[Experimental chemoendocrine therapy of human breast carcinoma xenograft serially transplanted into nude mice].
The antitumor effect of combined chemoendocrine therapy with tamoxifen (TAM) and 5-fluorouracil (5-FU) on breast carcinoma xenograft (R-27), serially transplanted into the nude mice, was examined from the aspect of estrogen receptors (ER) and cytological features. The mice were given 6 intramuscular injections of TAM (5mg/kg) at 3-day intervals (TAM group), 3 intraperitoneal injections of 5-FU (60 mg/kg) at 4-day intervals ((5-FU group), or a combination of the two drugs (combined group). When the tumor was resected on 21 days after the initial treatment, the ER were assayed and %S was determined by flowcytometry. Furthermore, proliferative cell nuclear antigen (PCNA) was stained, and the stained cells were counted. A synergistic antitumor effect of TAN and 5-FU was found in mice given combined therapy. Reduction in the ER level was more marked in this group than in the others, but there were no significant differences in the %S value or the ratio of PCNA positive cells among the three treated groups. These results suggest that the combined effect of TAM and 5-FU has no relation to the inhibition of DNA synthesis.
Watanabe
O
O
Department of Surgery, Tokyo Women's Medical College Daini Hospital.
D000818:Animals; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000276:immunology / Q000378:metabolism; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D009687:Nuclear Proteins / Q000378:metabolism; D018809:Proliferating Cell Nuclear Antigen; D011960:Receptors, Estrogen / Q000378:metabolism; D013629:Tamoxifen / Q000008:administration & dosage
D009687:Nuclear Proteins; D018809:Proliferating Cell Nuclear Antigen; D011960:Receptors, Estrogen; D013629:Tamoxifen; D005472:Fluorouracil