SMO and cancer: , the protein expression of the key molecules in HH signaling, including Sonic Hedgehog (SHH), Desert Hedgehog (DHH), PTCH1, Smoothened (SMO), and GLI1, was not observed in normal ovarian surface epithelium (OSE), but was increased stepwise in benign, borderline and malignant neoplasms [54], indicating that HH activity is relatively low in benign and borderline OC samples.