title: Identification of ADAM10 as a major source of HER2 ectodomain sheddase activity in HER2 overexpressing breast cancer cells.
abstract: Overexpression and activating mutations of ErbB family members have been implicated in the development and progression of a variety of tumor types. Cleavage of the HER2 receptor by an as yet unidentified ectodomain sheddase has been shown to liberate the HER2 extracellular domain (ECD) leaving a fragment with constitutive kinase activity that can provide ligand-independent growth and survival signals to the cell. This process is clinically relevant since HER2 ECD serum levels in metastatic breast cancer patients are associated with a poorer prognosis. Thus, inhibition of the HER2 sheddase may provide a novel therapeutic approach for breast cancer. We describe the use of transcriptional profiling, pharmacological and in vitro approaches to identify the major source of HER2 sheddase activity. Real-time PCR was used to identify those ADAM family members which were expressed in HER2 shedding cell lines. siRNAs that selectively inhibited ADAM10 expression reduced HER2 shedding. In addition, we profiled over 1000 small molecules for in vitro inhibition of a panel of ADAM and MMP proteins; a positive correlation was observed only between ADAM10 inhibition and reduction of HER2 ECD shedding in a cell based assay. Finally, in vitro studies demonstrate that in combination with low doses of Herceptin, selective ADAM10 inhibitors decrease proliferation in HER2 overexpressing cell lines while inhibitors, that do not inhibit ADAM10, have no impact. These results are consistent with ADAM10 being a major determinant of HER2 shedding, the inhibition of which, may provide a novel therapeutic approach for treating a variety of cancers with active HER2 signaling.
authors.affiliation: Drug Discovery, Incyte Corporation, Experimental Station, Wilmington, Delaware 19880, USA.
authors.forename: Phillip C C
authors.initials: PC
authors.lastname: Liu
authors.forename: Xiangdong
authors.initials: X
authors.lastname: Liu
authors.forename: Yanlong
authors.initials: Y
authors.lastname: Li
authors.forename: Maryanne
authors.initials: M
authors.lastname: Covington
authors.forename: Richard
authors.initials: R
authors.lastname: Wynn
authors.forename: Reid
authors.initials: R
authors.lastname: Huber
authors.forename: Milton
authors.initials: M
authors.lastname: Hillman
authors.forename: Gengjie
authors.initials: G
authors.lastname: Yang
authors.forename: Dawn
authors.initials: D
authors.lastname: Ellis
authors.forename: Cindy
authors.initials: C
authors.lastname: Marando
authors.forename: Kamna
authors.initials: K
authors.lastname: Katiyar
authors.forename: Jodi
authors.initials: J
authors.lastname: Bradley
authors.forename: Kenneth
authors.initials: K
authors.lastname: Abremski
authors.forename: Mark
authors.initials: M
authors.lastname: Stow
authors.forename: Mark
authors.initials: M
authors.lastname: Rupar
authors.forename: Jincong
authors.initials: J
authors.lastname: Zhuo
authors.forename: Yun-Long
authors.initials: YL
authors.lastname: Li
authors.forename: Qiyan
authors.initials: Q
authors.lastname: Lin
authors.forename: David
authors.initials: D
authors.lastname: Burns
authors.forename: Meizhong
authors.initials: M
authors.lastname: Xu
authors.forename: Colin
authors.initials: C
authors.lastname: Zhang
authors.forename: Ding-Quan
authors.initials: DQ
authors.lastname: Qian
authors.forename: Chunhong
authors.initials: C
authors.lastname: He
authors.forename: Vaqar
authors.initials: V
authors.lastname: Sharief
authors.forename: Lingkai
authors.initials: L
authors.lastname: Weng
authors.forename: Costas
authors.initials: C
authors.lastname: Agrios
authors.forename: Eric
authors.initials: E
authors.lastname: Shi
authors.forename: Brian
authors.initials: B
authors.lastname: Metcalf
authors.forename: Robert
authors.initials: R
authors.lastname: Newton
authors.forename: Steven
authors.initials: S
authors.lastname: Friedman
authors.forename: Wenqing
authors.initials: W
authors.lastname: Yao
authors.forename: Peggy
authors.initials: P
authors.lastname: Scherle
authors.forename: Gregory
authors.initials: G
authors.lastname: Hollis
authors.forename: Timothy C
authors.initials: TC
authors.lastname: Burn
mesh_terms: D051722:ADAM Proteins / Q000378:metabolism*; D000072197:ADAM10 Protein; D053829:Amyloid Precursor Protein Secretases / Q000378:metabolism*; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents / Q000494:pharmacology; D001483:Base Sequence; D001943:Breast Neoplasms / Q000201:enzymology / Q000235:genetics* / Q000473:pathology; D045744:Cell Line, Tumor; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D034741:RNA, Small Interfering / Q000235:genetics; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D000068878:Trastuzumab
chemical_list: D051722:ADAM Proteins; D000072197:ADAM10 Protein; D053829:Amyloid Precursor Protein Secretases; D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D008565:Membrane Proteins; D034741:RNA, Small Interfering; D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab; C491236:ADAM10 protein, human