TLR2 and neoplasm: Melanoma cells change the glycocalyx structure on their heparan sulfate proteoglycan, which can bind to TLR2 on MDSCs and facilitate the recruitment of MDSCs via the TLR2/MyD88/IL‐6/STAT3 pathway, leading to the inhibition of NK cell recruitment and cytotoxicity and ultimately tumor progression and metastasis (97).