Inhibitory effect of ergosterol on bladder carcinogenesis is due to androgen signaling inhibition by brassicasterol, a metabolite of ergosterol


We previously revealed that Choreito, a traditional Kampo medicine, strongly inhibits bladder carcinogenesis promotion. We have also shown that Polyporus sclerotium, which is one of the crude drugs in Choreito, has the strongest bladder carcinogenesis inhibitory effect and that the ergosterol contained in Polyporus sclerotium is the main active component. In this study, we analyzed the mechanism by which ergosterol inhibits bladder carcinogenesis. Rats were given an N-butyl-N-(4-hydroxybutyl) nitrosamine (BHBN) solution ad libitum, and then a promoter [saccharin sodium (SS), DL-tryptophan, or BHBN] was administered together with ergosterol or its metabolite, brassicasterol. The bladders were removed from rats, and the inhibitory effect on carcinogenesis promotion was evaluated by an agglutination assay with concanavalin A (Con A). Although the oral administration of ergosterol inhibited the promotion of bladder carcinogenesis with SS, the intraperitoneal administration of brassicasterol showed a stronger effect. The effect of brassicasterol on carcinogenesis promotion was observed regardless of the type of promoter. Administration of testosterone to castrated rats increased the number of cell aggregates caused by Con A. In contrast, intraperitoneal administration of brassicasterol to castrated rats treated with testosterone significantly decreased the number of cell aggregates, confirming the inhibition of bladder carcinogenesis promotion. The inhibitory effect of ergosterol on bladder carcinogenesis is due to brassicasterol, a metabolite of ergosterol. The action of brassicasterol via androgen signaling may play a role in the inhibitory effect on bladder carcinogenesis promotion.

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  1. 1.

    Torre LA, Bray F, Siegel RL, Ferlay J, Lortet-Tieulent J, Jemal A (2015) Global cancer statistics, 2012. CA Cancer J Clin 65:87–108

    Article  Google Scholar 

  2. 2.

    DeGeorge KC, Holt HR, Hodges SC (2017) Bladder cancer: diagnosis and treatment. Am Fam Phys 96:507–514

    Google Scholar 

  3. 3.

    Schlack K, Boegemann M, Steinestel J, Schrader AJ, Krabbe LM (2016) The safety and efficacy of gemcitabine for the treatment of bladder cancer. Expert Rev Anticancer Ther 16:255–271

    CAS  Article  Google Scholar 

  4. 4.

    Unda-Urzaiz M, Fernandez-Gomez JM, Cozar-Olmo JM, Juarez A, Palou J, Martinez-Pineiro L (2018) Update on the role of endovesical chemotherapy in nonmuscle-invasive bladder cancer. Actas Urol Esp 42:73–76

    CAS  Article  Google Scholar 

  5. 5.

    Guallar-Garrido S, Julian E (2020) Bacillus calmette-guerin (bcg) therapy for bladder cancer: an update. Immuno Ther 9:1–11

    Article  Google Scholar 

  6. 6.

    Morales A, Eidinger D, Bruce AW (1976) Intracavitary bacillus calmette-guerin in the treatment of superficial bladder tumors. J Urol 116:180–183

    CAS  Article  Google Scholar 

  7. 7.

    Leal J, Luengo-Fernandez R, Sullivan R, Witjes JA (2016) Economic burden of bladder cancer across the European Union. Eur Urol 69:438–447

    Article  Google Scholar 

  8. 8.

    Sugiyama K, Azuhata Y, Matsuura D, Kameda Y, Yokota M (1994) Antitumor-promoting effect of Kampo formulations on rat urinary bladder carcinogenesis in a short-term test with concanavalin. J Trad Med 11:148–155

    CAS  Google Scholar 

  9. 9.

    Sugiyama K, Azuhata Y, Matsuura D (1994) Antitumor promoting effect of components of Chorei-to on rat urinary bladder carcinogenesis in a short-term test with concanavalin. J Trad Med 11:214–219

    Google Scholar 

  10. 10.

    Yazawa Y, Yokota M, Sugiyama K (2000) Antitumor promoting effect of an active component of Polyporus, ergosterol and related compounds on rat urinary bladder carcinogenesis in a short-term test with concanavalin A. Biol Pharm Bull 23:1298–1302

    CAS  Article  Google Scholar 

  11. 11.

    Homma Y, Kakizoe T, Samma S, Oyasu R (1987) Inhibition of N-butyl-N-(4-hydroxybutyl)nitrosamine-induced rat urinary bladder carcinogenesis by alpha-difluoromethylornithine. Cancer Res 47:6176–6179

    CAS  PubMed  Google Scholar 

  12. 12.

    Kakizoe T, Kawachi T, Okada M (1978) Concanavalin A agglutination of bladder cells of rats treated with bladder carcinogens; a rapid new test to detect bladder carcinogens A. Cancer Lett 5:285–290

    CAS  Article  Google Scholar 

  13. 13.

    Kakizoe T, Hasegawa F, Kawachi T, Sugimura T (1977) Isolation of transitional epithelial cells from the rat urinary bladder. Invest Urol 15:242–244

    CAS  PubMed  Google Scholar 

  14. 14.

    Kakizoe T, Komatsu H, Niijima T, Kawachi T, Sugimura T (1980) Increased agglutinability of bladder cells by concanavalin A after administration of carcinogens. Cancer Res 40:2006–2009

    CAS  PubMed  Google Scholar 

  15. 15.

    Ohtsubo T, Kageyama R, Koseki Y, Hagi J, Kotani A, Yamamoto K, Kusu F, Miura T, Hakamata H (2016) Determination of serum brassicasterol in spontaneously hypertensive rats stroke-prone fed a high-ergosterol diet by ultra performance liquid chromatography. Eur J Lipid Sci Technol 118:1074–1083

    CAS  Article  Google Scholar 

  16. 16.

    Tsugawa N, Okano T, Takeuchi A, Kayama M, Kobayashi T (1992) Metabolism of orally administered ergosterol and 7-dehydrocholesterol in rats and lack of evidence for their vitamin D biological activity. J Nutr Sci Vitaminol (Tokyo) 38:15–25

    CAS  Article  Google Scholar 

  17. 17.

    Cohen SM, Arai M, Jacobs JB, Friedell GH (1979) Promoting effect of saccharin and dl-tryptophan in urinary bladder carcinogenesis. Cancer Res 39:1207–1217

    CAS  PubMed  Google Scholar 

  18. 18.

    Cohen SM, Cano M, Earl RA, Carson SD, Garland EM (1991) A proposed role for silicates and protein in the proliferative effects of saccharin on the male rat urothelium. Carcinogenesis 12:1551–1555

    CAS  Article  Google Scholar 

  19. 19.

    Garland EM, St John M, Asamoto M, Eklund SH, Mattson BJ, Johnson LS, Cano M, Cohen SM (1994) A comparison of the effects of sodium saccharin in NBR rats and in intact and castrated male F344 rats. Cancer Lett 78:99–107

    CAS  Article  Google Scholar 

  20. 20.

    Dunning WF, Curtis MR, Maun ME (1950) The effect of added dietary tryptophane on the occurrence of 2-acetylaminofluorene-induced liver and bladder cancer in rats. Cancer Res 10:454–459

    CAS  PubMed  Google Scholar 

  21. 21.

    Hiraku Y, Inoue S, Oikawa S, Yamamoto K, Tada S, Nishino K, Kawanishi S (1995) Metal-mediated oxidative damage to cellular and isolated DNA by certain tryptophan metabolites. Carcinogenesis 16:349–356

    CAS  Article  Google Scholar 

  22. 22.

    Airoldi L, Magagnotti C, Bonfanti M, Chiappetta L, Lolli M, Medana C, De Gregorio G, Fanelli R (1994) Detection of O6-butyl- and O6-(4-hydroxybutyl)guanine in urothelial and hepatic DNA of rats given the bladder carcinogen N-nitrosobutyl(4-hydroxybutyl)amine. Carcinogenesis 15:2297–2301

    CAS  Article  Google Scholar 

  23. 23.

    Ito N, Hiasa Y, Tamai A, Okajima E, Kitamura H (1969) Histogenesis of urinary bladder tumors induced by N-butyl-N-(4-hydroxybutyl)nitrosamine in rats. Gan 60:401–410

    CAS  PubMed  Google Scholar 

  24. 24.

    Suzuki E, Okada M (1980) Metabolic fate of N-butyl-N-(4-hydroxybutyl) nitrosamine in the rat. Gan 71:856–862

    CAS  PubMed  Google Scholar 

  25. 25.

    Li Y, Izumi K, Miyamoto H (2012) The role of the androgen receptor in the development and progression of bladder cancer. Jpn J Clin Oncol 42:569–577

    Article  Google Scholar 

  26. 26.

    Bertram JS, Craig AW (1972) Specific induction of bladder cancer in mice by butyl-(4-hydroxybutyl)-nitrosamine and the effects of hormonal modifications on the sex difference in response. Eur J Cancer 8:587–594

    CAS  Article  Google Scholar 

  27. 27.

    Okajima E, Hiramatsu T, Iriya K, Ijuin M, Matsushima S (1975) Effects of sex hormones on development of urinary bladder tumours in rats induced by N-butyl-N-(4-hydroxybutyl) nitrosamine. Urol Res 3:73–79

    CAS  Article  Google Scholar 

  28. 28.

    Chang CS, Kokontis J, Liao ST (1988) Molecular cloning of human and rat complementary DNA encoding androgen receptors. Science 240:324–326

    CAS  Article  Google Scholar 

  29. 29.

    Imada S, Akaza H, Ami Y, Koiso K, Ideyama Y, Takenaka T (1997) Promoting effects and mechanisms of action of androgen in bladder carcinogenesis in male rats. Eur Urol 31:360–364

    CAS  Article  Google Scholar 

  30. 30.

    Miyamoto H, Yang Z, Chen YT, Ishiguro H, Uemura H, Kubota Y, Nagashima Y, Chang YJ, Hu YC, Tsai MY, Yeh S, Messing EM, Chang C (2007) Promotion of bladder cancer development and progression by androgen receptor signals. J Natl Cancer Inst 99:558–568

    CAS  Article  Google Scholar 

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Correspondence to Nobutomo Ikarashi or Kiyoshi Sugiyama.

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Yazawa, Y., Ikarashi, N., Hoshino, M. et al. Inhibitory effect of ergosterol on bladder carcinogenesis is due to androgen signaling inhibition by brassicasterol, a metabolite of ergosterol. J Nat Med (2020).

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  • Ergosterol
  • Brassicasterol
  • Bladder carcinogenesis
  • Androgen signal