TY - JOUR
T1 - Involvement of adenosine A2B receptor in radiation-induced translocation of epidermal growth factor receptor and DNA damage response leading to radioresistance in human lung cancer cells
AU - Kitabatake, Kazuki
AU - Yoshida, Eiko
AU - Kaji, Toshiyuki
AU - Tsukimoto, Mitsutoshi
N1 - Funding Information:
This work was supported in part by JSPS KAKENHI Grant number JP 19K08185 (Grant-in-Aid for Scientific Research (C)).
PY - 2020/1
Y1 - 2020/1
N2 - Background: Adenosine receptors are involved in tumor growth, progression, and response to therapy. Among them, A2B receptor is highly expressed in various tumors. Furthermore, ionizing radiation induces translocation of epidermal growth factor receptor (EGFR), which promotes DNA repair and contributes to radioresistance. We hypothesized that A2B receptor might be involved in the translocation of EGFR. Methods: We investigated whether A2B receptor is involved in EGFR translocation and DNA damage response (γH2AX/53BP1 focus formation) of lung cancer cells by means of immunofluorescence studies. Radiosensitivity was evaluated by colony formation assay after γ-irradiation. Results: A2B receptor was expressed at higher levels in cancer cells than in normal cells. A2B receptor antagonist treatment or A2B receptor knockdown suppressed EGFR translocation, γH2AX/53BP1 focus formation, and colony formation of lung cancer cell lines A549, calu-6 and NCI-H446, compared with a normal cell line (beas-2b). γ-Irradiation-induced phosphorylation of src and EGFR was also attenuated by suppression of A2B receptor expression. Conclusion: Activation of A2B receptor mediates γ-radiation-induced translocation of EGFR and phosphorylation of src and EGFR, thereby promoting recovery of irradiated lung cancer cells from DNA damage. General significance: Our results indicate that A2B receptors contribute to radiation resistance in a cancer-cell-specific manner, and may be a promising target for radiosensitizers in cancer radiotherapy.
AB - Background: Adenosine receptors are involved in tumor growth, progression, and response to therapy. Among them, A2B receptor is highly expressed in various tumors. Furthermore, ionizing radiation induces translocation of epidermal growth factor receptor (EGFR), which promotes DNA repair and contributes to radioresistance. We hypothesized that A2B receptor might be involved in the translocation of EGFR. Methods: We investigated whether A2B receptor is involved in EGFR translocation and DNA damage response (γH2AX/53BP1 focus formation) of lung cancer cells by means of immunofluorescence studies. Radiosensitivity was evaluated by colony formation assay after γ-irradiation. Results: A2B receptor was expressed at higher levels in cancer cells than in normal cells. A2B receptor antagonist treatment or A2B receptor knockdown suppressed EGFR translocation, γH2AX/53BP1 focus formation, and colony formation of lung cancer cell lines A549, calu-6 and NCI-H446, compared with a normal cell line (beas-2b). γ-Irradiation-induced phosphorylation of src and EGFR was also attenuated by suppression of A2B receptor expression. Conclusion: Activation of A2B receptor mediates γ-radiation-induced translocation of EGFR and phosphorylation of src and EGFR, thereby promoting recovery of irradiated lung cancer cells from DNA damage. General significance: Our results indicate that A2B receptors contribute to radiation resistance in a cancer-cell-specific manner, and may be a promising target for radiosensitizers in cancer radiotherapy.
KW - Adenosine receptor
KW - Cancer cell
KW - DNA damage
KW - Epidermal growth factor receptor
KW - Radiation
UR - http://www.scopus.com/inward/record.url?scp=85074478481&partnerID=8YFLogxK
U2 - 10.1016/j.bbagen.2019.129457
DO - 10.1016/j.bbagen.2019.129457
M3 - Article
C2 - 31678144
AN - SCOPUS:85074478481
VL - 1864
JO - Biochimica et Biophysica Acta - General Subjects
JF - Biochimica et Biophysica Acta - General Subjects
SN - 0006-3002
IS - 1
M1 - 129457
ER -