RESUMO
BACKGROUND: Non-small cell lung cancer (NSCLC) is one of the leading causes of death in the world. NSCLC diagnosed at an early stage can be highly curable with a positive prognosis, but biomarker limitations make it difficult to diagnose lung cancer at an early stage. To identify biomarkers for lung cancer development, we previously focused on the oncogenic roles of transcription factor TFAP2C in lung cancers and revealed the molecular mechanism of several oncogenes in lung tumorigenesis based on TFAP2C-related microarray analysis. RESULTS: In this study, we analyzed microarray data to identify tumor suppressor genes and nine genes downregulated by TFAP2C were screened. Among the nine genes, we focused on growth arrest and DNA-damage-inducible beta (GADD45B) and phorbol-12-myristate-13-acetate-induced protein 1 (PMAIP1) as representative TFAP2C-regulated tumor suppressor genes. It was observed that overexpressed TFAP2C resulted in inhibition of GADD45B and PMAIP1 expressions at both the mRNA and protein levels in NSCLC cells. In addition, downregulation of GADD45B and PMAIP1 by TFAP2C promoted cell proliferation and cell motility, which are closely associated with NSCLC tumorigenesis. CONCLUSION: This study indicates that GADD45B and PMAIP1 could be promising tumor suppressors for NSCLC and might be useful as prognostic markers for use in NSCLC therapy.
Assuntos
Antígenos de Diferenciação/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Proliferação de Células/genética , Regulação para Baixo/genética , Neoplasias Pulmonares/genética , Fator de Transcrição AP-2/genética , Biomarcadores Tumorais/análise , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor/fisiologia , Humanos , RNA Mensageiro/análise , RNA Interferente Pequeno/análiseRESUMO
BACKGROUND: Non-small cell lung cancer (NSCLC) is one of the leading causes of death in the world. NSCLC diagnosed at an early stage can be highly curable with a positive prognosis, but biomarker limitations make it difficult to diagnose lung cancer at an early stage. To identify biomarkers for lung cancer development, we previously focused on the oncogenic roles of transcription factor TFAP2C in lung cancers and revealed the molecular mechanism of several oncogenes in lung tumorigenesis based on TFAP2C-related microarray analysis. RESULTS: In this study, we analyzed microarray data to identify tumor suppressor genes and nine genes downregulated by TFAP2C were screened. Among the nine genes, we focused on growth arrest and DNA-damage-inducible beta (GADD45B) and phorbol-12-myristate-13-acetate-induced protein 1 (PMAIP1) as representative TFAP2C-regulated tumor suppressor genes. It was observed that overexpressed TFAP2C resulted in inhibition of GADD45B and PMAIP1 expressions at both the mRNA and protein levels in NSCLC cells. In addition, downregulation of GADD45B and PMAIP1 by TFAP2C promoted cell proliferation and cell motility, which are closely associated with NSCLC tumorigenesis. CONCLUSION: This study indicates that GADD45B and PMAIP1 could be promising tumor suppressors for NSCLC and might be useful as prognostic markers for use in NSCLC therapy.
Assuntos
Humanos , Antígenos de Diferenciação/genética , Regulação para Baixo/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Proliferação de Células/genética , Fator de Transcrição AP-2/genética , Neoplasias Pulmonares/genética , RNA Mensageiro/análise , Biomarcadores Tumorais/análise , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor/fisiologia , RNA Interferente Pequeno/análise , Linhagem Celular TumoralRESUMO
During radiotherapy, an inflammatory response might be induced by activating various enzymes involved in membrane lipid metabolism. The eicosanoid pathway associated with cytosolic phospholipase A2 (cPLA2), cyclooxygenases (COXs), and lipoxygenases (LOXs) can be induced by radiation, and many lipid metabolites might contribute to cancer-associated inflammation, cell proliferation, and cell survival in cancer. The lipid metabolites are also involved in the establishment of the tumor-associated microenvironment through promotion of angiogenesis and formation of vascular network. These biological activities of lipid metabolites are responsible for malignant progression with the acquisition of radioresistance, leading to unsatisfactory outcome of cancer radiotherapy. Many efforts have been made to identify the mechanisms associated with bioactive lipid metabolites and radiation signaling that lead to radioresistance and to develop potent radiosensitizers to improve therapeutic efficacy. Beneficial outcomes would be achieved by targeting the enzymes, such as cPLA2, COXs, and LOXs, responsible for arachidonic acid metabolism and cancer-associated inflammation during cancer radiotherapy. The current study demonstrated a brief review for the radioresistant effects of bioactive lipid metabolites and their enzymes in cancer and the radiosensitizing effects of inhibitors for the enzymes on cancer therapy.
Assuntos
Ácidos Araquidônicos/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos da radiação , Metabolismo dos Lipídeos/efeitos da radiação , Neoplasias/metabolismo , Neoplasias/radioterapia , Animais , Araquidonato 5-Lipoxigenase/metabolismo , Biomarcadores , Ensaios Clínicos como Assunto , Terapia Combinada , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Suscetibilidade a Doenças , Ativação Enzimática/efeitos da radiação , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Neoplasias/enzimologia , Neoplasias/genética , Fosfolipases A2 Citosólicas/genética , Fosfolipases A2 Citosólicas/metabolismo , Prognóstico , Tolerância a Radiação/efeitos dos fármacos , Tolerância a Radiação/genética , Tolerância a Radiação/efeitos da radiação , Resultado do TratamentoRESUMO
Long non-coding RNAs (lncRNAs) are classified as RNAs that are longer than 200 nucleotides and cannot be translated into protein. Several studies have demonstrated that lncRNAs are directly or indirectly involved in a variety of biological processes and in the regulation of gene expression. In addition, lncRNAs have important roles in many diseases including cancer. It has been shown that abnormal expression of lncRNAs is observed in several human solid tumors. Several studies have shown that many lncRNAs can function as oncogenes in cancer development through the induction of cell cycle progression, cell proliferation and invasion, anti-apoptosis, and metastasis. Oncogenic lncRNAs have the potential to become promising biomarkers and might be potent prognostic targets in cancer therapy. However, the biological and molecular mechanisms of lncRNA involvement in tumorigenesis have not yet been fully elucidated. This review summarizes studies on the regulatory and functional roles of oncogenic lncRNAs in the development and progression of various types of cancer.
RESUMO
Thelephoric acid is an antioxidant produced by the hydrolysis of polyozellin, which is isolated from Polyozellus multiplex. In the present study, the inhibitory effects of polyozellin and thelephoric acid on 9 cytochrome P450 (CYP) family members (CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, and CYP3A4) were examined in pooled human liver microsomes (HLMs) using a cocktail probe assay. Polyozellin exhibited weak inhibitory effects on the activities of all 9 CYPs examined, whereas thelephoric acid exhibited dose- and time-dependent inhibition of all 9 CYP isoforms (IC50 values, 3.2-33.7 µM). Dixon plots of CYP inhibition indicated that thelephoric acid was a competitive inhibitor of CYP1A2 and CYP3A4. In contrast, thelephoric acid was a noncompetitive inhibitor of CYP2D6. Our findings indicate that thelephoric acid may be a novel, non-specific CYP inhibitor, suggesting that it could replace SKF-525A in inhibitory studies designed to investigate the effects of CYP enzymes on the metabolism of given compounds.