Vesnarinone downregulates CXCR4 expression via upregulation of Krüppel-like factor 2 in oral cancer cells.
BACKGROUND
We have demonstrated that the stromal cell-derived factor-1 (SDF-1; CXCL12)/CXCR4 system is involved in the establishment of lymph node metastasis in oral squamous cell carcinoma (SCC). Chemotherapy is a powerful tool for the treatment of oral cancer, including oral SCC; however, the effects of chemotherapeutic agents on the expression of CXCR4 are unknown. In this study, we examined the expression of CXCR4 associated with the chemotherapeutic agents in oral cancer cells.


RESULTS
The expression of CXCR4 was examined using 3 different chemotherapeutic agents; 5-fluorouracil, cisplatin, and vesnarinone (3,4-dihydro-6-[4-(3,4-dimethoxybenzoyl)-1-piperazinyl]-2-(1H)-quinolinone) in B88, a line of oral cancer cells that exhibits high levels of CXCR4 and lymph node metastatic potential. Of the 3 chemotherapeutic agents that we examined, only vesnarinone downregulated the expression of CXCR4 at the mRNA as well as the protein level. Vesnarinone significantly inhibited lymph node metastasis in tumor-bearing nude mice. Moreover, vesnarinone markedly inhibited 2.7-kb human CXCR4 promoter activity, and we identified the transcription factor, Krüppel-like factor 2 (KLF2), as a novel vesnarinone-responsive molecule, which was bound to the CXCR4 promoter at positions -300 to -167 relative to the transcription start site. The forced-expression of KLF2 led to the downregulation of CXCR4 mRNA and impaired CXCR4 promoter activity. The use of siRNA against KLF2 led to an upregulation of CXCR4 mRNA.


CONCLUSIONS
These Results indicate that vesnarinone downregulates CXCR4 via the upregulation of KLF2 in oral cancer.
Uchida
Daisuke
D
Department of Oral Surgery, Division of Integrated Sciences of Translational Research, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan. daisuke@dent.tokushima-u.ac.jp
Onoue
Tomitaro
T
Begum
Nasima-Mila
NM
Kuribayashi
Nobuyuki
N
Tomizuka
Yoshifumi
Y
Tamatani
Tetsuya
T
Nagai
Hirokazu
H
Miyamoto
Youji
Y
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects; D002945:Cisplatin / Q000494:pharmacology; D015536:Down-Regulation / Q000187:drug effects; D005434:Flow Cytometry; D005472:Fluorouracil / Q000494:pharmacology; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006367:HeLa Cells; D006801:Humans; D051741:Kruppel-Like Transcription Factors / Q000235:genetics* / Q000378:metabolism; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009062:Mouth Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D020411:Oligonucleotide Array Sequence Analysis; D011401:Promoter Regions, Genetic / Q000235:genetics; D011719:Pyrazines; D011804:Quinolines / Q000494:pharmacology*; D034622:RNA Interference; D019718:Receptors, CXCR4 / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D047368:Tumor Burden / Q000235:genetics; D023041:Xenograft Model Antitumor Assays
D000970:Antineoplastic Agents; C527276:CXCR4 protein, human; C096161:KLF2 protein, human; D051741:Kruppel-Like Transcription Factors; D011719:Pyrazines; D011804:Quinolines; D019718:Receptors, CXCR4; C041667:vesnarinone; D008156:Luciferases; D002945:Cisplatin; D005472:Fluorouracil