Novel Alternative Approach to Inhibiting Insulin Growth Factor (IGF) May Provide New Treatment for Breast Cancer and Other Cancers.

Potential to halt cancer cell growth without interfering with insulin may address limitations of current IGF inhibitors

SAN FRANCISCO, Oct. 25 /PRNewswire-FirstCall/ -- Cell Therapeutics, Inc. (CTI) (Nasdaq and MTAX: CTIC) and Systems Medicine, LLC (SM), a wholly-owned subsidiary of CTI, announced that preclinical data presented at the 19th annual AACR-NCI-EORTC Symposium show an antibody to IGF-II may solve the problems of low blood sugar associated with drug candidates working through insulin receptor-linked pathways. The data presented is part of CTI's ongoing Cooperative Research and Development Agreement (CRADA) with the National Cancer Institute (NCI) to develop products targeting the IGF pathway.

"While insulin-related growth factors play an important role in normal glucose metabolism and cell growth, the IGF pathway is increasingly being recognized as a critical contributor to growth of certain types of cancers," said Jack W. Singer, M.D., Chief Medical Officer of CTI. "Many of the current approaches target blocking the IGF receptor or inhibition of post receptor kinases in an attempt to slow or kill tumor cell growth and are often associated with inhibition of insulin's important metabolic functions including maintaining normal blood glucose levels. By developing an antibody that binds to and neutralizes a specific form of insulin growth factor (IGF- II) the anti-tumor benefit may be retained without blocking the insulin receptor or associated post receptor signaling pathways, potentially allowing normal blood glucose and metabolic control."

Depleting soluble ligand (IGF-II) in solid tumor (human breast cancer xenograft) by ligand-specific human monoclonal antibody (Abstract #A59)

Dimiter S. Dimitrov, Ph.D., Head of the Protein Interaction Group of the CCR Nanobiology Program at the NCI's Center for Cancer Research and principal investigator for the NCI on the CRADA, presented data that may provide the first proof-of-concept that human monoclonal antibodies (hmAbs) can decrease the concentration of soluble ligands in tumors, suggesting that targeting ligands of growth factors could be a useful strategy for treatment of solid tumors. The data show that the hmAb m610, which recognizes the mature and the premature forms of IGF-II, is most extensively characterized and was evaluated in an in vivo MCF-7 cell-based mouse xenograph model to test the hypothesis that high levels of soluble ligand-specific antibody in the blood could shift the quasi-equilibrium distribution of the ligand between the blood and the tumor resulting in a decreased ligand concentration in the tumor.

"These data are important because targeting the ligands of growth factors such as IGF-II could play an important role in the treatment of patients with solid ...