科研成果：黄波课题组在《cell research》 杂志发表研究论文”Reversing drug resistance of soft tumor-repopulating cells by tumor cell-derived chemotherapeutic microparticles (2016)."

细胞在凋亡或受刺激时，细胞膜能够包裹细胞内容物，形成一种被称为微颗粒（microparticle）的囊泡结构，并释放到细胞外。中国医学科学院基础医学研究所，“医学分子生物学国家重点实验室”的黄波团队从2009年开始着手微颗粒相关的研究工作，特别是细胞释放的微颗粒在炎症免疫及肿瘤方面的研究，不仅证实肿瘤细胞来源的微颗粒具有肿瘤疫苗的作用，更是发现肿瘤细胞来源的微颗粒可以作为新型载体，靶向溶瘤病毒和化疗药物。本研究所发现的载药肿瘤微颗粒逆转肿瘤再生细胞的耐药性，其机制在于肿瘤再生细胞相对于分化的肿瘤细胞更软，从而更加容易变形，并高效摄取载药微颗粒，然而微颗粒携带药物反而进入到细胞内的溶酶体（一种较大的囊泡，细胞利用它降解废物），并介导溶酶体向细胞核（类似于细胞的司令部）运动，在细胞核附件，溶酶体卸载药物，促进化疗药物的核转运。这样，囊泡和溶酶体起到轻轨运输的作用，将药物投递到肿瘤再生细胞的细胞核。这一全新机理的阐明，有望大力推动肿瘤囊泡作为天然生物载药系统的临床转化。

【摘要】：Developing novel approaches to reverse the drug resistance of tumor-repopulating cells (TRCs) or stem cell-like cancer cells is an urgent clinical need to improve outcomes of cancer patients. Here we show an innovative approach that reverses drug resistance of TRCs using tumor cell-derived microparticles (T-MPs) containing anti-tumor drugs. TRCs, by virtue of being more deformable than differentiated cancer cells, preferentially take up T-MPs that release anti-tumor drugs after entering cells, which in turn lead to death of TRCs. The underlying mechanisms include interfering with drug efflux and promoting nuclear entry of the drugs. Our findings demonstrate the importance of tumor cell softness in uptake of T-MPs and effectiveness of a novel approach in reversing drug resistance of TRCs with promising clinical applications.

相关结果已发表于《cell research》 杂志（10.1038/cr.2016.53），其作者为黄波课题组的博士后马婧薇，张一，重点室黄波教授是本文的通讯作者。该研究工作得到了以下基金的支持：The National Basic Research Program of China (2014CB542100 and 2012CB932500), the National Science Fund for Distinguished Young Scholars of China (81225021)。

Figure 1 Drug-packaging MPs target TRCs in cancer patients with malignant pleural effusion. (A) Malignant pleural effusion fluids from three end-stage lung cancer patients were collected before and after one-week treatment with intrathoracic injection of Cis-MP. A part of cells harvested from the fluids were smeared on glass slides and observed under microscope(magnification = 200×). A part of cells were stained with FITC-labeled anti-CD45 antibody and analyzed with flow cytometry.(B) Cytologic analysis of pleural effusion. The cells in pleural effusion fluids were collected and smeared on glass slides. HE staining showed abundant aggregates of neoplastic cells with conspicuous nucleoli and scanty cytoplasm (magnification =200×) before treatment. After one-week treatment, most tumor cells in the malignant fluids disappeared and abundant small immune cells were left. (C) Malignant pleural effusion fluids from three end-stage lung cancer patients were collected before and after treatment with intrathoracic injection of free Cis for one week. The pleural effusion cells were smeared on glass slides and observed under microscope (magnification = 200×). (D) Formation of spheroids of primary tumor cells cultured in 3D soft fibrin gels. CD45– tumor cells were collected from the pleural effusion fluids and seeded in soft 3D fibrin gels (1 mg/ml,gel stiffness = 90 Pa). Five days later, the spheroids were observed under microscope. Scale bar, 50 μm. (E) Treatment with conventional chemotherapeutic drugs induces TRC drug resistance; however, treatment with chemotherapeutic drug-packaging MPs reverses TRC drug resistance in cancer patients with malignant pleural effusions. See also Supplementary information,Figures S1-S4 and Table S1.