Studies of Downstream Effectors of AKT in Multiple Myeloma Cell Line

• Main Authors: Lee-Ping Yew, 尤麗萍
• Other Authors: Jung-Hsin Hsu
• Format: Others
• Language: en_US
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/76668040556609843694

碩士 === 國立東華大學 === 生物技術研究所 === 95 === Multiple myeloma (MM) is a plasma cell malignancy that accumulates within the bone marrow. Interleukin-6 (IL-6) is involved in the maintenance and progression of several diseases such as multiple myeloma, rheumatoid arthritis, or osteoporosis. IL-6 is an important tumor growth factor for multiple myeloma cells. IL-6 activates the phosphatidylinositol 3-kinase (PI3-K)/Akt kinase pathway in myeloma cells. Besides, IL-6 also activates JAK-STAT and RAS-MEK-ERK pathways. Thus, IL-6 plays an important role in promoting proliferation, protecting survival and stimulating migration of myeloma cells. A disturbed balance between cell proliferation and programmed cell death would cause carcinogenesis process. PI3-K/Akt signaling pathways are frequently disturbed in many human cancers. Recent evidence indicates that Akt mediates many of the downstream events controlled by PI3-kinase. MM cell line AF-10 cells were treated with IL-6 to activate Akt, and the Akt substrate proteins were isolated by immunoprecipitation. Akt kinase specifically phosphorylates its substrates at the (R/K)X(R/K)XX(S/T) motif, where X is any amino acid. Those immunoprecipitated molecules were associated with an antibody against the phospho-form of this motif. The immunoprecipitated protein molecules were then analyzed by one-dimensional gel electrophoresis, followed by mass spectrometry. Putative Akt substrates including myosin-9 (nonmuscle IIa), zinc finger protein 195, zinc finger protein 155, vimentin, β-tubulin, and β-actin have been identified. We have tried to identify vimentin, β-tubulin, and β-actin with specific antibodies.