PMID- 32512849 OWN - NLM STAT- MEDLINE DCOM- 20210219 LR - 20211204 IS - 1422-0067 (Electronic) IS - 1422-0067 (Linking) VI - 21 IP - 11 DP - 2020 Jun 4 TI - Chronic Sulforaphane Administration Inhibits Resistance to the mTOR-Inhibitor Everolimus in Bladder Cancer Cells. LID - 10.3390/ijms21114026 [doi] LID - 4026 AB - Progressive bladder cancer growth is associated with abnormal activation of the mammalian target of the rapamycin (mTOR) pathway, but treatment with an mTOR inhibitor has not been as effective as expected. Rather, resistance develops under chronic drug use, prompting many patients to lower their relapse risk by turning to natural, plant-derived products. The present study was designed to evaluate whether the natural compound, sulforaphane (SFN), combined with the mTOR inhibitor everolimus, could block the growth and proliferation of bladder cancer cells in the short- and long-term. The bladder cancer cell lines RT112, UMUC3, and TCCSUP were exposed short- (24 h) or long-term (8 weeks) to everolimus (0.5 nM) or SFN (2.5 microM) alone or in combination. Cell growth, proliferation, apoptosis, cell cycle progression, and cell cycle regulating proteins were evaluated. siRNA blockade was used to investigate the functional impact of the proteins. Short-term application of SFN and/or everolimus resulted in significant tumor growth suppression, with additive inhibition on clonogenic tumor growth. Long-term everolimus treatment resulted in resistance development characterized by continued growth, and was associated with elevated Akt-mTOR signaling and cyclin-dependent kinase (CDK)1 phosphorylation and down-regulation of p19 and p27. In contrast, SFN alone or SFN+everolimus reduced cell growth and proliferation. Akt and Rictor signaling remained low, and p19 and p27 expressions were high under combined drug treatment. Long-term exposure to SFN+everolimus also induced acetylation of the H3 and H4 histones. Phosphorylation of CDK1 was diminished, whereby down-regulation of CDK1 and its binding partner, Cyclin B, inhibited tumor growth. In conclusion, the addition of SFN to the long-term everolimus application inhibits resistance development in bladder cancer cells in vitro. Therefore, sulforaphane may hold potential for treating bladder carcinoma in patients with resistance to an mTOR inhibitor. FAU - Justin, Saira AU - Justin S AD - Department of Urology, Goethe-University, 60590 Frankfurt am Main, Germany. FAU - Rutz, Jochen AU - Rutz J AD - Department of Urology, Goethe-University, 60590 Frankfurt am Main, Germany. FAU - Maxeiner, Sebastian AU - Maxeiner S AD - Department of Urology, Goethe-University, 60590 Frankfurt am Main, Germany. FAU - Chun, Felix K-H AU - Chun FK AD - Department of Urology, Goethe-University, 60590 Frankfurt am Main, Germany. FAU - Juengel, Eva AU - Juengel E AD - Department of Urology, Goethe-University, 60590 Frankfurt am Main, Germany. AD - Department of Urology and Pediatric Urology, University Medical Center Mainz, 55131 Mainz, Germany. FAU - Blaheta, Roman A AU - Blaheta RA AD - Department of Urology, Goethe-University, 60590 Frankfurt am Main, Germany. LA - eng GR - N/A/Brigitta & Norbert Muth Stiftung, Wiesbaden, Germany/ GR - N/A/Faculty Development Program Abroad 2014/2015 of the National University of Sciences & Technology (NUST), Pakistan/ PT - Journal Article DEP - 20200604 PL - Switzerland TA - Int J Mol Sci JT - International journal of molecular sciences JID - 101092791 RN - 0 (Anticarcinogenic Agents) RN - 0 (Isothiocyanates) RN - 0 (Protein Kinase Inhibitors) RN - 0 (Sulfoxides) RN - 9HW64Q8G6G (Everolimus) RN - EC 2.7.1.1 (MTOR protein, human) RN - EC 2.7.11.1 (TOR Serine-Threonine Kinases) RN - GA49J4310U (sulforaphane) SB - IM MH - Anticarcinogenic Agents/pharmacology MH - Apoptosis/drug effects MH - Cell Cycle/drug effects MH - Cell Line, Tumor MH - Cell Proliferation/drug effects MH - Dose-Response Relationship, Drug MH - Drug Resistance, Neoplasm/*drug effects/genetics MH - Everolimus/*pharmacology MH - Humans MH - Isothiocyanates/*administration & dosage MH - Protein Kinase Inhibitors/*pharmacology MH - Sulfoxides MH - TOR Serine-Threonine Kinases/*antagonists & inhibitors MH - Urinary Bladder Neoplasms PMC - PMC7312500 OTO - NOTNLM OT - bladder cancer OT - drug resistance OT - everolimus OT - growth OT - mTOR OT - proliferation OT - sulforaphane COIS- The authors declare no conflict of interest. EDAT- 2020/06/10 06:00 MHDA- 2021/02/20 06:00 PMCR- 2020/06/01 CRDT- 2020/06/10 06:00 PHST- 2020/04/28 00:00 [received] PHST- 2020/05/28 00:00 [revised] PHST- 2020/06/03 00:00 [accepted] PHST- 2020/06/10 06:00 [entrez] PHST- 2020/06/10 06:00 [pubmed] PHST- 2021/02/20 06:00 [medline] PHST- 2020/06/01 00:00 [pmc-release] AID - ijms21114026 [pii] AID - ijms-21-04026 [pii] AID - 10.3390/ijms21114026 [doi] PST - epublish SO - Int J Mol Sci. 2020 Jun 4;21(11):4026. doi: 10.3390/ijms21114026.