Expression of the Sonic Hedgehog Embryonic Signalling Pathway Components in Matched Pre-Treatment and Relapsed Small Cell Lung Cancer Biopsies

Abstract Cancer stem cells may be responsible for tumour regrowth and acquisition of resistance in small cell lung cancer (SCLC). The Hedgehog pathway regulates survival and proliferation of tissue progenitor and stem cell populations, promoting the expression of stem cell related and proliferative genes. We evaluated the Sonic Hedgehog (Shh) embryonic signalling pathway in relapsed SCLC. Expression levels of Shh related genes GLI1, SMO, SUFU, PTCH1, HHIP, BCL2, BMI, ZEB1, ZEB2, N-MYC, Twist1 were analysed by qRT-PCR in matched pre-treatment and relapsed tumour fresh frozen biopsies of three SCLC patients. Expression of each gene was compared using the paired samples t-test, as well as comp…