HMOX1 and neoplasm: As showed in Fig. 2, HO-1 negative patients exhibited an average of 49.6% of tumor regression after radiotherapy, whereas high expression of HO-1 induced a great resistance to radiotherapy, with a significantly decreased tumor regression rate of 6.9% (P < 0.0005 vs HO-1 negative group); in between, treatment group with moderate HO-1 expression showed an average tumor regression of 29.1%.