Human Neutrophil Peptides 1-3--early markers in development of colorectal adenomas and carcinomas.

Expression of Human Neutrophil Peptides (HNP) 1-3 was recently found to be associated with development of colorectal cancer. Raised defensin-expression in tumours is believed to stem from increased infiltration of neutrophils into tumour environment. To further specify the role of alpha-defensins in tumourigenesis and progression, HNP1-3 were analyzed in colorectal adenomas and carcinomas of 87 patients and quantified in relation to cancer stage and grading. Using the ProteinChip arrays, HNP1-3 were found upregulated in both colorectal adenomas and carcinomas. By combining the array with Laser capture microscopy we were able to confirm that HNP1-3 are expressed by tumour cells but not by neutrophils or other tumour invading cells. These findings suggest that alpha-defensins are more likely to contribute to tumour growth than they are to mount an effective host anti-tumour response. However, the amount of HNP-expression was not found to be related to tumour stage, grading, and serological tumour markers.