A Review of Mesoporous Silica Nanoparticle Delivery Systems in Chemo-Based Combination Cancer Therapies.

Chemotherapy is an important anti-tumor treatment in clinic to date, however, the effectiveness of traditional chemotherapy is limited by its poor selectivity, high systemic toxicity, and multidrug resistance. In recent years, mesoporous silica nanoparticles (MSNs) have become exciting drug delivery systems (DDS) due to their unique advantages, such as easy large-scale production, adjustable uniform pore size, large surface area and pore volumes. While mesoporous silica-based DDS can improve chemotherapy to a certain extent, when used in combination with other cancer therapies MSN based chemotherapy exhibits a synergistic effect, greatly improving therapeutic outcomes. In this review, we discuss the applications of MSN DDS for a diverse range of chemotherapeutic combination anti-tumor therapies, including phototherapy, gene therapy, immunotherapy and other less common modalities. Furthermore, we focus on the characteristics of each nanomaterial and the synergistic advantages of the combination therapies. Lastly, we examine the challenges and future prospects of MSN based chemotherapeutic combination therapies.

Modified nanoscale metal organic framework-based nanoplatforms in photodynamic therapy and further applications.

Photodynamic therapy (PDT) has emerged as a modality in cancer treatment because it is less invasive and highly selective compared with conventional chemotherapy and radiation therapy. Nanoscale metal organic frameworks (nMOFs) have exhibited great potential for use in constructing nanoplatforms for improved PDT because of their unique structural advantages such as large surface areas, high porosities, tunable compositions and various other modifications. The large majority of current nMOF-based systems employ specific modifying groups to overcome the deficiencies previously observed when using older nMOFs in PDT. In this review, we summarize modifications to these systems such as enhancing singlet oxygen generation by introducing photoactive agents, alleviating tumor hypoxia and engineering active targeting abilities. The applications of MOF-based nanoparticles in synergistic cancer therapies that include PDT, as well as in theranostics are also discussed. Finally, we discuss some of the challenges faced in this field and the future prospects for the use of nMOFs in PDT.

[Synthesis and cell biological properties of polyaspartic acid drug/gene vector].

OBJECTIVE: Taking polysuccinimide as the main chain, amine side chain and alkyl side chain were grafted to prepare the drug/gene co-delivery vector. The property of the polymers with various side links were investigated to select an optimal vector. METHODS: Poly-D, L-polysuccinimide was synthesized by polymerization reaction of D, L-aspartic acid as monomer. Therefore, N, N-dimethylenedipropyl-triamine and 3, 3'-diaminodipropylamine were grafted with dodecylamine/adecylamine/octadecylamine at different proportions by ring-opening reaction to obtain amphiphilic PEECs. The structure of the material was confirmed by 1H NMR; the particle size and surface potential of the micelles were measured by dynamic light scattering; the critical micelle concentration (CMC) was determined by pyrene fluorescent probe; the RNA blocking ability was characterized by agarose gel electrophoresis; the release behavior of the PEECs was examined and the cytotoxicity, cellular uptake and gene silencing efficiency of the PEECs were studied at the cellular level. RESULTS: A series of PEECs with different grafting rates was successfully synthesized. The particle sizes and surface potential of the PEEC derived micelles were between 250 nm and 350 nm and 27 mV and 45 mV, respectively, with a small CMC value. The RNA binding ratio of PEECs was at a mass ratio of about 0.8:1. MTT assay demonstrated that PEEC micelles had certain cytotoxicity. PEECs had excellent micelle formation, drug-loading and gene binding abilities, particularly, PEEC16-2 showed high gene silencing efficiency at the cellular level. CONCLUSIONS: PEECs are able to co-delivery drug and gene, and PEEC16-2 micelles have the best ability of drug encapsulation and gene delivery.