Summarize your findings on the impact of risky behavior on your well-being by referring to the following spheres of well-being:
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-emotional
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Nature Communications
Nature Publishing Group
Hollow boron nitride nanospheres as boron reservoir for prostate cancer treatment
Xia Li, Xiupeng Wang, [...], and Dmitri Golberg
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Abstract
High global incidence of prostate cancer has led to a focus on prevention and treatment strategies to reduce the impact of this disease in public health. Boron compounds are increasingly recognized as preventative and chemotherapeutic agents. However, systemic administration of soluble boron compounds is hampered by their short half-life and low effectiveness. Here we report on hollow boron nitride (BN) spheres with controlled crystallinity and boron release that decrease cell viability and increase prostate cancer cell apoptosis. In vivo experiments on subcutaneous tumour mouse models treated with BN spheres demonstrated significant suppression of tumour growth. An orthotopic tumour growth model was also utilized and further confirmed the in vivo anti-cancer efficacy of BN spheres. Moreover, the administration of hollow BN spheres with paclitaxel leads to synergetic effects in the suppression of tumour growth. The work demonstrates that hollow BN spheres may function as a new agent for prostate cancer treatment.
Prostate cancer is one of the most common cancers for males, particularly in the developed Western countries1. The high global incidence of prostate cancer has led to a focus on prevention and treatment strategies to reduce the public health impact of the disease2,3,4,5,6. For prostate cancer, the main clinical treatments include active surveillance, surgery7, radiation therapy8, hormone therapy9 and chemotherapy10 with drugs, such as paclitaxel (PTX) and docetaxel. An epidemiological study shows that boron (B) intake can reduce the risk of prostate cancer11,12 for human by up to 54% (ref. 13). Boric acid (BA), the dominant form of B in plasma, has been tested as a preventative and therapeutic agent against prostate cancer. For example, in vitro BA inhibits the proliferation of prostate cancer cells in a dose-dependent manner14. In the animal model, BA decreases serum prostate-specific antigen (PSA) levels by 88%, inhibits the LNCap tumour growth by 38% and reduces insulin-like growth factor-1 in nude mice injected with human LNCap prostate cancer cells15. Mechanisms of B-mediated anticancer action in prostate cancer include the reduction of intracellular calcium signals and storage, the decrease in enzymatic activities (serine protease, NAD-dehydrogenases and so on) and the inhibition of the cancer cell proliferation14,16,17,18,19.
Recently, B compounds have attracted attention as preventative and therapeutic agents for prostate cancer and other cancers11,12,13,14,15,16,17,19,20,21,22,23,24,25,26,27. However, systemic administration of soluble B compounds, such as BA, associates with the drawbacks of its short half-life period, low bioavailability, requirement of frequent administration, low fraction arrived in the tumour site and limited effectiveness for prostate cancer treatments. Moreover, the therapeutic window of BA for prostate cancer cells, which is ∼100 times higher than its average serum level in human, suggests difficulty in systemic administration of soluble B compounds without toxicity14,21,23. Local delivery of anticancer drug or agents in a sustained manner either to the region that contains a tumour or directly within the tumour has the advantage of increasing tumour exposure to drug while limiting systemic toxicity28,29. Therefore, local delivery of a sparsely soluble B-containing compound, as an alternative to soluble B compounds, might hold promise as a preventative and therapeutic agent for prostate cancer treatment. In addition, the systematic administration of a sparsely soluble B-containing compound in a nanoparticle format can facilitate the passive targeting of drugs into the tumour sites, decrease the side effects and enhance the antitumour efficacy with the aid of enhanced permeability and retention effects30. Typically, the sparsely soluble B-containing compound is boron nitride (BN) that is structurally analogous to carbon. To date, BN has been used as a delivery vehicle31,32,33 for anticancer drugs such as doxorubicin, similarly to other nano delivery vehicles, such as carbon nanotubes34, graphene35, mesoporous silica36, calcium phosphate37 and polymers38. However, there have been no reports regarding the effectiveness of BN itself in cancer treatments.
Herein we fabricated hollow BN spheres with controlled crystallinity and solubility to guide B release