ST6GAL1 and prostate cancer: As sialoglycans can play crucial roles in tumour immune evasion,7,71 and our findings above indicate ST6GAL1 can regulate Siglecs ligands in prostate cancer cells, we next utilised syngeneic models36,37 to investigate if sialic acid blockade in mice with a functional immune system can suppress prostate tumour growth and bone metastatic prostate cancer.