Effect of growth hormone on tumor and host in an animal model.
BACKGROUND
The relative effects of growth hormone on tumor versus host growth and protein metabolism are not known. This study examines the influence of recombinant rat growth hormone (r-rGH) on host and tumor growth, host body composition, and protein synthesis of tumor and host in tumor-bearing rats.


METHODS
After left flank implantation of methylcholanthrene-induced sarcoma, 28 Fischer rats with palpable tumor were treated with s.c. saline or 1 mg/kg/day r-rGH for 11 days. At death, fractional protein synthetic rates (FSRs) of tumor, liver, and gastrocnemius muscle were determined. In a separate experiment, 27 tumor-bearing rats received saline or 1 mg/kg/day r-rGH for 2 weeks. Tumor and host growth and host body composition were analyzed.


RESULTS
Animals treated with r-rGH had significantly higher liver FSR than did controls (233 +/- 27%/day vs. 110 +/- 4%/day, respectively). No significant differences were associated with growth hormone administration with respect to tumor growth, host composition, or FSR of tumor or muscle.


CONCLUSIONS
Growth hormone stimulates liver protein synthesis, without changing tumor growth, protein synthesis, or host composition in this rat sarcoma model. Further investigation of growth hormone as an anticachectic agent is warranted.
Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York 10021.
R F
RF
Wolf
B
B
Ng
B
B
Weksler
M
M
Burt
M F
MF
Brennan
D000818:Animals; D001823:Body Composition / Q000187:drug effects*; D002100:Cachexia / Q000188:drug therapy / Q000209:etiology*; D013006:Growth Hormone / Q000494:pharmacology*; D018482:Muscle, Skeletal / Q000187:drug effects / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D011994:Recombinant Proteins / Q000494:pharmacology; D012513:Sarcoma, Experimental / Q000378:metabolism / Q000503:physiopathology*
D011506:Proteins; D011994:Recombinant Proteins; D013006:Growth Hormone