title: Dimethyl Fumarate Inhibits the Nuclear Factor κB Pathway in Breast Cancer Cells by Covalent Modification of p65 Protein.
abstract: In breast tumors, activation of the nuclear factor κB (NFκB) pathway promotes survival, migration, invasion, angiogenesis, stem cell-like properties, and resistance to therapy--all phenotypes of aggressive disease where therapy options remain limited. Adding an anti-inflammatory/anti-NFκB agent to breast cancer treatment would be beneficial, but no such drug is approved as either a monotherapy or adjuvant therapy. To address this need, we examined whether dimethyl fumarate (DMF), an anti-inflammatory drug already in clinical use for multiple sclerosis, can inhibit the NFκB pathway. We found that DMF effectively blocks NFκB activity in multiple breast cancer cell lines and abrogates NFκB-dependent mammosphere formation, indicating that DMF has anti-cancer stem cell properties. In addition, DMF inhibits cell proliferation and significantly impairs xenograft tumor growth. Mechanistically, DMF prevents p65 nuclear translocation and attenuates its DNA binding activity but has no effect on upstream proteins in the NFκB pathway. Dimethyl succinate, the inactive analog of DMF that lacks the electrophilic double bond of fumarate, is unable to inhibit NFκB activity. Also, the cell-permeable thiol N-acetyl l-cysteine, reverses DMF inhibition of the NFκB pathway, supporting the notion that the electrophile, DMF, acts via covalent modification. To determine whether DMF interacts directly with p65, we synthesized and used a novel chemical probe of DMF by incorporating an alkyne functionality and found that DMF covalently modifies p65, with cysteine 38 being essential for the activity of DMF. These results establish DMF as an NFκB inhibitor with anti-tumor activity that may add therapeutic value in the treatment of aggressive breast cancers.
authors.affiliation: From the Departments of Physiology and Biophysics and ikastr2@uic.edu.
authors.forename: Irida
authors.initials: I
authors.lastname: Kastrati
authors.affiliation: Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago, Illinois 60612.
authors.forename: Marton I
authors.initials: MI
authors.lastname: Siklos
authors.affiliation: From the Departments of Physiology and Biophysics and.
authors.forename: Esther L
authors.initials: EL
authors.lastname: Calderon-Gierszal
authors.affiliation: From the Departments of Physiology and Biophysics and.
authors.forename: Lamiaa
authors.initials: L
authors.lastname: El-Shennawy
authors.affiliation: From the Departments of Physiology and Biophysics and.
authors.forename: Gergana
authors.initials: G
authors.lastname: Georgieva
authors.affiliation: Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago, Illinois 60612.
authors.forename: Emily N
authors.initials: EN
authors.lastname: Thayer
authors.affiliation: Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago, Illinois 60612.
authors.forename: Gregory R J
authors.initials: GR
authors.lastname: Thatcher
authors.affiliation: From the Departments of Physiology and Biophysics and.
authors.forename: Jonna
authors.initials: J
authors.lastname: Frasor
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000187:drug effects; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D003545:Cysteine / Q000737:chemistry; D000069462:Dimethyl Fumarate / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D017930:Genes, Reporter / Q000187:drug effects; D006801:Humans; D008819:Mice, Nude; D016328:NF-kappa B / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D014411:Neoplastic Stem Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D011897:Random Allocation; D015398:Signal Transduction / Q000187:drug effects*; D051996:Transcription Factor RelA / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D047368:Tumor Burden / Q000187:drug effects; D023041:Xenograft Model Antitumor Assays
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D000970:Antineoplastic Agents; D016328:NF-kappa B; D009363:Neoplasm Proteins; C498143:RELA protein, human; D051996:Transcription Factor RelA; D000069462:Dimethyl Fumarate; D003545:Cysteine
keywords: NFκB; breast cancer; chemical modification; covalent modification; cysteine; dimethyl fumarate; drug action; inflammation; inhibitor; mammosphere