Scheme 1.

Experimental design: in vivo probiotic modulation of colorectal cancer. Four experimental groups were used in the present study (INT, control healthy group; P, probiotic-fed healthy group; DMH, control cancer group and DMH+P, probiotic-fed cancer group). Time schedule: probiotic usage as prophylactic (first four weeks, indicated by striped box – prevention period), followed by 15 weeks of DMH administration once a week (indicated by a stippled box) and a further 12-week period (from 19–31weeks), that was determined to be sufficient for tumour development. The arrows at the top indicate blood collection from the tail vein. An arrow at the bottom of the protocol indicates animal euthanasia at Week 31 at the conclusion of the experimental protocol.