Cancer cell membrane-cloaked mesoporous silica nanoparticles with a pH-sensitive gatekeeper for cancer treatment.

Nanoparticular drug delivery system (NDDS) has great potential for enhancing the efficacy of traditional chemotherapeutic drugs. However, it is still a great challenge to fabricate a biocompatible NDDS with simple structure capable of optimizing therapeutic efficacy, such as high tumor accumulation, suitable drug release profile (e.g. no premature drug leakage in normal physiological conditions while having a rapid release in cancer cells), low immunogenicity, as well as good biocompatibility. In this work, a simple core/shell structured nanoparticle was fabricated for prostate cancer treatment, in which a mesoporous silica nanoparticle core was applied as a container to high-efficiently encapsulate drugs (doxorubicin, DOX), CaCO3 interlayer was designed to act as sheddable pH-sensitive gatekeepers for controlling drug release, and cancer cell membrane wrapped outlayer could improve the colloid stability and tumor accumulation capacity. In vitro cell experiments demonstrated that the as-prepared nanovehicles (denoted as DOX/MSN@CaCO3@CM) could be efficiently uptaken by LNCaP-AI prostate cancer cells and even exhibited a better anti-tumor efficiency than free DOX. In addition, Live/Dead cell detection and apoptosis experiment demonstrated that MSN/DOX@CaCO3@CM could effectively induce apoptosis-related death in prostate cancer cells. In vivo antitumor results demonstrated that DOX/MSN@CaCO3@CM administration could remarkably suppress the tumor growth. Compared with other tedious approaches to optimize the therapeutic efficacy, this study provides an effective drug targeting system only using naturally biomaterials for the treatment of prostate cancer, which might have great potential in clinic usage.

[Hypothermia combined with dexamethasone reduces ICAM1 expression and protects spermatogenesis after testicular torsion-detorsion].

OBJECTIVE: To investigate the protective effect of hypothermia combined with dexamethasone on spermatogenesis and the expression of intercellular adhesion molecule 1 (ICAM1) after testicular torsion-detorsion. METHODS: We made unilateral testicular torsion models in 100 pubertal male Sprague-Dawley rats by 720 degree torsion of the left testis and then randomly divided them into four groups of equal number to be treated with normal temperature + physiological saline (group A), hypothermia + physiological saline (group B), normal temperature + dexamethasone (group C), and hypothermia + dexamethasone (group D). After 48 hours, we collected the testes, observed pathological changes of the testicular tissue by HE staining under the light microscope, detected the apoptosis of spermatogenic cells by TUNEL, and determined the expression of ICAM1 by Western blot. RESULTS: HE staining showed different degrees of testicular tissue injury in the four groups of rats, most obvious in group A, but mild in the other three. The ICAM1 protein expression was significantly higher in group A (0.68 +/-0. 03) than in B (0. 49 +/- 0. 06, P <0. 05) , C (0. 46 +/- 0. 09, P < 0.05) , and D (0.17 +/- 0.08, P <0.01). The nuclei were deep brown or brown. Lots of apoptotic spermatogenic cells were seen in the torsion testis of group A, with a significantly higher apoptosis index ( [33. 13 +/- 3.21 ]%) than in B ( [ 17. 12 +/-5.23 ]%, P < 0.05), C ([14.13 +/- 2.03]%, P <0.05), and D ([9.05 +/- 1.03]%, P <0.01). CONCLUSION: Hypothermia combined with dexamethasone can protect the testis from injury as well as the reproductive function of the testis after testicular torsion-detorsion and reduce the expression of ICAM1.