RESUMO
Exosomes are extracellular vesicles generated by all cells and they carry nucleic acids, proteins, lipids, and metabolites. They mediate the exchange of substances between cells,thereby affecting biological properties and activities of recipient cells. In this review, we briefly discuss the composition of exocomes and exosome isolation. We also review the clinical applications of exosomes in cancer biology as well as strategies in exosome-mediated targeted drug delivery systems. Finally, the application of exosomes in the context of cancer therapeutics both in practice and literature are discussed.
Assuntos
Exossomos , Neoplasias , Exossomos/metabolismo , Humanos , Neoplasias/terapia , Sistemas de Liberação de Medicamentos/métodos , Ensaios Clínicos como AssuntoRESUMO
RNA therapeutics has advanced into the third milestone in pharmaceutical drug development, following chemical and protein therapeutics. RNA itself can serve as therapeutics, carriers, regulators, or substrates in drug development. Due to RNA's motile, dynamic, and deformable properties, RNA nanoparticles have demonstrated spontaneous targeting and accumulation in cancer vasculature and fast excretion through the kidney glomerulus to urine to prevent possible interactions with healthy organs. Furthermore, the negatively charged phosphate backbone of RNA results in general repulsion from negatively charged lipid cell membranes for further avoidance of vital organs. Thus, RNA nanoparticles can spontaneously enrich tumor vasculature and efficiently enter tumor cells via specific targeting, while those not entering the tumor tissue will clear from the body quickly. These favorable parameters have led to the expectation that RNA has low or little toxicity. RNA nanoparticles have been well characterized for their anticancer efficacy; however, little detail on RNA nanoparticle pathology and safety is known. Here, we report the in vitro and in vivo assessment of the pathology and safety aspects of different RNA nanoparticles including RNA three-way junction (3WJ) harboring 2'-F modified pyrimidine, folic acid, and Survivin siRNA, as well as the RNA four-way junction (4WJ) harboring 2'-F modified pyrimidine and 24 copies of SN38. Both animal models and patient serum were investigated. In vitro studies include hemolysis, platelet aggregation, complement activation, plasma coagulation, and interferon induction. In vivo studies include hematoxylin and eosin (H&E) staining, hematological and biochemical analysis as the serum profiling, and animal organ weight study. No significant toxicity, side effect, or immune responses were detected during the extensive safety evaluations of RNA nanoparticles. These results further complement previous cancer inhibition studies and demonstrate RNA nanoparticles as an effective and safe drug delivery vehicle for future clinical translations.
Assuntos
Nanopartículas , Neoplasias , Animais , Humanos , RNA Interferente Pequeno/genética , Sistemas de Liberação de Medicamentos , Neoplasias/metabolismo , Nanopartículas/química , PirimidinasRESUMO
RNA nanotechnology is the bottom-up self-assembly of nanometer-scale architectures, resembling LEGOs, composed mainly of RNA. The ideal building material should be (1) versatile and controllable in shape and stoichiometry, (2) spontaneously self-assemble, and (3) thermodynamically, chemically, and enzymatically stable with a long shelf life. RNA building blocks exhibit each of the above. RNA is a polynucleic acid, making it a polymer, and its negative-charge prevents nonspecific binding to negatively charged cell membranes. The thermostability makes it suitable for logic gates, resistive memory, sensor set-ups, and NEM devices. RNA can be designed and manipulated with a level of simplicity of DNA while displaying versatile structure and enzyme activity of proteins. RNA can fold into single-stranded loops or bulges to serve as mounting dovetails for intermolecular or domain interactions without external linking dowels. RNA nanoparticles display rubber- and amoeba-like properties and are stretchable and shrinkable through multiple repeats, leading to enhanced tumor targeting and fast renal excretion to reduce toxicities. It was predicted in 2014 that RNA would be the third milestone in pharmaceutical drug development. The recent approval of several RNA drugs and COVID-19 mRNA vaccines by FDA suggests that this milestone is being realized. Here, we review the unique properties of RNA nanotechnology, summarize its recent advancements, describe its distinct attributes inside or outside the body and discuss potential applications in nanotechnology, medicine, and material science.
Assuntos
Nanomedicina/métodos , Neoplasias/tratamento farmacológico , Estabilidade de RNA , RNA/química , Animais , Humanos , Terapia de Alvo Molecular , TermodinâmicaRESUMO
The regulation of RagA(GTP) is important for amino-acid-induced mTORC1 activation. Although GATOR1 complex has been identified as a negative regulator for mTORC1 by hydrolyzing RagA(GTP), how GATOR1 is recruited to RagA to attenuate mTORC1 signaling remains unclear. Moreover, how mTORC1 signaling is terminated upon amino acid stimulation is also unknown. We show that the recruitment of GATOR1 to RagA is induced by amino acids in an mTORC1-dependent manner. Skp2 E3 ligase drives K63-linked ubiquitination of RagA, which facilitates GATOR1 recruitment and RagA(GTP) hydrolysis, thereby providing a negative feedback loop to attenuate mTORC1 lysosomal recruitment and prevent mTORC1 hyperactivation. We further demonstrate that Skp2 promotes autophagy but inhibits cell size and cilia growth through RagA ubiquitination and mTORC1 inhibition. We thereby propose a negative feedback whereby Skp2-mediated RagA ubiquitination recruits GATOR1 to restrict mTORC1 signaling upon sustained amino acid stimulation, which serves a critical mechanism to maintain proper cellular functions.
Assuntos
Aminoácidos/farmacologia , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Complexos Multiproteicos/metabolismo , Proteínas Quinases Associadas a Fase S/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Autofagia/genética , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , Retroalimentação Fisiológica/efeitos dos fármacos , Guanosina Trifosfato/metabolismo , Células HEK293 , Humanos , Immunoblotting , Lisina/metabolismo , Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Knockout , Microscopia Confocal , Modelos Biológicos , Células NIH 3T3 , Ligação Proteica/efeitos dos fármacos , Interferência de RNA , Proteínas Quinases Associadas a Fase S/genética , Ubiquitinação/efeitos dos fármacosRESUMO
Activating transcription factor 3 (ATF3) is a stress-induced transcription factor and a familiar neuronal marker for nerve injury. This factor has been shown to protect neurons from hypoxic insult in vitro by suppressing carboxyl-terminal modulator protein (CTMP) transcription, and indirectly activating the anti-apoptotic Akt/PKB cascade. Despite prior studies in vitro, whether this neuroprotective pathway also exists in the brain in vivo after ischemic insult remains to be determined. In the present study, we showed a rapid and marked induction of ATF3 mRNA throughout ischemia-reperfusion in a middle cerebral artery (MCA) occlusion model. Although the level of CTMP mRNA was quickly induced upon ischemia, its level showed only a mild increase after reperfusion. With the gain-of-function approach, both pre- and post-ischemic administration of Ad-ATF3 ameliorated brain infarct and neurological deficits. Whereas, with the loss-of-function approach, ATF3 knockout (KO) mice showed bigger infarct and worse functional outcome after ischemia. In addition, these congenital defects were rescued upon reintroducing ATF3 to the brain of KO mice. ATF3 overexpression led to a lower level of CTMP and a higher level of p-Akt(473) in the ischemic brain. On the contrary, ATF3 KO resulted in upregulation of CTMP and downregulation of p-Akt(473) instead. Furthermore, post-ischemic CTMP siRNA knockdown led to smaller infarct and better behaviors. CTMP siRNA knockdown increased the level of p-Akt(473), but did not alter the ATF3 level in the ischemic brain, upholding the ATF3âCTMP signal cascade. In summary, our proof-of-principle experiments support the existence of neuroprotective ATF3âCTMP signal cascade regulating the ischemic brain. Furthermore, these results suggest the therapeutic potential for both ATF3 overexpression and CTMP knockdown for stroke treatment.
Assuntos
Isquemia Encefálica , Proteínas Proto-Oncogênicas c-akt , Camundongos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator 3 Ativador da Transcrição/genética , Fator 3 Ativador da Transcrição/metabolismo , Proteínas de Transporte/metabolismo , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Camundongos Knockout , Infarto Encefálico/genética , RNA Interferente Pequeno/genética , Infarto Cerebral , Palmitoil-CoA Hidrolase/metabolismoRESUMO
Currently, computed tomography and conventional X-ray radiography usually generate a micro-artifact around metal implants. This metal artifact frequently causes false positive or negative diagnoses of bone maturation or pathological peri-implantitis around implants. In an attempt to repair the artifacts, a highly specific nanoprobe, an osteogenic biomarker, and nano-Au-Pamidronate were designed to monitor the osteogenesis. In total, 12 Sprague Dawley rats were included in the study and could be chategorized in 3 groups: 4 rats in the X-ray and CT group, 4 rats in the NIRF group, and 4 rats in the sham group. A titanium alloy screw was implanted in the anterior hard palate. The X-ray, CT, and NIRF images were taken 28 days after implantation. The X-ray showed that the tissue surrounded the implant tightly; however, a gap of metal artifacts was noted around the interface between dental implants and palatal bone. Compared to the CT image, a fluorescence image was noted around the implant site in the NIRF group. Furthermore, the histological implant-bone tissue also exhibited a significant NIRF signal. In conclusion, this novel NIRF molecular imaging system precisely identifies the image loss caused by metal artifacts and can be applied to monitoring bone maturation around orthopedic implants. In addition, by observing the new bone formation, a new principle and timetable for an implant osseointegrated with bone can be established and a new type of implant fixture or surface treatment can be evaluated using this system.
Assuntos
Implantes Dentários , Osseointegração , Ratos , Animais , Osteogênese , Ratos Sprague-Dawley , Maxila , Próteses e Implantes , TitânioRESUMO
BACKGROUND/PURPOSE: Previously we had identified concurrent genes, which highlighted the interplay between copy number variation (CNV) and differential gene expression (GE) for Han Chinese breast cancers. The merit of the approach is to discovery biomarkers not identifiable by conventional GE only data, for which phenotype-correlation or gene variability is the criteria of gene selection. MATERIALS AND METHODS: Thirty-one comparative genomic hybridization (CGH) and 83 GE microarrays were performed, with 29 breast cancers assayed from both platforms. Potential targets were revealed by Genomic Identification of Significant Targets in Cancer (GISTIC) from CGH arrays. Concurrent genes and genes with significant GISTIC scores were used to derive the extended concurrent genes signature, which was consensus from leading edge analysis across all studies and a supervised partial least square (PLS) regression predictive model of disease-free survival was constructed. RESULTS: There were 1584 concurrent genes from 29 samples with both CGH and GE microarrays. Enriched concurrent genes sets for disease-free survival were identified independently from 83 GE arrays and another one with Han Chinese origin as well as three studies of Western origin. For five studies with disease-free survival follow up, prognostic discrepancy was observed between predicted high-risk and low-risk group patients. CONCLUSION: We concluded that through parallel analyses of CGH and GE microarrays, the proposed extended concurrent gene expression signature can identify biomarkers with prognostic values.
Assuntos
Variações do Número de Cópias de DNA , Neoplasias , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Hibridização Genômica Comparativa , Intervalo Livre de Doença , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , PrognósticoRESUMO
The treatment of pancreatic ductal adenocarcinoma (PDAC) remains a huge challenge, because pro-survival signaling pathways-such as the receptor for advanced glycation end products (RAGE)/signal transducer and activator of transcription 3 (STAT3) pathway-are overexpressed in PDAC cells. Moreover, PDAC cells are highly resistant to chemotherapeutic agents because of autophagy induction. Therefore, autophagy and its modulated signaling pathways are attractive targets for developing novel therapeutic strategies for PDAC. Pterostilbene is a stilbenoid chemically related to resveratrol, and has potential for the treatment of cancers. Accordingly, we investigated whether the autophagy inhibitor chloroquine could potentiate the anticancer effect of pterostilbene in the PDAC cell lines MIA PaCa-2 and BxPC-3, as well as in an orthotopic animal model. The results indicated that pterostilbene combined with chloroquine significantly inhibited autophagy, decreased cell viability, and sensitized the cells to pterostilbene-induced apoptosis via downregulation of the RAGE/STAT3 and protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathways in PDAC cells. The results of the orthotopic animal model showed that pterostilbene combined with chloroquine significantly inhibited pancreatic cancer growth, delayed tumor quadrupling times, and inhibited autophagy and STAT3 in pancreatic tumors. In summary, the present study suggested the novel therapeutic strategy of pterostilbene combined with chloroquine against the growth of pancreatic ductal adenocarcinoma by inhibiting autophagy and downregulating the RAGE/STAT3 signaling pathways.
Assuntos
Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Carcinoma Ductal Pancreático/tratamento farmacológico , Cloroquina/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Estilbenos/farmacologia , Antígenos de Neoplasias/metabolismo , Antineoplásicos/química , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cloroquina/química , Regulação para Baixo/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Estilbenos/químicaRESUMO
The microenvironment for tumor growth and developing metastasis should be essential. This study demonstrated that the hyaluronic acid synthase 3 (HAS3) protein and its enzymatic product hyaluronic acid (HA) encompassed in the subcutaneous extracellular matrix can attenuate the invasion of human breast tumor cells. Decreased HA levels in subcutaneous Has3-KO mouse tissues promoted orthotopic breast cancer (E0771) cell-derived allograft tumor growth. MDA-MB-231 cells premixed with higher concentration HA attenuate tumor growth in xenografted nude mice. Human patient-derived xenotransplantation (PDX) experiments found that HA selected the highly migratory breast cancer cells with CD44 expression accumulated in the tumor/stroma junction. In conclusion, HAS3 and HA were detected in the stroma breast tissues at a high level attenuates effects for induced breast cancer cell death, and inhibit the cancer cells invasion at the initial stage. However, the highly migratory cancer cells were resistant to the HA-mediated effects with unknown mechanisms.
Assuntos
Neoplasias da Mama/metabolismo , Hialuronan Sintases/metabolismo , Tecido Parenquimatoso/metabolismo , Animais , Neoplasias da Mama/patologia , Feminino , Humanos , Hialuronan Sintases/deficiência , Hialuronan Sintases/genética , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Tecido Parenquimatoso/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Células Tumorais CultivadasRESUMO
The DNA primase polypeptide 1 (PRIM1) is responsible for synthesizing small RNA primers for Okazaki fragments generated during discontinuous DNA replication. PRIM1 mRNA expression levels in breast tumor samples were detected by real-time PCR analysis. Xenografted tumor model was established to study the carcinogenic role of PRIM1 and its potential therapeutic applications. The average PRIM1 mRNA (copy number × 103 /µg) expression was 4.7-fold higher in tumors than in normal tissue (*p = 0.005, n = 254). PRIM1 was detected preferentially at a higher level (>40-fold) in poorly differentiated tumor tissues (n = 46) compared with more highly differentiated tumors tissues (n = 10) (*p = 0.005). Poor overall survival rate was correlated to the estrogen receptor positive (ER+, n = 20) patients with higher PRIM1 expression when compare to the ER- (n = 10) patients (Chi Square test, p = 0.03). Stable expression of PRIM1-siRNA in the ER+ BT-474 cells-xenograft tumors significantly reduced tumor volume in SCID mice (*p = 0.005). The anti-tumoral effects of inotilone isolated from Phellinus linteus was tested and had significant effects on the inhibition of PRIM1 protein expression in ER+ breast cancer cells. In vivo study was performed by administering inotilone (10 mg/kg, twice a week for 6 weeks), which resulted in significantly reduced BT-474-xenografted tumor growth volume compared with control (n =5 per group, *p < 0.05). This study provides evidences for the prognostic effects of PRIM1 with poor overall survival rate in the ER+ patients and will be valuable to test for therapeutic purpose.
Assuntos
Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , DNA Primase/metabolismo , Animais , Neoplasias da Mama/genética , Linhagem Celular Tumoral , DNA Primase/biossíntese , DNA Primase/genética , Feminino , Furanos/farmacologia , Pontos de Checagem da Fase G2 do Ciclo Celular , Xenoenxertos , Humanos , Células MCF-7 , Macrolídeos/farmacologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptores de Estrogênio/metabolismoRESUMO
Failure to eradicate hematologic cancer stem cells (hCSCs) associated with resistance to tyrosine kinase inhibitors such as imatinib mesylate (IM) in chronic myeloid leukemia (CML) patients is a clinical challenge that highlights the need for discovering and developing therapeutic strategies that target and eliminate these hCSCs. Herein, we document the essential role of the interplay between histone deacetylases (HDACs), the polycomb group proteins, pluripotency transcription factors and the cell cycle machinery in the viability, oncogenicity and therapy evasion of IM-resistant CD34+/CD38- CML stem cells (CML-SCs). Using the proteotranscriptomic analyses of wild type (WT), CD34+/CD38+ and CD34+/CD38- K562 or KU812 cells, we showed that CD34+/CD38- SC-enriched cells expressed significantly higher levels of CD44, CD133, SOX2, Nanog, OCT4, and c-Myc mRNA and/or protein, compared to the WT or CD34+/CD38+ cells. This overexpression of stemness factors in the CD34+/CD38- cells positively correlates with enhanced expression of HDACs 1-6, cyclins D1/D3, CDK 2, 4 and 6, while inversely correlating with p18, p21 and p27. Enhanced co-expression of MDR1, survivin, and Bcl-2 proteins, supposedly involved in IM-resistance and CML-SC survival, was detected in both CD34+/CD38- and CD34+/CD38+ cells. Importantly, we demonstrate that in synergism with IM, SAHA reverses the tumor-promoting proteotranscriptomic profile noted above and elicits marked inhibition of the CML-SCs by up-regulating hsa-miR-196a expression. This hsa-miR-196a-mediated SC-limiting effect of SAHA is dose-dependent, low-dosed, cell cycle-modulating and accompanied by leukemic SC apoptosis. Interestingly, this anti-SC therapeutic activity of SAHA in vitro was reproduced in vivo using the NOD-SCID mice models.
Assuntos
Proliferação de Células/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , MicroRNAs/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-abl/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Proteínas de Fusão bcr-abl/efeitos dos fármacos , Proteínas de Fusão bcr-abl/genética , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Mesilato de Imatinib/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Camundongos Endogâmicos BALB C , Células-Tronco Neoplásicas/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologiaRESUMO
BACKGROUND: Apiole was isolated from the leaves of various plants and vegetables and has been demonstrated to inhibit human colon cancer cell (COLO 205 cells) growth through induction of G0/G1 cell cycle arrest and apoptotic cell death. This study further explored the antitumor effects of apiole derivatives AP-02, 04, and 05 in COLO 205 cancer cells. METHODS: Human breast (MDA-MB-231, ZR75), lung (A549, PE089), colon (COLO 205, HT 29), and hepatocellular (Hep G2, Hep 3B) cancer cells were treated with apiole and its derivatives in a dose-dependent manner. Flow cytometry analysis was subsequently performed to determine the mechanism of AP-02-induced G0/G1 cell cycle arrest. The in vivo antitumor effect of AP-02 (1 and 5 mg/kg, administered twice per week) was examined by treating athymic nude mice bearing COLO 205 tumor xenografts. The molecular mechanisms of AP-02-induced antitumor effects were determined using western blot analysis. RESULTS: AP-02 was the most effective compound, especially for inhibition of COLO 205 colon cancer cell growth. The cytotoxicity of AP-02 in normal colon epithelial (FHC) cells was significantly lower than that in other normal cells derived from the breast, lung or liver. Flow cytometry analysis indicated that AP-02-induced G0/G1 cell cycle arrest in COLO 205 cells but not in HT 29 cells (< 5 µM for 24 h, **p < 0.01). Tumor growth volume was also significantly inhibited in AP-02 (> 1 mg/kg)-treated athymic nude mice bearing COLO 205 tumor xenografts compared to control mice (*p < 0.05). Furthermore, G0/G1 phase regulatory proteins (p53 and p21/Cip1) and an invasion suppressor protein (E-cadherin) were significantly upregulated, while cyclin D1 was significantly downregulated, in AP-02-treated tumor tissues compared to the control group (> 1 mg/kg, *p < 0.05). CONCLUSIONS: Our results provide in vitro and in vivo molecular evidence of AP-02-induced anti-proliferative effects on colon cancer, indicating that this compound might have potential clinical applications.
Assuntos
Antineoplásicos/administração & dosagem , Neoplasias do Colo/tratamento farmacológico , Dioxóis/administração & dosagem , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Petroselinum/química , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Neoplasias do Colo/fisiopatologia , Ciclina D1/genética , Ciclina D1/metabolismo , Dioxóis/efeitos adversos , Dioxóis/química , Feminino , Humanos , Camundongos , Camundongos Nus , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Breast cancer (BC) is the most common cancer affecting women worldwide and has been associated with active tobacco smoking. Low levels of nicotine (Nic) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), have been detected in cases of second-hand smoke (SHS). However, the correlation between SHS and BC risk remains controversial. In this study, we investigated whether the physiological SHS achievable dose of Nic and tobacco specific nitrosamine, NNK act together to induce breast carcinogenesis using an in vitro breast cell carcinogenesis model. Immortalized non-tumorigenic breast epithelial cell line, HBL-100 used for a time-course assay, was exposed to very low levels of either Nic or NNK, or both. The time-course assay consisted of 23 cycles of nitrosamines treatment. In each cycle, HBL-100 cells were exposed to 1pM of Nic and/or 100 femtM of NNK for 48 hours. Cells were passaged every 3 days and harvested after 10, 15, and 23 cycles. Our results demonstrated that the tumorigenicity of HBL-100, defined by soft agar colony forming, proliferation, migration and invasion abilities, was enhanced by co-exposure to physiologically SHS achievable doses of Nic and NNK. In addition, α9-nAChR signaling activation, which plays an important role in cellular proliferation and cell survival, was also observed. Importantly, an increase in stemness properties including the prevalence of CD44+/CD24- cells, increase Nanog expression and mammosphere-forming ability were also observed. Our results indicate that chronic and long term exposure to environmental tobacco smoke, may induce breast cell carcinogenesis even at extremely low doses.
Assuntos
Neoplasias da Mama/induzido quimicamente , Transformação Celular Neoplásica/efeitos dos fármacos , Glândulas Mamárias Humanas/efeitos dos fármacos , Nicotina/toxicidade , Nitrosaminas/toxicidade , Acetilcolina/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinógenos/toxicidade , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , Feminino , Humanos , Glândulas Mamárias Humanas/patologia , Glândulas Mamárias Humanas/fisiologia , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fatores de Tempo , Testes de Toxicidade CrônicaRESUMO
PURPOSE: Glutathione S-transferase mu 3 (GSTM3) is an enzyme involving in the detoxification of electrophilic compounds by conjugation with glutathione. Higher GSTM3 mRNA levels were reported in patients with ERα-positive breast cancer who received only tamoxifen therapy after surgery. Thus, this study aimed to clarify the oncogenic characteristics of GSTM3 in breast cancer and the mechanism of tamoxifen resistance. METHODS: GSTM3 expression in human breast tumour tissues (n = 227) was analysed by RT-PCR and quantitative PCR. Western blot, promoter activity assays, and chromatin immunoprecipitation (ChIP) assays were used to investigate the mechanism of GSTM3 gene regulation. Hydrogen peroxide (H2O2)-induced cytotoxicity in breast cancer cells was detected by MTT assays and flow cytometry. The oncogenic characteristics of GSTM3 in MCF-7 cells were examined by siRNA knockdown in soft agar assays and a xenograft animal model. RESULTS: GSTM3 mRNA was highly expressed in ER- and HER2-positive breast cancers. Moreover, patients who received adjuvant Herceptin had increased GSTM3 mRNA levels in tumour tissue. Oestrogen-activated GSTM3 gene expression through ERα-mediated recruitment of SP1, EP300, and AP-1 complexes. GSTM3-silenced MCF-7 cells were more sensitive to H2O2, with significantly inhibited proliferation and colony formation abilities. Tamoxifen-resistant (Tam-R) cells lacking GSTM3 showed enhanced sensitivity to H2O2, but this result was contrary to that obtained after short-term tamoxifen exposure. The animal model suggested that GSTM3 silencing might suppress the tumourigenic ability of MCF-7 cells and increase tumour cell apoptosis. CONCLUSIONS: ROS production is one mechanism by which cancer drugs kill tumour cells, and according to our evidence, GSTM3 may play an important role in preventing breast cancer treatment-induced cellular cytotoxicity.
Assuntos
Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Receptor alfa de Estrogênio/genética , Glutationa Transferase/genética , Animais , Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Estrogênios/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Peróxido de Hidrogênio/toxicidade , Células MCF-7 , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Receptor ErbB-2/genética , Transdução de Sinais/efeitos dos fármacos , Tamoxifeno/farmacologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Accumulated evidence indicates that the incidence of early-onset breast cancer has rapidly increased in Taiwan and other Asian compared to Western countries. The mismatch repair (MMR) pathway might be one of the crucial mechanisms of predisposition to early breast cancer. In this study, we explored whether MMR gene polymorphisms contribute to the risk of breast cancer in young women. METHODS: This was a 2-stage case-control study including 737 cases and 719 controls. After eight single nucleotide polymorphisms (SNPs) were genotyped in MMR pathway genes in the stage I study, a promising SNP, MSH2 rs2303425, was selected for validation in the stage II study. A luciferase reporter assay was used to evaluate the transcriptional activity of MSH2. RESULTS: Logistic regression analysis showed that individuals with the MSH2 rs2303425 C/C genotype had a significantly increased risk of breast cancer compared to those with the T/T genotype (adjusted odds ratio 2.0; 95 % confidence interval 1.1-3.8), particularly in early-onset breast cancer patients with the luminal A subtype. The luciferase assay in three cell lines indicated that the MSH2 rs2303425 T/C substitution decreased MSH2 expression, which is consistent with the finding of an association study. CONCLUSIONS: A common variant SNP in MSH2 may contribute to the susceptibility to early-onset breast cancer functionally, particularly for the luminal A subtype.
Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proteína 2 Homóloga a MutS/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/epidemiologia , Estudos de Casos e Controles , Feminino , Seguimentos , Predisposição Genética para Doença , Genótipo , Humanos , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Taiwan/epidemiologia , Adulto JovemRESUMO
Previous studies indicated that smoking exposure is associated with an increased risk of breast cancer, and α9-nicotine acetylcholine receptors (α9-nAChRs) are involved in breast tumorigenesis. However, no studies have explored the joint effect of α9-nAChRs (CHRNA9) genes and cigarette smoking exposure on breast cancer risk. A case-control study was conducted on 737 breast cancer patients and 719 age-matched healthy controls. Three single-nucleotide polymorphisms (SNPs) of CHRNA9 located in the promoter region were genotyped and compared between cases and controls to identify those SNPs associated with breast cancer susceptibility. A dual-luciferase reporter assay was used to analyze the promoter activities of these SNPs of the CHRNA9 gene. After a Bonferroni correction, the G allele of the CHRNA9 rs7329797 SNP was significantly associated with an increased risk of developing breast cancer compared with A/A genotype carriers (odds ratio, 1.8; 95% confidence interval, 1.2-2.6). A multiplicative interaction between passive smoking exposure and the CHRNA9 rs73229797 SNP on the risk of breast malignancy was observed. A functional assay further showed that rs73229797 was associated with increased promoter activity of the CHRNA9 gene. Our findings support a significant interaction effect existing between the CHRNA9 gene and smoking exposure on the risk of breast cancer development.
Assuntos
Neoplasias da Mama/genética , Estudos de Associação Genética , Receptores Nicotínicos/genética , Fumar/genética , Adulto , Idoso , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Feminino , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Fatores de Risco , Fumar/efeitos adversos , TaiwanRESUMO
BACKGROUND: Vascular endothelial growth factor-C (VEGF-C) plays an important role during cancer progression and metastasis through activation of VEGF receptors. However, the role of VEGF-C in esophageal squamous cell carcinoma (ESCC) remains unclear. METHODS: The expression of VEGF-C in advanced stages of esophageal cancer was examined by immunohistochemistry and its expression was correlated with the protein level of cortactin (CTTN) by Western blot. Knockdown and overexpression of the CTTN protein were respectively performed to investigate the effects on VEGF-C-enhanced ESCC migration/invasion by in vitro transwell assay, cell tracing assay, and tumor growth/experimental metastasis in animal models. RESULTS: The expression of VEGF-C was positively correlated with tumor status and poor clinical prognosis in patient with esophageal cancer. VEGF-C-upregulated CTTN expression contributed the migration/invasive abilities of ESCC cell lines through Src-mediated downregulation of miR-326. Moreover, knockdown of CTTN expression significantly abolished VEGF-C-induced tumor growth and experimental lung metastasis in vivo. CONCLUSIONS: Upregulation of CTTN is critical for VEGF-C-mediated tumor growth and metastasis of ESCC. These finding suggest that VEGF-C upregulated CTTN expression through Src-mediated downregulation of miR-326. CTTN may be a crucial mediator of VEGF-C-involved ESCC metastasis, which provides a potential target for diagnosis and individualized treatment in clinical practice.
Assuntos
Carcinoma de Células Escamosas/química , Carcinoma de Células Escamosas/genética , Cortactina/análise , Cortactina/genética , Neoplasias Esofágicas/química , Neoplasias Esofágicas/genética , Neoplasias Pulmonares/genética , Fator C de Crescimento do Endotélio Vascular/análise , Animais , Carcinoma de Células Escamosas/secundário , Linhagem Celular Tumoral , Movimento Celular , Rastreamento de Células , Cortactina/metabolismo , Regulação para Baixo , Neoplasias Esofágicas/patologia , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Pulmonares/secundário , Camundongos SCID , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/genética , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Transdução de Sinais/genética , Transfecção , Regulação para Cima , Fator C de Crescimento do Endotélio Vascular/metabolismoRESUMO
Metastasis is the most life-threatening complication in all cancers. The chemokine receptor 4 (CXCR4) is expressed at high levels in many breast-cancer tumors and may modulate metastasis. We compared the time-to-metastasis and the sites of metastasis between breast-cancer tumors expressing CXCR4 at high or low levels. We enrolled 191 early breast cancer patients in our study. The expression of CXCR4 was evaluated using immunohistochemical staining, and the patients were divided into low-level (CXCR4-) and high-level (CXCR4+) CXCR4 expression groups. Associations between the patients' level of CXCR4 expression and their basic clinical characteristics, time-to-metastasis, and metastatic sites were examined using a Cox proportional-hazards regression model. A total of 107 CXCR4+ patients (56 %) were identified. No statistical differences were evident in basic characteristics between the CXCR4+ and CXCR4- groups. The CXCR4+ group had a higher incidence of distant metastasis during the first year (10.3 % versus 1.1 %, P = 0.009) and shorter event-free survival (17.43 months versus 27.5 months, P = 0.026) than those of the CXCR4- group. The CXCR4+ group also had a higher incidence of bone metastasis (P = 0.008) than the CXCR4- group. No significant difference in metastasis sites in other organs was observed between the two groups. A high level of CXCR4 expression in breast cancer is associated with early distant and bone metastases. The CXCR4+ phenotype may be a useful predictor for the prevention of early treatment failure and bone metastasis in breast cancer patients. This retrospective study shows that a high expression of CXCR4 in breast cancer is associated with earlier distant metastasis and bone metastasis in breast cancer.
Assuntos
Neoplasias da Mama/genética , Estudos de Associação Genética , Receptores CXCR4/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/secundário , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Feminino , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos ProporcionaisRESUMO
The field of RNA therapeutics has been emerging as the third milestone in pharmaceutical drug development. RNA nanoparticles have displayed motile and deformable properties to allow for high tumor accumulation with undetectable healthy organ accumulation. Therefore, RNA nanoparticles have the potential to serve as potent drug delivery vehicles with strong anti-cancer responses. Herein, we report the physicochemical basis for the rational design of a branched RNA four-way junction (4WJ) nanoparticle that results in advantageous high-thermostability and -drug payload for cancer therapy, including metastatic tumors in the lung. The 4WJ nanostructure displayed versatility through functionalization with an anti-cancer chemical drug, SN38, for the treatment of two different cancer models including colorectal cancer xenograft and orthotopic lung metastases of colon cancer. The resulting 4WJ RNA drug complex spontaneously targeted cancers effectively for cancer inhibition with and without ligands. The 4WJ displayed fast renal excretion, rapid body clearance, and little organ accumulation with undetectable toxicity and immunogenicity. The safety parameters were documented by organ histology, blood biochemistry, and pathological analysis. The highly efficient cancer inhibition, undetectable drug toxicity, and favorable Chemical, Manufacturing, and Control (CMC) production of RNA nanoparticles document a candidate with high potential for translation in cancer therapy.
Assuntos
Antineoplásicos , Neoplasias Pulmonares , Nanopartículas , Humanos , RNA , Eliminação Renal , Sistemas de Liberação de Medicamentos/métodos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Nanopartículas/química , Linhagem Celular TumoralRESUMO
Betel quid (BQ) chewing is an oral habit that increases the risk of oral cancer and oral submucous fibrosis (OSF), a precancerous condition showing epithelial atrophy and tissue fibrosis. Persistent fibroblast contraction may induce the fibrotic contracture of tissue. In this study, we found that areca nut extract (ANE) (200-1200 µg/ml) stimulated buccal mucosa fibroblast (OMF)-populated collagen gel contraction. Arecoline but not arecaidine-two areca alkaloids, slightly induced the OMF contraction. Exogenous addition of carboxylesterase (2U/ml) prevented the arecoline- but not ANE-induced OMF contraction. OMF expressed inositol triphosphate (IP3) receptors. ANE-induced OMF (800 µg/ml) contraction was inhibited by U73122 [phospholipase C (PLC) inhibitor] and 2-aminoethoxydiphenyl borate (IP3 receptor antagonist), respectively. Ethylene glycol tetraacetic acid and verapamil, two calcium mobilization modulators, also suppressed the ANE-induced OMF contraction. ANE induced calcium/calmodulin kinase II and myosin light chain (MLC) phosphorylation in OMF. Moreover, W7 (a Ca(2+)/calmodulin inhibitor), HA1077 (Rho kinase inhibitor), ML-7 (MLC kinase inhibitor) and cytochalasin B (actin filament polymerization inhibitor) inhibited the ANE-induced OMF contraction. Although ANE elevated reactive oxygen species (ROS) level in OMF, catalase, superoxide dismutase and N-acetyl-L-cysteine showed no obvious effect on ANE-elicited OMF contraction. These results indicate that BQ chewing may affect the wound healing and fibrotic processes in OSF via inducing OMF contraction by ANE and areca alkaloids. AN components-induced OMF contraction was related to PLC/IP3/Ca(2+)/calmodulin and Rho signaling pathway as well as actin filament polymerization, but not solely due to ROS production.