Tumor immune microenvironment-modulated nanostrategy for the treatment of lung cancer metastasis / 中华医学杂志(英文版)

As one of the most malignant tumors worldwide, lung cancer, fueled by metastasis, has shown rising mortality rates. However, effective clinical strategies aimed at preventing metastasis are lacking owing to its dynamic multi-step, complicated, and progressive nature. Immunotherapy has shown promise in treating cancer metastasis by reversing the immunosuppressive network of the tumor microenvironment. However, drug resistance inevitably develops due to inadequate delivery of immunostimulants and an uncontrolled immune response. Consequently, adverse effects occur, such as autoimmunity, from the non-specific immune activation and non-specific inflammation in off-target organs. Nanocarriers that improve drug solubility, permeability, stability, bioavailability, as well as sustained, controlled, and targeted delivery can effectively overcome drug resistance and enhance the therapeutic effect while reducing adverse effects. In particular, nanomedicine-based immunotherapy can be utilized to target tumor metastasis, presenting a promising therapeutic strategy for lung cancer. Nanotechnology strategies that boost the immunotherapy effect are classified based on the metastatic cascade related to the tumor immune microenvironment; the breaking away of primary tumors, circulating tumor cell dissemination, and premetastatic niche formation cause distant secondary site colonization. In this review, we focus on the opportunities and challenges of integrating immunotherapy with nanoparticle formulation to establish nanotechnology-based immunotherapy by modulating the tumor microenvironment for preclinical and clinical applications in the management of patients with metastatic lung cancer. We also discuss prospects for the emerging field and the clinical translation potential of these techniques.

Synthesis of acid-sensitive doxorubicin prodrug nanoparticle and its application in brain glioma treatment / 天津医药

Objective To synthesize a new kind of acid-sensitive doxorubicin prodrug nanoparticles and to evaluate its anti-brain glioma effect and efficiency through blood-brain barrier (BBB). Methods The prodrug acid-sensitive poly-ethylene glycol (PEG)-doxorubicin (PEG-DOX) copolymer was synthesized by Schiff base reaction, and PEG-DOX pro-drug nanoparticles (PEG-DOX NPs) were prepared by self-assembling. The character of PEG-DOX copolymer was detected by dynamic light scattering (DLS) instrument and 1H NMR. The morphology of PEG-DOX NPs was observed by transmission electron microscopy (TEM). The character of drug release was detected by UV mothed. The cellular uptake efficiency of glio-ma cells to PEG-DOX NPs was observed by inverted fluorescence microscope. The anti-brain glioma effects of PEG-DOX NPs and Free DOX were studied by MTT mothed. PS80-PEG-DOX NPs were gained by the modification of PEG-DOX NPs with Tween 80. Nine BALB/c mice were separated into Free DOX, PEG-DOX NPs and PS80-PEG-DOX NPs groups by ran-dom drawing lots. The mean fluorescence intensity of brain and main organs were observed by in vivo imaging system. Re-sults The copolymer of PEG-DOX can self-assemble into nanoparticles with the diameter of 100 nm. PEG-DOX NPs can quickly release DOX in acid environment. Although PEG-DOX NPs had slow cancer cell uptake than Free DOX, it had lon-ger accumulation. MTT results showed that PEG-DOX NPs had concentration dependent anti-brain glioma effect. Indepen-dent samples t-test indicated that the efficiency through BBB was significantly higher in PS80-PEG-DOX NPs group than that of Free DOX group and PEG-DOX NPs group. Conclusion PEG-DOX NPs show well anti-brain glioma effect in vi-tro, and can across BBB with high efficiency after modification, which make it possible for a potential therapeutic prodrug for brain glioma.

Synthesis and biocompatibility of ethynylated open ring derivatives of polyasparamide / 中国生化药物杂志

Objective To synthesize a new ethynylated open ring derivatives of polyasparamide as functional drug carrier.Methods L-phenylalanine methyl ester hydrochloride was prepared using L-phenylalanine and then was used for ring opening reaction of polysuccinimide.To synthesize the target product of PSI-Phe-OMe-PA, the obtained polyasparamide-g-phenylalanine derivatives ( PSI-Phe-OMe) was further ring opened by propargylamine.The structure of PSI-Phe-OMe-PA was confirmed by 1 H NMR.The biocompatibility of PSI-Phe-OMe-PA was evaluated by MTT method, inverted microscope observation and cell cycles analysis ( propidium iodide staining ) .Results The ring-opening rate of polyasparamide by L-phenylalanine methyl ester and propargylamine was 40%and 100%, respectively.All results of biocompatibility studies indicated that PSI-Phe-OMe-PA may be a good candidate for functional drug carrier.Conclusion Based on the ring-opening capability of amino-group and the specificity of click reaction, L-phenylalanine methyl ester hydrochloride and propargylamine were used successively to react with polyasparamide.PSI-Phe-OMe-PA is a biocompatible functional drug carrier.

Application of multimodal imaging in stem cell research / 中华核医学与分子影像杂志

In recent years,stem cell research has been developing quickly in biological science.As the key of regenerative medicine,stem cell therapy becomes another innovative treatment following drug therapy and surgery.In vivo stem cell tracking,including optical imaging,radionuclide imaging and MRI,can trace the viability,distribution and function of engrafted cells.Multimodal imaging integrates two or more types of imaging techniques to obtain the combined advantages of each technology,and therefore is able to accurately and effectively trace stem cell in vivo,hopefully promoting its clinical transformation.This paper reviews the application of multimodal imaging in stem cell research.

Synthesis of poly asparagine derivatives and its cytotoxicity study / 天津医药

Objective To synthesize poly asparagine derivatives and to evaluate its safety at the cellular level, which provide research platform for its potential application as drug carrier. Methods Polysuccinimide was synthesized by ther?mal polymerization of L-polyaspartic acid, and the target product of PSI-Phe-EA was obtained by the ring-opening reaction of polysuccinimide using L-phenylalanine methyl ester hydrochloride and ethanol amine. The structure of PSI-Phe-EA were characterized by 1H NMR. The rate of ring-opening of PSI was calculated by internal standard method of 1H NMR. The change of hydrophilicity was studied by the comparison of solubility. The cytotoxicity and morphology modification by PSI-Phe-EA at designate concentrations was investigated by MTT method and inverted microscopy respectively. The effects on cell cycles were analyzed by flow cytometry after propidium iodide (PI) staining. Results 1H NMR results confirmed the structure of PSI-Phe-EA and the ring-openning rate of PSI was 40%. The hydrophilicity of PSI-Phe-EA was greatly in?creased upon ring opening using ethanol amine. MTT test showed that the cell survival rates of NIH 3T3 and HepG2 cells were higher than 80%under the examined concentration (<100 mg/L). Inverted microscopy showed that 50 mg/L of PSI-Phe-EA treatment had no adverse effects on cell morphology. Cell cycle analysis indicated that PSI-Phe-EA treatment had no in?fluence on cell cycles of NIH 3T3 and HepG2 cell lines. Conclusion PSI-Phe-EA showed high hydrophilicity without sig?nificant effects on the cells survival, cells morphology and cell cycles. It is a kind of safe polymer material.