Packed Red Blood Cell Supernatants Do Not Promote Growth or Cisplatin Resistance of Myeloid Leukemia K-562 Cells

BACKGROUND: A decreased immune surveillance as a consequence of packed red blood cell (PRBC) transfusions has been linked to cancer recurrence and progression, but a causal mechanism remains unclear. During processing and storage of PRBC, numerous bioactive substances accumulate in the acellular fraction (supernatant) of PRBC. AIM: The study aimed to determine whether the supernatant of leukocyte-reduced (LR) and non-leukocyte-reduced (NLR) long-stored PRBC can modulate the survival and proliferation of myeloid leukemia K-562 cells, and the influence of cisplatin (cisPt) on these processes. METHODS: Viability, proliferation, DNA damage, intracellular reactive oxygen species (ROS), caspase-3/7 and caspase-9 levels were determined in response to the LR or NLR, fresh (day 1) and long-stored (day 42) PRBCs. RESULTS: The supernatants of fresh (day 1) and stored (day 42) PRBC, in the absence and presence of cisPt, promoted apoptosis of K-562 cells via the increased production of reactive oxygen species (ROS) and increased level of DNA damage, which was manifested by the viability reduction and inhibition of K-562 cell proliferation. No significant influence of the pre-storage leukocyte-filtration and storage time of PRBC units on their anti-proliferative effect was demonstrated. CONCLUSION: The findings may suggest that the PRBC acellular fraction does not affect chronic myeloid leukemia (CML) progression. However, these issues are pioneering and require further study.