Fig. 6: Crosstalk between SHH and CMKLR1 pathways underlies in vivo development of MB.

A–D Daoy cells were modified to express luciferase and further infected with lentiviruses expressing control, CMKLR1- or PRKACA-targeted shRNAs. Cells were then used for s.c. injection of male nude mice (n = 5). The development of xenograft tumors was visualized on indicated days via bioluminescence imaging (A), and the tumor bioluminescence signals in mice were recorded to follow tumor progression (B). On day 28 post-inoculation, mice were sacrificed, tumors were isolated (C) and the tumor volume was quantified (D). E Smo-transgenic mice received intracerebellar injection with shRNA-expressing recombinant adenoviruses (1 × 10¹² PFU/ml, 2.5 μl) upon onset of tumors. The survival of mice were recorded daily for preparation of a Kaplan–Meier curve (n = 10). P = 0.0029 (shNC v.s. shCMKLR1) and P = 0.0365 (shCMKLR1 v.s. shCMKLR1+shPRKACA). F, G Tumors were isolated from transgenic mice that spontaneously develop Smo-driven MB (lower panel, n = 5), and normal cerebella were isolated from age-matched wild-type mice (upper panel, n = 5). The specimens were sectioned and subject to IHC staining for indicated proteins (F) and quantification of the staining results by H-score (G). NM, normal tissue. Bar, 100μm. H, I Representative images for immunohistochemical assays of clinical non-SHH (upper panel, n = 5) and SHH (lower panel, n = 5) MB samples (H). SHH subtype MB was distinguished by positive staining for GAB1 in IHC, and quantification of the staining results by H-score (I). Bar, 100μm. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001, n.s., non-significant.