Changes in oxygen metabolism in solid tumors by administration of artificial oxygen carriers

体外肾肿瘤模型的建立：将LY80肿瘤接种于大鼠左肾被膜下间隙。用Parafilm包裹可防止肿瘤向周围组织渗透。6天后，左肾静脉和腹主动脉置管。右肾动脉，左肾动脉分叉处近端结扎主动脉。这样，左肾肿瘤的循环就被隔离了。我们观察到，当肿瘤被含氧的人工氧载体灌流时，肿瘤组织的氧分压增加。通过采集动脉和静脉血，我们将能够估计肿瘤组织内的氧气消耗。动脉注射rHSA-FecycP对肿瘤组织的氧合作用：肿瘤组织氧分压在开始给药5分钟后开始升高，并持续升高15分钟。基于这一发现，由于使用我们的照射器照射20Gy光至少需要15分钟，我们决定同时开始照射和输注。rHSA-FecycP联合放射治疗：联合治疗组的局部肿瘤控制优于单独放射治疗。肿瘤氧合是否是这种协同作用的唯一机制还有待商榷。对生存的影响需要进一步评估。

Establishment of isolated renal tumor model : In rats, LY80 tumor was inoculated in the subcapsule space of the left kidney. Wrapping with Parafilm prevented tumor infiltration into the surrounding tissue. After 6 days, the left renal vein and the abdominal aorta was cannulated. Right renal artery, and the aorta was ligated proximal to the bifurcation of left renal artery. In this way, the circulation of the left renal tumor was isolated. We observed an increase in tumor tissue oxygen tension, when the tumor was perfused with oxygenated artificial oxygen carrier. By sampling arterial and venous blood, we will be able to estimate the oxygen consumption within tumor tissue. The model needs to be further refined in order to achieve this objective.Oxygenation of tumor tissue by intraarterial infusion of rHSA-FecycP : Tumor tissue oxygen tension started to rise 5 minutes after the start of infusion, and remained elevated for 15 minutes. Based on this finding, since it takes at least 15 minutes to irradiate 20Gy using our irradiator, we decided to start irradiation and infusion simultaneously.Combination of rHSA-FecycP with radiation : Local tumor control was superior in the combination group compared with radiation alone. It was questionable whether tumor oxygenation was the only mechanism for this synergy. The impact on survival needs further evaluations.