Fig. 8: Depletion of identified kinome abrogated the expression of miR-21 and novel targeting strategy for kinome-DDX23-miR-21 signaling during tumorigenesis.

a Specific knockdown of CDK1 abrogated the expression of miR-21 in luc-21-miRDREL-expressing A549 cells. The cells were infected with lentivirus expressing CDK1-specific shRNAs, and total RNA was prepared and subjected to northern blotting. The level of CDK1 was analyzed by western blotting after specific knockdown of CDK1 in the luc-21-miRDREL-expressing A549 cells. PSF, ACTB, and histone H3 (H3) were also analyzed as negative loading controls (bottom). b Specific knockdown of PLK1 abrogated the expression of miR-21 in the luc-21-miRDREL-expressing A549 cells. The cells were infected with lentivirus expressing PLK1-specific shRNAs, and total RNAs was prepared and subjected to northern blotting. The level of PLK1 was analyzed by western blotting after specific knockdown of PLK1 in the luc-21-miRDREL-expressing A549 cells. Symplekin (Sym) was also analyzed as a negative loading control (bottom). c Specific knockdown of SRC abrogated the expression of miR-21 in the luc-21-miRDREL-expressing A549 cells. The cells were infected with lentivirus expressing SRC-specific shRNAs, and total RNA was prepared and subjected to northern blotting. The protein level of SRC was analyzed by western blotting after specific knockdown of SRC in the luc-21-miRDREL-expressing A549 cells. PSF and ELAVL1/HuR (HuR) were also analyzed as negative loading controls (bottom). d Newly identified miR-21-processing inhibitor GW4064 with the miRDREL system is shown as blue oval. The pharmacological kinase inhibitors that modulate miR-21 processing identified with the miRDREL are also shown.