Microvesicles transport special proteins, micro RNA and DNA segments, which provides new access to intercellular communication. Tumor-derived membrane microvesicles ( TMV ) are involved in the tumor progress by transporting tumor-derived proteins, delivering microRNA to surrounding normal cells to alter their phenotype and promoting reverse transcription to interfere gene stability and to creat tumor microenvironment. TMV also play crucial roles in tumor angiogenesis and matrix degradation, which facilitates malignant cell metastasis. TMVs are also involved in escaping immunologicaysurveillance by intensifying the function of suppressor T cell and inducing apoptosis of cytotoxic T cells. On the other hand,microvesicles carry tumor antigens and can be used for development of tumor vaccines; some new vaccines such as AEX and DEX are under early clinical trials. Circulating microRNA and DNA segments in body fluid can be a new potential biomarker for cancer diagnosis and prognosis. Purification of microvesicles needs to be further improved, which is important for identification of microvesicles and their subtypes.%微泡(microvesicles)能运载多种特异性蛋白、微小RNA及DNA片段,其为细胞间信号交流提供了新的途径.肿瘤细胞分泌微泡(tumor-derived membrane microvesicles,TMV),而微泡参与肿瘤进展的多个方面,TMV向周围的普通细胞传递肿瘤特异性蛋白改变细胞功能,传递microRNA改变细胞表型,增加逆转录干扰基因的稳定性,从而建立肿瘤微环境；同时,其可促进血管新生、破坏细胞基质,从而增强肿瘤细胞的侵袭性；其还可通过强化抑制性免疫T细胞的功能和诱导抗肿瘤T细胞的凋亡,参与肿瘤对机体免疫监视的逃避.另外,微泡作为肿瘤抗原递呈载体,可扩大机体的抗肿瘤免疫,而由此研制的新型肿瘤疫苗,目前已处于临床试用早期阶段.循环系统中微泡运载microRNA及DNA片段的发现,为研究无创性肿瘤标志物提供新思路.然而,微泡的分离技术有待提高,这对微泡的鉴别和亚型分类有重要意义.
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