Cancer Chemotherapy and Pharmacology

, Volume 83, Issue 1, pp 43–52 | Cite as

Clinical and in vitro studies of the correlation between MGMT and the effect of streptozocin in pancreatic NET

  • Susumu HijiokaEmail author
  • Keiichiro Sakuma
  • Masahiro Aoki
  • Nobumasa Mizuno
  • Takamichi Kuwahara
  • Nozomi Okuno
  • Kazuo Hara
  • Yasushi Yatabe
Original Article



This study aimed to determine the correlation between DNA repair enzyme O6-methylguanine DNA methyltransferase (MGMT) status and the response to streptozocin in advanced well-differentiated pancreatic neuroendocrine tumors (WD panNETs).


To test the hypothesis that MGMT deficiency was required for an alkylating drug response, we retrospectively reviewed the response of 13 patients with WD panNETs to alkylating agents in relation to MGMT status. We also studied MGMT expression in streptozocin resistance using panNET cell lines.


The cohort included 54% of patients with and 46% without MGMT expression. Among these, 83.3% (5/6) of MGMT-negative cases showed a partial response to streptozocin. In contrast, only 14.2% (1/7) of MGMT-positive cases showed a partial response (P = 0.013). Induced expression of MGMT in BON1 cells (a panNET cell line with undetectable endogenous MGMT) produced streptozocin resistance. Knockdown of MGMT in QGP1 cells, which express MGMT endogenously, did not alter the response to streptozocin.


We observed a relationship between MGMT status and streptozocin response in both patients and cell culture. Despite limited cases examined, high concordance of negative expression of MGMT and response to streptozocin treatment suggest that MGMT expression can be a potential biomarker for this treatment.


MGMT Streptozocin Pancreatic neuroendocrine tumors Methylation BON1 



The authors extend our sincere appreciation to Dr. Hironori Koga (Kurume University, Kurume, Japan).


This study was funded by the Aichi Cancer Research Foundation, Japan (K.S.).

Compliance with ethical standards

Conflict of interest

Susumu Hijioka has received speaker honoraria from Novelphama, Novartis, and Teijin Pharma. Nobumasa Mizuno has received research funding from AstraZeneca, Zeria Pharmaceutical, Taiho Pharmaceutical, Merck Serono, Eisai, NanoCarrier, MSD, Dainippon Sumitomo Pharma, and Novartis. Keiichiro Sakuma, Masahiro Aoki, Takamichi Kuwahara, Nozomi Okuno, Kazuo Hara, and Yasushi Yatabe have no conflicts of interest.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Informed consent

Informed consent was obtained from all individual participants included in the study.

Supplementary material

280_2018_3700_MOESM1_ESM.docx (23 kb)
Supplementary material 1 (DOCX 22 KB)
280_2018_3700_MOESM2_ESM.tif (66 kb)
Online Resource 1. OS for pancreatic neuroendocrine tumor patients treated with streptozocin therapy. The solid line is MGMT- negative (deficient) as determined by IHC, and the dotted line is MGMT- positive (intact) as determined by IHC. The median OS of the MGMT negative and MGMT positive groups was 827 days (range,163-1296), and 447 days (range, 81–1218 days), respectively (P = 0.339). (TIF 66 KB)
280_2018_3700_MOESM3_ESM.tif (167 kb)
Online Resource 2. MTT assay of MGMT-knockdown QGP1 cells treated with streptozocin. MTT activity was assayed in MGMT-knockdown QGP1 subclones treated with streptozocin. P = 0.022 (*) compared with Luc shRNA-transduced QGP1 cells treated with the same concentration of streptozocin. (TIF 167 KB)


  1. 1.
    Dasari A, Shen C, Halperin D, Zhao B, Zhou S, Xu Y, Shih T, Yao JC (2017) Trends in the incidence, prevalence, and survival outcomes in patients with neuroendocrine tumors in the United States. JAMA Oncol 3:1335–1342. CrossRefGoogle Scholar
  2. 2.
    Panzuto F, Boninsegna L, Fazio N, Campana D, Pia Brizzi M, Capurso G, Scarpa A, De Braud F, Dogliotti L, Tomassetti P, Delle Fave G, Falconi M (2011) Metastatic and locally advanced pancreatic endocrine carcinomas: analysis of factors associated with disease progression. J Clin Oncol 29:2372–2377. CrossRefGoogle Scholar
  3. 3.
    Caplin ME, Pavel M, Cwikla JB, Phan AT, Raderer M, Sedlackova E, Cadiot G, Wolin EM, Capdevila J, Wall L, Rindi G, Langley A, Martinez S, Blumberg J, Ruszniewski P (2014) Lanreotide in metastatic enteropancreatic neuroendocrine tumors. N Engl J Med 371:224–233. CrossRefGoogle Scholar
  4. 4.
    Yao JC, Shah MH, Ito T, Bohas CL, Wolin EM, Van Cutsem E, Hobday TJ, Okusaka T, Capdevila J, de Vries EG, Tomassetti P, Pavel ME, Hoosen S, Haas T, Lincy J, Lebwohl D, Oberg K (2011) Everolimus for advanced pancreatic neuroendocrine tumors. N Engl J Med 364:514–523. CrossRefGoogle Scholar
  5. 5.
    Raymond E, Dahan L, Raoul JL, Bang YJ, Borbath I, Lombard-Bohas C, Valle J, Metrakos P, Smith D, Vinik A, Chen JS, Horsch D, Hammel P, Wiedenmann B, Van Cutsem E, Patyna S, Lu DR, Blanckmeister C, Chao R, Ruszniewski P (2011) Sunitinib malate for the treatment of pancreatic neuroendocrine tumors. N Engl J Med 364:501–513. CrossRefGoogle Scholar
  6. 6.
    Rinke A, Muller HH, Schade-Brittinger C, Klose KJ, Barth P, Wied M, Mayer C, Aminossadati B, Pape UF, Blaker M, Harder J, Arnold C, Gress T, Arnold R (2009) Placebo-controlled, double-blind, prospective, randomized study on the effect of octreotide LAR in the control of tumor growth in patients with metastatic neuroendocrine midgut tumors: a report from the PROMID Study Group. J Clin Oncol 27:4656–4663. CrossRefGoogle Scholar
  7. 7.
    Pavel M, Baudin E, Couvelard A, Krenning E, Oberg K, Steinmuller T, Anlauf M, Wiedenmann B, Salazar R (2012) ENETS Consensus Guidelines for the management of patients with liver and other distant metastases from neuroendocrine neoplasms of foregut, midgut, hindgut, and unknown primary. Neuroendocrinology 95:157–176. CrossRefGoogle Scholar
  8. 8.
    Ito T, Hijioka S, Masui T, Kasajima A, Nakamoto Y, Kobayashi N, Komoto I, Hijioka M, Lee L, Igarashi H, Jensen RT, Imamura M (2017) Advances in the diagnosis and treatment of pancreatic neuroendocrine neoplasms in Japan. J Gastroenterol 52:9–18. CrossRefGoogle Scholar
  9. 9.
    Clewemar Antonodimitrakis P, Sundin A, Wassberg C, Granberg D, Skogseid B, Eriksson B (2016) Streptozocin and 5-fluorouracil for the treatment of pancreatic neuroendocrine tumors: efficacy, prognostic factors and toxicity. Neuroendocrinology 103:345–353. CrossRefGoogle Scholar
  10. 10.
    Krug S, Boch M, Daniel H, Nimphius W, Muller D, Michl P, Rinke A, Gress TM (2015) Streptozocin-based chemotherapy in patients with advanced neuroendocrine neoplasms–predictive and prognostic markers for treatment stratification. PLoS One 10:e0143822. CrossRefGoogle Scholar
  11. 11.
    Dilz LM, Denecke T, Steffen IG, Prasad V, von Weikersthal LF, Pape UF, Wiedenmann B, Pavel M (2015) Streptozocin/5-fluorouracil chemotherapy is associated with durable response in patients with advanced pancreatic neuroendocrine tumours. Eur J Cancer (Oxf) 51:1253–1262. CrossRefGoogle Scholar
  12. 12.
    Aoki T, Kokudo N, Komoto I, Takaori K, Kimura W, Sano K, Takamoto T, Hashimoto T, Okusaka T, Morizane C, Ito T, Imamura M (2015) Streptozocin chemotherapy for advanced/metastatic well-differentiated neuroendocrine tumors: an analysis of a multi-center survey in Japan. J Gastroenterol 50:769–775. CrossRefGoogle Scholar
  13. 13.
    Strosberg JR, Fine RL, Choi J, Nasir A, Coppola D, Chen DT, Helm J, Kvols L (2011) First-line chemotherapy with capecitabine and temozolomide in patients with metastatic pancreatic endocrine carcinomas. Cancer 117:268–275. CrossRefGoogle Scholar
  14. 14.
    Liu L, Gerson SL (2006) Targeted modulation of MGMT: clinical implications. Clin Cancer Res 12:328–331. CrossRefGoogle Scholar
  15. 15.
    Zhang J, Stevens MF, Bradshaw TD (2012) Temozolomide: mechanisms of action, repair and resistance. Curr Mol Pharmacol 5:102–114CrossRefGoogle Scholar
  16. 16.
    Christmann M, Verbeek B, Roos WP, Kaina B (2011) O(6)-Methylguanine-DNA methyltransferase (MGMT) in normal tissues and tumors: enzyme activity, promoter methylation and immunohistochemistry. Biochim Biophys Acta 1816:179–190. Google Scholar
  17. 17.
    Esteller M, Hamilton SR, Burger PC, Baylin SB, Herman JG (1999) Inactivation of the DNA repair gene O6-methylguanine-DNA methyltransferase by promoter hypermethylation is a common event in primary human neoplasia. Cancer Res 59:793–797Google Scholar
  18. 18.
    Hegi ME, Diserens AC, Gorlia T, Hamou MF, de Tribolet N, Weller M, Kros JM, Hainfellner JA, Mason W, Mariani L, Bromberg JE, Hau P, Mirimanoff RO, Cairncross JG, Janzer RC, Stupp R (2005) MGMT gene silencing and benefit from temozolomide in glioblastoma. N Engl J Med 352:997–1003. CrossRefGoogle Scholar
  19. 19.
    Weller M, Stupp R, Reifenberger G, Brandes AA, van den Bent MJ, Wick W, Hegi ME (2010) MGMT promoter methylation in malignant gliomas: ready for personalized medicine? Nat Rev Neurol 6:39–51. CrossRefGoogle Scholar
  20. 20.
    Gorlia T, van den Bent MJ, Hegi ME, Mirimanoff RO, Weller M, Cairncross JG, Eisenhauer E, Belanger K, Brandes AA, Allgeier A, Lacombe D, Stupp R (2008) Nomograms for predicting survival of patients with newly diagnosed glioblastoma: prognostic factor analysis of EORTC and NCIC trial 26981-22981/CE.3. Lancet Oncol 9:29–38. CrossRefGoogle Scholar
  21. 21.
    Karayan-Tapon L, Quillien V, Guilhot J, Wager M, Fromont G, Saikali S, Etcheverry A, Hamlat A, Loussouarn D, Campion L, Campone M, Vallette FM, Gratas-Rabbia-Re C (2010) Prognostic value of O6-methylguanine-DNA methyltransferase status in glioblastoma patients, assessed by five different methods. J Neurooncol 97:311–322. CrossRefGoogle Scholar
  22. 22.
    Raj N, Klimstra DS, Horvat N, Zhang L, Chou JF, Capanu M, Basturk O, Do RKG, Allen PJ, Reidy-Lagunes D (2017) O6-Methylguanine DNA methyltransferase status does not predict response or resistance to alkylating agents in well-differentiated pancreatic neuroendocrine tumors. Pancreas 46:758–763. CrossRefGoogle Scholar
  23. 23.
    Girot P, Dumars C, Mosnier JF, Muzellec L, Senellart H, Foubert F, Caroli-Bosc FX, Cauchin E, Regenet N, Matysiak-Budnik T, Touchefeu Y (2017) Short article: Evaluation of O6-methylguanine-DNA methyltransferase as a predicting factor of response to temozolomide-based chemotherapy in well-differentiated metastatic pancreatic neuroendocrine tumors. Eur J Gastroenterol Hepatol 29:826–830. CrossRefGoogle Scholar
  24. 24.
    Cives M, Ghayouri M, Morse B, Brelsford M, Black M, Rizzo A, Meeker A, Strosberg J (2016) Analysis of potential response predictors to capecitabine/temozolomide in metastatic pancreatic neuroendocrine tumors. Endocr Relat Cancer 23:759–767. CrossRefGoogle Scholar
  25. 25.
    Walter T, van Brakel B, Vercherat C, Hervieu V, Forestier J, Chayvialle JA, Molin Y, Lombard-Bohas C, Joly MO, Scoazec JY (2015) O6-Methylguanine-DNA methyltransferase status in neuroendocrine tumours: prognostic relevance and association with response to alkylating agents. Br J Cancer 112:523–531. CrossRefGoogle Scholar
  26. 26.
    Schmitt AM, Pavel M, Rudolph T, Dawson H, Blank A, Komminoth P, Vassella E, Perren A (2014) Prognostic and predictive roles of MGMT protein expression and promoter methylation in sporadic pancreatic neuroendocrine neoplasms. Neuroendocrinology 100:35–44. CrossRefGoogle Scholar
  27. 27.
    Kulke MH, Hornick JL, Frauenhoffer C, Hooshmand S, Ryan DP, Enzinger PC, Meyerhardt JA, Clark JW, Stuart K, Fuchs CS, Redston MS (2009) O6-methylguanine DNA methyltransferase deficiency and response to temozolomide-based therapy in patients with neuroendocrine tumors. Clin Cancer Res 15:338–345. CrossRefGoogle Scholar
  28. 28.
    Ekeblad S, Sundin A, Janson ET, Welin S, Granberg D, Kindmark H, Dunder K, Kozlovacki G, Orlefors H, Sigurd M, Oberg K, Eriksson B, Skogseid B (2007) Temozolomide as monotherapy is effective in treatment of advanced malignant neuroendocrine tumors. Clin Cancer Res 13:2986–2991. CrossRefGoogle Scholar
  29. 29.
    Cros J, Hentic O, Rebours V, Zappa M, Gille N, Theou-Anton N, Vernerey D, Maire F, Levy P, Bedossa P, Paradis V, Hammel P, Ruszniewski P, Couvelard A (2016) MGMT expression predicts response to temozolomide in pancreatic neuroendocrine tumors. Endocr Relat Cancer 23:625–633. CrossRefGoogle Scholar
  30. 30.
    Owen DH, Alexander AJ, Konda B, Wei L, Hemminger JA, Schmidt CR, Abdel-Misih SRZ, Dillhoff ME, Sipos JA, Kirschner LS, Shah MH (2017) Combination therapy with capecitabine and temozolomide in patients with low and high grade neuroendocrine tumors, with an exploratory analysis of O(6)-methylguanine DNA methyltransferase as a biomarker for response. Oncotarget 8:104046–104056. Google Scholar
  31. 31.
    Campana D, Walter T, Pusceddu S, Gelsomino F, Graillot E, Prinzi N, Spallanzani A, Fiorentino M, Barritault M, Dall’Olio F, Brighi N, Biasco G (2018) Correlation between MGMT promoter methylation and response to temozolomide-based therapy in neuroendocrine neoplasms: an observational retrospective multicenter study. Endocrine 60:490–498. CrossRefGoogle Scholar
  32. 32.
    Townsend CM Jr, Ishizuka J, Thompson JC (1993) Studies of growth regulation in a neuroendocrine cell line. Acta Oncol (Stockh) 32:125–130CrossRefGoogle Scholar
  33. 33.
    Fine RL, Gulati AP, Krantz BA, Moss RA, Schreibman S, Tsushima DA, Mowatt KB, Dinnen RD, Mao Y, Stevens PD, Schrope B, Allendorf J, Lee JA, Sherman WH, Chabot JA (2013) Capecitabine and temozolomide (CAPTEM) for metastatic, well-differentiated neuroendocrine cancers: the Pancreas Center at Columbia University experience. Cancer Chemother Pharmacol 71:663–670. CrossRefGoogle Scholar
  34. 34.
    Krug S, Boch M, Nimphius W, Gress TM, Michl P, Rinke A (2017) Relevance of dihydropyrimidine-dehydrogenase and thymidylate-synthase in patients with pancreatic neuroendocrine neoplasms treated with 5-FU-based chemotherapy. Pancreatology 17:139–145. CrossRefGoogle Scholar
  35. 35.
    Maxwell JA, Johnson SP, Quinn JA, McLendon RE, Ali-Osman F, Friedman AH, Herndon JE IInd, Bierau K, Bigley J, Bigner DD, Friedman HS (2006) Quantitative analysis of O6-alkylguanine-DNA alkyltransferase in malignant glioma. Mol Cancer Ther 5:2531–2539. CrossRefGoogle Scholar
  36. 36.
    Preusser M, Charles Janzer R, Felsberg J, Reifenberger G, Hamou MF, Diserens AC, Stupp R, Gorlia T, Marosi C, Heinzl H, Hainfellner JA, Hegi M (2008) Anti-O6-methylguanine-methyltransferase (MGMT) immunohistochemistry in glioblastoma multiforme: observer variability and lack of association with patient survival impede its use as clinical biomarker. Brain Pathol (Zurich) 18:520–532. Google Scholar
  37. 37.
    Mollemann M, Wolter M, Felsberg J, Collins VP, Reifenberger G (2005) Frequent promoter hypermethylation and low expression of the MGMT gene in oligodendroglial tumors. Int J Cancer 113:379–385. CrossRefGoogle Scholar
  38. 38.
    Sato K, Kitajima Y, Kohya N, Miyoshi A, Koga Y, Miyazaki K (2005) Deficient MGMT and proficient hMLH1 expression renders gallbladder carcinoma cells sensitive to alkylating agents through G2-M cell cycle arrest. Int J Oncol 26:1653–1661Google Scholar
  39. 39.
    Sato K, Kitajima Y, Nakagawachi T, Soejima H, Miyoshi A, Koga Y, Miyazaki K (2005) Cisplatin represses transcriptional activity from the minimal promoter of the O6-methylguanine methyltransferase gene and increases sensitivity of human gallbladder cancer cells to 1-(4-amino-2-methyl-5-pyrimidinyl) methyl-3-2-chloroethyl)-3-nitrosourea. Oncol Rep 13:899–906Google Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of GastroenterologyAichi Cancer Center HospitalNagoyaJapan
  2. 2.Department of Hepatobiliary and Pancreatic OncologyNational Cancer Center HospitalTokyoJapan
  3. 3.Division of PathophysiologyAichi Cancer Center Research InstituteNagoyaJapan
  4. 4.Department of Cancer Genetics, Program in Function Construction MedicineNagoya University Graduate School of MedicineNagoyaJapan
  5. 5.Department of Pathology and Molecular DiagnosticsAichi Cancer Center HospitalNagoyaJapan

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