Our study shows that the small-molecule inhibitor that targets Caspase-1 has promising anti-tumour effects, inhibiting breast cancer bone metastasis: preventing metastatic outgrowth in the bone and reducing spontaneous metastasis to this site to the same extent or better than the IL1R antagonist, Anakinra (Figure 3E and Figure 4E), whilst having less impact on immunity (Figure 6). Here, CASP1 is linked to neoplasm.