HLM006474 is a pan E2F inhibitor, which inhibits E2F4 DNA-binding with an IC50 of 29.8 µM in A375 cells. IC50: 29.8 µM (E2F4 DNA-binding)[1]
HLM006474 shows little activities against E2F4 DNA-binding in A375 cells at 10 and 20 µM, apparently inhibits E2F4 DNA-binding at 40 µM, and increasingly suppressses the effect at 60 and 80 µM concentrations. HLM006474 (40 µM) inhibits E2F4 activity via suppression of its DNA-binding activity and down regulation of its expression. HLM006474 (40 µM) also significantly induces apoptosis in A375 and 231 cell lines for 24 hours. HLM006474 dramaticly reduces cyclin D3 protein expression, and is a potent inducer of PARP cleavage[1]. HLM006474 reduces the viability of both SCLC and NSCLC lines with IC50 ranging from 15 to 75 µM. HLM006474 (60 µM) increases the expression of several known E2F-regulated genes after short treatments in H292 and H1299 cell lines. HLM006474 (20 µM) weakly synergizes with paclitaxel, but there is antagonism between HLM006474 and cisplatin and gemcitabine in H1299 cells[2]. HLM006474 leads to a decrease in the mRNA levels of MAD2. Furthmore, HLM006474 apparently suppresses the increase of Mad2 protein and pRb-S780 signal but not the level of Skp2 protein in human lung cancer A549 cellss[3].
[1]. Ma Y, et al. A small-molecule E2F inhibitor blocks growth in a melanoma culture model. Cancer Res. 2008 Aug 1;68(15):6292-9. [2]. Kurtyka CA, et al. E2F inhibition synergizes with paclitaxel in lung cancer cell lines. PLoS One. 2014 May 15;9(5):e96357.