Fig. 1

miR-208a in pairs of serum samples from 30 lung cancer patients before and after radiotherapy and in lung cancer cells was examined by qRT-PCR. a The average serum miR-208a expression in 30 paired serum samples from lung cancer patients before and after radiotherapy. b qRT-PCR analysis of the expression of miR-208a in human lung cancer cell lines (A549, H1299, H1975 and H460) and non-cancerous bronchial epithelial cell lines (BEAS-2B and HBE). The relative expression levels of miR-208a in (c) A549, (d) H1299 and (e) HBE cells after exposure to 0, 2, 4 or 8 Gy X-ray irradiation. The relative serum miR-208a expression level normalized to miR-16 and cellular miR-208a expression normalized to U6 were calculated using the equation described in the Materials and Methods. *P < 0.05 and **P < 0.01 compared with the negative control