Effect of fractioned irradiation on HIF-1alpha and MDR1 expression in esophageal cancer cells.
- Author:
Rui GAO
1
;
Guang-jian ZHANG
;
Jun-ke FU
;
Xin JIN
;
Ming-xin ZHANG
;
Fen LI
Author Information
- Publication Type:Journal Article
- MeSH: ATP Binding Cassette Transporter, Sub-Family B; ATP-Binding Cassette, Sub-Family B, Member 1; genetics; metabolism; Carcinoma, Squamous Cell; pathology; radiotherapy; Cell Line, Tumor; Dose Fractionation; Esophageal Neoplasms; pathology; radiotherapy; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; genetics; metabolism; RNA, Messenger; genetics; metabolism; Radiation, Ionizing
- From: Journal of Southern Medical University 2010;30(5):1037-1040
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo examine the effect of fractioned ionizing radiation on the expression of hypoxia inducible factor-1alpha (HIF-1alpha) and multidrug resistance (MDR1) in human esophageal cancer cells.
METHODSThe mRNA and protein levels of HIF-1alpha and MDR1 in esophageal caner EC9706 cells incubated in the presence of 150 micromol/L CoCl(2) were measured before and after the irradiation by quantitative RT-PCR and Western blotting, respectively. The chemosensitivity and radiosensitivity of the cells were analyzed by MTT assay and clone formation assay.
RESULTSMDR1 and HIF1alpha expressions were significantly up-regulated in the cells following hypoxia or irradiation (P<0.05). The surviving cell fraction in the exclusive irradiation group was significantly lower than that irradiation+hypoxia group (P<0.05). Compared with exclusive hypoxia group, MDR1 and HIF1alpha expressions were decreased significantly in irradiation+hypoxia group (P<0.05). HIF1alpha expression showed a positive correlation to MDR1 expression (P<0.01).
CONCLUSIONHypoxia is an important factor to induce resistance to chemo- and radiotherapy. Low-dose fractioned irradiation can lower MDR1 and HIF1alpha expressions in esophageal cancer cells, which should be considered when combining radiotherapy chemotherapy for esophageal cancer patients.
