Studies show that caffeic acid (CA) and caffeic acid phenethyl ester (CAPE) are compounds with potent chemopreventive effects. 100 M of CAPE (only mild effect for CA). Comparing CA and CAPE activity on MDA-MB-231, CAPE clearly showed better activity for the same dosages and experiment times. 0.05; Friedman ANOVA test). After 48 h of incubation (Figure 1b,d), the CA cell viability had a dose-dependent effect with the following values: 99.0% for a dose of 10 M, 93.6% for 25 M, 89,2% for 50 M, and finally 78.0% for 100 M. However, if we compare the viability effect of CAPE vs. CA after 48 h of incubation (Figure 1b,c) the values were statistically different, starting with 71.2% for 10 M of CAPE, to 27.2% for 25 M, 9.6% for 50 M and reaching 5.6% for 100 M, the strongest cytotoxic effect. Therefore, CAPE demonstrated a high dose-dependent effect. Comparing CA vs CAPE, the cell viability values were statistically lower for CAPE (meaning CAPE has a higher cytotoxic effect than CA). Our results showed a dependent trend of dosages for both substances with CAPE being time dependent. It Rabbit Polyclonal to p47 phox (phospho-Ser359) is worth noting that CAPE reached lower viability for higher doses earlier, meaning CAPEs cytotoxic activity respectively occurs earlier. During the experiment, the half maximal inhibitory concentration (IC50) was calculated, for both substances for the MDA-MB-231 breast cancer line. The results are shown in Table 1. A 50%-mortality of breast cancer cells of MDA-MB-231 were obtained with a CAPE dose of 27.84 M for 24 h of incubation, and for 48 hC15.84 M. For CA, the values reached more than 10,000 M for 24 h and more than 1000 M during the 48 h experiments. These results show that CA has lower cytotoxic activity than CAPE on MDA-MB-231 cells during both 24 and 48 h experiments. Table 1 IC50 values (M) of CA and CAPE in relation to breast cancer MDA-MB-231 for 24 h and 48 h. The obtained data demonstrates that CAPE has far bigger activity than PR-171 inhibition CA on MDA-MB-231, during both the 24 and 48 h periods. = 3 experiments), * 0.05 value. However, after a 10 M-dose treatment of CAPE PR-171 inhibition with a control value of 92.24%, the number of live cells decreased by 62.23%. Then, respectively, the results were as follows: 49.04% at 25 M, 43.18 for 50 M, and for the highest concentration of 100 M24.85%. There was also a faster increase in the number of apoptotic cells. Early apoptotic cell number was quite stable with the dose increasing (control: 2.72%, but after dosage the values fluctuated between 9.26% and 12.51%), but the late apoptosis was significantly changed. With a control value of 3.32%, after a dosage of 10 M we obtained the value of 24.15%, for 25 MC32.85%, and a similar value of 37.29% for 50 M, and reaching 53.35% with 100 M of CAPE after 48 h. Taking into consideration, for all apoptotic cell phenotypes we observed a significant growth of the number of apoptotic cells (control total: 6.04%). Even after a CAPE treatment of 10 M, we obtained a value of 33.41%, with it reaching up to 63.76% with a dose of 100 M, for 48 h. For CA, after 24 h of experiment (Figure 2c), a significant decrease in the number of PR-171 inhibition live cells (control value: 93.03%) was also obtained in a dose dependent manner. Starting from 86.15% for 10 M of CA, PR-171 inhibition to 71.65% and 64.35% for 25 and 50 M, respectively, and finally 57.17%.