Oxalate-induced initiation of DNA synthesis in LLC-PK1 cells, a line of renal epithelial cells.

These studies examined the effects of oxalate, a constituent of renal stones, on the growth of LLC-PK1 cells. Exposure to oxalate resulted in an initiation of DNA synthesis in serum-starved, growth-arrested cells as measured by 3H-thymidine incorporation. The effects of oxalate were comparable to those observed in response to 10% serum. Moreover, exposure to oxalate plus 10% serum stimulated DNA synthesis to a greater extent than oxalate or serum alone. These studies indicate that oxalate promotes the progression of cells from the G0/G1 to the S phase of the cell cycle. However, the increase in DNA synthesis was not always followed by an increase in cell number since high concentrations of oxalate led to a reduction in cell number.