TY - JOUR
T1 - Identification of the insulin-like growth factor binding proteins 5 and 6 (IGFBP-5 and 6) in human breast cancer cells
AU - Sheikh, M. Saeed
AU - Shao, Zhi Ming
AU - Clemmons, David R.
AU - Leroith, Derek
AU - Roberts, Charles T.
AU - Fontana, Joseph A.
PY - 1992/3/31
Y1 - 1992/3/31
N2 - Four estrogen receptor-positive (ER+) [MCF-7, T47D, ZR75 and BT474 ] and 3 ER- [Hs578T, MDA-MB-468 and MDA-MB-231] human breast cancer cell lines were examined for expression of the IGFBP-5 and IGFBP-6 genes. Northern blot analysis revealed that all cell lines, except MDA-MB-231, expressed IGFBP-5 mRNA. IGFBP-6 mRNA, however, was expressed only by the ER- cell lines. Western immunoblotting indicated that the previously unidentified 31-kDa and 32-kDa IGF binding species secreted by these cell lines are IGFBP-5. The levels of IGFBP-4 and IGFBP-5 were increased in MCF-7 cells by estradiol and IGF-I, respectively, indicating that these BPs may contribute to the growth stimulatory response to these mitogens.
AB - Four estrogen receptor-positive (ER+) [MCF-7, T47D, ZR75 and BT474 ] and 3 ER- [Hs578T, MDA-MB-468 and MDA-MB-231] human breast cancer cell lines were examined for expression of the IGFBP-5 and IGFBP-6 genes. Northern blot analysis revealed that all cell lines, except MDA-MB-231, expressed IGFBP-5 mRNA. IGFBP-6 mRNA, however, was expressed only by the ER- cell lines. Western immunoblotting indicated that the previously unidentified 31-kDa and 32-kDa IGF binding species secreted by these cell lines are IGFBP-5. The levels of IGFBP-4 and IGFBP-5 were increased in MCF-7 cells by estradiol and IGF-I, respectively, indicating that these BPs may contribute to the growth stimulatory response to these mitogens.
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U2 - 10.1016/S0006-291X(05)80290-6
DO - 10.1016/S0006-291X(05)80290-6
M3 - Article
C2 - 1373605
AN - SCOPUS:0026692729
SN - 0006-291X
VL - 183
SP - 1003
EP - 1010
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
IS - 3
ER -