PMID- 2501022
OWN - NLM
STAT- MEDLINE
DCOM- 19890825
LR  - 20111117
IS  - 0008-5472 (Print)
IS  - 0008-5472 (Linking)
VI  - 49
IP  - 15
DP  - 1989 Aug 1
TI  - Growth factor binding to 7,12-dimethylbenz(a)anthracene-induced mammary tumors 
      from rats subject to chronic caloric restriction.
PG  - 4135-41
AB  - Caloric restriction (CR) inhibits tumorigenesis in rodents. To understand the 
      basis for this effect the binding of insulin, insulin-like growth factor 
      I/somatomedin C (IGF-I/Sm-C), insulin-like growth factor II/multiplication 
      stimulating activity (IGF-II/MSA), and epidermal growth factor were examined to 
      membrane preparations of 7,12-dimethylbenz(a)anthracene-induced mammary 
      adenocarcinomas and several normal tissues from female Sprague-Dawley rats. 
      Animals were fed ad libitum (AL) or 25% and 40% calorically restricted diets. 
      Large, palpable (LP) and small, less than or equal to 100 mg, nonpalpable (SNP) 
      tumors were evaluated. Growth factor binding to tumors was differentially 
      affected by CR. IGF-I/Sm-C binding was comparable for AL-LP, AL-SNP, and 25% 
      CR-LP tumors, but elevated in 25% CR-SNP tumors. Scatchard analysis revealed high 
      and low affinity IGF-I/Sm-C binding sites, with AL-SNP and 25% CR-SNP tumors 
      exhibiting similar levels of high affinity sites and at a greater concentration 
      than AL-LP and 25% CR-LP tumors. Insulin binding to mammary tumors was low, i.e., 
      8- to 13-fold lower than IGF-I/Sm-C binding. The 25% CR-LP and SNP tumors bound 
      2- to 5-fold more insulin than corresponding AL-LP and SNP tumors. Binding of 
      IGF-II/MSA to these tumor preparations was high, approximately 11- to 25-fold 
      greater than insulin binding, and was unaffected by CR or tumor size. The binding 
      of epidermal growth factor was not detected in any tumor preparations. Receptor 
      binding studies were confirmed with covalent cross-linking and sodium dodecyl 
      sulfate-polyacrylamide gel electrophoresis analyses. Normal tissues exhibited 
      tissue- and growth factor-specific alterations in binding with host CR. Thus, 
      alterations in growth factor binding were not tumor specific, but were less 
      pronounced than in mammary tumors. These findings suggest alterations in 
      IGF-I/Sm-C and insulin binding properties to tumors in relation to CR and tumor 
      size may contribute, in part, to the inhibitory effects of CR on tumorigenesis.
FAU - Ruggeri, B A
AU  - Ruggeri BA
AD  - Wistar Institute of Anatomy and Biology, Philadelphia, Pennsylvania 19104.
FAU - Klurfeld, D M
AU  - Klurfeld DM
FAU - Kritchevsky, D
AU  - Kritchevsky D
FAU - Furlanetto, R W
AU  - Furlanetto RW
LA  - eng
GR  - CA-09485/CA/NCI NIH HHS/United States
GR  - CA-38981/CA/NCI NIH HHS/United States
GR  - CA-43856/CA/NCI NIH HHS/United States
GR  - etc.
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Cancer Res
JT  - Cancer research
JID - 2984705R
RN  - 0 (Insulin)
RN  - 0 (Somatomedins)
RN  - 57-97-6 (9,10-Dimethyl-1,2-benzanthracene)
RN  - 62229-50-9 (Epidermal Growth Factor)
RN  - 67763-96-6 (Insulin-Like Growth Factor I)
RN  - 67763-97-7 (Insulin-Like Growth Factor II)
SB  - IM
MH  - 9,10-Dimethyl-1,2-benzanthracene
MH  - Animals
MH  - *Energy Intake
MH  - Epidermal Growth Factor/*metabolism
MH  - Female
MH  - Insulin/*metabolism
MH  - Insulin-Like Growth Factor I/*metabolism
MH  - Insulin-Like Growth Factor II/*metabolism
MH  - Mammary Neoplasms, Experimental/chemically induced/*metabolism/prevention & 
      control
MH  - Rats
MH  - Rats, Inbred Strains
MH  - Somatomedins/*metabolism
EDAT- 1989/08/01 00:00
MHDA- 1989/08/01 00:01
CRDT- 1989/08/01 00:00
PHST- 1989/08/01 00:00 [pubmed]
PHST- 1989/08/01 00:01 [medline]
PHST- 1989/08/01 00:00 [entrez]
PST - ppublish
SO  - Cancer Res. 1989 Aug 1;49(15):4135-41.