Curcumin Prevents Palmitoylation of Integrin β4 in Breast Cancer Cells.
Curcumin has been shown to mitigate cancer phenotypes such as invasive migration, proliferation, and survival by disrupting numerous signaling pathways. Our previous studies showed that curcumin inhibits integrin β4 (ITG β4)-dependent migration by blocking interaction of this integrin with growth factor receptors in lipid rafts. In the current study, we investigated the possibility that curcumin inhibits ITG β4 palmitoylation, a post-translational modification required for its lipid raft localization and signaling activity. We found that the levels of ITG β4 palmitoylation correlated with the invasive potential of breast cancer cells, and that curcumin effectively reduced the levels of ITG β4 palmitoylation in invasive breast cancer cells. Through studies of ITG β4 palmitoylation kinetics, we concluded curcumin suppressed palmitoylation independent of growth factor-induced phosphorylation of key ITG β4 Ser and Tyr residues. Rather, curcumin blocked autoacylation of the palmitoyl acyltransferase DHHC3 that is responsible for ITG β4 palmitoylation. Moreover, these data reveal that curcumin is able to prevent the palmitoylation of a subset of proteins, but not indiscriminately bind to and block all cysteines from modifications. Our studies reveal a novel paradigm for curcumin to account for much of its biological activity, and specifically, how it is able to suppress the signaling function of ITG β4 in breast cancer cells.
Department of Microbiology and FeistWeiller Cancer Center, Louisiana State University Health Sciences Center, Shreveport, Louisiana, United States of America.
David T
DT
Coleman
Department of Physiology and Stephenson Cancer Center, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America; Department of Microbiology and FeistWeiller Cancer Center, Louisiana State University Health Sciences Center, Shreveport, Louisiana, United States of America.
Young Hwa
YH
Soung
College of Pharmacy, Seoul National University, Seoul, South Korea.
Young-Joon
YJ
Surh
Department of Microbiology and FeistWeiller Cancer Center, Louisiana State University Health Sciences Center, Shreveport, Louisiana, United States of America.
James A
JA
Cardelli
Department of Physiology and Stephenson Cancer Center, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America; Department of Microbiology and FeistWeiller Cancer Center, Louisiana State University Health Sciences Center, Shreveport, Louisiana, United States of America.
Jun
J
Chung
D000215:Acylation; D000217:Acyltransferases / Q000378:metabolism; D000970:Antineoplastic Agents / Q000494:pharmacology*; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism*; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects / Q000235:genetics; D003474:Curcumin / Q000494:pharmacology*; D005260:Female; D006801:Humans; D039663:Integrin beta4 / Q000235:genetics / Q000378:metabolism*; D054878:Lipoylation / Q000187:drug effects*; D010766:Phosphorylation; D015398:Signal Transduction / Q000187:drug effects
D000970:Antineoplastic Agents; D039663:Integrin beta4; D000217:Acyltransferases; C574550:ZDHHC3 protein, human; D003474:Curcumin