A compound of Formula I for use in a method of treatment of cancer by modulating the hedgehog signaling pathway: in which: Y 1 and Y 2 are independently selected from N and CH; R 1 is selected from cyano, C 1-6 alkyl, halosubstituted-C 1-6 alkyl, C 1-6 alkoxy, halosubstituted-C 1-6 alkoxy, dimethyl-amino, C 1-6 alkyl-sulfanyl and C 3-8 heterocycloalkyl optionally substituted with up to 2 C 1-6 alkyl radicals; R 2 and R 5 are independently selected from hydrogen, cyano, halo, C 1 - 6 alkyl, halosubstituted-C 1-6 alkyl, C 1-6 alkoxy, halosubstituted-C 1-6 alkoxy and dimethylamino; R 3 and R 4 are independently selected from hydrogen, halo, cyano, C 1 - 6 alkyl, halosubstituted-C 1-6 alkyl, C 1-6 alkoxy and halosubstituted-C 1-6 alkoxy R 6 and R 7 are independently selected from hydrogen, methyl, chloro, fluoro, bromo, trifluoromethyl and methoxy; with the proviso that R 6 and R 7 are not both hydrogen; and R 8 is selected from hydrogen, fluoro, chloro, methyl and trifluoromethyl; and R 9 is selected from -S 2 R 11, -C R 11, -NR 12a R 12b and -R 11; wherein R 11 is selected from thiomorpholino, sulfonomorpholino, sulfanomorpholino, morpholino, cyclohexyl, phenyl, azepan-1-yl, 2-oxopiperazin-1-yl, 1,4-oxazepan-4-yl, piperidin-1-yl, tetrahydro-2H-pyran-4-yl, piperidin-3-yl, piperazinyl, pyrrolidinyl and 1,4-diazepan-1-yl; and R 12a and R 12b are independently selected from isobutyl, hydroxy-ethyl, wherein said thiomorpholino, sulfonomorpholino, sulfanomorpholino, morpholino, cyclohexyl, phenyl, azepan-1-yl, 2-oxopiperazin-1-yl, 1,4-oxazepan-4-yl, piperidin-1-yl, tetrahydro-2H-pyran-4-yl, piperidin-3-yl, piperazinyl, pyrrolidinyl or 1,4-diazepan-1-yl of R 9 can be optionally substituted with 1 to 3 radicals independently selected from methyl, ethyl, methoxy, benzyl, thienyl-methyl, and pyridinyl-methyl, benzo[d][1,3]dioxol-6-yl and 2,3-dihydrobenzo[b][1,4]dioxin-7-yl, wherein said phenyl or benzyl substituent of R 9 is optionally substituted with 1 to 3 radicals independently selected from methoxy, ethoxy, methyl-piperazinyl, methyl, trifluoromethoxy, chloro, fluoro and trifluoromethyl; or a pharmaceutically acceptable salt or a stereoisomer, thereof; wherein said cancer is selected from: pancreatic cancer, prostate cancer, breast cancer, medulloblastoma, basal cell carcinoma and small-cell lung cancer. Y 1 and Y 2 are independently selected from N and CH; R 1 is selected from cyano, C 1-6 alkyl, halosubstituted-C 1-6 alkyl, C 1-6 alkoxy, halosubstituted-C 1-6 alkoxy, dimethyl-amino, C 1-6 alkyl-sulfanyl and C 3-8 heterocycloalkyl optionally substituted with up to 2 C 1-6 alkyl radicals; R 2 and R 5 are independently selected from hydrogen, cyano, halo, C 1 - 6 alkyl, halosubstituted-C 1-6 alkyl, C 1-6 alkoxy, halosubstituted-C 1-6 alkoxy and dimethylamino; R 3 and R 4 are independently selected from hydrogen, halo, cyano, C 1 - 6 alkyl, halosubstituted-C 1-6 alkyl, C 1-6 alkoxy and halosubstituted-C 1-6 alkoxy R 6 and R 7 are independently selected from hydrogen, methyl, chloro, fluoro, bromo, trifluoromethyl and methoxy; with the proviso that R 6 and R 7 are not both hydrogen; and R 8 is selected from hydrogen, fluoro, chloro, methyl and trifluoromethyl; and R 9 is selected from -S 2 R 11, -C R 11, -NR 12a R 12b and -R 11; wherein R 11 is selected from thiomorpholino, sulfonomorpholino, sulfanomorpholino, morpholino, cyclohexyl, phenyl, azepan-1-yl, 2-oxopiperazin-1-yl, 1,4-oxazepan-4-yl, piperidin-1-yl, tetrahydro-2H-pyran-4-yl, piperidin-3-yl, piperazinyl, pyrrolidinyl and 1,4-diazepan-1-yl; and R 12a and R 12b are independently selected from isobutyl, hydroxy-ethyl,