Fig. 1
![Fig. 1](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs12929-016-0219-6/MediaObjects/12929_2016_219_Fig1_HTML.gif)
VEGF overexpressed in the sera of the enrolled patients with colorectal cancer. a Total 34 pairs of clinical tissues from the enrolled patients were stained using methylene blue staining and distinguished by a pathologist. The healthy volunteers were not tested due to ethical issues, who had no evidence of known CRC. NT: non-tumor; T: tumor. Scale bar: 100 μm. b VEGF levels were increased in the sera of patients with colorectal cancer (n = 34) compared to that in healthy volunteers (n = 15). *p < 0.05