Abstract
We recently found evidence indicating that the source of elevated serum insulin-like growth factor binding protein (IGFBP)-2 in leukemia was the leukemic T-cells. Here we report that locally produced IGF-II affects IGFBP-2 expression and growth of leukemic cells through the IGF type I receptor. We measured IGFBP-2, -4 and IGF type I receptor (IGF-I-R) mRNA by RT-PCR, cell growth and IGFBP-2 secretion (per 10(6) cells). IGF-I-R binding sites were assessed by 125I-IGF replacement studies. Inhibition using an IGF-II antibody showed that tumor cell-derived IGF-II accounts for a significant 25% (P < 0.001) increase in IGFBP-2 secretion and enhanced growth (P < 0.01) of leukemic T-cells after 7 days in culture. IGFBP-2 secretion, but not IGFBP-2 mRNA was specifically increased by IGFs, while no specific effect of insulin was detectable. The addition of 100 ng/ml IGF-II enhanced the IGFBP-2 secretion 2.8-fold, while the use of IGF-I only enhanced IGFBP-2 secretion 1.7-fold, although IGF-I enhanced IGF-II action. Through inhibition using JB1, a peptide inhibiting the IGF signal transduction by blocking the IGF-I-R, we demonstrated the involvement of the IGF-I-R in IGFBP-2 and -4 expression and leukemic cell growth. However, only slight...Continue Reading
Citations
Jun 18, 2009·Cancer Causes & Control : CCC·Anna Carita Callan, Elizabeth Milne
May 6, 2004·Growth Hormone & IGF Research : Official Journal of the Growth Hormone Research Society and the International IGF Research Society·T Zimmermann-BelsingU Feldt-Rasmussen
Feb 20, 2004·Placenta·Debabrata GhoshJayasree Sengupta
Mar 23, 2004·Placenta·A T FazleabasZ Strakova
Jun 14, 2005·Placenta·G NieL A Salamonsen
Jul 26, 2002·Fertility and Sterility·Peter LichtLudwig Wildt
Sep 25, 2003·Fertility and Sterility·Xiaoyan QiuKristina Gemzell-Danielsson
Jun 28, 2003·Placenta·P K Lala, C Chakraborty
Jun 14, 2003·Leukemia Research·Peter VorwerkUwe Mittler
Oct 27, 1999·Regulatory Peptides·M W ElmlingerW Kiess
Apr 28, 2001·Molecular and Cellular Endocrinology·M W ElmingerM B Ranke
Jan 22, 2003·Animal Reproduction Science·S Schäfer-Somi
Aug 14, 2003·Growth Hormone & IGF Research : Official Journal of the Growth Hormone Research Society and the International IGF Research Society·Anders Juul
Nov 20, 2003·Growth Hormone & IGF Research : Official Journal of the Growth Hormone Research Society and the International IGF Research Society·Cheryl A Conover, Sundeep Khosla
Mar 8, 2007·Neuropsychopharmacology : Official Publication of the American College of Neuropsychopharmacology·Jessica E MalbergSharon Rosenzweig-Lipson
Sep 9, 2005·Pediatric Research·María Sonia BaquedanoAlicia Belgorosky
Oct 2, 2013·Endocrine-related Cancer·Callum Livingstone
Sep 9, 2011·Leukemia Research·Andrea KühnlClaudia D Baldus
Jul 20, 2007·Pediatric Blood & Cancer·Kristin DawczynskiFelix Zintl
Jan 27, 2015·Journal of Cell Communication and Signaling·Steven W YauVincenzo C Russo
Feb 18, 2014·Biochimica Et Biophysica Acta·Gustavo Monteiro EscottE S Loss
May 31, 2001·Clinical Endocrinology·J Van DoornS C Van Buul-Offers
Jan 31, 2006·Bone Marrow Transplantation·K DawczynskiF Zintl
Mar 4, 2018·Scientific Reports·Dongfang TangWen Gao
Apr 25, 2000·Biology of Reproduction·T S GaddD C Wathes