CD49a+ NK cells promote esophageal cancer development by inducing MDSCs infiltration via GM-CSF
摘要
Although extensive evidence indicates that tissue-resident natural killer (trNK) cells are closely related to the development and clinical outcomes of various tumours, their roles in esophageal cancer remain obscure.
MethodsTumour tissues collected from 54 esophageal squamous cell carcinoma (ESCC) patients during surgery and human ESCC tissue arrays including samples from 258 patients were subjected to analyse the phenotype and functions of immune cells.
ResultsWe observed a population of CD49a+ NK cells with a CD103hiCD69hi resident phenotype predominantly within the CD56bright NK cell subset in the intratumoral tissue of ESCC patients. These CD49a+ trNK cells, characterised by high expression of inhibitory receptors (TIM-3, CD244, TIGIT, PD-1), reduced cytotoxic potential (lower CD16, granzyme B, and perforin), and elevated secretion of IFN-γ and TGF-β, exhibited an exhausted and regulatory phenotype. Their presence was associated with poor prognosis in early-stage ESCC, but not in advanced stages. Mechanistically, these cells were found to enhance the immunosuppressive tumour environment by increasing MDSCs through GM-CSF secretion, thereby facilitating tumour progression.
ConclusionsOur research reveals that tumour-infiltrated CD49a+ NK cells exhibit exhausted and regulatory profile, capable of inducing the accumulation of MDSCs by secreting GM-CSF, and predict poor clinical outcomes in early-stage ESCC patients.