Finally, to explore whether there is also an association between our proteomic subtypes and CMS subtyping,16 we made a retrospective analysis of 45 FFPE CRC tumour samples (Table S2) and, after their classification into CMS subtypes by IHC as described by Trinh et al,14 the expression of SERPINA1 and SRSF3 was evaluated by IHC in each of CMS1, CMS2/3 and CMS4 subtypes (Figure S4). Here, SERPINA1 is linked to colorectal carcinoma.