PTCH1 and neoplasm: To test for autocrine activation of the Hh signaling pathway in tumor cells, we treated high SHH-expressing H2887 and HCC44 cells (Fig. 1c, d) with recombinant SHH (rSHH) 1 μg/ml, 5E1 10 μg/ml or KAAD-cyclopamine 300 nM and monitored the mRNA transcription of reported pathway target genes GLI1, PTCH1, HHIP, BMP4, BMP7, MYCN, CCND1, SOX9, and BMI1 by qPCR after treatment.