Pseudolaric Acid A

Pseudolaric Acid A is more sensitive to leukemia P-388 and melanoma SK-MEL5, suggesting it deserves further development as potentially useful antitumor agent.^[2]

KB screen: The KB cells are maintained on Roswell Park Memorial Institute (RMPI) 1640 media supplemented with 5 % fetal calf serum and 100 µg/ml kanamycin. The cells (5 x 10⁴cell/ml) are plated 24 hours before the addition of Pseudolaric Acid A. All counting of KB cells is done on a hemacytometer. Results are expressed as the dose that inhibits growth to 50 % of control growth by three days after drug addition. P-388 and L-1210 screens: The P-388 lymphocytic leukemia and L- 1210 lymphoid leukemia cells are maintained in minimum essential medium (MEM) plus 10% fetal calf serum and 100 µg/ml penicillin/ streptomycin. Cells (10⁴) are incubated with Pseudolaric Acid A prepared in 0.05 % tween-80 NaCI. Cells are counted in control and treated tubes on day 3 using a hemacytometer. A-549, HCT-8 screens: Media used for the propagation and growth of these cell lines are F-12 with 10% fetal calf serum (FCS) for A-549, RPMI-1640 with sodium pyruvate and 10 % horse serum for HCT- 8. All media are treated with 50 ng/ml of gentocin to prevent bacterial contamination. The cells are grown in a humidified atmosphere of 5% CO2 and 95% air at 37℃. 24-well tissue culture plates are seeded each well with approximately 1 x 10⁴cells per 2 ml of growth medium and incubated at 37℃ overnight. The starting cell numbers in quadruplicate wells are determined by dispersing the monolayer with trypsin-EDTA solution and the total number of cells per well is determined. Pseudolaric Acid A in suitable concentration are added to quadruplicate wells in order to achieve a maximum treatment dosage of 10 µg/ml. After further incubation of the tissue culture plates at 37℃ for 72 h, the cell numbers in each well are determined.