Multiple myeloma is characterized by the accumulation of malignant plasma cells in thebone marrow. Significant progress in molecular mechanisms of signaling pathways underlying the survival and/or proliferation of the...Multiple myeloma is characterized by the accumulation of malignant plasma cells in thebone marrow. Significant progress in molecular mechanisms of signaling pathways underlying the survival and/or proliferation of these cells has been achieved. Interleukin 6 （IL-6） is an important cytokine leading to multiple myeloma （MM） cells growth and survival. However, some MM cells isolated from MM patients are poorly responsive to IL-6 stimulation or IL-6 independent. This phenomenon raises the possibility that other growth factors may also be involved in the development of MM. Insulin like growth factor-I （IGF-I） plays an important role in the proliferation of a variety of cell types, in the development and growth of multiple tumors and in the prevention of apoptosis. IGF-I has recently been reported to play such a role in stimulating the MM cells growth, it even induces MM cells proliferation in IL-6 dependent cells, yet the detailed signaling components triggered by IGF-I have not been completely clarified. Thus, the present study are to address the signaling cascades triggered by IGF-I in MM cells.展开更多
Advances in molecular research in cancer have brought new therapeutic strategies into clinical usage.One new group of targets is tyrosine kinase receptors,which can be treated by several strategies,including small mol...Advances in molecular research in cancer have brought new therapeutic strategies into clinical usage.One new group of targets is tyrosine kinase receptors,which can be treated by several strategies,including small molecule tyrosine kinase inhibitors(TKIs) and monoclonal antibodies(mAbs).Aberrant activation of growth factors/receptors and their signal pathways are required for malignant transformation and progression in gastrointestinal(GI) carcinomas.The concept of targeting specif ic carcinogenic receptors has been validated by successful clinical application of many new drugs.Type I insulin-like growth factor(IGF) receptor(IGF-IR) signaling potently stimulates tumor progression and cellular differentiation,and is a promising new molecular target in human malignancies.In this review,we focus on this promising therapeutic target,IGF-IR.The IGF/IGF-IR axis is an important modifier of tumor cell proliferation,survival,growth,and treatment sensitivity in many malignant diseases,including human GI cancers.Preclinical studies demonstrated that downregulation of IGF-IR signals reversed the neoplastic phenotype and sensitized cells to anticancer treatments.These results were mainly obtained through our strategy of adenoviruses expressing dominant negative IGF-IR(IGF-IR/dn) against gastrointestinal cancers,including esophagus,stomach,colon,and pancreas.We also summarize a variety of strategies to interrupt the IGFs/IGF-IR axis and their preclinical experiences.Several mAbs and TKIs targeting IGF-IR have entered clinical trials,and early results have suggested that these agents have generally acceptable safety profiles as single agents.We summarize the advantages and disadvantages of each strategy and discuss the merits/demerits of dual targeting of IGF-IR and other growth factor receptors,including Her2 and the insulin receptor,as well as other alternatives and possible drug combinations.Thus,IGF-IR might be a candidate for a molecular therapeutic target in human GI carcinomas.展开更多
文摘Multiple myeloma is characterized by the accumulation of malignant plasma cells in thebone marrow. Significant progress in molecular mechanisms of signaling pathways underlying the survival and/or proliferation of these cells has been achieved. Interleukin 6 （IL-6） is an important cytokine leading to multiple myeloma （MM） cells growth and survival. However, some MM cells isolated from MM patients are poorly responsive to IL-6 stimulation or IL-6 independent. This phenomenon raises the possibility that other growth factors may also be involved in the development of MM. Insulin like growth factor-I （IGF-I） plays an important role in the proliferation of a variety of cell types, in the development and growth of multiple tumors and in the prevention of apoptosis. IGF-I has recently been reported to play such a role in stimulating the MM cells growth, it even induces MM cells proliferation in IL-6 dependent cells, yet the detailed signaling components triggered by IGF-I have not been completely clarified. Thus, the present study are to address the signaling cascades triggered by IGF-I in MM cells.
基金Supported by Grants-in-aid from the Ministry of Education,Culture,Sports,Science,and Technology the Ministry of Health,Labour and Welfare,Japan(in part)by Foundation for Promotion of Cancer Research in Japan
文摘Advances in molecular research in cancer have brought new therapeutic strategies into clinical usage.One new group of targets is tyrosine kinase receptors,which can be treated by several strategies,including small molecule tyrosine kinase inhibitors(TKIs) and monoclonal antibodies(mAbs).Aberrant activation of growth factors/receptors and their signal pathways are required for malignant transformation and progression in gastrointestinal(GI) carcinomas.The concept of targeting specif ic carcinogenic receptors has been validated by successful clinical application of many new drugs.Type I insulin-like growth factor(IGF) receptor(IGF-IR) signaling potently stimulates tumor progression and cellular differentiation,and is a promising new molecular target in human malignancies.In this review,we focus on this promising therapeutic target,IGF-IR.The IGF/IGF-IR axis is an important modifier of tumor cell proliferation,survival,growth,and treatment sensitivity in many malignant diseases,including human GI cancers.Preclinical studies demonstrated that downregulation of IGF-IR signals reversed the neoplastic phenotype and sensitized cells to anticancer treatments.These results were mainly obtained through our strategy of adenoviruses expressing dominant negative IGF-IR(IGF-IR/dn) against gastrointestinal cancers,including esophagus,stomach,colon,and pancreas.We also summarize a variety of strategies to interrupt the IGFs/IGF-IR axis and their preclinical experiences.Several mAbs and TKIs targeting IGF-IR have entered clinical trials,and early results have suggested that these agents have generally acceptable safety profiles as single agents.We summarize the advantages and disadvantages of each strategy and discuss the merits/demerits of dual targeting of IGF-IR and other growth factor receptors,including Her2 and the insulin receptor,as well as other alternatives and possible drug combinations.Thus,IGF-IR might be a candidate for a molecular therapeutic target in human GI carcinomas.
