Inhibition of attachment and chemotactic invasion of uterine endometrial cancer cells by a new vinca alkaloid, conophylline

The effect of conophylline, a new vinca alkaloid that inhibits ras expression, on tumor cell adhesion and infiltration was evaluated using a human endometrial cancer cell line. When SNG-II, a highly differentiated human endometrial cancer cell line, was exposed to conophylline, the cells developed filamentous processes at concentrations which did not affect cell proliferation (0.03-0.3 μg/ml). After exposure to conophylline (0.3 μg/ml), cells adherent to matrigel- and type IV collagen-coated wells respecively decreased to 26.9% and 33.3% of the number in the untreated control culture (p < 0.01). In an in vitro invasion assay using a Boyden chamber, infiltration of cells exposed to conophylline decreased to 19.4% (0.3 μg/ml) (p < 0.01) of the control. In a wound assay, conophylline inhibited the movement of cells at 24 hr after wounding. Flow cytometric analysis revealed that expression of integrin β₁ was not altered by conophylline, but E-cadherin and CD44 were decreased. The expression of E-cadherin and CD44 could be changed by conophlline.