high affinity for bone.P123-ALN/DP-8@DOX inhibited tumor growth and reduced bone resorption in a 3D cancer bone metastasis model.In vivo experiments using a breast cancer bone metastasis nude model demonstrated increased accumulation of the micelles in the tumor region and considerable antitumor activity with no organ-specific histological damage and minimal systemic toxicity.In conclusion,our study provided strong evidence that these pH-sensitive dual ligand-targeted polymeric micelles may be a successful treatment strategy for breast cancer bone metastasis.

Efficacy and safety of radiotherapy combined with zoledronic acid in the treatment of lung cancer with bone metastasis: a meta-analysis

Objective: To evaluate the efficacy and safety of radiotherapy combined with zoledronic acid fOr the treatment of bone metastases. Methods: Use Pubmed, Cochrane Library, Embase, CBM, CNKI, Wanfang, Weipu tools to search-related databases at home and abroad. From 2013.1 to March 2019, radiotherapy combined with zoledronic acid and radiotherapy alone for bone metastasis of lung cancer were collected. Experimental studies;quality evaluation and data extraction for each of the included studies, and Cochrane risk bias assessment tools for quality evaluation of the literature. Data processing was performed using RevMan 5.3 and Stata 15.0 software, including risk ratio (OR), 95% CI, I2, and P values. Line sensitivity test, publication bias evaluation is using Egger's, Bgge's method quantitative calculation using Revman 5.3 and Stata 15.0 software for statistical analysis. Results: The total of 8 articles was included, and the number of cases was 703. The results of the meta-analysis showed that the radiotherapy, combined with the zoledronic acid group was effective in the treatment of lung cancer with bone metastasis. The meta-analysis was Z = 6.31 (P < 0.00001), OR (95% CI = 3.57, (2.41, 5.30)), the difference was statistically significant. The combined effect of bone metastases was better than that of the single-stage group. The meta-analysis results were Z = 3.18 (P = 0.001) and OR (95% CI = 3.21, (1.57, 6.59)), indicating the therapeutic effect of the two groups in the treatment of bone metastases. The difference is statistically significant. Adverse reactions include: (1) bone marrow suppression, blood toxicity;(2) fever and rash;(3) nausea, vomiting, and fatigue;(4) liver damage and loss of appetite, meta-analysis results are: bone marrow suppression, blood toxicity: Z =0.73 ( P = 0.47), OR (95% CI = 0.58 (0.13, 2.54));fever, rash: Z = 0.36 (P = 0.36), OR (95% CI = 1.3 (0.31, 5.38));nausea, vomiting, Weakness: Z = 0.29 (P = 0.77), OR (95% CI = 0.85 (0.27, 2.62));liver function damage and loss of appetite: Z = 0.00 (P = 1.00), OR (95% CI = 1.00 (0.17, 6.00)). The P values of the four meta-analyses were all greater than 0.05, and the difference was not statistically significant, indicating that the addition of zoledronic acid to the bone metastasis of lung cancer did not aggravate the changes of the above four adverse reactions. Conclusion: Radiotherapy combined with the zoledronic acid group is better than the single radiotherapy group in treating pain caused by bone metastasis. It can effectively treat bone metastasis and will not aggravate the occurrence of adverse reactions.

A nanoagent for concurrent therapy of breast cancer bone metastasis and cancer-induced bone pain through SLC7A11 interruption and photodynamic therapy

Bone metastasis,a life-threatening complication of advanced breast cancer,is often accompanied by debilitating pain(cancer-induced bone pain,CIBP)that severely impairs life quality and survival.The concurrent treatment of bone metastases and CIBP remains a clinical challenge because the therapeutic options are limited.In this study,we construct a near-infrared light-activated nano-therapeutic system to meet this conundrum.In detail,sorafenib(SRF)and photosensitizer(chlorin e6,Ce6)are encapsulated into mesoporous hydroxyapatite nanoparticles(HANPs),which are further functionalized with hyaluronic acid(HA)to obtain HA-SRF/Ce6@HANPs system.The designed nanoplatform destroys tumor cells in vitro and in vivo via the synergism of SRF(interrupting the exchange of cystine/glutamate by inhibiting SLC7A11)and photodynamic therapy(PDT,inducing reactive oxygen species generation).The decrease in tumor burden and reduction of extracellular glutamate significantly attenuate CIBP in mice model with developing bone cancer.Moreover,the combination of HA-SRF/Ce6@HANPs and PDT inhibit osteoclasts activation,promote osteoblast differentiation and accelerate bone repair.Overall,the nanoagent with good biocompatibility may provide an effective therapy method for the concurrent treatment of breast cancer bone metastasis and CIBP.

Brucine Inhibits Bone Metastasis of Breast Cancer Cells by Suppressing Jagged1/Notch1 Signaling Pathways

Objective： To examine the effects of brucine on the invasion, migration and bone resorption of receptor activator of nuclear factor-kappa B ligand（RANKL）-induced osteoclastogenesis. Methods： The osteoclastogenesis model was builded by co-culturing human breast tumor MDA-MB-231 and mouse RAW264.7 macrophages cells. RANKL（50 ng/m L） and macrophage-colony stimulating factor（50 ng/m L） were added to this system, followed by treatment with brucine（0.02, 0.04 and 0.08 mmol/L）, or 10 μmol/L zoledronic acid as positive control. The migration and bone resorption were measured by transwell assay and in vitro bone resorption assay. The protein expressions of Jagged1 and Notch1 were investigated by Western blot. The expressions of transforming growth factor-β1（TGF-β1）, nuclear factor-kappa B（NF-κB） and Hes1 were determined by enzyme-linked immunosorbent assay. Results： Compared with the model group, brucine led to a dose-dependent decrease on migration of MDA-MB-231 cells, inhibited RANKL-induced osteoclastogenesis and bone resorption of RAW264.7 cells（P 〈0.01）. Furthermore, brucine decreased the protein levels of Jagged1 and Notch1 in MDA-MB-231 cells and RAW264.7 cells co-cultured system as well as the expressions of TGF-β1, NF-κB and Hes1（P〈0.05 or P〈0.01）. Conclusion： Brucine may inhibit osteoclastogenesis by suppressing Jagged1/Notch1 signaling pathways.