2010;6:1863C1881. on inhibition of MTOC amplification, -tubulin induction and Taxol level of resistance. Comparing to Fulvestant (FST), ER- specific inhibitor, this chemical can block the cortisol/cortisone-induced MTOC deregulation as well as ER- signaling. Our results suggest that stress hormone induced tumorigenesis would be achieved by MTOC amplification, and CSH1 would be useful for prevention of stress-hormone or steroid hormone-induced chromosomal instability. has been used for a long time to treat various kinds of human diseases including cancer and kidney malfunction [21, 22]. Recently, isolated ginsenoisdes has been reported to be effective on immune system . However, molecular biological working mechanism of ginsenosides on human cancer has not been revealed until now. Thus, it would be meaningful to verify the working mechanism and the effect of ginsenosides on human cancer. This study is focused on tumorigenic effect of stress hormone, in particular MTOC amplification and drug resistance. In addition, since several ginsenosides possess stress hormone-related chemical structure, favorable effect of ginsenoisde on MTOC amplification and Taxol resistance is investigated. RESULT Stress hormones provide taxol resistance Since stress hormone, cortisol and its related hormones (cortisone and aldosterone) are commonly originated from cholesterol and show similar chemical structure with estrogen (Supplementary Figure S1A), their biological effect on Taxol-induced cell death was tested. Similarly with estrogen (Est) , cortisone and cortisol but not aldosterone provided Taxol resistance in two kinds of RCC cell lines (Figure ?(Figure1a1a and Supplementary Figure S1B). Their inhibitory effect showed the dose-dependency (Figure ?(Figure1B).1B). Stress hormones can affect various kinds of tissues and cells [13, 24, 25], we next checked the effect of glucocorticoid hormones in lung and colon cancer cell lines and obtained the similar result that cortisol and cortisone inhibited Taxol-induced cell death as dose-dependent manner (Figure ?(Figure1C1C and Supplementary Figure S1C). In these cell lines, aldosterone did not alter the Taxol-sensitivity even in high dosage (Supplementary Figure S1C). Next, we checked the effect of cortisone and cortisol on other kinds of anti-cancer drugs. Similarly to Est , cortisol and cortisone did not alter the sensitivity to Adriamycin or etoposide (Figure ?(Figure1D1D and Supplementary Figure S1D). To know that cortisol/cortisone-induced Taxol resistance is achieved by ER- /Est signaling cascade , we treated an ER- inhibitor, Fulvestrant (FST), GSK2194069 and measured the Taxol-sensitivity. However, FST did not block the cortisone/cortisolinduced Taxol resistance (Figure ?(Figure1E),1E), indicate that these hormone’s effect on Taxol-induced cell death would be exerted by ER- independent PKX1 pathway. Open in a separate window Figure 1 Stress hormone induces Taxol resistanceA. Cortisone and Cortisol but not aldosterone block the Taxol-induced cell death. Aldosterone (5 M), cortisone (5 M), cortisol (5 M), and Taxol (3 Mm; Tax) were treated for 72 hr in VHL-positive C2V cells. Cell viability was measured by MTT assay. ** mean different group GSK2194069 by ANOVA test (p 0.001). B. Cortisone provides the Taxol resistance, like as Est. ACHN cells were treated with indicating dose of steroid hormones for 72 hr. Cell viability was determined by MTT assay. C. Cortisone and Cortisol but not aldosterone block the Taxol-induced cell death in non-RCC cell lines (Lung cance cell lines; A549, H1299, Colon cancer cell lines; HCT116, SW480). Aldosterone (5 M), cortisone (5 M), cortisol (5 M), and Taxol (3 M) were treated for 72 hr in VHL-positive C2V cells. Cell viability was measured by MTT assay. D. The specific effect of cortisone on Taxol-induced cell death. Differentially from Taxol (Tax), cortisone did not provide the resistance to DNA damage reagent such as Adriamycin (Adr) and Etoposide (Etop). Cells were incubated with indicated chemicals (Taxol 3 M; cortisone 5 M; Adr 2 g/ml; Etop 10 M) for 72 hr later. Cell viability was determined by MTT assay. E. Inhibition of ER- via Faslodex (FST) does not block GH-induced Taxol resistance. ACHN was incubated with FST (3 M), Taxol (3 M), cortisone (5 M) and cortisol (5 M) for 72 hr. Cell viability was measured by MTT assay. Stress hormone promote MTOC amplification Since elevated expression of -tubulin can overcome the Taxol-induced cell death [19, 26C30]. We first measured the -tubulin expression. As we expected, cortisol/cortisone obviously induced -tubulin in all of tested cell lines (Figure ?(Figure2A2A and Supplementary Figure S2A), and FST did not block the -tubulin induction (Figure ?(Figure2B).2B). In this experiment, we also observed the reduction of BRCA1 in response to cortisol and cortisone (Figure ?(Figure2B).2B). Indeed, reduction of BRCA1 has been observed in Est-mediated -tubulin induced condition [19, 31, 32]. However, in ER- negative cell lines, cortisone could induce -tubulin overexpression (Supplementary Figure S2B). In addition, they could promote MTOC amplification GSK2194069 (Supplementary Figure S2C). Indeed, cortisone-treatment could increase the average number of mitotic MTOC from 2 to 3 3 (Figure ?(Figure2C2C and ?and2D2D). Open in a separate window Figure 2 Stress hormone increases.