article 2019 [Vascular endothelial growth factor is up-regulated by leukemia inhibitory factor and interleukin-6 in human endometriotic stromal cells]. Zhonghua fu chan ke za zhi ·doi:10.3760/cma.j.issn.0529-567x.2019.05.007 Overexpression of LIF and IL-6 may synergistically contribute to upregulation of VEGF in ESC and promote development of endometriosis.