OBJECTIVE:

To study the effects of E2 on insulin-like growth factor binding protein-1 (IGFBP-1) and sex hormone-binding globulin (SHBG) production with cultured human HepG2 hepatoma cells.

DESIGN:

Experimental cell culture.

SETTING:

Academic medical center.

PATIENT(S):

None.

INTERVENTION(S):

Addition of E2 to cell culture medium.

MAIN OUTCOME MEASURE(S):

Intracellular and released concentrations of IGFBP-1 and SHBG.

RESULT(S):

Estradiol did not affect the intracellular or extracellular IGFBP-1 concentration, whereas the intracellular SHBG concentration increased significantly in response to 0.5-2.5 microM of E2.

CONCLUSION(S):

Whereas the two binding proteins share a number of regulatory factors, their regulation by E2 is dissimilar in human hepatoma cells. Estradiol does not affect the intracellular or secreted IGFBP-1 concentration, but it does increase the production of SHBG.