Future studies should examine the possible reasons behind a difference in PEDF expression patterns between the genders and tumour location and assess cellular function on a range of colorectal cancer cell lines (including metastatic and mucinous adenocarcinoma) and to explore the effect of cellular function in in vivo models using colorectal tumour xenografts within animal models. This evidence concerns the gene SERPINF1 and mucinous adenocarcinoma.