SELL and neoplasm: Although recent experimental data indicate that lymphocyte L-selectin–tumour cell interaction is of importance in colon metastasis formation as well (Resto et al, 2008; Thomas et al, 2008, 2009), it was not the subject of this study as homozygous scid mice contain few if any lymphocytes (Bosma et al, 1983), implying that L-selectin expression present on lymphocytes is not an immediate concern in our xenograft model.