Next, studying gene expression of the major check-point molecules (PD1, PD-L1, CTLA4) across the identified 4 subgroups, we found that PD1 and PDL1 were significantly more expressed in IIH-FH tumours than in those defined as IIL-FL, while no differences in CTLA-4 were detectable (Fig. 3b). This evidence concerns the gene CTLA4 and neoplasm.