Figure 4. Effect of miR-148a expression on tumorigenicity of medulloblastoma cells.

(A-B) Y axis denotes the area of subcutaneous tumors formed over a period of 4-6 weeks in nude mice, post injection of doxycycline induced Daoy or D425 P2 polyclonal population (pTRIPZ-miR-148a) and vector (pTRIPZ) control population and after restoration of NRP1 expression in doxycycline induced P2 population of Daoy cells (n = 6 each). (D) shows photographs of these subcutaneous tumors. (F) shows bioluminescence images of nude mice orthotopically injected with D283 stable polyclonal population P1 expressing miR-148a upon doxycycline (DOX) induction and, firefly luciferse under CAG promoter. The images were captured on 1^st and 4^th week after the injection. (C) Y axis shows relative fold increase in the average radiance on 4^th week as compared to that on 1^st week after injection of D283 cells P1 population with (+DOX) or without doxycycline induction (Control) in 7 mice each. (G) shows photographs of hematoxylin-eosin stained paraffin sections of the orthotopic xenografts of control and doxycycline induced D283 cells P1 population. The area marked with rectangle in a & b shows invading margins of the tumor cells in the control and doxycycline induced miR-148a expressing cells; c & d show magnified images (400 X) of the invading margins indicated by rectangles in a & b.