Involvement of H type 1 carbohydrate antigen in cell adhesion to vascular endothelial cells of human endometrial cancer

A number of previously published studies have suggested that blood-group-related carbohydrate antigens, expressed on cancer cell membranes, may be related to the cytobiological characteristics (invasiveness, metastasizing potential, etc.) of cancer. In our previous study, we divided SNG-II, a human endometrial cancer cell line, into SNG-S and SNG-W and compared their properties. In that study, we found that H type l carbohydrate antigen, which is scarcely expressed on SNG-S but strongly expressed on SNG-W, may play a significant role in the adhesion of SNG-W to vascular endothelial cells. In the present study, we clarified in some detail, the relationship between H type 1 carbohydrate antigen and endothelial cell adhesion, and also compared the propensity for hematogenous metastasis of these two cell lines in vivo. The following results were obtained: 1. The adhesion of SNG-W to human umbilical vein endothelial cells (1), was inhibited in a concentration - dependent manner by the addition of ont H type 1 monoclonal antibody. 2. In the How cytometric analysis using single carbohydrate - conjugated fluorescent beads, it was shown that H type 1 carbohydrate-attached beads adhered to HUVECs. On the other hand, beads conjugated with Lewis^a, Lewis^b, or H type 2 carbohydrate antigen did not adhere to HUVECs. 3. In an in vivo study using a nude mouse model of lung metastasis, SNG-W was found to show a significantly greater propensity for blood-borne metastasis than SNG-S. These results suggest that the H₁ carbohydrate antigen expressed on the cancer cell membrane serves as an adhesion factor for vascular endothelial cells, and that endometrial cancer expressing high levels of this antigen has a high propensity for blood- borne metastasis, suggesting that the expression of this antigen on the cancer cells may serve as an indicator of poor prognosis.