A Study Of The Effects Of Enhanced Radiosensitivity Of Solid Tumours In Mice Treated With RhEPO Concentration Oxygen

Objective To investigate the effects of enhanced radiosensitivity of solid tumours in anaemic mice treated with recombinant human erythropoietin combining Carbogen plus low concedtration oxygen.Meterials and Methods Kun Ming mice were divided into three groups;Group A, also group of rhEPO +CPLCO (using rhEPO and inhalation of carbogen for 5 minutes before the irradiation, then switched to inhalation of low concentration Oxygen right at the beginning of irradiation, and continued till the end of irradiation). Group B,also group of CPLCO (inhalation of carbogen for 5 minutes before the irradiation, then switched to inhalation of low concentration oxygen right at the beginning of irradiation, and continued till the end of irradiation ). Group C,also control group (inhalation of air before and during irradiation) Group A, animals were treated with rhEPO three times per week from 9 days before tumour implantation and up until the day of irradiation for 2 weeks. Carboplatin was administered On day -3 and tumours were irradiated On day 5. Group B and C, Carboplatin was administered on day-3 and tumours were irradiated on day 5. Murine tumours were irradiated with 6MV X -rays a sing time with a single dose of lOGy. After irradiation, all the tumours were measured qod for two weeks. At last, after the mice were killed, some tumors in every group were maintained. After routine histological processing, transverse sections were cut and' stained with haematox-ylin and eosin.Results The rate of the regrowth of the tumors in group A is slower than that of the tumors in group B or C, resulting in a growth delay (PO. 02, P<0. 05). Group B compared with group C, the difference of the regrowth of the tumors is not obvious (P 0. 05). The volume doubling time of group A is longer than that of group B or C (group A; 15. 2 days, B:12. 9days, C;10days). The image of transverse sections indicated Group A, tumor cells necrosed obviously and extensively, only minor nucleola of the cells were survived,and organization was repaired obviously.Conclusions The correction of chemotherapy-induced anaemia by rhEPO treatment combining CPLCOR increases murine tumor radiosensitivity, and it is valuable administering and promoting it in tumor patients.