The microarray analyses showed that altogether 109 and 173 genes displayed over www.selleckchem.com/products/Bicalutamide(Casodex).html two fold difference with at least two different RPS6KB1 Inhibitors,Modulators,Libraries siRNAs in BT 474 and MCF 7 breast cancer cell lines, respectively. Of these differentially expressed genes, 68 genes were commonly down or up regulated in both cell lines including RPS6KB1, ABL1, PPP1R12B, PRKCQ, and STK32B. Sixty nine genes were down or up regulated in BT 474 with all three siRNAs, whereas ninety one genes were differentially expressed with all siRNAs in MCF 7. From these, 45 genes were differen tially expressed with all siRNAs in both of the breast can cer cell lines. Rapamycin and Ly294002 block Thr389 phosphorylation of p70S6K To further study the downstream targets of PI3K mTOR pathway, five breast cancer cell lines BT 474, MCF 7, MDA 361, MDA 436 and SK BR 3 were treated with PI3K inhibitor Ly294002 and mTOR inhibitor rapamycin.

Inhibitors,Modulators,Libraries We first evaluated the Inhibitors,Modulators,Libraries phosphorylation status of p70S6K after inhibitor treatments by Western blotting. Previously, we have shown that MCF 7, BT 474 and MDA 361 breast cancer cell lines have p70S6K amplifica tion and protein overexpression, whereas SK BR 3 show normal copy number and protein expression levels of p70S6K. After the inhibitor treatments with Ly294002 and rapamycin, significantly lower or no protein expres sion of Thr389 phosphorylated p70S6K was detected by Western blotting in all the rapamycin and Ly294002 treated breast cancer cell lines as compared to non treated samples. Our results indicate that rapamy cin and Ly294002 blocked phosphorylation of Thr389, one of the amino acids essential for p70S6K activation.

The total p70S6K levels were higher in MCF 7, MDA 361 and BT 474 breast cancer cell lines as compared to that of SK BR 3. In MDA 436 breast cancer cell line, the expression of total p70S6K was hardly Inhibitors,Modulators,Libraries detectable. Ly294002 and rapamycin treatments induce similar gene expression profiles with different biological outcomes We then studied gene expression alterations caused by inhibition of PI3K mTOR pathway by PI3K inhibitor Ly294002 and mTOR inhibitor rapamycin. SOM Inhibitors,Modulators,Libraries analysis was performed in order to detect the overall gene expres sion alterations in five inhibitor treated breast cancer cell lines. In 24 h and 48 h time point treatments, 537 and 577 genes were differentially expressed in Ly294002 treated were detected by Western immunoblotting and eIF4G1 showed downregulation at protein level by both rapamy cin and Ly294002 treatments. To evaluate the biological responses to PI3K mTOR pathway inhibi tors, cell cycle and apoptosis assays were performed for inhibitor treated breast cancer cell lines. Ly294002 treat ment caused apoptosis in BT 474 and MDA 361 and G1 arrest of the cell cycle in MCF Belinostat cost 7 and SK BR 3 breast cancer cell lines.