In vitro studies of DNA damage and repair mechanisms induced by BNCT in a poorly differentiated thyroid carcinoma cell line
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Boron neutron capture therapy (BNCT) for aggressive tumors is based on nuclear reaction [10B (n, α) 7Li]. Previously, we demonstrated that BNCT could be applied for the treatment of undifferentiated thyroid carcinoma. The aim of the present study was to describe the DNA damage pattern and the repair pathways that are activated by BNCT in thyroid cells. We analyzed γH2AX foci and the expression of Ku70, Rad51 and Rad54, main effector enzymes of non-homologous end joining (NHEJ) and homologous recombination repair (HRR) pathways, respectively, in thyroid follicular carcinoma cells. The studied groups were: (1) C [no irradiation], (2) gamma [60Co source], (3) N [neutron beam alone], (4) BNCT [neutron beam plus 10 µg 10B/ml of boronphenylalanine (10BPA)]. The total absorbed dose was always 3 Gy. The results showed that the number of nuclear γH2AX foci was higher in the gamma group than in the N and BNCT groups (30 min–24 h) (p < 0.001). However, the focus size was significantly larger in BNCT compared to other groups (p < 0.01). The analysis of repair enzymes showed a significant increase in Rad51 and Rad54 mRNA at 4 and 6 h, respectively; in both N and BNCT groups and the expression of Ku70 did not show significant differences between groups. These findings are consistent with an activation of HRR mechanism in thyroid cells. A melanoma cell line showed different DNA damage pattern and activation of both repair pathways. These results will allow us to evaluate different blocking points, to potentiate the damage induced by BNCT.
KeywordsDamage Repair Pathways BNCT Thyroid cancer
A part of these studies was supported by grants from the Scientific and Technical Research National Council (CONICET) and Secretary of Science and Technology (SEPCYT).
Compliance with ethical standards
Conflict of interest
We declare that there is no conflict of interest in this paper.
- Aiyama H, Nakai K, Yamamoto T, Nariai T, Kumada H, Ishikawa E, Isobe T, Endo K, Takada T, Yoshida F, Shibata Y, Matsumura A (2011) A clinical trial protocol for second line treatment of malignant brain tumors with BNCT at University of Tsukuba. Appl Radiat Isot 69(12):1819–1822CrossRefGoogle Scholar
- Antonelli F, Campa A, Esposito G, Giardullo P, Belli M, Dini V, Meschini S, Simone G, Sorrentino E, Gerardi S, Cirrone GA, Tabocchini MA. (2015). Induction and Repair of DNA DSB as Revealed by H2AX Phosphorylation Foci in Human Fibroblasts Exposed to Low- and High-LET radiation: relationship with early and delayed reproductive cell death. Radiat Res 183(4):417–431. https://doi.org/10.1667/RR13855.1
- Bracalente C, Ibañez I, Molinari B, Palmieri M, Kreiner A, Valda A, Davidson J, Durán H (2013). Induction and persistence of large γH2AX foci by high linear energy transfer radiation in DNA-dependent protein kinase-deficient cells. Int J Radiat Oncol Biol Phys 87(4):785–794Google Scholar
- Busse PM, Harling OK, Palmer MR, Kiger WS 3rd, Kaplan J, Kaplan I, Chuang CF, Goorley JT, Riley KJ, Newton TH, Santa Cruz GA, Lu XQ, Zamenhof RG (2003) A critical examination of the results from the Harvard-MIT NCT program phase I clinical trial of neutron capture therapy for intracranial disease. J Neurooncol 62(1–2):111–121Google Scholar
- Chiacchio S, Lorenzoni A, Boni G, Rubello D, Elisei R, Mariani G (2008) Anaplastic thyroid cancer: prevalence, diagnosis and treatment. Minerva Endocrinol 33(4):341–357Google Scholar
- Dagrosa MA, Crivello M, Perona M, Thorp S, Santa Cruz GA, Pozzi E, Casal M, Thomasz L, Cabrini R, Kahl S, Juvenal GJ, Pisarev MA (2011b) First evaluation of the biologic effectiveness factors of boron neutron capture therapy (BNCT) in a human colon carcinoma cell line. Int J Radiat Oncol Biol Phys 79(1):262–268CrossRefGoogle Scholar
- Ibañez I, Bracalante C, Molinari B, Palmieri M, Policastro L, Kreiner A, Burlon A, Valda A, Navalesi D, Davidson J, Davidson M, Vazquez M, Ozafrán M, Durán H (2009). Induction and rejoining of DNA double strand breaks assessed by H2AX phosphorylation in melanoma cells irradiated with proton and lithium beams. Int J Radiat Oncol Biol Phys, 74(4):1226–1235CrossRefGoogle Scholar
- Jen-Chung Ko Shih-CiCiou, Cheng C-M, Wang L-H, Hong J-H, Jheng M-Y, Ling S, Lin Y (2008) Involvement of Rad51 in cytotoxicity induced by epidermal growth factor receptor inhibitor (gefitinib, IressaR) and chemotherapeutic agents in human lung cancer cells. Carcinogenesis 29(7):1448–1458Google Scholar
- Joensuu H, Kankaanranta L, Tenhunen M, Saarilahti K (2011) Boron Neutron Capture Therapy (BNCT) as cancer treatment. Duodecim 127(16):1697–1703Google Scholar
- Korabiowska M, Quentin T, Schlott T, Bauer H, Kunze E (2004) Down-regulation of Ku 70 Ku 80 mRNA expression in transitional cell carcinomas of the urinary bladder related to tumor progression. World J Urol 2(6):431–440Google Scholar
- Matsuda M, Miyagawa K, Takahashi M, Fukuda T, Kataoka T, Asahara T, Inui H, Watatani M, Yasutomi M, Kamada N, Dohi K, Kamiya K (1999) Mutations in the RAD54 recombination gene in primary cancers. Oncogene 18:3427–3430Google Scholar
- Miller M, Quintana J, Ojeda J, Langan S, Thorp S, Pozzi E, Sztejnberg M, Estryk G, Nosal R, Saire E, Agrazar H, Graiño F (2009) New irradiation facility for biomedical applications at the RA-3 reactor thermal column. Appl Radiat Isot 67(7–8 Suppl):S226-9Google Scholar
- Perona M, Rodríguez C, Carpano M, Thomasz L, Nievas S, Olivera M, Thorp S, Curotto P, Pozzi E, Kahl S, Pisarev M, Juvenal G, Dagrosa A (2013). Improvement of the Boron Neutron Capture therapy (BNCT) by the previous administration of the histone deacetylase inhibitor sodium butyrate for the treatment of thyroid carcinoma. Radiat Environ Biophys. 52(3):363–373Google Scholar