title: CCR9-CCL25 interactions promote cisplatin resistance in breast cancer cell through Akt activation in a PI3K-dependent and FAK-independent fashion.
abstract: BACKGROUND
  Chemotherapy heavily relies on apoptosis to kill breast cancer (BrCa) cells. Many breast tumors respond to chemotherapy, but cells that survive this initial response gain resistance to subsequent treatments. This leads to aggressive cell variants with an enhanced ability to migrate, invade and survive at secondary sites. Metastasis and chemoresistance are responsible for most cancer-related deaths; hence, therapies designed to minimize both are greatly needed. We have recently shown that CCR9-CCL25 interactions promote BrCa cell migration and invasion, while others have shown that this axis play important role in T cell survival. In this study we have shown potential role of CCR9-CCL25 axis in breast cancer cell survival and therapeutic efficacy of cisplatin.
  
  
  METHODS
  Bromodeoxyuridine (BrdU) incorporation, Vybrant apoptosis and TUNEL assays were performed to ascertain the role of CCR9-CCL25 axis in cisplatin-induced apoptosis of BrCa cells. Fast Activated Cell-based ELISA (FACE) assay was used to quantify In situ activation of PI3Kp85, AktSer473, GSK-3βSer9 and FKHRThr24 in breast cancer cells with or without cisplatin treatment in presence or absence of CCL25.
  
  
  RESULTS
  CCR9-CCL25 axis provides survival advantage to BrCa cells and inhibits cisplatin-induced apoptosis in a PI3K-dependent and focal adhesion kinase (FAK)-independent fashion. Furthermore, CCR9-CCL25 axis activates cell-survival signals through Akt and subsequent glycogen synthase kinase-3 beta (GSK-3β) and forkhead in human rhabdomyosarcoma (FKHR) inactivation. These results show that CCR9-CCL25 axis play important role in BrCa cell survival and low chemotherapeutic efficacy of cisplatin primarily through PI3K/Akt dependent fashion.
authors.affiliation: Department of Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, 720 Westview Drive SW, Atlanta, GA 30310 USA.
authors.forename: Crystal
authors.initials: C
authors.lastname: Johnson-Holiday
authors.forename: Rajesh
authors.initials: R
authors.lastname: Singh
authors.forename: Erica L
authors.initials: EL
authors.lastname: Johnson
authors.forename: William E
authors.initials: WE
authors.lastname: Grizzle
authors.forename: James W
authors.initials: JW
authors.lastname: Lillard
authors.forename: Shailesh
authors.initials: S
authors.lastname: Singh
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis; D001943:Breast Neoplasms; D002465:Cell Movement; D002470:Cell Survival; D019742:Chemokines, CC / Q000378:metabolism*; D002945:Cisplatin / Q000494:pharmacology*; D019008:Drug Resistance, Neoplasm / Q000502:physiology*; D051417:Focal Adhesion Kinase 1 / Q000378:metabolism; D006801:Humans; D009361:Neoplasm Invasiveness; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D054388:Receptors, CCR / Q000378:metabolism*; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; C119309:CC chemokine receptor 9; C108074:CCL25 protein, human; D019742:Chemokines, CC; D054388:Receptors, CCR; D019869:Phosphatidylinositol 3-Kinases; D051417:Focal Adhesion Kinase 1; C496050:PTK2 protein, human; D051057:Proto-Oncogene Proteins c-akt; D002945:Cisplatin