SFRP1 and neoplasm: Further work is necessary to confirm SFRP1 as a suppressor of mammary tumour progression in the dog similarly to its tumour suppressive role in human breast cancer; to test whether a reduction in SFRP1 leads to an activation of canonical and/or non-canonical Wnt-signalling pathways in canine cancer; and to find out whether CMTs with low SFRP1 may respond to Wnt-inhibiting drug treatment with e.g. SFRP1-mimicking peptides [57].