Regulation of inflammation by the NF-κB pathway in ovarian cancer stem cells.
OBJECTIVE
The NFκB pathway is a major source of pro-inflammatory cytokines, which may contribute to cancer chemoresistance. We showed that constitutive NFκB activity is characteristic of the ovarian cancer stem cells (OCSCs). The aim of this study is to determine whether the inhibition of NFκB by Eriocalyxin B (EriB) in the OCSCs may induce cell death in otherwise chemoresistant cells.


METHODS
OCSCs and mature ovarian cancer cells (mOCCs) were treated with increasing concentrations of EriB. Cell viability was measured using the Celltiter 96 assay, and caspase activity was quantified using Caspase-Glo™ assay. Cytokine levels were quantified using xMAP technology.


RESULTS
EriB decreased the percent of viable cells in all cultures tested with GI(50) of 0.5-1 μm after 48 hrs of treatment. The intracellular changes associated with EriB-induced cell death are: (i) inhibition of NF-κB activity; (ii) decreased cytokine production; (iii) activation of caspases; and (iv) down-regulation of XIAP. In addition, EriB is able to sensitize OCSCs to TNFα and FasL-mediated cell death.


CONCLUSIONS
Inhibition of the NFκB pathway induces cell death in the OCSCs. Because the OCSCs may represent the source of recurrence and chemoresistance, the use of NFκB inhibitors like EriB may prevent recurrence in patients with ovarian cancer.
Leizer
Aliza L
AL
Department of Obstetrics Gynecology and Reproductive Sciences, Yale University, New Haven, CT 06520, USA.
Alvero
Ayesha B
AB
Fu
Han Hsuan
HH
Holmberg
Jennie C
JC
Cheng
Yung-Chi
YC
Silasi
Dan-Arin
DA
Rutherford
Thomas
T
Mor
Gil
G
D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D020169:Caspases / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D016207:Cytokines / Q000096:biosynthesis; D004224:Diterpenes / Q000494:pharmacology*; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006801:Humans; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000378:metabolism*; D014411:Neoplastic Stem Cells / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism*; D010051:Ovarian Neoplasms / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors; D051636:X-Linked Inhibitor of Apoptosis Protein / Q000235:genetics
D016207:Cytokines; D004224:Diterpenes; D016328:NF-kappa B; D014409:Tumor Necrosis Factor-alpha; D051636:X-Linked Inhibitor of Apoptosis Protein; C496866:XIAP protein, human; C516552:eriocalyxin B; D020169:Caspases
N Engl J Med. 2009 Jul 9;361(2):170-7
19587342
Oncogene. 2008 Jan 7;27(2):225-33
18176604
Cell Death Differ. 2007 Feb;14(2):306-17
16778832
Cancer Biol Ther. 2009 Sep;8(18):1747-53
19738422
CA Cancer J Clin. 2009 Jul-Aug;59(4):225-49
19474385
N Engl J Med. 1986 Dec 25;315(26):1650-9
3537791
Cancer Res. 2009 Mar 1;69(5):1782-91
19223549
Cancer Res. 2006 Apr 1;66(7):3859-68
16585214
Cancer Cell. 2004 Sep;6(3):203-8
15380510
Oncol Res. 2004;14(11-12):567-78
15666998
Nat Med. 1999 Apr;5(4):412-7
10202930
Mol Hum Reprod. 2004 Jan;10(1):33-41
14665704
Nature. 2001 Nov 1;414(6859):105-11
11689955
J Soc Gynecol Investig. 2006 Feb;13(2):145-52
16443509
Nat Rev Cancer. 2004 Jan;4(1):71-8
14708027
J Cell Sci. 2004 Jul 15;117(Pt 16):3615-24
15252129
Gene Ther. 2008 May;15(10):730-8
18401438
Novartis Found Symp. 2004;256:158-68; discussion 168-72, 259-69
15027489
Cancer. 2006 Feb 1;106(3):599-608
16388521
N Engl J Med. 2006 Sep 21;355(12):1253-61
16990388
J Soc Gynecol Investig. 2004 May;11(4):252-9
15120700
PLoS One. 2009 Aug 10;4(8):e6562
19668347
J Immunol. 2010 Jul 15;185(2):1248-57
20554966
Drug Resist Updat. 2002 Jul-Aug;5(3-4):131-46
12237081
Clin Cancer Res. 2003 Jul;9(7):2826-36
12855663
Cancer Biol Ther. 2004 Dec;3(12):1214-6
15611628
Nat Rev Cancer. 2008 Oct;8(10):755-68
18784658
Cell. 2006 Mar 24;124(6):1111-5
16564000
Am J Reprod Immunol. 2007 Feb;57(2):93-107
17217363
Cancer Treat Res. 2002;107:99-118
11775463
J Immunol. 2003 Jun 1;170(11):5630-5
12759443
Oncogene. 2003 May 1;22(17):2611-20
12730675
Oncogene. 2008 Aug 7;27(34):4712-23
18408758
Nature. 2002 Dec 19-26;420(6917):860-7
12490959
Apoptosis. 2001 Aug;6(4):253-61
11445667
Cancer. 2009 Jul 15;115(14):3204-16
19472400
Cell Cycle. 2009 Jan 1;8(1):158-66
19158483
Stem Cells. 2009 Oct;27(10):2405-13
19658191
J Biol Chem. 2003 Sep 26;278(39):37297-305
12867425
Nature. 2004 Sep 23;431(7007):461-6
15329734
Int J Oncol. 2003 Oct;23(4):1187-93
12964003
J Clin Immunol. 2005 Nov;25(6):541-50
16380818
Oncogene. 2010 Jun 17;29(24):3545-53
20400975