For two groups proliferation and stress response the overrepresentation is very highly sig nificant. selleck 17-DMAG Regulation of 13 genes representing the 6 functional cate gories, apoptosis, proliferation, general Inhibitors,Modulators,Libraries growth, signaling transport, metabolism and others, were verified by real time RT PCR from independent samples to confirm the regula tion of genes connected to the major cellular effects observed. The cellular effects of the functional groups regulated by black cohosh are summarized in Figure 4. Expression val ues of selected genes are presented in Table 2. A complete list of all regulated genes is available. The data discussed in this publication have also been deposited in NCBIs Gene Expression Omnibus. and are accessible through GEO Series accession number GSE6800.

Proliferation In agreement with the anti proliferative effect of the black cohosh extract, genes involved in proliferation control were significantly overrepresented. Transcripts related to cell cycle regulation Inhibitors,Modulators,Libraries and DNA replication were regulated in a manner supporting cell cycle Inhibitors,Modulators,Libraries arrest. Genes, whose products are involved in the transition from G1 to S phase appeared to be downregulated, such as cyclins, cyclin dependent kinase 2 and transcription Inhibitors,Modulators,Libraries regulators, whereas Inhibitors,Modulators,Libraries transcription of inhibitory genes cyclin G2, GADD45A and p21cip1 was increased. Elevated levels of CCNG2, cyclin B1 interacting protein 1, forkhead box O3A, GADD45A and p21cip1 genes as well as down regulation of cyclin A2 and CDK2 provided evi dence that cell cycle progression might be additionally arrested at the G2 M checkpoint.

The level of various DNA replication related genes was also reduced, thereby suggesting a reduction in the replication rate. All cell cycle related effects are sum marized in Figure 5, which shows a cell cycle diagram from GenMAPP. in which up and downregulated genes are marked. Apoptosis In addition to the regulation of genes certainly involved in prolifer ation control, we also observed regulation of apoptosis linked genes in a pro apoptotic manner, indicating that the extract could sensitize breast cancer cells for apoptotic events. An increase in apoptotic events would also con Proliferation assay Effects on growth rate of MCF 7 cells tribute to the decrease in cellular proliferation observed. In cells treated with black cohosh the transcript of the apoptosis inhibitor survivin was downregulated, whereas genes cod ing for apoptosis inducing and supporting products were increased. FOXO3A, GADD45A, GDF 15 and p21cip1, whose mRNA levels increased, are also connected with apoptosis in addition to their role in cell cycle control. Transcript of tyrosyl tRNA synthetase, whose secretion is linked to apoptotic events. was upregulated.