RESUMO
RAS, TP53 (p53) and MYC are among the most frequently altered driver genes in cancer. Thus, RAS is the most frequently mutated oncogene, MYC the most frequently amplified gene and TP53 the most frequently mutated tumor suppressor gene and overall the most frequently mutated gene in cancer. Theoretically, therefore, these genes are highly attractive targets for cancer treatment. However, as the protein products of each of these genes lack an accessible hydrophobic pocket into which low molecular weight compounds might bind with high affinity, they have proved difficult to target and have traditionally been referred to as "undruggable." Despite this branding, several low molecular weight compounds targeting each of these proteins have recently been reported to have anticancer activity in preclinical models. Indeed, several drugs inhibiting mutant KRAS, MYC overexpression or reactivating mutant p53 have undergone or are currently undergoing clinical trials. For targeting mutant KRAS and reactivating mutant p53, trials have progressed to a Phase III stage, that is, the mutant-p53 reactivating drug, APR-246 is currently being investigated in patients with myelodysplastic syndrome (MDS) and the RAS inhibitor, rigosertib is also undergoing evaluation in patients with MDS. Although there appears to be no directly acting MYC inhibitor currently being tested in a clinical trial, an anti-MYC compound, known as OmoMYC has been extensively validated in multiple preclinical models and is being developed for clinical evaluation. Based on current evidence, the traditional perception of RAS, p53 and MYC as being "undruggable" would appear to be coming to an end.
Assuntos
Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteína Supressora de Tumor p53/agonistas , Animais , Antineoplásicos/uso terapêutico , Sítios de Ligação , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Ensaios Clínicos como Assunto , Avaliação Pré-Clínica de Medicamentos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Mutação , Neoplasias/genética , Proteínas Proto-Oncogênicas c-myc/química , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas p21(ras)/química , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteína Supressora de Tumor p53/química , Proteína Supressora de Tumor p53/genéticaRESUMO
The biological activity of curcumin (CUR), a promising naturally occurring dietary compound for the treatment of hepatocellular carcinoma (HCC), was closely associated with its metabolite. Octahydrocurcumin (OHC) is the final hydrogenated metabolite of CUR and has been reported to have potential biological activities. However, difficulties in access have hampered its biological studies. In the current investigation, we designed an efficient synthesis method to produce OHC, and comparatively explored the anti-cancer effect and potential mechanism of OHC and CUR in an H22 ascites tumor-bearing mice model. The results indicated that OHC had a relatively wide margin of safety, and exhibited superior effects to CUR in suppressing the tumor growth, including ascending weight, abdominal circumference, ascites volume and cancer cell viability. OHC significantly induced H22 cell apoptosis by upregulating the p53 expression and downregulating the MDM2 expression. OHC also remarkably decreased the Bcl-2 and Bcl-xl protein expressions, and increased the Bax and Bad expressions in ascitic cells. Furthermore, THC substantially induced the release of cytochrome C, caspase-3, caspase-9 and the cleavage of PARP to induce H22 cell apoptosis. Taken together, OHC was more effective than CUR in suppressing H22-induced HCC through the activation of the mitochondrial apoptosis pathway. OHC may thus be a promising anti-HCC agent.
Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Apoptose , Carcinoma Hepatocelular/dietoterapia , Curcumina/análogos & derivados , Neoplasias Hepáticas Experimentais/dietoterapia , Animais , Animais não Endogâmicos , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/metabolismo , Proteínas Reguladoras de Apoptose/agonistas , Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Biomarcadores/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , Curcumina/síntese química , Curcumina/metabolismo , Curcumina/uso terapêutico , Regulação Neoplásica da Expressão Gênica , Hidrogenação , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Masculino , Camundongos , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Distribuição Aleatória , Análise de Sobrevida , Carga Tumoral , Proteína Supressora de Tumor p53/agonistas , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismoRESUMO
Concurrent radio chemotherapy treatment prolongs the survival rate of patients with advanced cervical cancer; however, it has adverse sideeffects. ßelemene, an active component of the traditional Chinese medicinal herb Curcuma zedoaria, is a promising alternative therapeutic drug for the treatment of advanced cervical cancer. The aim of the present study was to investigate the antitumor effects of ßelemene in human cervical cancer SiHa cells and to determine its underlying therapeutic molecular mechanisms. Cell viability, cell cycle progression and apoptosis were detected using an MTT assay and flow cytometry analysis. Furthermore, the levels of cell migration and cell invasion were investigated using Transwell and wound healing assays. The expression levels of Cyclindependent kinase inhibitor 2B (P15), Cyclin D1, cellular tumor antigen p53, apoptosis regulator Bcl2 (Bcl2), apoptosis regulator BAX (Bax), 72 kDa type IV collagenase (MMP2), matrix metalloproteinase9 (MMP9), ßcatenin, transcription factor 7 (TCF7), and Myc protooncogene protein (cMyc) were analyzed via western blotting. The results revealed that ßelemene inhibited the proliferation of SiHa cells in a dose and timedependent manner. Administration of ßelemene induced G1 phase cellcycle arrest, as demonstrated by the upregulation of P15 expression and the downregulation of Cyclin D1 expression. Furthermore, the present study revealed that ßelemene induced apoptosis in SiHa cells by enhancing the expression of p53 and Bax, and suppressing the expression of Bcl2. In addition, treatment with ßelemene inhibited cell migration and invasion via downregulation of MMP2 and MMP9 expression levels. Western blotting demonstrated that ßelemene reduced the expression levels of ßcatenin and its downstream target molecule TCF7, thus resulting in reduced levels of their target proteins, including cMyc, Cyclin D1, Bax and MMP2 in cervical cancer cells. The results of the present study suggested that ßelemene may inhibit cell proliferation and invasion, in addition to inducing apoptosis, via attenuation of the Wnt/ßcatenin signaling pathway in cervical cancer cells.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Sesquiterpenos/farmacologia , Transdução de Sinais/efeitos dos fármacos , beta Catenina/genética , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Curcuma/química , Ciclina D1/antagonistas & inibidores , Ciclina D1/genética , Ciclina D1/metabolismo , Inibidor de Quinase Dependente de Ciclina p15/agonistas , Inibidor de Quinase Dependente de Ciclina p15/genética , Inibidor de Quinase Dependente de Ciclina p15/metabolismo , Medicamentos de Ervas Chinesas , Células HeLa , Humanos , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Sesquiterpenos/isolamento & purificação , Transdução de Sinais/genética , Fator 1 de Transcrição de Linfócitos T/antagonistas & inibidores , Fator 1 de Transcrição de Linfócitos T/genética , Fator 1 de Transcrição de Linfócitos T/metabolismo , Proteína Supressora de Tumor p53/agonistas , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/agonistas , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , beta Catenina/antagonistas & inibidores , beta Catenina/metabolismoRESUMO
Arenobufagin, an active component isolated from the traditional Chinese medicine Chan Su, exhibits anticancer influences in several human malignancies. However, the effects and action mechanisms of arenobufagin on non-small-cell lung cancer (NSCLC) are still unknown. In this study, we reported that arenobufagin acted through activation of Noxa-related pathways and promoted apoptotic cell death in human NSCLC cells. Our results revealed that arenobufagin-induced apoptosis was caspase-dependent, as evidenced by the fact that caspase-9, caspase-3 and poly (ADP-ribose) polymerase (PARP) were cleaved, and pretreatment with a pan-caspase inhibitor Z-VAD-FMK inhibited the pro-apoptosis effect of arenobufagin. Mechanistically, we further found that arenobufagin rapidly upregulated the expression of the pro-apoptosis protein Noxa, and abrogated the anti-apoptosis protein Mcl-1, a major binding partner of Noxa in the cell. More importantly, the knockdown of Noxa greatly blocked arenobufagin-induced cell death, highlighting the contribution of this protein in the anti-NSCLC effects of arenobufagin. Interestingly, arenobufagin also increased the expression of p53, a direct transcriptional activator for the upregulation of the Noxa protein. Taken together, our results suggest that arenobufagin is a potential anti-NSCLC agent that triggers apoptotic cell death in NSCLC cells through interfering with the Noxa-related pathway.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Bufanolídeos/química , Bufanolídeos/farmacologia , Regulação Neoplásica da Expressão Gênica , Proteínas Proto-Oncogênicas c-bcl-2/genética , Células A549 , Clorometilcetonas de Aminoácidos/farmacologia , Venenos de Anfíbios/química , Antineoplásicos/isolamento & purificação , Apoptose/genética , Bufanolídeos/isolamento & purificação , Caspase 3/genética , Caspase 3/metabolismo , Caspase 9/genética , Caspase 9/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Medicina Tradicional Chinesa , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia , Transdução de Sinais , Proteína Supressora de Tumor p53/agonistas , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismoRESUMO
Calotropin (M11), an active compound isolated from Asclepias curasavica L., was found to exert strong inhibitory and pro-apoptotic activity specifically against cisplatin-induced resistant non-small cell lung cancer (NSCLC) cells (A549/CDDP). Molecular mechanism study revealed that M11 induced cell cycle arrest at the G2/M phase through down-regulating cyclins, CDK1, CDK2 and up-regulating p53 and p21. Furthermore, M11 accelerated apoptosis through the mitochondrial apoptotic pathway which was accompanied by increase Bax/Bcl-2 ratio, decrease in mitochondrial membrane potential, increase in reactive oxygen species production, activations of caspases 3 and 9 as well as cleavage of poly ADP-ribose polymerase (PARP). The activation and phosphorylation of JNK was also found to be involved in M11-induced apoptosis, and SP610025 (specific JNK inhibitor) partially prevented apoptosis induced by M11. In contrast, all of the effects that M11 induce cell cycle arrest and apoptosis in A549/CDDP cells were not significant in A549 cells. Drugs with higher sensitivity against resistant tumor cells than the parent cells are rather rare. Results of this study supported the potential application of M11 on the non-small lung cancer (NSCLC) with cisplatin resistance.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Asclepias/química , Cardenolídeos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células A549 , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/genética , Proteína Quinase CDC2 , Cardenolídeos/isolamento & purificação , Caspase 3/genética , Caspase 3/metabolismo , Caspase 9/genética , Caspase 9/metabolismo , Cisplatino/farmacologia , Quinase 2 Dependente de Ciclina/antagonistas & inibidores , Quinase 2 Dependente de Ciclina/genética , Quinase 2 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/agonistas , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Quinases Ciclina-Dependentes/antagonistas & inibidores , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , MAP Quinase Quinase 4/genética , MAP Quinase Quinase 4/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Extratos Vegetais/química , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Proteólise , Proteínas Proto-Oncogênicas c-bcl-2/agonistas , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/agonistas , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/agonistas , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismoRESUMO
Sulindac has anti-neoplastic properties against colorectal cancers; however, its use as a chemopreventive agent has been limited due to toxicity and efficacy concerns. Combinatorial treatment of colorectal cancers has been attempted to maximize anti-cancer efficacy with minimal side effects by administrating NSAIDs in combination with other inhibitory compounds or drugs such as l-ascorbic acid (vitamin C), which is known to exhibit cytotoxicity towards various cancer cells at high concentrations. In this study, we evaluated a combinatorial strategy utilizing sulindac and vitamin C. The death of HCT116 cells upon combination therapy occurred via a p53-mediated mechanism. The combination therapeutic resistance developed in isogenic p53 null HCT116 cells and siRNA-mediated p53 knockdown HCT116 cells, but the exogenous expression of p53 in p53 null isogenic cells resulted in the induction of cell death. In addition, we investigated an increased level of intracellular ROS (reactive oxygen species), which was preceded by p53 activation. The expression level of PUMA (p53-upregulated modulator of apoptosis), but not Bim, was significantly increased in HCT116 cells in response to the combination treatment. Taken together, our results demonstrate that combination therapy with sulindac and vitamin C could be a novel anti-cancer therapeutic strategy for p53 wild type colon cancers.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Ácido Ascórbico/metabolismo , Neoplasias do Colo/tratamento farmacológico , Espécies Reativas de Oxigênio/agonistas , Sulindaco/farmacologia , Proteína Supressora de Tumor p53/agonistas , Anti-Inflamatórios não Esteroides/farmacologia , Antioxidantes/metabolismo , Proteínas Reguladoras de Apoptose/agonistas , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Carcinoma/dietoterapia , Carcinoma/tratamento farmacológico , Carcinoma/metabolismo , Neoplasias do Colo/dietoterapia , Neoplasias do Colo/metabolismo , Terapia Combinada , Suplementos Nutricionais , Resistencia a Medicamentos Antineoplásicos , Interações Alimento-Droga , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HCT116 , Humanos , Concentração Osmolar , Oxidantes/metabolismo , Proteínas Proto-Oncogênicas/agonistas , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Interferência de RNA , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismoRESUMO
Plectranthus excisus is widely distributed throughout northeast China. Its active ingredient, diterpenoids, exhibits significant antitumor effects. The present study examined the antitumor effects of diterpenoid B (DB), derived from Plectranthus excisus, and demonstrated that DB inhibited the proliferation of tumor cells by inhibiting the cell cycle. Reverse transcriptionquantitative polymerase chain reaction and western blot analysis were used to determine mRNA and protein expression levels, respectively. The results revealed that exposure to DB increased the expression levels of the transformation associated, protein 53, and cyclindependent kinase inhibitor 1A, and decreased the expression of cyclindependent kinase 2. The results of the present study demonstrated that DB can inhibit cell cycle progression and, therefore, offers potential as a beneficial antitumor drug.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Ciclo Celular/efeitos dos fármacos , Diterpenos/farmacologia , Regulação Neoplásica da Expressão Gênica , Plectranthus/química , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quinase 2 Dependente de Ciclina/antagonistas & inibidores , Quinase 2 Dependente de Ciclina/genética , Quinase 2 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/agonistas , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Diterpenos/isolamento & purificação , Melanoma Experimental/genética , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Extratos Vegetais/química , Transdução de Sinais , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Proteína Supressora de Tumor p53/agonistas , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismoRESUMO
Recently, there are tendency to use natural products such as Ziziphus Jujube (Jujube) as therapeutic agents for cancer. Understanding the molecular mechanisms of anti-cancer effects of Jujube may improve the current therapeutic strategies against cervical cancer. Our MTT data showed a significant dose- and time-dependent inhibition of OV-2008 cell proliferation following Jujube administration. Moreover, qRT-PCR analyses significantly revealed the suppression of cyclin D1 and the enhancement of P53, P21 and P27 expression in treated cells. These results suggest that the herb exerts a cytotoxic effect on cervical cancer cells through alternation of the expression of the genes that are involved in regulation of cell cycle.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Ciclo Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Ziziphus/química , Antineoplásicos Fitogênicos/isolamento & purificação , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Colo do Útero/efeitos dos fármacos , Colo do Útero/metabolismo , Colo do Útero/patologia , Ciclina D1/antagonistas & inibidores , Ciclina D1/genética , Ciclina D1/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/agonistas , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/agonistas , Inibidor de Quinase Dependente de Ciclina p27/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Relação Dose-Resposta a Droga , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Frutas/química , Humanos , Extratos Vegetais/química , Transdução de Sinais , Proteína Supressora de Tumor p53/agonistas , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismoRESUMO
In this study, we used branches Ramulus mori from cultivated mulberry Husang-32 (Morus multicaulis Perry) as the experimental material and anhydrous ethanol as the extraction solution to obtain the crude extract from the branch bark. The ethanolic extract was successively purified through a macroporous resin, Sephadex LH-20, and semipreparative reversed-phase high-performance liquid chromatography (RP-HPLC). The high-purity monomer was identified as morusin by HPLC with diode array detection (HPLC-DAD) and its UV spectrum. The contents of morusin exhibited almost no difference between the root and branch bark in Husang-32, and morusin was not detected in the leaves. Morusin is able to inhibit the tumor growth of transplanted H22 hepatocarcinoma in mice and has no side effects. The fluorescence quantitative real-time PCR (qRT-PCR) results indicate that morusin has a marked inhibitory effect on liver cancer cells through a mechanism that may be related increases in the expression of p53, Survivin, CyclinB1, and Caspase-3 and a decrease in NF-κ B gene expression. The influence of this compound is more apparent in the Caspase-3 and the NF-κ B genes.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Flavonoides/farmacologia , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Morus/química , Casca de Planta/química , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Caspase 3/genética , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Ciclina B1/agonistas , Ciclina B1/genética , Ciclina B1/metabolismo , Etanol , Flavonoides/isolamento & purificação , Proteínas Inibidoras de Apoptose/agonistas , Proteínas Inibidoras de Apoptose/genética , Proteínas Inibidoras de Apoptose/metabolismo , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , NF-kappa B/antagonistas & inibidores , NF-kappa B/genética , NF-kappa B/metabolismo , Extratos Vegetais/química , Raízes de Plantas/química , Proteínas Repressoras/agonistas , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Solventes , Survivina , Carga Tumoral/efeitos dos fármacos , Proteína Supressora de Tumor p53/agonistas , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismoRESUMO
CONTEXT: Shikonin, which is an active naphthoquinone isolated from traditional Chinese herbal medicine Zi Cao, has been recently developed to use as an antitumor agent in colorectal cancer, melanoma, leukemia, breast cancer, and hepatocellular cancer. However, its antitumor effect in thyroid cancer remains largely unknown. OBJECTIVES: The aim of the study was to test the therapeutic potential of shikonin for thyroid cancer and explore the mechanisms underlying antitumor effects of shikonin. EXPERIMENTAL DESIGN: We examined the effects of shikonin on proliferation, cell cycle, apoptosis, migration, invasion, and xenograft tumor growth in thyroid cancer cells and the effect of shikonin on proliferation of primary thyroid cancer cells. RESULTS: Shikonin inhibited thyroid cancer cell proliferation in a dose- and time-dependent manner and induced cell cycle arrest. Moreover, shikonin induced cell apoptosis through reactive oxygen species-mediated DNA damage and activation of the p53 signaling pathway. Our data also showed that shikonin dramatically inhibited thyroid cancer cell migration and invasion by suppressing epithelial-mesenchymal transition and downregulating expression of Slug and MMP-2, -9, and -14. Further elucidation of the mechanisms involved revealed that shikonin markedly repressed the phosphorylation of Erk and Akt and activated the p16/Retinoblastoma protein (Rb) pathway in thyroid cancer cells. Growth of xenograft tumors derived from the thyroid cancer cell line FTC133 in nude mice was significantly inhibited by shikonin. Importantly, we did not find the effect of shikonin on liver function in mice. CONCLUSION: We for the first time demonstrated that shikonin is a potentially effective antitumor agent for thyroid cancers.
Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Inibidor p16 de Quinase Dependente de Ciclina/agonistas , Naftoquinonas/uso terapêutico , Proteína do Retinoblastoma/agonistas , Transdução de Sinais/efeitos dos fármacos , Neoplasias da Glândula Tireoide/tratamento farmacológico , Proteína Supressora de Tumor p53/agonistas , Animais , Antineoplásicos Fitogênicos/efeitos adversos , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Fígado/efeitos dos fármacos , Fígado/fisiopatologia , Camundongos , Camundongos Nus , Proteínas Mutantes/agonistas , Proteínas Mutantes/metabolismo , Naftoquinonas/efeitos adversos , Naftoquinonas/farmacologia , Invasividade Neoplásica/prevenção & controle , Proteínas de Neoplasias/agonistas , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteína do Retinoblastoma/metabolismo , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/fisiopatologia , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
In recent years, an aqueous extract of the fungus Trametes robiniophila Murriell 1907 (Huaier) has been commonly used in China for complementary cancer therapy. However, the mechanisms of its anticancer effects are largely unknown. In the present study, we aimed to investigate the effects of Huaier extract on the inhibition of proliferation and promotion of apoptosis in a melanoma cell line, A875, and to explore the possible mechanisms of its anticancer effects. Cell proliferation was measured using a Cell Counting Kit-8 (CCK8) and PCNA-Western blot. The cell cycle distribution, and apoptosis levels were analyzed by flow cytometry, and Western blot was used to test the apoptotic pathways. We found that Huaier extract strongly inhibited cell proliferation of the A875 melanoma cells and induced G2/M arrest and apoptosis in a time- and dose-dependent manner. P53 expression was increased and cell apoptosis executed by caspase-3. Down-regulation of Bcl-2 and up-regulation of Bcl2-associated X protein (BAX) indicated that Huaier extract induced apoptosis through the mitochondrial pathway. As expected, the inhibitor Huaier decreased melanoma cell line A875 proliferation, and induced apoptosis in a time- and dose-dependent manner. Our findings indicate that Huaier extract is an effective complementary agent for cancer treatment of melanoma.
Assuntos
Antineoplásicos/farmacologia , Produtos Biológicos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Trametes/química , Antineoplásicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Produtos Biológicos/isolamento & purificação , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Medicina Tradicional Chinesa , Mitocôndrias/genética , Mitocôndrias/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/agonistas , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteína Killer-Antagonista Homóloga a bcl-2/antagonistas & inibidores , Proteína Killer-Antagonista Homóloga a bcl-2/genética , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Proteína X Associada a bcl-2/agonistas , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismoRESUMO
BACKGROUND: Induction of cellular senescence through activation of the p53 tumor suppressor protein is a new option for treating proliferative disorders. Nutlins prevent the ubiquitin ligase MDM2 (murine double minute 2), a negative p53 regulator, from interacting with p53. We hypothesized that cell senescence induced by Nutlin-3a exerted therapeutic effects in pulmonary hypertension (PH) by limiting the proliferation of pulmonary artery smooth muscle cells (PA-SMCs). METHODS AND RESULTS: Nutlin-3a treatment of cultured human PA-SMCs resulted in cell growth arrest with the induction of senescence but not apoptosis; increased phosphorylated p53 protein levels; and expression of p53 target genes including p21, Bax, BTG2, and MDM2. Daily intraperitoneal Nutlin-3a treatment for 3 weeks dose-dependently reduced PH, right ventricular hypertrophy, and distal pulmonary artery muscularization in mice exposed to chronic hypoxia or SU5416/hypoxia. Nutlin-3a treatment also partially reversed PH in chronically hypoxic or transgenic mice overexpressing the serotonin-transporter in SMCs (SM22-5HTT+ mice). In these mouse models of PH, Nutlin-3a markedly increased senescent p21-stained PA-SMCs; lung p53, p21, and MDM2 protein levels; and p21, Bax, PUMA, BTG2, and MDM2 mRNA levels; but induced only minor changes in control mice without PH. Marked MDM2 immunostaining was seen in both mouse and human remodeled pulmonary vessels, supporting the use of Nutlins as a PH-targeted therapy. PH prevention or reversal by Nutlin-3a required lung p53 stabilization and increased p21 expression, as indicated by the absence of Nutlin-3a effects in hypoxia-exposed p53(-/-) and p21(-/-) mice. CONCLUSIONS: Nutlin-3a may hold promise as a prosenescence treatment targeting PA-SMCs in PH.
Assuntos
Células Endoteliais/efeitos dos fármacos , Hipertensão Pulmonar/tratamento farmacológico , Imidazóis/uso terapêutico , Piperazinas/uso terapêutico , Proteína Supressora de Tumor p53/agonistas , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/deficiência , Inibidor de Quinase Dependente de Ciclina p21/fisiologia , Avaliação Pré-Clínica de Medicamentos , Regulação da Expressão Gênica/efeitos dos fármacos , Genes p53 , Humanos , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/diagnóstico por imagem , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/patologia , Hipertensão Pulmonar/prevenção & controle , Hipóxia/complicações , Imidazóis/farmacologia , Indóis/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Fosforilação/efeitos dos fármacos , Piperazinas/farmacologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Estabilidade Proteica/efeitos dos fármacos , Artéria Pulmonar/citologia , Artéria Pulmonar/patologia , Pirróis/toxicidade , Proteínas da Membrana Plasmática de Transporte de Serotonina/biossíntese , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/fisiologia , Método Simples-Cego , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/deficiência , UltrassonografiaRESUMO
The tumor suppressor p53 is often inactivated in breast cancer cells because the overexpression of its repressors (e.g., MDM2 and MDMX). Restoration of p53 activity by small molecules through counteracting p53 repressors can lead to in vivo tumor regression and is therefore considered a promising strategy for treatments of cancer. Recent efforts in high-throughput drug screening and rational drug design have identified several structurally diverse small-molecule p53 activators, including a pseudourea derivative XI-011 (NSC146109). This small molecule strongly activates p53 while selectively inhibiting growth of transformed cells without inducing genotoxicity, indicating its potential as a drug lead for p53-targeted therapy. However, the mechanism(s) by which XI-011 activates p53 and the effects of XI-011 on growth of breast cancer cells are currently unknown. Here, we report that XI-011 promoted breast cancer cells to undergo apoptosis through activating p53 and inducing expression of proapoptotic genes. Importantly, we found that activation of p53 by this small molecule was achieved through a novel mechanism, that is, inhibition of MDMX expression. XI-011 repressed the MDMX promoter, resulting in down-regulation of MDMX messenger RNA level in MCF-7 cells. In line with these results, XI-011 decreased the viability of breast cancer cells expressing low levels of MDMX in a less-efficient manner. Interestingly, XI-011 acted additively with the MDM2 antagonist Nutlin-3a to inhibit growth of breast cancer cells. We conclude that XI-011 belongs to a novel class of small-molecule p53 activators that target MDMX and could be of value in treating breast cancer.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/genética , Carcinoma/genética , Proteínas Nucleares/genética , Proteínas Proto-Oncogênicas/genética , Proteína Supressora de Tumor p53/agonistas , Antracenos/administração & dosagem , Antracenos/farmacologia , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma/metabolismo , Carcinoma/patologia , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Avaliação Pré-Clínica de Medicamentos , Sinergismo Farmacológico , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imidazóis/administração & dosagem , Modelos Biológicos , Peso Molecular , Proteínas Nucleares/metabolismo , Proteínas Nucleares/fisiologia , Piperazinas/administração & dosagem , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas/fisiologia , Tioureia/administração & dosagem , Tioureia/análogos & derivados , Tioureia/farmacologia , Células Tumorais CultivadasRESUMO
High-throughput screening is an essential component of the toolbox of modern technologies that improve speed and efficiency in contemporary cancer drug development. This is particularly important as we seek to exploit, for maximum therapeutic benefit, the large number of new molecular targets emerging from the Human Genome Project and cancer genomics. Screening of diverse collections of low molecular weight compounds plays a key role in providing chemical starting points for iterative optimisation by medicinal chemistry. Examples of successful drug discovery programmes based on high-throughput screening are described, and these offer potential in the treatment of breast cancer and other malignancies.