SLIT2 and cancer: Similar low expression levels of miR-218, SLIT2and SLIT3 were obtained in lung cancer tissues when compared to normal lung tissues (the fold change of miR-218 in cancer vs. normal = 0.29, p = 4.4 × 10−16, Fig. 1d; the fold change of SLIT2 in cancer vs. normal = 0.10, p = 1.8 × 10−15, Fig. 1e; the fold change of SLIT3 in cancer vs. normal = 0.08, p = 8.9 × 10−16, Fig. 1f).