CD300LD and neoplasm: Key points about CD300ld and MDSCs include the following: (1) CD300ld acts as a receptor on PMN-MDSCs, facilitating their recruitment to tumors and enhancing their ability to suppress T cell activity, promoting tumor growth; (2) Research indicates that high CD300ld expression on MDSCs is linked to poor prognosis in various cancers, making it a potential biomarker for tumor aggressiveness; (3) Targeting CD300ld through blocking antibodies could be a strategy to inhibit MDSC function and enhance anti-tumor immune responses, potentially improving the efficacy of cancer immunotherapy [39].