Everolimus, as a derivative of rapamycin

by Selleckchem | Oct 08 2012

CHARACTERIZATION OF EVEROLIMUS
The PI3K/Akt/mTOR pathway plays a important role in various cellular processes including cell growth, proliferation, survival, and metabolism. is found to be constitutively activated in multiple tumor cells, providing potential targets for anticancer therapy. Everolimus, also known as RAD001, is a potent and highly specific mTOR inhibitor. Everolimus, together with Temsirolimus, are both important derivatives of Rapamycin. Everolimus structure reveals that it is an immunosuppressive macrolide [1] bearing a stable 2-hydroxyethyl chain substitution at position 40 on the rapamycin structure. Everolimus has the solubility around 192 mg/mL in both dimethyl sulfoxide (DMSO) and ethanol, however it is scarcely soluble in water. And the approximate price of Everolimus is $670 per 100 mg in selleckchem.com and Everolimus price may vary according to the proportion purity of the preparation and/or from one Everolimus supplier to different ones.

IN VITRO ACTIVITIES
According to the existing results from kinase assays, Everolimus, as a derivative of Rapamycin, shows the inhibition activity against mTOR (FKBP12) with IC50 ranging from 1.6 nM to 2.4 nM. [2] In vitro, Everolimus exhibits immunosuppressive activity by inhibiting growth factor-driven cell proliferation of a lymphoid cell line and of vascular smooth muscle cells. [3] Proliferation assay indicates that Everolimus for 96 hours inhibits cell proliferation of tumor cell lines in a dose-dependent manner, including the HL cell lines L1236 and L540cy and the ALCL cell lines (Karpas 299 (ALK+) and FE-PD (ALK-)). The following flow cytometry analysis suggests that Everolimus treatment blocks cell-cycle progression in G0/G1 phase without effects on cell apoptosis and thus leads to the failure to expand in cell numbers. [4] The related mechanism has also been studied. The results show, Everolimus treatment downregulates the truncated isoform of the transcription factor C/EBP-beta, and leads to disruption of terminal differentiation as well as induction of a transformed phenotype. In addition, Everolimus also inhibits constitutive NF-kappaB activity, which is a critical survival factor in HL cells. [4] As regards for anti-tumor effects on solid cancer, the mTOR inhibitor Everolimus is indicated to induces antiproliferative and proapoptosis effects in human pancreatic neuroendocrine tumor cell lines that exhibits constitutively activated PI3K/Akt/mTOR signaling. [5]

IN VIVO ACTIVITIES
Similar with in vitro study results, Everolimus also shows both anti-tumor and immunosuppressive activity in vitro. Mouse xenografts inoculated with human ovarian cancer cells SKOV-3 reveals that Everolimus inhibits tumor growth, angiogenesis, and i.p. dissemination and ascites production and prolongs survival. [6] Additionally, Everolimus (1-5 mg/kg/d orally) is also evaluated for antitumor activity in combination with other drugs using mice bearing subcutaneous human H-596 lung, KB-31 cervical, or HCT-116 colon tumor xenografts. The results indicate that combination treatment of cisplatin, doxorubicin, paclitaxel, or patupilone with everolimus results in cooperative antitumor effects, in some cases producing regressions without significant increases in toxicity. [7] These studies support the potential clinical use of Everolimus as a partner for conventional cytotoxics.

REFERENCES
[1] Majewski M, et al. Proc Natl Acad Sci U S A. The immunosuppressive macrolide RAD inhibits growth of human Epstein-Barr virus-transformed B lymphocytes in vitro and in vivo: A potential approach to prevention and treatment of posttransplant lymphoproliferative disorders. 2000, 97(8), 4285-4290.
[2] Sedrani R, et al. Chemical modification of rapamycin: the discovery of SDZ RAD. Transplant Proc, 1998, 30(5), 2192-2194.
[3] Schuler W, et al. Transplantation. SDZ RAD, a new rapamycin derivative: pharmacological properties in vitro and in vivo. 1997, 64(1), 36-42.
[4] Jundt F, et al. A rapamycin derivative (everolimus) controls proliferation through down-regulation of truncated CCAAT enhancer binding protein {beta} and NF-{kappa}B activity in Hodgkin and anaplastic large cell lymphomas. Blood. 2005, 106(5), 1801-1807.
[5] Zitzmann K, et al. The novel mTOR inhibitor RAD001 (everolimus) induces antiproliferative effects in human pancreatic neuroendocrine tumor cells. Neuroendocrinology. 2007, 85(1), 54-60.
[6] Mabuchi S, et al. RAD001 inhibits human ovarian cancer cell proliferation, enhances cisplatin-induced apoptosis, and prolongs survival in an ovarian cancer model. Clin Cancer Res. 2007, 13(14), 4261-4270.
[7] O'Reilly T, et al. Evaluation of the mTOR inhibitor, everolimus, in combination with cytotoxic antitumor agents using human tumor models in vitro and in vivo. Anticancer Drugs. 2011, 22(1), 58-78.

Cat.No.	Product Name	Information
S1120	Everolimus	Everolimus is an mTOR inhibitor of FKBP12 with IC50 of 1.6-2.4 nM in a cell-free assay. Everolimus induces cell apoptosis and autophagy and inhibits tumor cells proliferation.
S1044	Temsirolimus	Temsirolimus is a specific mTOR inhibitor with IC50 of 1.76 μM in a cell-free assay. Temsirolimus induces autophagy and apoptosis.
S1039	Rapamycin	Rapamycin is a specific mTOR inhibitor with IC50 of ~0.1 nM in HEK293 cells.Rapamycin binds to FKBP12 and specifically acts as an allosteric inhibitor of mTORC1. Rapamycin is an autophagy activator and an immunosuppressant.
S1166	Cisplatin	Cisplatin is an inorganic platinum complex, which is able to inhibit DNA synthesis by conforming DNA adducts in tumor cells. Cisplatin activates ferroptosis and induces autophagy.Solutions are unstable and should be fresh-prepared.DMSO is not recommended to dissolve platinum-based drugs, which can easily lead to drug inactivation.
S1208	Doxorubicin (DOX) HCl	Doxorubicin (DOX) HCl is an antibiotic agent that inhibits human DNA topoisomerase I and topoisomerase II with IC50s of 0.8 μM and 2.67 μM, respectively. Doxorubicin reduces basal phosphorylation of AMPK. Doxorubicin is used in the concomitant treatment of HIV-infected patients but is found to be at high risk of HBV reactivation.This product may precipitate when dissolved in PBS solution. It is recommended to prepare the stock solution in pure water and dilute with either pure water or saline to obtain the working solution.Doxorubicin (Adriamycin) HCl can be used to induce animal models of kidney disease.
S1150	Paclitaxel	Paclitaxel is a microtubule polymer stabilizer with IC50 of 0.1 pM in human endothelial cells.Paclitaxel can cause both mitotic arrest and apoptotic cell death. Paclitaxel also induces autophagy.