Induction of E-cadherin in lung cancer and interaction with growth suppression by histone deacetylase inhibition.
BACKGROUND
Loss of E-cadherin confers a poor prognosis in lung cancer patients and is associated with in vitro resistance to endothelial growth factor receptor inhibitors. Zinc finger E box-binding homeobox (ZEB)-1, the predominant transcriptional suppressor of E-cadherin in lung tumor lines, recruits histone deacetylases (HDACs) as co-repressors.


METHODS
NSCLC cell lines were treated with HDAC inhibitors and analyzed for E-cadherin induction, growth inhibition and apoptosis. National Cancer Institute-H157 cells expressing ectopic E-cadherin were tested for tumorigenicity in murine xenografts.


RESULTS
We found that treatment with MS-275, compared to vorinostat (SAHA), valproic acid or trichostatin A, was most effective in E-cadherin up-regulation and persistence in non-small cell lung cancers. As with other tumor types and HDAC inhibitors, MS-275 inhibited growth and induced apoptosis. Importantly, blocking E-cadherin induction by short hairpin RNA resulted in less inhibition by MS-275, implicating the epithelial to mesenchymal phenotype process as a contributing factor. In contrast to H460 and H661, H157 cells were resistant to E-cadherin up-regulation by HDAC inhibitors. However, E-cadherin was restored, in a synergistic manner, by combined knockdown of ZEB-1 and ZEB-2. In addition, H157 cells stably transfected with E-cadherin were markedly attenuated in their tumor forming ability. Lastly, combining MS-275 with the microtubule stabilizing agent, paclitaxel, or 17-(allylamino)-17-demethoxygeldanamycin, a heat shock protein 90 inhibitor, resulted in synergistic growth inhibition. Since MS-275 has no reported activity against HDAC6, which regulates both microtubule and heat shock protein 90 functions, other mechanisms of synergy are anticipated.


CONCLUSIONS
These results support the role of ZEB proteins and HDAC inhibitors in the pathogenesis and treatment of lung cancer.
Kakihana
Masatoshi
M
Division of Medical Oncology, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado, USA.
Ohira
Tatsuo
T
Chan
Daniel
D
Webster
Robin B
RB
Kato
Harubumi
H
Drabkin
Harry A
HA
Gemmill
Robert M
RM
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D001549:Benzamides / Q000494:pharmacology; D016227:Benzoquinones / Q000494:pharmacology; D015153:Blotting, Western; D015820:Cadherins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D002289:Carcinoma, Non-Small-Cell Lung / Q000378:metabolism* / Q000473:pathology / Q000517:prevention & control; D049109:Cell Proliferation / Q000187:drug effects; D005260:Female; D005434:Flow Cytometry; D018841:HSP90 Heat-Shock Proteins / Q000037:antagonists & inhibitors; D056572:Histone Deacetylase Inhibitors / Q000494:pharmacology; D006655:Histone Deacetylases / Q000737:chemistry / Q000378:metabolism; D018398:Homeodomain Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D006801:Humans; D006877:Hydroxamic Acids / Q000494:pharmacology; D047029:Lactams, Macrocyclic / Q000494:pharmacology; D008175:Lung Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000517:prevention & control; D011725:Pyridines / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000494:pharmacology; D051381:Rats; D011923:Rats, Nude; D012097:Repressor Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014157:Transcription Factors / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D014407:Tumor Cells, Cultured; D015854:Up-Regulation; D000077337:Vorinostat; D000074165:Zinc Finger E-box Binding Homeobox 2; D000071799:Zinc Finger E-box-Binding Homeobox 1
D000970:Antineoplastic Agents; D001549:Benzamides; D016227:Benzoquinones; D015820:Cadherins; D018841:HSP90 Heat-Shock Proteins; D056572:Histone Deacetylase Inhibitors; D018398:Homeodomain Proteins; D006877:Hydroxamic Acids; D047029:Lactams, Macrocyclic; D011725:Pyridines; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D012097:Repressor Proteins; D014157:Transcription Factors; C486307:ZEB1 protein, human; C492363:ZEB2 protein, human; D000074165:Zinc Finger E-box Binding Homeobox 2; D000071799:Zinc Finger E-box-Binding Homeobox 1; C118739:entinostat; C012589:trichostatin A; C112765:tanespimycin; D000077337:Vorinostat; D006655:Histone Deacetylases