KLRK1 and neoplasm: Treatment of healthy donor NK cells with obese tumour conditioned media (TCM) resulted in significantly lower frequencies of activating receptor expressing NK cells; NKp30: untreated versus obese TCM (74.9% vs. 30.73%, p = 0.04), 24 h non-obese TCM versus 24 h obese TCM (86.83% vs. 30.73%, p = 0.0066), NKp46: untreated versus 24 h obese TCM (74.87% vs. 40.8%, p = 0.02), NKG2D: untreated versus 24 h obese TCM (82.26% vs. 53.2%, p = 0.03) (Fig. 1d).