TY - JOUR
T1 - Radiosensitization by hyperthermia: The effects of temperature, sequence, and time interval in cervical cell lines
AU - Mei, Xionge
AU - Cate, Rosemarie Ten
AU - van Leeuwen, Caspar M.
AU - Rodermond, Hans M.
AU - de Leeuw, Lidewij
AU - Dimitrakopoulou, Dionysia
AU - Stalpers, Lukas J. A.
AU - Crezee, Johannes
AU - Kok, H. Petra
AU - Franken, Nicolaas A. P.
AU - Oei, Arlene L.
PY - 2020/3
Y1 - 2020/3
N2 - Cervical cancers are almost exclusively caused by an infection with the human papillomavirus (HPV). When patients suffering from cervical cancer have contraindications for chemoradiotherapy, radiotherapy combined with hyperthermia is a good treatment option. Radiation-induced DNA breaks can be repaired by nonhomologous end-joining (NHEJ) or homologous recombination (HR). Hyperthermia can temporarily inactivate homologous recombination. Therefore, combining radiotherapy with hyperthermia can result in the persistence of more fatal radiation-induced DNA breaks. However, there is no consensus on the optimal sequence of radiotherapy and hyperthermia and the optimal time interval between these modalities. Moreover, the temperature of hyperthermia and HPV-type may also be important in radiosensitization by hyperthermia. In this study we thoroughly investigated the impact of different temperatures (37–42 °C), and the sequence of and time interval (0 up to 4 h) between ionizing radiation and hyperthermia on HPV16+: SiHa, Caski; HPV18+: HeLa, C4I; and HPV−: C33A, HT3 cervical cancer cell lines. Our results demonstrate that a short time interval between treatments caused more unrepaired DNA damages and more cell kill, especially at higher temperatures. Although hyperthermia before ionizing radiation may result in slightly more DNA damage, the sequence between hyperthermia and ionizing radiation yielded similar effects on cell survival.
AB - Cervical cancers are almost exclusively caused by an infection with the human papillomavirus (HPV). When patients suffering from cervical cancer have contraindications for chemoradiotherapy, radiotherapy combined with hyperthermia is a good treatment option. Radiation-induced DNA breaks can be repaired by nonhomologous end-joining (NHEJ) or homologous recombination (HR). Hyperthermia can temporarily inactivate homologous recombination. Therefore, combining radiotherapy with hyperthermia can result in the persistence of more fatal radiation-induced DNA breaks. However, there is no consensus on the optimal sequence of radiotherapy and hyperthermia and the optimal time interval between these modalities. Moreover, the temperature of hyperthermia and HPV-type may also be important in radiosensitization by hyperthermia. In this study we thoroughly investigated the impact of different temperatures (37–42 °C), and the sequence of and time interval (0 up to 4 h) between ionizing radiation and hyperthermia on HPV16+: SiHa, Caski; HPV18+: HeLa, C4I; and HPV−: C33A, HT3 cervical cancer cell lines. Our results demonstrate that a short time interval between treatments caused more unrepaired DNA damages and more cell kill, especially at higher temperatures. Although hyperthermia before ionizing radiation may result in slightly more DNA damage, the sequence between hyperthermia and ionizing radiation yielded similar effects on cell survival.
KW - Human papillomavirus
KW - Hyperthermia
KW - Ionizing radiation
KW - Sequence
KW - Time interval
UR - http://www.scopus.com/inward/record.url?scp=85081002194&partnerID=8YFLogxK
U2 - https://doi.org/10.3390/cancers12030582
DO - https://doi.org/10.3390/cancers12030582
M3 - Article
C2 - 32138173
SN - 2072-6694
VL - 12
JO - Cancers
JF - Cancers
IS - 3
M1 - 582
ER -