COL18A1 and lung carcinoma: Although, no significant difference was found in the hypoxic area on day 3, treatment of rh-endostatin resulted in less hypoxic area, as assessed by pimonidazole staining on day 6 and day 9 in A549 lung carcinoma compared with NS controls (p = 0.002 and p = 0.0093, respectively, Fig. 5A and D).