Tumor-associated lymphatic endothelial cell promotes invasion of cervical cancer cells

The most common way for cervical cancer to spread is through the lymphatic system. Tumor-associated lymphatic endothelial cell (TLEC) has been considered to play a crucial role in metastasis of certain cancers. The aim of this study was to isolate TLEC from human cervical cancers and explore its involvement in metastasis-associated behaviors in vitro. Lymphatic vessels in 62 cervix tissue specimens ranging from cervical intraepithelial neoplasia (CIN) to advanced invasive cancer were detected using immunochemical staining with D2-40 antibody. Relation of lymphatic vessel density (LVD) to clinicopathological characters was analyzed. Primary TLECs were isolated by LYVE-1 immuno-magnetic beads from cervical cancer tissues and verified through expression of LEC markers Prox-1 and D2-40, and then cultured in vitro. Invasiveness and viability of cells were assessed by transwell assay and typan blue exclusion, respectively. Our results showed that higher LVD was significantly associated with advanced FIGO stage, pelvic lymphatic nodal metastasis (LNM), and poorer cell differentiation. TLECs were successfully primarily isolated and cultured in vitro. Supernatant of TLEC enhanced invasiveness of Hela cell, but did not significantly affect cell viability. In conclusion, TLECs might actively promote lymphatic metastasis of cervical cancer. Further studies are needed to demonstrate the underlying mechanisms.