Does Arimidex lower IGF levels

[Nssca]

If so, is it a significant amount?
Is it anything to really worry about?
Thsnks

 

[bgmke7]

the study below is for postmenopausal breast cancer patients but it gives some indication as to what arimidex does to igf levels.now i doubt we are going to find a study done on healthy men lifting weights but i think that there maybe similar effects in men while taking arimidex.






Short-term effects of anastrozole treatment on insulin-like growth factor system in postmenopausal advanced breast cancer patients.

Ferrari L, Martinetti A, Zilembo N, Pozzi P, Buzzoni R, La Torre I, Gattinoni L, Catena L, Vitali M, Celio L, Seregni E, Bombardieri E, Bajetta E.

Nuclear Medicine, Istituto Nazionale per lo Studio e la Cura dei Tumori of Milan, Via G. Venezian, 1, 20133 Milan, Italy.

Insulin-like growth factors (IGFs) play a fundamental role in cancer development by acting in both an endocrinal and paracrinal manner, and hormone breast cancer treatments affect the IGF system by modifying circulating growth factor levels. We evaluated total IGF-1, IGF-2, IGF binding protein (IGFBP)-1 and IGFBP-3 in the blood of 34 postmenopausal advanced breast cancer patients (median age 63 years, range 41-85) treated with anastrozole, a non-steroidal structure aromatase inhibitor (NSS-AI). The plasma samples were obtained at baseline, and after 2, 4, 8 and 12 weeks of treatment. The IGFs were quantitated by means of sensitive radioimmunoassays (RIAs). IGF-1 significantly increased during anastrozole treatment (baseline versus 12 weeks, P=0.031), IGF-2 showed a trend towards an increase, and IGFBP-1 constantly but not significantly decreased; IGFBP-3 did not seem to be affected at all. The anastrozole-induced changes in IGFs and IGFBP-1 appeared to be different in the patients receiving a clinical benefit from those observed in non-responders. We have previously shown that letrozole (a different type of NSS-AI) modifies blood IGF-1 levels, and the results of this study of the biological effects of anastrozole on the components of the IGF system confirm our previous observations.

PMID: 11983488 [PubMed - indexed for MEDLINE]

 

[dragonfire101]

Int J Biol Markers. 2006 Apr-Jun;21(2):123-6. Links

Influence of bicalutamide with or without tamoxifen or anastrozole on insulin-like growth factor 1 and binding proteins in prostate cancer patients.

Boccardo F, Rubagotti A, Battaglia M, Zattoni F, Bertaccini A, Romagnoli A, Conti G. Department of Medical Oncology, National Cancer Research Institute and University of Genoa, Italy. [email protected]

BACKGROUND: There is growing evidence that IGF-1 and binding proteins may be involved in prostate cancer promotion and progression. PATIENTS AND METHODS: IGF-1 and binding proteins (IGFBP-1 and 3) serum levels were measured at baseline and after 3 and 6 months of treatment in a selected group of patients with prostate cancer who were randomly assigned to treatment with bicalutamide, bicalutamide plus anastrozole or bicalutamide plus tamoxifen in a comparative study investigating the role of pharmacological medication in the development of bicalutamide-induced gynecomastia. RESULTS: Bicalutamide monotherapy does not appear to alter the IGF-1/IGFBP system. In fact, the increase in IGF-1 levels induced by this treatment was paralleled by comparable increases in binding protein (IGFBP-3). No major changes from baseline up to month 6 either in IGF-1 or in IGFBP-1 and 3 were observed in the bicalutamide plus anastrozole arm. The addition of tamoxifen to bicalutamide produced a sharp decrease in IGF-1 levels (p<0.001) coupled with an increase in both IGFBP-1 (p=0.001) and, to a lesser extent, IGFBP-3 (p=0.5). CONCLUSIONS: The concurrent administration of tamoxifen and bicalutamide reduces the synthesis and bioavailability of IGF-1. Moreover, increased binding protein levels might exert antiproliferative and proapoptotic effects on prostate cancer cells, independently of the IGF-1/IGF receptor-mediated survival system. Both effects might have a synergistic inhibitory influence on prostate cancer growth.

PMID: 16847815 [PubMed - indexed for MEDLINE]

It appears tamoxifen will, but the results were not significant to say arimidex does.

 

[Nssca]

Thanks guys.

 

[bgmke7]

tamoxifen has been known and documented to lower igf-1 levels but the question was for arimidex(anastrozole)..............'
i also believe that the addition of bicalutamide in the above study is giving us a result that we are not looking for.bicalutamide is an anti-androgen and im thinking that it way be inhibiting the increase of igf-1 that you would get if anastrozole alone was used.





Short-term effects of anastrozole treatment on insulin-like growth factor system in postmenopausal advanced breast cancer patients.

Ferrari L, Martinetti A, Zilembo N, Pozzi P, Buzzoni R, La Torre I, Gattinoni L, Catena L, Vitali M, Celio L, Seregni E, Bombardieri E, Bajetta E.

Nuclear Medicine, Istituto Nazionale per lo Studio e la Cura dei Tumori of Milan, Via G. Venezian, 1, 20133 Milan, Italy.

Insulin-like growth factors (IGFs) play a fundamental role in cancer development by acting in both an endocrinal and paracrinal manner, and hormone breast cancer treatments affect the IGF system by modifying circulating growth factor levels. We evaluated total IGF-1, IGF-2, IGF binding protein (IGFBP)-1 and IGFBP-3 in the blood of 34 postmenopausal advanced breast cancer patients (median age 63 years, range 41-85) treated with anastrozole, a non-steroidal structure aromatase inhibitor (NSS-AI). The plasma samples were obtained at baseline, and after 2, 4, 8 and 12 weeks of treatment. The IGFs were quantitated by means of sensitive radioimmunoassays (RIAs). IGF-1 SIGNIFICANTLY INCREASED DURING ANASTROZOLE TREATMENT (baseline versus 12 weeks, P=0.031), IGF-2 showed a trend towards an increase, and IGFBP-1 constantly but not significantly decreased; IGFBP-3 did not seem to be affected at all. The anastrozole-induced changes in IGFs and IGFBP-1 appeared to be different in the patients receiving a clinical benefit from those observed in non-responders. We have previously shown that letrozole (a different type of NSS-AI) modifies blood IGF-1 levels, and the results of this study of the biological effects of anastrozole on the components of the IGF system confirm our previous observations.

PMID: 11983488 [PubMed - indexed for MEDLINE]

 

[cutt29]

aromatase inhibitors(armidex) increase IGF-1

the selective estrogenic action of Nolvadex lowers IGF-1

 

[Ashop]

on a different note i have heard letrozole increases igf1 levels