5.

The effect of the glycosyltransferase activity of LH3 on HT-1080 cell proliferation. The cells were grown under the conditions described in experimental procedures. Student's t-test (one-tailed) was used for the statistical analysis, P< 0.05 was taken as a significant change. The changes of cell numbers deviating significantly from control cells are indicated by stars. (A) Extracellular effect in the presence of the wild-type LH3 N-terminal fragment or its glycosyltransferase-deficient form (DXD fragment) in cell medium. Untreated cells were used as controls. Significant inhibition of cell proliferation was observed with the DXD fragment-treated cells. (B) Intracellular effect by stably overexpressing full-length LH-deficient LH3 (clone H14-3). Remarkable acceleration of cell growth was seen, compared to the pcDNA3 vector (clone 9) trans-fected cells, when the glycosyltransferase activities of LH3 (not LH activity of LH3) increased in HT-1080 cells (clone H14-3).