BACKGROUND: A radioprotective effect of low selenium doses on normal tissue and a possible radiosensitization of tumor cells at higher concentrations have been previously suggested. However, systematic experimental and clinical data are scarce. MATERIALS AND METHODS: C6 cells were cultured for 14 days at different selenite concentrations (0 microM, 2 microM, 3 microM and 3.6 microM) and irradiated with 0 Gy to 20 Gy. Plating efficiency and survival were determined using the colony assay. RESULTS: The overall radiosensitivity was low (D0,control=6.1 Gy). Irradiated cells exposed to increasing selenite concentrations showed a lower plating efficiency and, for doses > 2 Gy, a lower survival than the control. For Se concentrations of 0 microM, 2 microM and 3 microM, respectively, SF2 amounted to 0.72, 0.48 and 0.46, and SF5 to 0.37, 0.25 and 0.12. Student's t-test yielded a significant difference between the 0 microM and 3 microM curves at 5 Gy (p=0.02) and 10 Gy (p=0.009). CONCLUSION: Our experiments suggest a radiosensitizing effect of selenite in glioma cells at concentrations of 2-3 microM.
BACKGROUND: A radioprotective effect of low selenium doses on normal tissue and a possible radiosensitization of tumor cells at higher concentrations have been previously suggested. However, systematic experimental and clinical data are scarce. MATERIALS AND METHODS: C6 cells were cultured for 14 days at different selenite concentrations (0 microM, 2 microM, 3 microM and 3.6 microM) and irradiated with 0 Gy to 20 Gy. Plating efficiency and survival were determined using the colony assay. RESULTS: The overall radiosensitivity was low (D0,control=6.1 Gy). Irradiated cells exposed to increasing selenite concentrations showed a lower plating efficiency and, for doses > 2 Gy, a lower survival than the control. For Se concentrations of 0 microM, 2 microM and 3 microM, respectively, SF2 amounted to 0.72, 0.48 and 0.46, and SF5 to 0.37, 0.25 and 0.12. Student's t-test yielded a significant difference between the 0 microM and 3 microM curves at 5 Gy (p=0.02) and 10 Gy (p=0.009). CONCLUSION: Our experiments suggest a radiosensitizing effect of selenite in glioma cells at concentrations of 2-3 microM.
Authors: Marco Calvaruso; Gaia Pucci; Rosa Musso; Valentina Bravatà; Francesco P Cammarata; Giorgio Russo; Giusi I Forte; Luigi Minafra Journal: Int J Mol Sci Date: 2019-10-23 Impact factor: 5.923
Authors: Jossana A Damasco; Tymish Y Ohulchanskyy; Supriya Mahajan; Guanying Chen; Ajay Singh; Hilliard L Kutscher; Haoyuan Huang; Steven G Turowski; Joseph A Spernyak; Anurag K Singh; Jonathan F Lovell; Mukund Seshadri; Paras N Prasad Journal: Cancer Nanotechnol Date: 2021-02-05