Higher susceptibility of erythropoietin-producing renal cell carcinomas to lysis by lymphokine-activated killer cells.

Erythropoietin production by renal cell carcinoma (RCC) is reported to be a potential marker for interleukin-2/interferon-alpha-responding tumor. We have investigated whether erythropoietin of RCC cells is involved in the immune recognition by lymphokine-activated killer (LAK) cells. Cells from primary culture of RCC cells expressing erythropoietin-mRNA or producing erythropoietin were more susceptible to lysis by LAK cells than those not expressing or producing it, respectively. RCC cells transfected with erythropoietin-cDNA became more susceptible to lysis by LAK cells than their erythropoietin-negative parental cells. These results indicate higher susceptibility of erythropoietin-producing RCC cells to lysis by LAK cells, suggesting that erythropoietin of RCC cells is involved in the immune recognition by LAK cells.