Fig. 6

Expression of Shh and Nrf2 in blood and tissue samples based on CTCs. A Shh expression was quantified by qRT-PCR normalized against GAPDH in blood samples of HNSCC patients and compared with healthy control. B, C qRT-PCR was used to measure Shh expression in study subjects’ blood and tissue samples, normalized against GAPDH. The results were compared between patients who tested positive for CTC and those who did not. D, E qRT-PCR was used to quantify Shh expression in both CTC-positive and CTC-negative HNSCC patients. The results were normalized against GAPDH and compared between tissue and blood samples. F The expression of Nrf2 was measured in blood samples from study participants using qRT-PCR, normalized against GAPDH, and compared to healthy control subjects. G, H The expression of Nrf2 was also measured in study subjects’ blood and tissue samples using qRT-PCR, normalized against GAPDH, and compared between patients who tested positive for CTC and those who tested negative. I, J Quantitative real time PCR was carried out to determine Nrf2 expression in both blood and tissue samples from patients with HNSCC who were CTC-positive and negative, normalized against GAPDH. Data represented as mean ± SD and the Mann–Whitney test was carried out to compare Shh and Nrf2 expression among the study subjects. **p-value < 0.01, ****p-value < 0.0001, two-tailed unpaired t-test (Mann–Whitney test)