CD44 and lung cancer: The levels of the Sp1-regulated candidate miRNAs targeting CD44, β-catenin and ALDH1, i.e., miR-3194-5p, miR-218-5p, miR-200-5p, miR-193a-5p, miR-182-5p and miR-135-5p, were studied in A549-T24 and E2-A549 lung cancer cells (Fig. 8B, C and Additional file 5: Fig. S5).