Interestingly, Sicking et al. evaluated the association between an acute systemic immune response (elevated serum CRP) and gene expression of immune markers of the TME at the mRNA level: they observed no significant correlations between peripheral blood CRP levels and mRNA expression of key markers associated with inflammation (e.g., IL-6 and IL-8), immune response or proliferation in breast cancer tissue [26]. Here, IL6 is linked to breast cancer.