Cellular and molecular portrait of eleven human glioblastoma cell lines under photon and carbon ion irradiation

• This study provides consistent database of the cellular and molecular response of glioblastoma cells to photon irradiation.
• To the best of our knowledge it represents the largest archive for carbon ion hadrontherapy response of glioblastoma cells.
• This type of archive is intended to customize the treatment of patients. It will allow the development of new predictive mathematical models for the response of tumors to radiation.
• The database realized could ultimately improve hadrontherapy treatment plans.

This study aimed to examine the cellular and molecular long-term responses of glioblastomas to radiotherapy and hadrontherapy in order to better understand the biological effects of carbon beams in cancer treatment.Eleven human glioblastoma cell lines, displaying gradual radiosensitivity, were irradiated with photons or carbon ions. Independently of p53 or O6-methylguanine-DNA methyltransferase1 status, all cell lines responded to irradiation by a G2/M phase arrest followed by the appearance of mitotic catastrophe, which was concluded by a ceramide-dependent-apoptotic cell death. Statistical analysis demonstrated that: (i) the SF22 and the D103 values for photon are correlated with that obtained in response to carbon ions; (ii) regardless of the p53, MGMT status, and radiosensitivity, the release of ceramide is associated with the induction of late apoptosis; and (iii) the appearance of polyploid cells after photon irradiation could predict the Relative Biological Efficiency4 to carbon ions.This large collection of data should increase our knowledge in glioblastoma radiobiology in order to better understand, and to later individualize, appropriate radiotherapy treatment for patients who are good candidates.