诱导多能性干细胞源性巨噬细胞极化状态调控上皮性卵巢癌转移能力机制的研究

Metastasis and resistance to chemotherapy often lead to the unsuccessfulness of the treatment of ovarian cancer, the first killer in gynecological tumors. Tumor-associated macrophages (TAM), also known as M2d macrophages, play an important role in ovarian cancer metastasis. With the high stability in genome, TAM has been highlighted as an ideal target for ovarian cancer. But, both phenotype and functions change along with the microenvironment, making it difficult to study the interaction between tumor cells and TAM. Regenerative medicine and cell therapy research has been focused on induced pluripotent stem cells (iPSCs). In our previous study, we successfully established a feeder-free differentiation systems through which iPSCs would be directed differentiated into monocytes and then high-purity phenotypically stable M1, M2 macrophages. In the current study we will use this differentiation system to study the mechanisms of macrophage polarization state regulating metastasis in epithelial ovarian cancer, including the impact on epithelial-mesenchymal transition, anoikis, etc. And then we will further use the tet-on system to turn off the expression of M-CSF receptor when differentiating into macrophages, to push macrophage polarization into M1 direction and study whether metastasis in ovarian cancer can be inhibited. The successful implementation of this project will help to clarify the role and significance of macrophages in ovarian cancer metastasis, and provide some experimental evidence for the possibility of using human iPSCs source macrophage in cell therapy.

卵巢癌多因复发转移和化疗耐药导致治疗效果不理想，死亡率居妇科肿瘤之首。肿瘤相关巨噬细胞（TAM）为M2d型巨噬细胞，在卵巢癌转移中发挥重要作用。巨噬细胞基因组稳定性高，是卵巢癌治疗的理想靶点。由于TAM在改变微环境后表型和功能均发生变化，目前缺少研究TAM与肿瘤细胞相互作用的理想体系。诱导多能性干细胞（iPSCs）是近几年再生医学和细胞治疗研究的重点和热点。我们前期工作已成功建立了人iPSCs定向向单核巨噬细胞方向分化体系，以获得大量高纯度表型稳定的M1、M2型巨噬细胞。本课题将运用该体系并结合tet-on蛋白表达系统阐明对上皮性卵巢癌转移的调控机制，包括对上皮间质转化和失巢凋亡等方面的作用，以揭示iPSCs来源巨噬细胞极化状态抑制卵巢癌转移的调控作用与机理，本课题的成功实施将有助于阐明巨噬细胞在卵巢癌转移中的作用和意义，为探索使用人iPSCs来源巨噬细胞进行细胞治疗的可能性提供实验基础。

卵巢癌多因复发转移和化疗耐药导致治疗效果不理想，死亡率居妇科肿瘤之首。肿瘤相关巨噬细胞（TAM）为M2d型巨噬细胞，在卵巢癌转移中发挥重要作用。巨噬细胞基因组稳定性高，是卵巢癌治疗的理想靶点。由于TAM在改变微环境后表型和功能均发生变化，目前缺少研究TAM与肿瘤细胞相互作用的理想体系。诱导多能性干细胞（iPSCs）是近几年再生医学和细胞治疗研究的重点和热点。我们前期工作已成功建立了人iPSCs定向向单核巨噬细胞方向分化体系，以获得大量高纯度表型稳定的M1、M2型巨噬细胞。在此基础上，我们从临床观察、动物模型、体外细胞培养着手，进一步探索其相关机制，探讨巨噬细胞极化情况对于卵巢癌侵袭转移能力的影响及其相关机制。本研究结果提示：M2型巨噬细胞通过促进上皮间质转化、基质金属蛋白酶分泌、局部黏着斑激酶表达及抑制肿瘤细胞凋亡等机制促进肿瘤的进展。同时，卵巢癌细胞通过上调CD47的表达抑制巨噬细胞的吞噬作用从而逃逸免疫监视。通过敲低CD47的表达或者使用抗CD47单克隆抗体能够促进巨噬细胞吞噬肿瘤细胞从而达到抗肿瘤作用。卵巢癌干细胞的CD47表达水平比肿瘤细胞更高，使用抗CD47单克隆抗体可以促进巨噬细胞杀伤肿瘤干细胞。该研究成果为卵巢癌的免疫治疗提供了实验理论依据，为以巨噬细胞活化为机制的免疫治疗奠定了理论基础。