Pretreatment with cisplatin plus hyperthermia kills different tumor cells but preserves the erythrocyte function in the intra-operative blood salvage in vitro

Abstract

To investigate the effects of cisplatin plus hyperthermia on erythrocytes and killing human hepatocarcinoma (HepG2), gastro carcinoma (SGC7901) and colonic carcinoma (SW620) cells in the intra-operative blood salvage from cancer surgery in vitro. HepG2, SGC7901 or SW620 cells were mixed into the aliquot of erythrocyte concentrated from each intra-operative blood salvage of 30 patients subjected to gastrointestinal cancer surgery. The mixture cells were divided into the following groups (n = 30): A group (37 °C); B group (42 °C); C, D, E groups (50, 100, or 200 µg/ml DDP); F, G, H, I groups (42 °C, 25, 50, 100, or 200 µg/ml DDP). After treating for 60 min, tumor cells and erythrocytes were separated by density gradient centrifugation. The Na(+)-K(+)-ATPase activity, cell count, osmotic fragility, and blood gas variables were determined in erythrocytes. Cell viability and colony formation were determined in tumor cells. Compared with A [(0.30 ± 0.08) µmol Pi/10(7)/h], the Na(+)-K(+)-ATPase activity was significantly decreased in E, H and I groups [(0.24 ± 0.07), (0.25 ± 0.06) and (0.24 ± 0.07) µmol Pi/10(7)/h] (P < 0.05). Extra-erythrocytic K(+) in E, H and I groups [(2.16 ± 0.37), (2.16 ± 0.38) and (2.56 ± 0.50) mmol/L] were significantly increased compared with A group [(1.53 ± 0.43) mmol/L] (P < 0.05). Compared with A group, osmotic fragility in E, H and I groups was significantly increased (P < 0.05). Among B, C, D, E, F, G groups, only in G group colony formations of HepG2, SGC7901, and SW620 (0% ± 0%, 0% ± 0% and 0.01% ± 0.01%) at 14 d were completely inhibited (P < 0.01) compared with A group (78.54% ± 7.83%, 72.28% ± 6.58% and 66.69% ± 6.69%). Pretreatment with cisplatin (50 µg/ml) plus hyperthermia (42 °C) for 60 min in vitro might be an effective strategy to clear tumor cells contamination but preserve erythrocytes, which is worthy to be optimized and used in the intra-operative blood salvage in cancer surgery.