RESUMEN
BACKGROUND/AIMS: Coumarins are natural compounds found in many plants that possess medical value by itself and its modified derivatives. METHOD: Six novel coumarin derivatives were synthesized and examined for their potential anticancer cytotoxicity. RESULT: Among the 6 derivatives, 3,5-dimethyl-(7)H-furo[3,2-g]chromen-7-one (DMFC) presented the strongest cytotoxicity against human hepatoma HepG2 cells in vitro with an IC(50) value of 8.46 ± 0.28 µM in a 48-hour treatment. Further experiments revealed that DMFC induced apoptosis in HepG2 cells through both extrinsic and intrinsic apoptotic pathways in a p53-dependent manner. Mechanistically, DMFC activated caspases 3, 8 and 9, depolarized mitochondrial membrane potential and induced cytochrome c and apoptosis-inducing factor release. DMFC-induced apoptosis was also characterized by DNA fragmentation, phosphatidylserine externalization and sub-G1 peak in DNA histograms. Moreover, both caspase 8 and 9 inhibitors suppressed the apoptosis induced by DMFC. Western blot analyses revealed that DMFC also significantly increased the expression levels of p53, Fas death receptor, Fas-associated death domain protein and proapoptotic Bcl-2 family members such as Bax, Bad and tBid, as well as decreased the levels of pro-survival members such as Bcl-2 and Bcl-xl. CONCLUSION: DMFC is potentially an effective therapeutic agent in liver cancer therapy.
Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Benzofuranos/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Cumarinas/farmacología , Neoplasias Hepáticas/tratamiento farmacológico , Proteína p53 Supresora de Tumor/metabolismo , Factor Inductor de la Apoptosis/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Caspasas/metabolismo , Citocromos c/metabolismo , Fragmentación del ADN/efectos de los fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Fosfatidilserinas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteína p53 Supresora de Tumor/biosíntesis , Proteína p53 Supresora de Tumor/genética , Proteína bcl-X/biosíntesis , Proteína bcl-X/genética , Receptor fas/biosíntesis , Receptor fas/genéticaRESUMEN
Ovarian cancer is associated with a high mortality rate due to diagnosis at advanced stages. Dissemination often occurs intraperitoneally within the ascites fluid. The microenvironment can support dissemination through several mechanisms. One potential ascites factor which may mediate dissemination are EVs or extracellular vesicles that can carry information in the form of miRNAs, proteins, lipids, and act as mediators of cellular communication. We present our observations on EVs isolated from ascitic supernatants from patients diagnosed with high grade serous ovarian carcinoma in augmenting motility, growth, and migration towards omental fat. MicroRNA profiling of EVs from malignant ascitic supernatant demonstrates high expression of miR 200c-3p, miR18a-5p, miR1246, and miR1290 and low expression of miR 100- 5p as compared to EVs isolated from benign ascitic supernatant. The migration of ovarian cancer spheroids towards omental fat is enhanced in the presence of malignant ascitic EVs. Gene expression of these cells showed increased expression of ZBED2, ZBTB20, ABCC3, UHMK1, and low expression of Transgelin and MARCKS. We present evidence that ovarian ascitic EVs increase the growth of ovarian cancer spheroids through miRNAs.
Asunto(s)
Líquido Ascítico/metabolismo , Vesículas Extracelulares/metabolismo , Neoplasias Ováricas/patología , Anciano , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Femenino , Humanos , MicroARNs/metabolismo , MicroARNs/farmacología , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/metabolismo , Persona de Mediana Edad , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Neoplasias Ováricas/metabolismo , Esferoides Celulares/citología , Esferoides Celulares/metabolismo , Microambiente Tumoral , Regulación hacia Arriba/efectos de los fármacosRESUMEN
Oncogenic protein E6 of human papillomavirus type 16 (HPV-16) is believed to involve in the aberrant methylation in cervical cancer as it upregulates DNA methyltransferase 1 (DNMT1) through tumor suppressor p53. In addition, DNA demethylating agent induces the expression of one of the HPV-16 E6 regulated microRNAs (miRs), miR-23b, in human cervical carcinoma SiHa cells. Thus, the importance of DNA methylation and miR-23b in HPV-16 E6 associated cervical cancer development is investigated. In the present study, however, it is found that miR-23b is not embedded in any typical CpG island. Nevertheless, a functional CpG island is predicted in the promoter region of C9orf3, the host gene of miR-23b, and is validated by methylation-specific PCR and bisulfite genomic sequencing analyses. Besides, c-MET is confirmed to be a target gene of miR-23b. Silencing of HPV-16 E6 is found to increase the expression of miR-23b, decrease the expression of c-MET and thus induce the apoptosis of SiHa cells through the c-MET downstream signaling pathway. Taken together, the tumor suppressive miR-23b is epigenetically inactivated through its host gene C9orf3 and this is probably a critical pathway during HPV-16 E6 associated cervical cancer development.
Asunto(s)
Aminopeptidasas/genética , Metilación de ADN , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Proteínas Oncogénicas Virales/genética , Proteínas Represoras/genética , Apoptosis/efectos de los fármacos , Apoptosis/genética , Azacitidina/análogos & derivados , Azacitidina/farmacología , Western Blotting , Línea Celular Tumoral , ADN (Citosina-5-)-Metiltransferasa 1 , ADN (Citosina-5-)-Metiltransferasas/antagonistas & inhibidores , ADN (Citosina-5-)-Metiltransferasas/genética , ADN (Citosina-5-)-Metiltransferasas/metabolismo , Decitabina , Inhibidores Enzimáticos/farmacología , Femenino , Células HCT116 , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/metabolismo , Papillomavirus Humano 16/fisiología , Humanos , Regiones Promotoras Genéticas/genética , Proteínas Proto-Oncogénicas c-met/genética , Proteínas Proto-Oncogénicas c-met/metabolismo , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/virologíaRESUMEN
BAD (BCL-2 antagonist of cell death) is a pro-apoptotic BCL-2 family protein that plays a critical role in the regulation of apoptotic response. This study presents direct evidence that AF1q increased the radiation-induced apoptosis through up-regulation of BAD in human squamous carcinoma A431 cells and the key transcription factor involved is NF-kappaB. The minimal promoter sequence of BAD was identified; the activity was increased in AF1q stable transfectants and decreased upon AF1q siRNA transfection. The NF-kappaB consensus binding sequence is detected on BAD promoter. Inactivation of NF-kappaB by NF-kappaB inhibitor Bay 11-7082 or NF-kappaB p65 siRNA suppressed the expression and promoter activity of BAD; the suppression is more obvious in AF1q stable transfectants which also have an elevated NF-kappaB level. Mutation of putative NF-kappaB motif decreased the BAD promoter activity. The binding of NF-kappaB to the BAD promoter was confirmed by chromatin-immunoprecipitation. These findings indicate that AF1q up-regulation of BAD is through its effect on NF-kappaB and this may hint of its oncogenic mechanism in cancer.