表达Tie2基因的单核细胞研究进展

Research progress of Tie2-expressing monocytes

肿瘤血管的生成和发展在肿瘤的生长和恶化过程中起着关键作用。一类表达Tie2基因的单核细胞（TEM）通过一些生长因子和化学信号被募集到肿瘤组织中，旁分泌细胞因子促进肿瘤血管的生成和发展。TEM在促进肿瘤血管形成中起着重要作用，与血管内皮细胞祖细胞（EPC）不同的是，TEM只是在肿瘤的血管生成中起促进作用，但在肿瘤周围临近的正常组织中没有发现其存在，TEM被认为是一类肿瘤组织特异性的细胞。以TEM为载体细胞，通过TEM表达抗肿瘤药物，靶向递送的抗肿瘤药物能够有效的抑制肿瘤的生长和恶化。

Neovascularization is significant for tumor growth and progression to malignancy. Tie2 expressing monocytes （TEM） are recruited into tumors by several growth factors and chemokines, and promote tumor angiogenesis in a manner of paracrine. Moreover, TEM, while stimulating tumor angiogenesis, do not actively incorporate into blood vessels as endothelial progenitor cells （ EPC ）, but are incorporated in all newforming blood vessel. TEM were found only in tumors and were missing in non-neoplastic tissues adjacent to tumors. Novel anticancer therapies that selectively target tumors by these cells have showed significant antitumor responses and near complete abrogation of metastasis.