RESUMO
LIGHT (HVEM-L, TNFSF14, or CD258), an entity homologous to lymphotoxins, with inducible nature and the ability to compete with herpes simplex virus glycoprotein D for herpes virus entry mediator (HVEM)/tumor necrosis factor (TNF)-related 2, is a member of the TNF superfamily. It is expressed as a homotrimer on activated T cells and dendritic cells (DCs), and has three receptors: HVEM, LT-ß receptor (LTßR), and decoy receptor 3 (DcR3). So far, three receptors with distinct cellular expression patterns are known to interact with LIGHT. Follicular DCs and stromal cells bind LIGHT through LTßR. We monitored the effects of LIGHT on human bone marrow-derived mesenchymal stem cells (BM-MSCs). At first, we checked the negative and positive differentiation markers of BM-MSCs. And we confirmed the quality of MSCs by staining cells undergoing adipogenesis (Oil Red O staining), chondrogenesis (Alcian blue staining), and osteogenesis (Alizarin red staining). After rhLIGHT treatment, we monitored the count, viability, and proliferation of cells and cell cycle distribution. PDGF and TGFß production by rhLIGHT was examined by ELISA, and the underlying biological mechanisms were studied by immunoblotting by rhLIGHT treatment. LTßR was constitutively expressed on the surface of human BM-MSCs. Cell number and viability increased after rhLIGHT treatment. BM-MSC proliferation was induced by an increase in the S/G2/M phase. The expression of not only diverse cyclins such as cyclin B1, D1, D3, and E, but also CDK1 and CDK2, increased, while that of p27 decreased, after rhLIGHT treatment. RhLIGHT-induced PDGF and TGFß production mediated by STAT3 and Smad3 activation accelerated BM-MSC proliferation. Thus, LIGHT and LTßR interaction increases the survival and proliferation of human BM-MSCs, and therefore, LIGHT might play an important role in stem cell therapy.
Assuntos
Células da Medula Óssea/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Receptor beta de Linfotoxina/genética , Células-Tronco Mesenquimais/efeitos dos fármacos , Membro 14 da Superfamília de Ligantes de Fatores de Necrose Tumoral/farmacologia , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Proteína Quinase CDC2 , Ciclo Celular , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Condrócitos/citologia , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Quinase 2 Dependente de Ciclina/genética , Quinase 2 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/genética , Ciclinas/metabolismo , Regulação da Expressão Gênica , Humanos , Receptor beta de Linfotoxina/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Análise em Microsséries , Osteócitos/citologia , Osteócitos/efeitos dos fármacos , Osteócitos/metabolismo , Fator de Crescimento Derivado de Plaquetas/genética , Fator de Crescimento Derivado de Plaquetas/metabolismo , Cultura Primária de Células , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Proteína Smad3/genética , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Membro 14 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética , Membro 14 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismoRESUMO
Radotinib is a BCR-ABL1 tyrosine kinase inhibitor approved for the second-line treatment of chronic myeloid leukemia. However, effects of radotinib on acute myeloid leukemia (AML) are unclear. In the present study, we observed that radotinib exerted cytotoxic effects on AML cells. Of the various AML cell lines examined (NB4, HL60, HEL 92.1.7, and THP-1), Kasumi-1 was the most sensitive to radotinib. Results of microarray analysis showed that 417 and 595 genes associated with apoptosis and cell cycle regulation, respectively, were differently expressed (i.e., showed >2-fold difference in expression). Radotinib-induced apoptosis involved the mitochondrial pathway. Moreover, radotinib increased the apoptosis of and induced caspase-3 activity in both Kasumi-1 cells and bone marrow cells (BMCs) obtained from patients with AML. Radotinib also increased cleaved caspase-3, caspase-7, and caspase-9 levels and decreased the number of proliferating Kasumi-1 cells and BMCs from patients with AML. In addition, radotinib induced G0/G1 phase arrest by inducing CDKIs p21 and p27 and by inhibiting CDK2, CDK4, and CDK6. These results indicate that radotinib induces caspase-dependent apoptosis and G0/G1 phase arrest in AML cells by regulating CDKI-CDK-cyclin cascade. Moreover, these results indicate that radotinib inhibits AML cell proliferation by inducing mitochondria-dependent apoptosis and CDKIs p21 and p27. To our knowledge, this is the first study to show that radotinib can be potentially used for the anti-leukemic therapy of patients with AML.
