Hypericin-mediated photodynamic therapy of pituitary tumors: preclinical study in a GH4C1 rat tumor model


Objective Hypericin-mediated photodynamic therapy (PDT) is receiving greater interest as a potential treatment for a variety of tumors and nonmalignant disorders. PDT involves systemic administration of a photosensitizer that selectively accumulates within tumor tissue followed by focal light activation. In the presence of molecular oxygen, a photochemical reaction generates a reactive oxygen species that induces apoptosis in target cells. The purpose of this preclinical study was to evaluate the efficacy of hypericin-mediated PDT for treatment of pituitary adenoma in a rodent model. Methods Wistar-Furth rats were implanted with a pituitary adenoma rat cell line, GH4C1. Tumor masses were allowed to develop over 28 days; rats with tumors of comparable sizes were then assigned to three treatment groups: control (neither hypericin nor light); light only; and hypericin and light. Hypericin was administered in four doses (1 mg/kg) at 28-h intervals prior to light exposure, wherein those rats treated with light were exposed to a light source four hours after the last hypericin dose. Tumor size was measured up to 12 days after treatment. Results Over the short interval examined, hypericin-mediated PDT was not effective against large tumors greater than 1 cm3, but this treatment significantly slowed tumor growth for tumors less than 1 cm3. Histological evaluation and TUNEL assay of the treated tumor identified apoptotic clusters on the periphery of the PDT-treated specimens. Conclusions Hypericin-mediated PDT shows promise in its effectiveness in the treatment of residual small tumor rests.

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  1. 1.

    Dougherty TJ, Gomer CJ, Henderson BW, Jori G, Kessel D, Korbelik M, Moan J, Peng Q (1998) Photodynamic therapy. J Natl Cancer Inst 90:889–905

    PubMed  Article  CAS  Google Scholar 

  2. 2.

    Delaey E, Vandenbogaerde A, Merlevede W, de Witte P (2000) Photocytotoxicity of hypericin in normoxic and hypoxic conditions. J Photochem Photobiol B 56:19–24

    PubMed  Article  CAS  Google Scholar 

  3. 3.

    Piette J, Volanti C, Vantieghem A, Matroule JY, Habraken Y, Agostinis P (2003) Cell death and growth arrest in response to photodynamic therapy with membrane-bound photosensitizers. Biochem Pharmacol 66:1651–1659

    PubMed  Article  CAS  Google Scholar 

  4. 4.

    Agostinis P, Assefa Z, Vantieghem A, Vandenheede JR, Merlevede W, De Witte P (2000) Apoptotic and anti-apoptotic signaling pathways induced by photodynamic therapy with hypericin. Adv Enzyme Regul 40:157–182

    PubMed  Article  CAS  Google Scholar 

  5. 5.

    Assefa Z, Vantieghem A, Declercq W, Vandenabeele P, Vandenheede JR, Merlevede W, de Witte P, Agostinis P (1999) The activation of the c-Jun N-terminal kinase and p38 mitogen-activated protein kinase signaling pathways protects HeLa cells from apoptosis following photodynamic therapy with hypericin. J Biol Chem 274:8788–8796

    PubMed  Article  CAS  Google Scholar 

  6. 6.

    Hamilton HB, Hinton DR, Law RE, Gopalakrishna R, Su YZ, Chen ZH, Weiss MH, Couldwell WT (1996) Inhibition of cellular growth and induction of apoptosis in pituitary adenoma cell lines by the protein kinase C inhibitor hypericin: potential therapeutic application. J Neurosurg 85:329–334

    PubMed  CAS  Article  Google Scholar 

  7. 7.

    Fingar VH (1996) Vascular effects of photodynamic therapy. J Clin Laser Med Surg 14:323–328

    PubMed  CAS  Google Scholar 

  8. 8.

    Fingar VH, Taber SW, Haydon PS, Harrison LT, Kempf SJ, Wieman TJ (2000) Vascular damage after photodynamic therapy of solid tumors: a view and comparison of effect in pre-clinical and clinical models at the University of Louisville. In Vivo 14:93–100

    PubMed  CAS  Google Scholar 

  9. 9.

    Korbelik M (1996) Induction of tumor immunity by photodynamic therapy. J Clin Laser Med Surg 14:329–334

    PubMed  CAS  Google Scholar 

  10. 10.

    Korbelik M, Cecic I (1999) Contribution of myeloid and lymphoid host cells to the curative outcome of mouse sarcoma treatment by photodynamic therapy. Cancer Lett 137:91–98

    PubMed  Article  CAS  Google Scholar 

  11. 11.

    Korbelik M, Sun J, Payne PW (2003) Activation of poly(adenosine diphosphate-ribose) polymerase in mouse tumors treated by photodynamic therapy. Photochem Photobiol 78:400–406

    PubMed  Article  CAS  Google Scholar 

  12. 12.

    Chen B, Roskams T, Xu Y, Agostinis P, de Witte PA (2002) Photodynamic therapy with hypericin induces vascular damage and apoptosis in the RIF-1 mouse tumor model. Int J Cancer 98:284–290

    PubMed  Article  CAS  Google Scholar 

  13. 13.

    Vandenbogaerde AL, Kamuhabwa A, Delaey E, Himpens BE, Merlevede WJ, de Witte PA (1998) Photocytotoxic effect of pseudohypericin versus hypericin. J Photochem Photobiol B 45:87–94

    PubMed  Article  CAS  Google Scholar 

  14. 14.

    Agostinis P, Vantieghem A, Merlevede W, de Witte PA (2002) Hypericin in cancer treatment: more light on the way. Int J Biochem Cell Biol 34:221–241

    PubMed  Article  CAS  Google Scholar 

  15. 15.

    Chung PS, Rhee CK, Kim KH, Paek W, Chung J, Paiva MB, Eshraghi AA, Castro DJ, Saxton RE (2000) Intratumoral hypericin and KTP laser therapy for transplanted squamous cell carcinoma. Laryngoscope 110:1312–1316

    PubMed  Article  CAS  Google Scholar 

  16. 16.

    Chen B, de Witte PA (2000) Photodynamic therapy efficacy and tissue distribution of hypericin in a mouse P388 lymphoma tumor model. Cancer Lett 150:111–117

    PubMed  Article  CAS  Google Scholar 

  17. 17.

    Liu CD, Kwan D, Saxton RE, McFadden DW (2000) Hypericin and photodynamic therapy decreases human pancreatic cancer in vitro and in vivo. J Surg Res 93:137–143

    PubMed  Article  CAS  Google Scholar 

  18. 18.

    Pogue BW, O’Hara JA, Demidenko E, Wilmot CM, Goodwin IA, Chen B, Swartz HM, Hasan T (2003) Photodynamic therapy with verteporfin in the radiation-induced fibrosarcoma-1 tumor causes enhanced radiation sensitivity. Cancer Res 63:1025–1033

    PubMed  CAS  Google Scholar 

  19. 19.

    Marks PV, Furneaux C, Shivvakumar R (1992) An in vitro study of the effect of photodynamic therapy on human meningiomas. Br J Neurosurg 6:327–332

    PubMed  Article  CAS  Google Scholar 

  20. 20.

    Halberg FE, Sheline GE (1987) Radiotherapy of pituitary tumors. Endocrinol Metab Clin North Am 16:667–684

    PubMed  CAS  Google Scholar 

  21. 21.

    Bieri S, Sklar C, Constine L, Bernier J (1997) [Late effects of radiotherapy on the neuroendocrine system]. Cancer Radiother 1:706–716

    PubMed  CAS  Google Scholar 

  22. 22.

    Marks PV (1995) Adjuvant therapy for pituitary adenomas: the possible role of photodynamic therapy. Ann R Coll Surg Engl 77:308–312

    PubMed  CAS  Google Scholar 

  23. 23.

    Hockel M, Schlenger K, Hockel S, Vaupel P (1999) Hypoxic cervical cancers with low apoptotic index are highly aggressive. Cancer Res 59:4525–4528

    PubMed  CAS  Google Scholar 

  24. 24.

    Thomas C, MacGill RS, Miller GC, Pardini RS (1992) Photoactivation of hypericin generates singlet oxygen in mitochondria and inhibits succinoxidase. Photochem Photobiol 55:47–53

    PubMed  Article  CAS  Google Scholar 

  25. 25.

    Ehrenberg B, Anderson JL, Foote CS (1998) Kinetics and yield of singlet oxygen photosensitized by hypericin in organic and biological media. Photochem Photobiol 68:135–140

    PubMed  CAS  Google Scholar 

  26. 26.

    Kessel D, Luo Y (1999) Photodynamic therapy: a mitochondrial inducer of apoptosis. Cell Death Differ 6:28–35

    PubMed  Article  CAS  Google Scholar 

  27. 27.

    Vantieghem A, Xu Y, Declercq W, Vandenabeele P, Denecker G, Vandenheede JR, Merlevede W, de Witte PA, Agostinis P (2001) Different pathways mediate cytochrome c release after photodynamic therapy with hypericin. Photochem Photobiol 74:133–142

    PubMed  Article  CAS  Google Scholar 

  28. 28.

    Lavie G, Mazur Y, Lavie D, Meruelo D (1995) The chemical and biological properties of hypericin-a compound with a broad spectrum of biological activities. Med Res Rev 15:111–119

    PubMed  Article  CAS  Google Scholar 

  29. 29.

    Thomas C, Pardini RS (1992) Oxygen dependence of hypericin-induced phototoxicity to EMT6 mouse mammary carcinoma cells. Photochem Photobiol 55:831–837

    PubMed  Article  CAS  Google Scholar 

  30. 30.

    Blank M, Mandel M, Hazan S, Keisari Y, Lavie G (2001) Anti-cancer activities of hypericin in the dark. Photochem Photobiol 74:120–125

    PubMed  Article  CAS  Google Scholar 

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The authors thank Kristin Kraus for her editorial guidance in preparing this paper and Carolyn Pedone for her direction and assistance with cell culture and tissue preparation.

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Correspondence to William T. Couldwell.

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Cole, C.D., Liu, J.K., Sheng, X. et al. Hypericin-mediated photodynamic therapy of pituitary tumors: preclinical study in a GH4C1 rat tumor model. J Neurooncol 87, 255–261 (2008). https://doi.org/10.1007/s11060-007-9514-0

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  • Hypericin
  • Photodynamic therapy
  • Pituitary tumor