Expression and immunolocalization of (A) ERCC1 and (B) β-tubulin isotype III in HEY cell line in response to cisplatin, paclitaxel and combination treatment. The images were evaluated using mouse monoclonal (green) and rabbit polyclonal (red) antibodies as described in the Materials and methods section. Cellular staining was visualized using secondary Alexa 488 (green) and Alexa 590 (red) fluorescent labelled antibodies. Nuclear staining was visualized using DAPI (blue) staining. Images are representative of three independent experiments. Magnification 200x; scale bar = 10 μM. (C) The mean fluorescence intensity was quantified using Cell-R software (Olympus Soft Imaging Solutions). Significant variations between the groups are indicated by ** P < 0.01, *** P < 0.001.