8). IL-10 has been shown to possess both anti- and pro-inflammatory roles in cancer (Ref. 9). The intensity of the immunological response to both self and foreign antigens is reduced by IL-10. In light of this, IL-10 signalling blockage improves vaccine-induced T-cell responses and tumour growth inhibition (Ref. 10). On the other hand, tumour regression is also induced by exogenous IL-10, particularly PEGylated (PEG)-IL-10 (Ref. 11). Here, IL10 is linked to cancer.