RESUMO
Angiogenesis is involved in the malignant transformation of cancers. Vascular endothelial growth factor (VEGF) is important in inducing angiogenesis. Cultured cells play an important role in analyzing the regulation of VEGF expression, and it is revealed that VEGF expression is induced under hypoxia. However, it has been shown that there are differences in the pathway for gene expression between two-dimensional (2D) cells and in vivo cells. Three-dimensional (3D) spheroids constructed in 3D culture with a gene expression pattern more similar to that of in vivo cells than 2D cells have been used to solve this problem. This study analyzed the VEGF gene expression pathway in 3D spheroids of human lung cancer cells, A549 and H1703. Hypoxia-inducible factor-1α (HIF-1α) and aryl hydrocarbon receptor nuclear translocator (ARNT) regulated VEGF gene expression in 3D spheroids. However, VEGF gene expression was not regulated by HIF-1α in 2D cells. To conclude, we found that the regulatory pathway of VEGF gene expression is different between 2D cells and 3D spheroids in human lung cancer cells. These results suggest the possibility of a new VEGF gene expression regulation pathway in vivo. In addition, they show useful knowledge for the analysis of angiogenesis induction mechanisms and also demonstrate the usefulness of 3D spheroids.
Assuntos
Neoplasias Pulmonares , Fator A de Crescimento do Endotélio Vascular , Humanos , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Fatores de Crescimento do Endotélio Vascular/metabolismo , Translocador Nuclear Receptor Aril Hidrocarboneto/genética , Translocador Nuclear Receptor Aril Hidrocarboneto/metabolismo , Regulação da Expressão Gênica , Neoplasias Pulmonares/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismoRESUMO
The aryl hydrocarbon receptor (AhR) is activated by the ligand, benzo[a]pyrene (B[a]P), a component of smoke that is implicated in lung carcinogenesis in humans. However, the role of B[a]P and AhR in lung cancer malignancy is not well known. In this study, we analyzed the effects of B[a]P and AhR in the 3 D spheroids of human lung cancer cells in vitro. In these spheroids, B[a]P and AhR enhanced cancer cell proliferation. These results suggest that the AhR-dependent effects of B[a]P on cell proliferation may contribute to the adverse effects of continuous smoking with respect to lung cancer malignancy.
Assuntos
Adenocarcinoma de Pulmão/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/agonistas , Benzo(a)pireno/toxicidade , Proliferação de Células/efeitos dos fármacos , Neoplasias Pulmonares/metabolismo , Receptores de Hidrocarboneto Arílico/agonistas , Células A549 , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais , Esferoides CelularesRESUMO
Most of cytochrome P450 (CYP) expressions are regulated by nuclear receptors. The regulation pathways of transcription are activated by binding of the ligand to the receptor. Many combination of CYPs and nuclear receptors in transcriptional regulation have been reported. However, we have reported that the combination changes depending on culture condition on the same type of cells. The regulation pathway of CYP1A expression is different between 2D monolayer cultured cells and 3D spheroids of human liver cancer cells. Aryl hydrocarbon receptor (AhR) is one of the transcription factors for CYP1A and CYP1B1 expression, and this pathway is important for inducing human lung cancer. CYP1B1 expression in human lung cancer cells are regulated by AhR in 2D and 3D cells. But CYP1A expression are not induced by AhR in 3D cells. As with liver cancer cells, the function of AhR in lung cancer cells is different between 2D cells and 3D spheroids. These results important for understanding relationship between AhR and CYP expression before and after cell neoplastic formation in human lung.
