We next cloned an ERE-LUC-mut construct carrying a substitution of six nucleotides within the core seed sequence of ERβ (Fig. 5d), and observed that CLPTM1L failed to promote the activity of ERE-LUC-mut in NSCLC and HEK293T cells (Fig. 5e and Additional file 1: Fig. S5C). This evidence concerns the gene ESR2 and non-small cell lung carcinoma.