RESUMO
Histidine decarboxylase (HDC) is expressed by the cells of melanoma, in which the histamine content tends to be relatively high. This study shows that elevated expression of HDC was found by western blot analysis of primary and metastatic melanoma tissue using a polyclonal HDC specific antibody. The specificity of anti-HDC antibody was confirmed by inhibition of HDC translation (i.e., immunopositivity) in melanoma cells by HDC-specific antisense oligonucleotide. Moreover, the decrease in proliferation caused by HDC antisense oligonucleotides indicates considerable functional relevance of histamine synthesis in melanoma growth and suggests a possible in situ application of specific antisense oligonucleotides for HDC in melanoma therapy.
Assuntos
Histidina Descarboxilase/genética , Melanoma/patologia , Oligonucleotídeos Antissenso/farmacologia , Neoplasias Cutâneas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Divisão Celular/genética , Feminino , Terapia Genética , Humanos , Técnicas In Vitro , Masculino , Melanoma/metabolismo , Melanoma/terapia , Pessoa de Meia-Idade , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/terapia , Células Tumorais Cultivadas/citologia , Células Tumorais Cultivadas/enzimologiaRESUMO
Based on cDNA sequence data epsilon chain-specific antisense oligonucleotides were synthesized and checked on in vitro IgE production. Using peripheral blood cells from a hypereosinophilic patient and a human IgE myeloma cell line, U266, marked reduction of in vitro IgE production measured by PRIST was observed. The effect of epsilon antisenses proved to be isotype specific since IgG production by both peripheral blood cells and a lymphoma cell line, CESS, was not affected. Moreover, the expression of other markers on U266 (interleukin-6 receptor and gp130) were not influenced by epsilon-specific antisense oligonucleotides.
Assuntos
Síndrome Hipereosinofílica/imunologia , Imunoglobulina E/efeitos dos fármacos , Cadeias épsilon de Imunoglobulina/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Oligonucleotídeos Antissenso/farmacologia , Plasmocitoma/imunologia , Humanos , Síndrome Hipereosinofílica/sangue , Imunoglobulina E/biossíntese , Leucócitos Mononucleares/metabolismo , Células Tumorais CultivadasRESUMO
The biosynthesis of interleukin-6 receptor (IL-6R) and gp130 in vitro was blocked using specific antisense oligonucleotides (ASO) in HepG2 liver cells and the efficacy of various ASOs was tested on the generation of IL-6-induced junB mRNA. We used three ASOs specific for the IL-6 receptor, three specific for gp130 and a control (nonsense) oligonucleotide specific for epsilon-chain of IgE (not expressing in HepG2 cells). Our data indicate that a gp130-specific ASO, g2, was the most effective blocker of IL-6-induced junB mRNA, whilst the IL-6 receptor ASOs alone were ineffective. The mechanism of gene inactivation by ASO treatment was partially elucidated by demonstration of the loss of gp130 mRNA from cells treated with ASOs showing functional efficacy. Our data may help to design antisense oligonucleotides that are effective in therapy (e.g. as anti-inflammatory agents) in the future.
Assuntos
Antígenos CD/genética , Carcinoma Hepatocelular/patologia , Interleucina-6/farmacologia , Glicoproteínas de Membrana/genética , Oligodesoxirribonucleotídeos Antissenso/farmacologia , Proteínas Proto-Oncogênicas c-jun/genética , RNA Mensageiro/efeitos dos fármacos , Carcinoma Hepatocelular/genética , Receptor gp130 de Citocina , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Oligodesoxirribonucleotídeos Antissenso/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Interleucina-6/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Transcrição Gênica , Células Tumorais CultivadasRESUMO
Histamine is produced from histidine by histidine decarboxylase (HDC) in many cells including normal and malignant lymphocytes. We examined the expression of HDC and the effect of histamine receptor antagonists on the proliferation of a human T cell line, Jurkat and on antigen-driven proliferation of lymphocytes from ovalbumin-immunized mice. Our results demonstrate that HDC is inducible in Jurkat cells by anti-CD3. The H1 receptor antagonist triprolidine dose dependently inhibits proliferation of both Jurkat cells and ovalbumin-stimulated murine lymphocytes, while the H2 antagonist ranitidine was ineffective. Alpha-fluoro-methyl-histidine blocking HDC activity did not inhibit the T cell proliferation, suggesting an existing pool of histamine in T cells.