Targeting NF-κB in infantile hemangioma-derived stem cells reduces VEGF-A expression.
BACKGROUND
infantile hemangioma (IH) is a most common tumor of infancy. Using infantile hemangioma-derived stem cells (HemSCs), we recently demonstrated that corticosteroids suppress the expression of VEGF-A, monocyte chemoattractant protein-1 (MCP-1), urokinase plasminogen activator receptor (uPAR), and interleukin-6 (IL-6); each of these are known targets of the transcription factor nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB). In the present study, we examined the expression of these NF-κB target genes in IH tissue specimens and the effect of NF-κB regulation on the expression of pro-angiogenic cytokines, and in particular VEGF-A, in HemSCs.


METHODS
RNA extracted from IH tissue and hemangioma-derived stem cells (HemSCs) was used to analyze NF-κB target gene expression by reverse transcription-quantitative PCR (RT-qPCR). The effects of NF-κB blockade were examined in HemSCs. Immunostaining, immunoblotting and ELISA were used to assess protein expression.


RESULTS
MCP-1, uPAR, and IL-6 were found to be differentially expressed in proliferating versus involuting IH. Corticosteroids suppressed NF-κB activity of HemSCs. Velcade (Bortezomib), a proteosome inhibitor that can indirectly inhibit NF-κB, impaired HemSCs viability and expression of pro-angiogenic factors. Furthermore, specific inhibition of NF-κB resulted in suppression of VEGF-A.


CONCLUSIONS
we demonstrate expression of NF-κB target genes in proliferating IH. In addition, we show that the expression of several pro-angiogenic factors in HemSCs, and in particular VEGF-A, is regulated by NF-B activity.
Greenberger
Shoshana
S
Department of Surgery, Children's Hospital Boston and Harvard Medical School, Boston, MA 02115, USA.
Adini
Irit
I
Boscolo
Elisa
E
Mulliken
John B
JB
Bischoff
Joyce
J
D000970:Antineoplastic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001897:Boronic Acids / Q000494:pharmacology; D000069286:Bortezomib; D049109:Cell Proliferation / Q000187:drug effects; D002648:Child; D002675:Child, Preschool; D003907:Dexamethasone / Q000494:pharmacology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D018324:Hemangioma, Capillary / Q000151:congenital / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D058990:Molecular Targeted Therapy / Q000379:methods; D016328:NF-kappa B / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D014411:Neoplastic Stem Cells / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D009386:Neoplastic Syndromes, Hereditary; D011719:Pyrazines / Q000494:pharmacology; D012878:Skin Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics* / Q000378:metabolism
D000970:Antineoplastic Agents; D001897:Boronic Acids; D016328:NF-kappa B; D011719:Pyrazines; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D000069286:Bortezomib; D003907:Dexamethasone