RESUMO
Wnt/ß-catenin signaling is frequently activated in advanced prostate cancer and contributes to therapy resistance and metastasis. However, activating mutations in the Wnt/ß-catenin pathway are not common in prostate cancer, suggesting alternative regulations may exist. Here, we report that the expression of endothelial cell-specific molecule 1 (ESM1), a secretory proteoglycan, is positively associated with prostate cancer stemness and progression by promoting Wnt/ß-catenin signaling. Elevated ESM1 expression correlates with poor overall survival and metastasis. Accumulation of nuclear ESM1, instead of cytosolic or secretory ESM1, supports prostate cancer stemness by interacting with the ARM domain of ß-catenin to stabilize ß-catenin-TCF4 complex and facilitate the transactivation of Wnt/ß-catenin signaling targets. Accordingly, activated ß-catenin in turn mediates the nuclear entry of ESM1. Our results establish the significance of mislocalized ESM1 in driving metastasis in prostate cancer by coordinating the Wnt/ß-catenin pathway, with implications for its potential use as a diagnostic or prognostic biomarker and as a candidate therapeutic target in prostate cancer.
Assuntos
Núcleo Celular/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/secundário , Proteínas de Neoplasias/metabolismo , Células-Tronco Neoplásicas/patologia , Neoplasias da Próstata/patologia , Proteoglicanas/metabolismo , beta Catenina/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/metabolismo , Prognóstico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Proteoglicanas/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/genéticaRESUMO
BACKGROUND: KH-type splicing regulatory protein (KHSRP, also called KSRP), a versatile RNA-binding protein, plays a critical role in various physiological and pathological conditions through modulating gene expressions at multiple levels. However, the role of KSRP in clear cell renal cell carcinoma (ccRCC) remains poorly understood. METHODS: KSRP expression was detected by a ccRCC tissue microarray and evaluated by an in silico analysis. Cell loss-of-function and gain-of-function, colony-formation, anoikis, and transwell assays, and an orthotopic bioluminescent xenograft model were conducted to determine the functional role of KRSP in ccRCC progression. Micro (mi)RNA and complementary (c)DNA microarrays were used to identify downstream targets of KSRP. Western blotting, quantitative real-time polymerase chain reaction, and promoter- and 3-untranslated region (3'UTR)-luciferase reporter assays were employed to validate the underlying mechanisms of KSRP which aggravate progression of ccRCC. RESULTS: Our results showed that dysregulated high levels of KSRP were correlated with advanced clinical stages, larger tumor sizes, recurrence, and poor prognoses of ccRCC. Neural precursor cell-expressed developmentally downregulated 4 like (NEDD4L) was identified as a novel target of KSRP, which can reverse the protumorigenic and prometastatic characteristics as well as epithelial-mesenchymal transition (EMT) promotion by KSRP in vitro and in vivo. Molecular studies revealed that KSRP can decrease NEDD4L messenger (m)RNA stability via inducing mir-629-5p upregulation and directly targeting the AU-rich elements (AREs) of the 3'UTR. Moreover, KSRP was shown to transcriptionally suppress NEDD4L via inducing the transcriptional repressor, Wilm's tumor 1 (WT1). In the clinic, ccRCC samples revealed a positive correlation between KSRP and mesenchymal-related genes, and patients expressing high KSRP and low NEDD4L had the worst prognoses. CONCLUSION: The current findings unveil novel mechanisms of KSRP which promote malignant progression of ccRCC through transcriptional inhibition and post-transcriptional destabilization of NEDD4L transcripts. Targeting KSRP and its pathways may be a novel pharmaceutical intervention for ccRCC.
Assuntos
Carcinoma de Células Renais , Neoplasias Renais , MicroRNAs , Proteínas de Ligação a RNA , Humanos , Regiões 3' não Traduzidas , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Ubiquitina/metabolismoRESUMO
A disintegrin and metalloprotease with thrombospondin motifs (ADAMTS) family are widely implicated in tissue remodeling events manifested in cancer development. ADAMTS1, the most fully characterized ADAMTS, plays conflicting roles in different cancer types; however, the role of ADAMTS1 in renal cell carcinoma (RCC) remains unclear. Herein, we found that ADAMTS1 is highly expressed in RCC tissues compared to normal renal tissues, and its expression was correlated with an advanced stage and a poor prognosis of RCC patients. In vitro, we observed higher expression of ADAMTS1 in metastatic (m)RCC cells compared to primary cells, and manipulation of ADAMTS1 expression affected cell invasion and clonogenicity. Results from protease array showed that ADAMTS1 is modulated by melatonin through mechanisms independent of the MT1 receptor in mRCC cells, and overexpression of ADAMTS1 relieved the invasion/clonogenicity and growth/metastasis inhibition imposed by melatonin treatment in vitro and in an orthotopic xenograft model. The human microRNA (miR) OneArray showed that miR-181d and miR-let-7f were induced by melatonin and, respectively, targeted the 3'-UTR and non-3'-UTR of ADAMTS1 to suppress its expression and mRCC invasive ability. Clinically, RCC patients with high levels of miR-181d or miR-let-7f and a low level of ADAMTS1 had the most favorable prognoses. In addition, ubiquitin/proteasome-mediated degradation of ADAMTS1 can also be triggered by melatonin. Together, our study indicates that ADAMTS1 may be a useful biomarker for predicting RCC progression. The novel convergence between melatonin and ADAMTS1 post-transcriptional and post-translational regulation provides new insights into the role of melatonin-induced molecular regulation in suppressing RCC progression.
Assuntos
Proteína ADAMTS1/metabolismo , Carcinogênese/metabolismo , Carcinoma de Células Renais/metabolismo , Neoplasias Renais/metabolismo , Melatonina/farmacologia , Proteínas de Neoplasias/metabolismo , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteína ADAMTS1/genética , Animais , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Humanos , Neoplasias Renais/genética , Neoplasias Renais/patologia , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Metástase Neoplásica , Proteínas de Neoplasias/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Chemotherapy is the main treatment for acute myeloid leukemia (AML), but the cure rates for AML patients remain low, and the notorious adverse effects of chemotherapeutic drugs drastically reduce the life quality of patients. Penfluridol, a long-acting oral antipsychotic drug, has an outstanding safety record and exerts oncostatic effects on various solid tumors. Until now, the effect of penfluridol on AML remains unknown. METHODS: AML cell lines harboring wild-type (WT) Fms-like tyrosine kinase 3 (FLT3) and internal tandem duplication (ITD)-mutated FLT3 were used to evaluate the cytotoxic effects of penfluridol by an MTS assay. A flow cytometric analysis and immunofluorescence staining were employed to determine the cell-death phenotype, cell cycle profile, and reactive oxygen species (ROS) and acidic vesicular organelle (AVO) formation. Western blotting and chemical inhibitors were used to explore the underlying mechanisms involved in penfluridol-mediated cell death. RESULTS: We observed that penfluridol concentration-dependently suppressed the cell viability of AML cells with FLT3-WT (HL-60 and U937) and FLT3-ITD (MV4-11). We found that penfluridol treatment not only induced apoptosis as evidenced by increases of nuclear fragmentation, the sub-G1 populations, poly (ADP ribose) polymerase (PARP) cleavage, and caspase-3 activation, but also triggered autophagic responses, such as the light chain 3 (LC3) turnover and AVO formation. Interestingly, blocking autophagy by the pharmacological inhibitors, 3-methyladenine and chloroquine, dramatically enhanced penfluridol-induced apoptosis, indicating the cytoprotective role of autophagy in penfluridol-treated AML cells. Mechanistically, penfluridol-induced apoptosis occurred through activating protein phosphatase 2A (PP2A) to suppress Akt and mitogen-activated protein kinase (MAPK) activities. Moreover, penfluridol's augmentation of intracellular ROS levels was critical for the penfluridol-induced autophagic response. In the clinic, we observed that patients with AML expressing high PP2A had favorable prognoses. CONCLUSIONS: These findings provide a rationale for penfluridol being used as a PP2A activator for AML treatment, and the combination of penfluridol with an autophagy inhibitor may be a novel strategy for AML harboring FLT3-WT and FLT3-ITD.
Assuntos
Antipsicóticos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Leucemia Mieloide Aguda/tratamento farmacológico , Penfluridol/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Tirosina Quinase 3 Semelhante a fms/metabolismo , Linhagem Celular Tumoral , Citoproteção/efeitos dos fármacos , Células HL-60 , Humanos , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteína Fosfatase 2/genética , Proteína Fosfatase 2/metabolismo , Transdução de Sinais , Células U937RESUMO
Metastasis is the major cause of death from lung cancer. Quercetin, a widely distributed bioflavonoid, is well known to induce growth inhibition in a variety of human cancer cells, but how it affects lung cancer cell invasion and metastasis is unclear. Herein, we found that quercetin inhibited the migration/invasion of non-small cell lung cancer (NSCLC) cell lines and bone metastasis in an orthotopic A549 xenograft model by suppressing the Snail-mediated epithelial-to-mesenchymal transition (EMT). Moreover, survival times of animals were also prolonged after quercetin treatment. Mechanistic investigations found that quercetin suppressed Snail-dependent Akt activation by upregulating maspin and Snail-independent a disintegrin and metalloproteinase (ADAM) 9 expression pathways to modulate the invasive ability of NSCLC cells. In clinical samples, we observed that patients with Snailhigh/p-Akthigh tumors had the shortest survival times. In addition, a lower survival rate was also found in ADAM9high patients than in ADAM9low patients. Overall, our results provide new insights into the role of quercetin-induced molecular regulation in suppressing NSCLC metastasis and suggest that quercetin has potential therapeutic applications for metastatic NSCLC.
Assuntos
Proteínas ADAM/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Proteínas de Membrana/genética , Proteína Oncogênica v-akt/genética , Quercetina/administração & dosagem , Serpinas/genética , Fatores de Transcrição da Família Snail/genética , Células A549 , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND/AIMS: Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) therapy is a clinical option for non-small cell lung cancer (NSCLC) harboring activating EGFR mutations or for cancer with wild-type (WT) EGFR when chemotherapy has failed. MET receptor activation or MET gene amplification was reported to be a major mechanism of acquired resistance to EGFR-TKI therapy in NSCLC cells. Leukocyte cell-derived chemotaxin 2 (LECT2) is a multifunctional cytokine that was shown to suppress metastasis of hepatocellular carcinoma via inhibiting MET activity. Until now, the biological function responsible for LECT2's action in human NSCLC remains unclear. METHODS: LECT2-knockout (KO) mice and NOD/SCID/IL2rgnull (NSG) mice were respectively used to investigate the effects of LECT2 on the tumorigenicity and metastasis of murine (Lewis lung carcinoma, LLC) and human (HCC827) lung cancer cells. The effect of LECT2 on in vitro cell proliferation was evaluated, using MTS and colony formation assays. The effect of LECT2 on cell motility was evaluated using transwell migration and invasion assays. An enzyme-linked immunosorbent assay was performed to detect secreted LECT2 in plasma and media. Co-immunoprecipitation and Western blot assays were used to investigate the underlying mechanisms of LECT2 in NSCLC cells. RESULTS: Compared to WT mice, mice with LECT2 deletion exhibited enhanced growth and metastasis of LLC cells, and survival times decreased in LLC-implanted mice. Overexpression of LECT2 in orthotopic human HCC827 xenografts in NSG mice resulted in significant inhibition of tumor growth and metastasis. In vitro, overexpression of LECT2 or treatment with a recombinant LECT2 protein impaired the colony-forming ability and motility of NSCLC cells (HCC827 and PC9) harboring high levels of activated EGFR and MET. Mechanistic investigations found that LECT2 bound to MET and EGFR to antagonize their activation and further suppress their common downstream pathways: phosphatidylinositol 3-kinase/Akt and extracellular signal-regulated kinase. CONCLUSION: EGFR-MET signaling is critical for aggressive behaviors of NSCLC and is recognized as a therapeutic target for NSCLC especially for patients with acquired resistance to EGFR-TKI therapy. Our findings demonstrate, for the first time, that LECT2 functions as a suppressor of the progression of NSCLC by targeting EGFR-MET signaling.
Assuntos
Receptores ErbB/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Receptores ErbB/genética , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/deficiência , Peptídeos e Proteínas de Sinalização Intercelular/genética , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Metástase Neoplásica , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/farmacologia , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Luteolin (3',4',5,7-tetrahydroxyflavone), which exists in fruits, vegetables, and medicinal herbs, is used in Chinese traditional medicine for treating various diseases, such as hypertension, inflammatory disorders, and cancer. However, the gene-regulatory role of luteolin in cancer prevention and therapy has not been clarified. Herein, we demonstrated that treatment with luteolin resulted in a significant decrease in the viability of human leukemia cells. In the present study, by evaluating fragmentation of DNA and poly (ADP-ribose) polymerase (PARP), we found that luteolin was able to induce PARP cleavage and nuclear fragmentation as well as an increase in the sub-G0 /G1 fraction. In addition, luteolin also induced Fas and Fas ligand (FasL) expressions and subsequent activation of caspases-8 and -3, which can trigger the extrinsic apoptosis pathway, while knocking down Fas-associated protein with death domain (FADD) prevented luteolin-induced PARP cleavage. Immunoblot and chromatin immunoprecipitation (ChIP) analyses revealed that luteolin increased acetylation of histone H3, which is involved in the upregulation of Fas and FasL. Moreover, both the extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) pathways are involved in luteolin-induced histone H3 acetylation. Finally, luteolin also activated the c-Jun signaling pathway, which contributes to FasL, but not Fas, gene expression and downregulation of c-Jun expression by small interfering RNA transfection which resulted in a significant decrease in luteolin-induced PARP cleavage. Thus, our results demonstrate that luteolin induced apoptosis of HL-60 cells, and this was associated with c-Jun activation and histone H3 acetylation-mediated Fas/FasL expressions.
Assuntos
Apoptose/efeitos dos fármacos , Proteína Ligante Fas/metabolismo , Histonas/metabolismo , Leucemia/tratamento farmacológico , Luteolina/farmacologia , Proteínas Proto-Oncogênicas c-jun/metabolismo , Receptor fas/metabolismo , Acetilação/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 8/metabolismo , Linhagem Celular Tumoral , Proteína de Domínio de Morte Associada a Fas/metabolismo , Células HL-60 , Humanos , Leucemia/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Células U937 , Regulação para Cima/efeitos dos fármacosRESUMO
Nonsmall cell lung cancer (NSCLC) is the most common type of lung cancer with a high mortality rate and still remains a therapeutic challenge. A strategy for targeting NSCLC is to identify agents that are effective against NSCLC cells while sparing normal cells. Dihydromyricetin (DHM) is the major flavonoid component derived from Ampelopsis grossedentata, which has a long history of use in medicine. Herein, the molecular mechanisms by which DHM exerts its anticancer effects against NSCLC cells were investigated. Results from MTS, colony formation, Western blot, flow cytometric, and JC-1 mitochondrial membrane potential assays revealed that DHM showed a selective cytotoxic effect against NSCLC cells (A549 and H1975), but not against normal lung (WI-38) fibroblasts, by inducing apoptosis. DHM-induced cell apoptosis occurred through Bcl-w suppression-mediated mitochondrial membrane depolarization, caspase-9/-7/-3 activation, and poly(ADP-ribose) polymerase (PARP) cleavage in A549 and H1975 cells. Moreover, treatment of A549 and H1975 cells with DHM induced increase of intracellular peroxide and sustained activation of extracellular signal-regulated kinase (ERK)1/2 and c-Jun N-terminal kinase (JNK)1/2, and the reactive oxygen species scavenger, N-acetylcysteine (NAC), reversed DHM-induced ERK and JNK activation. Furthermore, treatment of cells with specific inhibitors of ERK and JNK or NAC significantly promoted the DHM-induced activation of caspase-9/-7/-3 and PARP cleavage and also sensitized the antitumorigenic effect of DHM on NSCLC cells. These findings define and support a novel function of DHM of inducing mitochondrion-derived apoptosis in human NSCLC cells, and a combination of DHM with ERK and JNK inhibitors should be a good strategy for preventing NSCLC proliferation. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1426-1438, 2017.
Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Flavonóis/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Células A549 , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Ativação Enzimática , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Sistema de Sinalização das MAP Quinases , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismoRESUMO
Apigenin (4',5,7-trihydroxyflavone), a flavonoid commonly found in fruits and vegetables, has anticancer properties in various malignant cancer cells. However, the molecular basis of the anticancer effect remains to be elucidated. In this study, we investigated the cellular mechanisms underlying the induction of cell cycle arrest by apigenin. Our results showed that apigenin at the nonapoptotic induction concentration inhibited cell proliferation and induced cell cycle arrest at the G2/M phase in the MDA-MB-231 breast cancer cell line. Immunoblot analysis indicated that apigenin suppressed the expression of cyclin A, cyclin B, and cyclin-dependent kinase-1 (CDK1), which control the G2-to-M phase transition in the cell cycle. In addition, apigenin upregulated p21WAF1/CIP1 and increased the interaction of p21WAF1/CIP1 with proliferating cell nuclear antigen (PCNA), which inhibits cell cycle progression. Furthermore, apigenin significantly inhibited histone deacetylase (HDAC) activity and induced histone H3 acetylation. The subsequent chromatin immunoprecipitation (ChIP) assay indicated that apigenin increased acetylation of histone H3 in the p21WAF1/CIP1 promoter region, resulting in the increase of p21WAF1/CIP1 transcription. In a tumor xenograft model, apigenin effectively delayed tumor growth. In these apigenin-treated tumors, we also observed reductions in the levels of cyclin A and cyclin B and increases in the levels of p21WAF1/CIP1 and acetylated histone H3. These findings demonstrate for the first time that apigenin can be used in breast cancer prevention and treatment through epigenetic regulation. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 434-444, 2017.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apigenina/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Fase G2/efeitos dos fármacos , Histonas/metabolismo , Acetilação , Animais , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Epigênese Genética/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Histona Desacetilases/análise , Histona Desacetilases/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Quercetin is a plant-derived bioflavonoid with high anticancer activity in various tumors. Herein, the molecular mechanisms by which quercetin exerts its anticancer effects against HL-60 acute myeloid leukemia (AML) cells were investigated. Results showed that quercetin suppressed cell proliferation in the HL-60 cell line in vitro and in vivo. Quercetin-induced G0 /G1 -phase arrest occurred when expressions of cyclin-dependent kinase (CDK)2/4 were inhibited and the CDK inhibitors, p16 and p21, were induced. Moreover, quercetin treatment not only activated proapoptotic signaling like poly (ADP ribose) polymerase (PARP)-1 cleavage and caspase activation but also triggered autophagy events as shown by the increased expression of light chain 3 (LC3)-II, decreased expression of p62, and formation of acidic vesicular organelles. Interestingly, it was found that use of the autophagy inhibitor, 3-methyladenine, significantly enhanced quercetin-mediated apoptotic cell death as analyzed by MTS and DNA fragmentation assays. Moreover, pretreatment of HL-60 cells with the pan-caspase inhibitor, Z-VAD-fmk, dramatically reversed quercetin-mediated apoptotic and autophagic cell death. Although apoptosis and autophagy are two independent cell death pathways, our findings indicated that quercetin can activate caspases to trigger these two pathways, and both pathways played contrary roles in quercetin-mediated HL-60 cell death. In conclusion, besides promoting apoptosis, quercetin also induced cytoprotective autophagy in HL-60 cells, and inhibition of autophagy may be a novel strategy to enhance the anticancer activity of quercetin in AML.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Caspases/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Quercetina/farmacologia , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Adenina/análogos & derivados , Adenina/farmacologia , Clorometilcetonas de Aminoácidos/farmacologia , Inibidores de Caspase/farmacologia , Proliferação de Células/efeitos dos fármacos , Ativação Enzimática , Células HL-60 , Humanos , Poli(ADP-Ribose) Polimerases/metabolismo , Transdução de SinaisRESUMO
Tricetin is a dietary flavonoid with cytostatic properties and antimetastatic activities in various solid tumors. The anticancer effect of tricetin in nonsolid tumors remains unclear. Herein, the molecular mechanisms by which tricetin exerts its anticancer effects on acute myeloid leukemia (AML) cells were investigated. Results showed that tricetin inhibited cell viability in various types of AML cell lines. Tricetin induced morphological features of apoptosis such as chromatin condensation and phosphatidylserine (PS) externalization, and significantly activated proapoptotic signaling including caspase-8, -9, and -3 activation and poly(ADP-ribose) polymerase (PARP) cleavage in HL-60 AML cells. Of note, tricetin-induced cell growth inhibition was dramatically reversed by a pan caspase and caspase-8- and -9-specific inhibitors, suggesting that this compound mainly acts through a caspase-dependent pathway. Moreover, treatment of HL-60 cells with tricetin induced sustained activation of extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK), and inhibition of ERK and JNK by their specific inhibitors respectively promoted and abolished tricetin-induced cell apoptosis. Dichlorofluorescein (DCF) staining showed that intracellular reactive oxygen species (ROS) levels were higher in tricetin-treated HL-60 cells compared to the control group. Moreover, an ROS scavenger, N-acetylcysteine (NAC), reversed tricetin-induced JNK activation and subsequent cell apoptosis. In conclusion, our results indicated that tricetin induced cell death of leukemic HL-60 cells through induction of intracellular oxidative stress following activation of a JNK-mediated apoptosis pathway. A combination of tricetin and an ERK inhibitor may be a better strategy to enhance the anticancer activities of tricetin in AML.
Assuntos
Cromonas/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Acetilcisteína/farmacologia , Apoptose , Caspases/metabolismo , Ativação Enzimática/efeitos dos fármacos , Células HL-60 , HumanosRESUMO
Lipocalin 2 (LCN2), a secreted glycoprotein, is up- or downregulated in different human cancers. At present, the functional role of LCN2 in the progression of oral squamous cell carcinoma (OSCC), which accounts for most head and neck cancers, remains poorly understood, particularly with respect to its involvement in invasion and metastasis. In this study, we observed that LCN2 expression decreased in patients with OSCC and lymph node metastasis compared with that in patients without metastasis. A higher LCN2 expression correlated with the survival of patients with OSCC. Furthermore, LCN2 overexpression in OSCC cells reduced in vitro migration and invasion and in vivo metastasis, whereas its silencing induced an increase in cell motility. Mechanistically, LCN2 inhibited the cell motility of OSCC cells through hypoxia-inducible factor (HIF)-1α-dependent transcriptional inhibition of the carbonic anhydrase IX (CAIX). CAIX overexpression relieved the migration inhibition imposed by LCN2 overexpression in OSCC cells. Moreover, a microRNA (miR) analysis revealed that LCN2 can suppress CAIX expression and cell migration through miR-4505 induction. Examination of tumour tissues from patients with OSCC and OSCC-transplanted mice revealed an inverse correlation between LCN2 and CAIX expression. Furthermore, patients with LCN2(strong)/CAIX(weak) revealed the lowest frequency of lymph node metastasis and the longest survival. Our findings suggest that LCN2 suppresses tumour metastasis by targeting the transcriptional and post-transcriptional regulation of CAIX in OSCC cells. LCN2 overexpression may be a novel OSCC treatment strategy and a useful biomarker for predicting OSCC progression.
Assuntos
Antígenos de Neoplasias/biossíntese , Anidrase Carbônica IX/biossíntese , Carcinoma de Células Escamosas/genética , Lipocalina-2/biossíntese , Neoplasias Bucais/genética , Prognóstico , Adulto , Animais , Antígenos de Neoplasias/genética , Anidrase Carbônica IX/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Lipocalina-2/genética , Metástase Linfática/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologiaRESUMO
Renal cell carcinoma (RCC) is the most lethal of all urological malignancies because of its potent metastasis potential. Melatonin exerts multiple tumor-suppressing activities through antiproliferative, proapoptotic, and anti-angiogenic actions and has been tested in clinical trials. However, the antimetastastic effect of melatonin and its underlying mechanism in RCC are unclear. In this study, we demonstrated that melatonin at the pharmacologic concentration (0.5-2 mm) considerably reduced the migration and invasion of RCC cells (Caki-1 and Achn). Furthermore, we found that melatonin suppressed metastasis of Caki-1 cells in spontaneous and experimental metastasis animal models. Mechanistic investigations revealed that melatonin transcriptionally inhibited MMP-9 by reducing p65- and p52-DNA-binding activities. Moreover, the Akt-mediated JNK1/2 and ERK1/2 signaling pathways were involved in melatonin-regulated MMP-9 transactivation and cell motility. Clinical samples revealed an inverse correlation between melatonin receptor 1A (MTNR1A) and MMP-9 expression in normal kidney and RCC tissues. In addition, a higher survival rate was found in MTNR1A(high) /MMP-9(low) patients than in MTNR1A(low) /MMP-9(high) patients. Overall, our results provide new insights into the role of melatonin-induced molecular regulation in suppressing RCC metastasis and suggest that melatonin has potential therapeutic applications for metastastic RCC.
Assuntos
Carcinoma de Células Renais/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Renais/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Metaloproteinase 9 da Matriz/biossíntese , Melatonina/farmacologia , Subunidade p52 de NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Transcrição RelA/metabolismo , Ativação Transcricional/efeitos dos fármacos , Animais , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Células HL-60 , Humanos , Neoplasias Renais/genética , Neoplasias Renais/patologia , Metaloproteinase 9 da Matriz/genética , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Subunidade p52 de NF-kappa B/genética , Metástase Neoplásica , Proteínas Proto-Oncogênicas c-akt/genética , Fator de Transcrição RelA/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Our previous work demonstrated the epithelial-mesenchymal transition factor, Snail, is a potential marker for predicting the recurrence of localized prostate cancer (PCa). Akt activation is important for Snail stabilization and transcription in PCa. The purpose of this study was to retrospectively investigate the relationship between the phosphorylated level of Akt (p-Akt) in radical prostatectomy (RP) specimens and cancer biochemical recurrence (BCR). Using a tissue microarray and immunohistochemistry, the expression of p-Akt was measured in benign and neoplastic tissues from RP specimens in 53 patients whose cancer was pathologically defined as T2 without positive margins. Herein, we observed that the p-Akt level was higher in PCa than in benign tissues and was significantly associated with the Snail level. A high p-Akt image score (≥8) was significantly correlated with a higher histological Gleason sum, Snail image score, and preoperative prostate-specific antigen (PSA) value. Moreover, the high p-Akt image score and Gleason score sum (≥7) showed similar discriminatory abilities for BCR according to a receiver-operator characteristic curve analysis and were correlated with worse recurrence-free survival according to a log-rank test (p < 0.05). To further determine whether a high p-Akt image score could predict the risk of BCR, a Cox proportional hazard model showed that only a high p-Akt image score (hazard ratio (HR): 3.12, p = 0.05) and a high Gleason score sum (≥7) (HR: 1.18, p = 0.05) but not a high preoperative PSA value (HR: 0.62, p = 0.57) were significantly associated with a higher risk of developing BCR. Our data indicate that, for localized PCa patients after an RP, p-Akt can serve as a potential prognostic marker that improves predictions of BCR-free survival.
Assuntos
Biomarcadores Tumorais/metabolismo , Recidiva Local de Neoplasia/patologia , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fatores de Transcrição da Família Snail/metabolismo , Idoso , Idoso de 80 Anos ou mais , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/cirurgia , Estadiamento de Neoplasias , Prognóstico , Prostatectomia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/cirurgia , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
High-level expression of vascular endothelial growth factor (VEGF)-C is associated with chemoresistance and adverse prognosis in acute myeloid leukemia (AML). Our previous study has found that VEGF-C induces cyclooxygenase-2 (COX-2) expression in AML cell lines and significant correlation of VEGF-C and COX-2 in bone marrow specimens. COX-2 has been reported to mediate the proliferation and drug resistance in several solid tumors. Herein, we demonstrated that the VEGF-C-induced proliferation of AML cells is effectively abolished by the depletion or inhibition of COX-2. The expression of endothelin-1 (ET-1) rapidly increased following treatment with VEGF-C. We found that ET-1 was also involved in the VEGF-C-mediated proliferation of AML cells, and that recombinant ET-1 induced COX-2 mRNA and protein expressions in AML cells. Treatment with the endothelin receptor A (ETRA) antagonist, BQ 123, or ET-1 shRNAs inhibited VEGF-C-induced COX-2 expression. Flow cytometry and immunoblotting revealed that VEGF-C induces S phase accumulation through the inhibition of p27 and the upregulation of cyclin E and cyclin-dependent kinase-2 expressions. The cell-cycle-related effects of VEGF-C were reversed by the depletion of COX-2 or ET-1. The depletion of COX-2 or ET-1 also suppressed VEGF-C-induced increases in the bcl-2/bax ratio and chemoresistance against etoposide and cytosine arabinoside in AML cells. We also demonstrated VEGF-C/ET-1/COX-2 axis-mediated chemoresistance in an AML xenograft mouse model. Our findings suggest that VEGF-C induces COX-2-mediated resistance to chemotherapy through the induction of ET-1 expression. Acting as a key regulator in the VEGF-C/COX-2 axis, ET-1 represents a potential target for ameliorating resistance to chemotherapy in AML patients.
Assuntos
Ciclo-Oxigenase 2/biossíntese , Resistencia a Medicamentos Antineoplásicos , Endotelina-1/metabolismo , Leucemia Mieloide Aguda/enzimologia , Leucemia Mieloide Aguda/patologia , Fator C de Crescimento do Endotélio Vascular/metabolismo , Animais , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Indução Enzimática/efeitos dos fármacos , Humanos , Masculino , Camundongos , Regulação para Cima/efeitos dos fármacos , Fator C de Crescimento do Endotélio Vascular/farmacologiaRESUMO
UNLABELLED: Leukocyte cell-derived chemotoxin 2 (LECT2) has been shown to act as a tumor suppressor in hepatocellular carcinoma (HCC). However, the underlying mechanism has not yet been completely defined. Here, we employ a LECT2-affinity column plus liquid chromatography coupled with tandem mass spectrometry to identify LECT2-binding proteins and found that MET receptor strongly interacted with LECT2 protein. Despite the presence of hepatocyte growth factor, the LECT2 binding causes an antagonistic effect to MET receptor activation through recruitment of protein tyrosine phosphatase 1B. The antagonistic effect of LECT2 on MET activation also mainly contributes to the blockage of vascular invasion and metastasis of HCC. Furthermore, serial deletions and mutations of LECT2 showed that the HxGxD motif is primarily responsible for MET receptor binding and its antagonistic effects. CONCLUSION: These findings reveal a novel, specific inhibitory function of LECT2 in HCC by the direct binding and inactivation of MET, opening a potential avenue for treating MET-related liver cancer.
Assuntos
Carcinoma Hepatocelular/patologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neoplasias Hepáticas/patologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Carcinoma Hepatocelular/metabolismo , Células Hep G2 , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/química , Neoplasias Hepáticas/metabolismo , Invasividade Neoplásica/patologia , Fosforilação/fisiologia , Ligação Proteica/fisiologia , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-met/químicaRESUMO
Quercetin is a plant-derived bioflavonoid that was recently shown to have multiple anticancer activities in various solid tumors. Here, novel molecular mechanisms through which quercetin exerts its anticancer effects in acute myeloid leukemia (AML) cells were investigated. Results from Western blot and flow cytometric assays revealed that quercetin significantly induced caspase-8, caspase-9, and caspase-3 activation, poly ADP-ribose polymerase (PARP) cleavage, and mitochondrial membrane depolarization in HL-60 AML cells. The induction of PARP cleavage by quercetin was also observed in other AML cell lines: THP-1, MV4-11, and U937. Moreover, treatment of HL-60 cells with quercetin induced sustained activation of extracellular signal-regulated kinase (ERK), and inhibition of ERK by an ERK inhibitor significantly abolished quercetin-induced cell apoptosis. MitoSOX red and 2',7'-dichlorofluorescin fluorescence, respectively, showed that mitochondrial superoxide and intracellular peroxide levels were higher in quercetin-treated HL-60 cells compared with the control group. Moreover, both N-acetylcysteine and the superoxide dismutase mimetic, MnTBAP, reversed quercetin-induced intracellular reactive oxygen species production, ERK activation, and subsequent cell death. The in vivo xenograft mice experiments revealed that quercetin significantly reduced tumor growth through inducing intratumoral oxidative stress while activating the ERK pathway and subsequent cell apoptosis in mice with HL-60 tumor xenografts. In conclusions, our results indicated that quercetin induced cell death of HL-60 cells in vitro and in vivo through induction of intracellular oxidative stress following activation of an ERK-mediated apoptosis pathway.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Leucemia Mieloide Aguda/tratamento farmacológico , Mitocôndrias/efeitos dos fármacos , Quercetina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Antioxidantes/farmacologia , Proteínas Reguladoras de Apoptose/metabolismo , Ativação Enzimática , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Células HL-60 , Humanos , Leucemia Mieloide Aguda/enzimologia , Leucemia Mieloide Aguda/patologia , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos Nus , Camundongos SCID , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Oxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Nobiletin, a compound isolated from citrus fruits, is a polymethoxylated flavone derivative that was shown to have anti-inflammatory and anticancer activities in various solid tumors. The anticancer effect of nobiletin on nonsolid tumor remains unclear. Herein, the molecular mechanisms by which nobiletin exerts its anticancer effects on acute myeloid leukemia (AML) cells were investigated. The results showed that nobiletin suppressed cell proliferation in various types of AML cell lines. Moreover, nobiletin induced cell-cycle arrest of HL-60 AML cells at the G0/G1 phase by suppressing extracellular signal-regulated kinase (ERK) activity. Furthermore, nobiletin effectively induced apoptosis of HL-60 cells through caspase-8, caspase-9, and caspases-3 activation concomitantly with a marked induction of p38 mitogen-activated protein kinase (MAPK) activation, but without affecting expression levels of Bcl-2, Bax, or Bid. Taken together, our results suggest that nobiletin inhibited HL-60 cell proliferation through inducing cell-cycle arrest and apoptosis and could serve as a potential additional chemotherapeutic agent for treating AML.
Assuntos
Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 8/metabolismo , Caspase 9/metabolismo , Flavonas/farmacologia , Leucemia Mieloide Aguda/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Transdução de Sinais/efeitos dos fármacos , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Apoptose/genética , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Leucemia Mieloide Aguda/genéticaRESUMO
α-Solanine, a naturally occurring steroidal glycoalkaloid found in nightshade (Solanum nigrum Linn.), was found to inhibit proliferation and induce apoptosis of tumor cells. However, the mechanism involved in suppression of cancer cell metastasis by α-solanine remains unclear. This study investigates the suppression mechanism of α-solanine on motility of the human prostate cancer cell PC-3. Results show that α-solanine reduces the viability of PC-3 cells. When treated with non-toxic doses of α-solanine, cell invasion is markedly suppressed by α-solanine. α-Solanine also significantly elevates epithelial marker E-cadherin expression, while it concomitantly decreases mesenchymal marker vimentin expression, suggesting it suppresses epithelial-mesenchymal transition (EMT). α-Solanine reduces the mRNA level of matrix metalloproteinase-2 (MMP-2), MMP-9 and extracellular inducer of matrix metalloproteinase (EMMPRIN), but increases the expression of reversion-inducing cysteine-rich protein with kazal motifs (RECK), and tissue inhibitor of metalloproteinase-1 (TIMP-1) and TIMP-2. Immunoblotting assays indicate α-solanine is effective in suppressing the phosphorylation of phosphatidylinositide-3 kinase (PI3K), Akt and ERK. Moreover, α-solanine downregulates oncogenic microRNA-21 (miR-21) and upregulates tumor suppressor miR-138 expression. Taken together, the results suggest that inhibition of PC-3 cell invasion by α-solanine may be, at least in part, through blocking EMT and MMPs expression. α-Solanine also reduces ERK and PI3K/Akt signaling pathways and regulates expression of miR-21 and miR-138. These findings suggest an attractive therapeutic potential of α-solanine for suppressing invasion of prostate cancer cell.
Assuntos
Transição Epitelial-Mesenquimal/efeitos dos fármacos , Metaloproteinase 2 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/biossíntese , Neoplasias da Próstata/tratamento farmacológico , Solanina/administração & dosagem , Caderinas/biossíntese , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Transdução de Sinais/efeitos dos fármacos , Solanum nigrum/química , Inibidor Tecidual de Metaloproteinase-1/biossíntese , Inibidor Tecidual de Metaloproteinase-2/biossínteseRESUMO
Neuroendocrine prostate cancer (PCa) (NEPC), an aggressive subtype that is associated with poor prognosis, may arise after androgen deprivation therapy (ADT). We investigated the molecular mechanisms by which ADT induces neuroendocrine differentiation in advanced PCa. We found that transmembrane protein 1 (MCTP1), which has putative Ca2+ sensing function and multiple Ca2+-binding C2 domains, was abundant in samples from patients with advanced PCa. MCTP1 was associated with the expression of the EMT-associated transcription factors ZBTB46, FOXA2, and HIF1A. The increased abundance of MCTP1 promoted PC3 prostate cancer cell migration and neuroendocrine differentiation and was associated with SNAI1-dependent EMT in C4-2 PCa cells after ADT. ZBTB46 interacted with FOXA2 and HIF1A and increased the abundance of MCTP1 in a hypoxia-dependent manner. MCTP1 stimulated Ca2+ signaling and AKT activation to promote EMT and neuroendocrine differentiation by increasing the SNAI1-dependent expression of EMT and neuroendocrine markers, effects that were blocked by knockdown of MCTP1. These data suggest an oncogenic role for MCTP1 in the maintenance of a rare and aggressive prostate cancer subtype through its response to Ca2+ and suggest its potential as a therapeutic target.