[LDH, SDH assay for the effect of freezing on MEC-1, Ca9-22, Tca8113 cell lines in vitro]

Three human oral cancer cell lines were tested with the purpose of investigating the effect of freezing temperature and freeze-thaw cycle on the cells by LDH-release, SDH assay. The results showed that freezing can kill the cancer cells. The effective freezing temperature for cryonecrosis of the cells was -40 degrees C-(-)50 degrees C. Two freeze-thaw cycles were potent enough to obtain the most effectual cryonecrosis of the cancer cell lines. Amount of LDH-release was freezing-temperature dependent. At -40 degrees C, more then 90% LDH of cells were released. The results showed that the membranes of 90% survival cells were injured after cryotreat.