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1.
Nat Commun ; 12(1): 6711, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34795238

RESUMO

Cancer stemness represents a major source of development and progression of colorectal cancer (CRC). c-Met critically contributes to CRC stemness, but how c-Met is activated in CRC remains elusive. We previously identified the lipolytic factor ABHD5 as an important tumour suppressor gene in CRC. Here, we show that loss of ABHD5 promotes c-Met activation to sustain CRC stemness in a non-canonical manner. Mechanistically, we demonstrate that ABHD5 interacts in the cytoplasm with the core subunit of the SET1A methyltransferase complex, DPY30, thereby inhibiting the nuclear translocation of DPY30 and activity of SET1A. In the absence of ABHD5, DPY30 translocates to the nucleus and supports SET1A-mediated methylation of YAP and histone H3, which sequesters YAP in the nucleus and increases chromatin accessibility to synergistically promote YAP-induced transcription of c-Met, thus promoting the stemness of CRC cells. This study reveals a novel role of ABHD5 in regulating histone/non-histone methylation and CRC stemness.

3.
Genes Dis ; 8(6): 814-826, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34522710

RESUMO

Intestinal cancers are developed from intestinal epithelial stem cells (ISCs) in intestinal crypts through a multi-step process involved in genetic mutations of oncogenes and tumor suppressor genes. ISCs play a key role in maintaining the homeostasis of gut epithelium. In 2009, Sato et al established a three-dimensional culture system, which mimicked the niche microenvironment by employing the niche factors, and successfully grew crypt ISCs into organoids or Mini-guts in vitro. Since then, the intestinal organoid technology has been used to delineate cellular signaling in ISC biology. However, the cultured organoids consist of heterogeneous cell populations, and it was technically challenging to introduce genomic changes into three-dimensional organoids. Thus, there was a technical necessity to develop a two-dimensional ISC culture system for effective genomic manipulations. In this study, we established a conditionally immortalized mouse intestinal crypt (ciMIC) cell line by using a piggyBac transposon-based SV40 T antigen expression system. We showed that the ciMICs maintained long-term proliferative activity under two-dimensional niche factor-containing culture condition, retained the biological characteristics of intestinal epithelial stem cells, and could form intestinal organoids in three-dimensional culture. While in vivo cell implantation tests indicated that the ciMICs were non-tumorigenic, the ciMICs overexpressing oncogenic ß-catenin and/or KRAS exhibited high proliferative activity and developed intestinal adenoma-like pathological features in vivo. Collectively, these findings strongly suggested that the engineered ciMICs should be used as a valuable tool cell line to dissect the genetic and/or epigenetic underpinnings of intestinal tumorigenesis.

4.
Exp Cell Res ; 395(2): 112238, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32822724

RESUMO

Human class I homeobox A13 (HOXA13) was initially identified as a transcription factor and has an important role in embryonic development and malignant transformation. However, the clinical significance and the molecular mechanisms of HOXA13 in colon cancer development and progression are still unknown. In this study, we found that HOXA13 was highly expressed in colon cancer tissues, and its expression was associated with histological grade, T stage, N stage and tumour size. In vitro studies showed that HOXA13 promoted colon cancer cell proliferation, migration and invasion. Bioinformatics analysis revealed that HOXA13 expression was positively correlated with the WNT signalling pathway. In vitro studies showed that HOXA13 promoted the malignant phenotype of colon cancer cells by facilitating the nuclear translocation of ß-Catenin. Moreover, XAV939, an inhibitor of ß-Catenin, reversed the HOXA13-mediated effects on invasion and proliferation of colon cancer cells. In vivo studies further verified that HOXA13 promoted tumour formation through the Wnt/ß-Catenin pathway. Collectively, these results suggest that HOXA13 is a potential oncogene that functions by promoting the nuclear translocation of ß-Catenin, thereby maintaining the proliferation and metastasis of colon cancer.


Assuntos
Neoplasias do Colo/metabolismo , Proteínas de Homeodomínio/metabolismo , Via de Sinalização Wnt/fisiologia , beta Catenina/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Colo/metabolismo , Neoplasias do Colo/patologia , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos
5.
Signal Transduct Target Ther ; 5(1): 35, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32296015

RESUMO

The inhibitory receptor signal regulatory protein-α (Sirpα) is a myeloid-specific immune checkpoint that engages the "don't eat me" signal CD47, which is expressed on tumor and normal tissue cells. However, the profile and regulatory mechanism of Sirpα expression in tumor-associated macrophages (TAMs) are still not clear. Here, we found that the expression of Sirpα in TAMs increased dynamically with colorectal cancer (CRC) progression. Mechanistically, CRC cell-derived lactate induced the nuclear translocation of the transcription factor Ap-2α from the cytoplasm in TAMs. Ap-2α functioned as a transcription factor for Elk-1 by binding to the conserved element GCCTGC located at -1396/-1391 in the mouse Elk-1 promoter. Subsequently, the Elk-1 protein bound to two conserved sites, CTTCCTACA (located at -229/-221) and CTTCCTCTC (located at -190/-182), in the mouse Sirpα promoter and promoted Sirpα expression in TAMs. Functionally, the macrophage-specific knockout of Ap-2α notably promoted the phagocytic activity of TAMs and suppressed CRC progression, whereas these effects were prevented by the transgenic macrophage-specific expression of Elk-1, which regulated TAM phagocytosis and CRC development in a Sirpα-dependent manner. Furthermore, we showed that Elk-1 expression was positively correlated with Sirpα expression in TAMs and was associated with poor survival in CRC patients. Taken together, our findings revealed a novel mechanism through which CRC evades innate immune surveillance and provided potential targets for macrophage-based immunotherapy for CRC patients.


Assuntos
Neoplasias Colorretais/genética , Receptores Imunológicos/genética , Fator de Transcrição AP-2/genética , Proteínas Elk-1 do Domínio ets/genética , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Xenoenxertos , Humanos , Camundongos , Camundongos Knockout , Fagocitose/genética , Fagocitose/imunologia , Células RAW 264.7 , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Macrófagos Associados a Tumor/imunologia , Macrófagos Associados a Tumor/patologia
6.
Oral Dis ; 26(2): 285-294, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31830347

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of dose-modified docetaxel plus cisplatin and 5-fluorouracil (TPF) in Chinese patients with squamous cell carcinoma of the head and neck (SCCHN). MATERIALS AND METHODS: This Phase III, open-label, multi-center study included Chinese adults with previously untreated TNM Stage III or IV SCCHN (NCT00995293). Patients were randomized (1:1) to induction chemotherapy with TPF (docetaxel 60 mg/m2 and cisplatin 60 mg/m2 on day 1 and 5-FU 750 mg/m2  per day continuous IV infusion on days 1-5) or PF (cisplatin 75 mg/m2 on day 1 and 5-FU 750 mg/m2  per day on days 1-5) every 3 weeks for 3-4 cycles. The primary endpoint was progression-free survival (PFS). RESULTS: Median PFS in the TPF (n = 108) and PF (n = 111) groups was 400 days and 342 days (HR = 0.75; 95% CI, 0.53─1.06; p = .227), respectively. Overall response rate was higher for TPF versus PF (76.3% vs. 52.9%; p = .001), although this equalized following radiotherapy (75.0% vs. 73.9%). In the TPF and PF groups, ≥1 treatment-emergent adverse event was experienced by 104 (94.5%) and 110 (93.2%) patients, respectively. CONCLUSION: Adding dose-modified docetaxel to PF did not significantly improve PFS but may increase anti-tumor activity in Chinese patients with locally advanced SCCHN.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Docetaxel/administração & dosagem , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Terapia Neoadjuvante , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Adolescente , Adulto , Idoso , Cisplatino/administração & dosagem , Intervalo Livre de Doença , Fluoruracila/administração & dosagem , Humanos , Pessoa de Meia-Idade , Taxoides/administração & dosagem , Adulto Jovem
7.
Adv Ther ; 36(8): 1986-1998, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31209700

RESUMO

INTRODUCTION: To assess the risk factors associated with regorafenib-related adverse events (AEs) in metastatic colorectal cancer (mCRC) and gastrointestinal stromal tumors (GIST). We also evaluated different measures of combatting AEs and their success rate to aid physicians in early identification and management of reported AEs. METHODS: A literature search was conducted through the electronic databases PubMed, Embase, and Cochrane Central Register of Controlled Trials up to May 2018 according to the pre-specified inclusion and exclusion criteria. Pooled estimates with Pearson correlation were obtained with fixed or random-effects models. RESULTS: From our analysis, it was evident that AEs were more common in patients aged less than 65 years compared to those aged at least 65 years (71.3% vs. 27.6%, p = 0.001). A statistically significant correlation was observed between the occurrence of AEs and a dose of 160 mg (r = 0.967; p = 0.001) while no significant correlation was found at 120 mg and 80 mg. The common measures used to manage AEs included lowering the regorafenib dose (41%), intermittent drug withdrawal (66.7%), and complete drug withdrawal (19%). About 57% of patients recovered from AE after their initiating dose was lowered. CONCLUSION: Regorafenib-associated AEs are more common at an initiating dose of 160 mg. Considering that the efficacy depends on the dosage, 120 mg might be a better choice for mCRC and GIST patients; further studies are needed to validate the results of our analysis. Further prompt identification and management of AEs are required to help the patients continue with drug therapy.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/terapia , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Compostos de Fenilureia/efeitos adversos , Compostos de Fenilureia/uso terapêutico , Piridinas/efeitos adversos , Piridinas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
8.
Nat Commun ; 10(1): 1078, 2019 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-30842415

RESUMO

The efficacy of Fluorouracil (FU) in the treatment of colorectal cancer (CRC) is greatly limited by drug resistance. Autophagy has been implicated in chemoresistance, but the role of selective autophagic degradation in regulating chemoresistance remains unknown. In this study, we revealed a critical role of ABHD5 in charging CRC sensitivity to FU via regulating autophagic uracil yield. We demonstrated that ABHD5 localizes to lysosome and interacts with PDIA5 to prevent PDIA5 from interacting with RNASET2 and inactivating RNASET2. ABHD5 deficiency releases PDIA5 to directly interact with RNASET2 and leave RNASET2 in an inactivate state, which impairs RNASET2-mediated autophagic uracil yield and promotes CRC cells to uptake FU as an exogenous uracil, thus increasing their sensitivity to FU. Our findings for the first time reveal a novel role of ABHD5 in regulating lysosome function, highlighting the significance of ABHD5 as a compelling biomarker predicting the sensitivity of CRCs to FU-based chemotherapy.


Assuntos
1-Acilglicerol-3-Fosfato O-Aciltransferase/metabolismo , Antimetabólitos Antineoplásicos/farmacologia , Autofagia , Neoplasias Colorretais/terapia , Fluoruracila/farmacologia , 1-Acilglicerol-3-Fosfato O-Aciltransferase/genética , Animais , Antimetabólitos Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/metabolismo , Carcinogênese/patologia , Quimioterapia Adjuvante/métodos , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Conjuntos de Dados como Assunto , Progressão da Doença , Intervalo Livre de Doença , Resistencia a Medicamentos Antineoplásicos , Fluoruracila/uso terapêutico , Técnicas de Silenciamento de Genes , Células HCT116 , Humanos , Estimativa de Kaplan-Meier , Lisossomos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos SCID , Ribonucleases/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Uracila/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Lung Cancer ; 130: 18-24, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30885342

RESUMO

OBJECTIVES: Sequential combination of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) and chemotherapy has shown greater benefits than either treatment alone in non-small-cell lung cancer (NSCLC). In this follow-up of the ENSURE study, we evaluated progression-free survival (PFS) with first-line erlotinib followed by chemotherapy at progression versus the inverse treatment sequence in 175 Chinese patients with EGFR mutation-positive NSCLC. MATERIALS AND METHODS: Forty-five of the 175 patients included in the follow-up analysis experienced progressive disease (PD). Those with PD on first-line erlotinib (n = 24) received gemcitabine/cisplatin while those who failed first-line chemotherapy (n = 21) received erlotinib until second-line PD. The primary endpoint was PFS in the crossover subpopulation. Post-hoc analysis of survival outcomes was also measured for the overall population of 175 Chinese patients. RESULTS: Among patients who crossed over at progression, PFS was comparable between those who received second-line erlotinib and those who received second-line chemotherapy (median, 26.3 months and 23.4 months, respectively; P = 0.529). Regardless of the sequence in which the therapies were administered, patients in the crossover treatment subgroup benefited from either second-line therapy after progression with a median overall survival of 51.6 months versus 23.0 months achieved among patients in the non-crossover treatment subgroup. Post-hoc biomarker analyses of Kaplan-Meier survival curves and Cox regression showed that survival benefits with either treatment sequence were similar between patients with circulating free DNA EGFR mutations in exons 19 and 21; however, those with undetectable mutations achieved significantly greater survival benefits. CONCLUSION: In advanced EGFR mutation-positive NSCLC, first-line erlotinib followed by chemotherapy at progression demonstrated comparable PFS benefit with the inverse treatment sequence, irrespective of mutation subtype. Utilizing both EGFR-TKIs and chemotherapy, irrespective of the sequence, maximizes survival benefits for patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Cisplatino/uso terapêutico , Desoxicitidina/análogos & derivados , Cloridrato de Erlotinib/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Adulto , Idoso , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , China , Estudos Cross-Over , Desoxicitidina/uso terapêutico , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Mutação/genética , Estadiamento de Neoplasias , Análise de Sobrevida , Resultado do Tratamento
10.
Cell Death Dis ; 10(2): 40, 2019 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-30674873

RESUMO

Cancer cells re-program their metabolic machinery to meet the requirements of malignant transformation and progression. Glutaminase 1 (GLS1) was traditionally known as a mitochondrial enzyme that hydrolyzes glutamine into glutamate and fuels rapid proliferation of cancer cells. However, emerging evidence has now revealed that GLS1 might be a novel oncogene involved in tumorigenesis and progression of human cancers. In this study, we sought to determine whether GLS1 implicated in invasion and metastasis of colorectal carcinoma, and its underlying molecular mechanism. By analyzing a large set of clinical data from online datasets, we found that GLS1 is overexpressed in cancers compared with adjacent normal tissues, and associated with increased patient mortality. Immunohistochemical analysis of GLS1 staining showed that high GLS1 expression is significantly correlated with lymph node metastasis and advanced clinical stage in colorectal cancer patients. To investigate the underlying mechanism, we analyzed the Cancer Genome Atlas database and found that GLS1 mRNA expression is associated with a hypoxia signature, which is correlated with an increased risk of metastasis and mortality. Furthermore, reduced oxygen availability increases GLS1 mRNA and protein expression, due to transcriptional activation by hypoxia-inducible factor 1. GLS1 expression in colorectal cancer cells is required for hypoxia-induced migration and invasion in vitro and for tumor growth and metastatic colonization in vivo.


Assuntos
Neoplasias Colorretais/metabolismo , Glutaminase/metabolismo , Animais , Carcinogênese , Hipóxia Celular/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Progressão da Doença , Glutaminase/genética , Células HT29 , Xenoenxertos , Humanos , Masculino , Camundongos , Camundongos SCID , Metástase Neoplásica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sobrevida
12.
J Clin Oncol ; 36(30): 3031-3039, 2018 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-30199311

RESUMO

PURPOSE: Cetuximab in combination with chemotherapy is a standard-of-care first-line treatment regimen for patients with RAS wild-type (wt) metastatic colorectal cancer (mCRC); however, the efficacy of cetuximab plus leucovorin, fluorouracil, and oxaliplatin (FOLFOX) has never before been proven in a controlled and randomized phase III trial. To our knowledge, the TAILOR trial ( ClinicalTrials.gov identifier: NCT01228734) is the first randomized, multicenter, phase III study of the addition of cetuximab to first-line FOLFOX prospectively choosing a RAS wt population and thus providing confirmative data for the efficacy and safety of cetuximab plus FOLFOX versus FOLFOX alone. PATIENTS AND METHODS: TAILOR is an open-label, randomized (1:1), multicenter, phase III trial in patients from China comparing FOLFOX-4 with or without cetuximab in RAS wt (KRAS/NRAS, exons 2 to 4) mCRC. The primary end point of TAILOR was progression-free survival time; secondary end points included overall survival time, overall response rate, and safety and tolerability. RESULTS: In the modified intent-to-treat population of 393 patients with RAS wt mCRC, adding cetuximab to FOLFOX-4 significantly improved the primary end point of progression-free survival time compared with FOLFOX-4 alone (hazard ratio, 0.69; 95% CI, 0.54 to 0.89; P = .004; median, 9.2 v 7.4 months, respectively), as well as the secondary end points of overall survival time (current assessment after 300 events: hazard ratio, 0.76; 95% CI, 0.61 to 0.96; P = .02; median, 20.7 v 17.8 months, respectively) and overall response rate (odds ratio, 2.41; 95% CI, 1.61 to 3.61; P < .001; 61.1% v 39.5%, respectively). Treatment was well tolerated, and there were no new or unexpected safety findings. CONCLUSION: The TAILOR study met all of its objectives and relevant clinical end points, confirming cetuximab in combination with FOLFOX as an effective standard-of-care first-line treatment regimen for patients with RAS wt mCRC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cetuximab/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Adulto , Idoso , Cetuximab/efeitos adversos , China , Neoplasias Colorretais/mortalidade , Feminino , Fluoruracila/uso terapêutico , Humanos , Leucovorina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/uso terapêutico , Intervalo Livre de Progressão , Adulto Jovem
13.
Nat Commun ; 9(1): 2574, 2018 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-29968710

RESUMO

Metabolic reprogramming greatly contributes to the regulation of macrophage activation. However, the mechanism of lipid accumulation and the corresponding function in tumor-associated macrophages (TAMs) remain unclear. With primary investigation in colon cancer and confirmation in other cancer models, here we determine that deficiency of monoacylglycerol lipase (MGLL) results in lipid overload in TAMs. Functionally, macrophage MGLL inhibits CB2 cannabinoid receptor-dependent tumor progression in inoculated and genetic cancer models. Mechanistically, MGLL deficiency promotes CB2/TLR4-dependent macrophage activation, which further suppresses the function of tumor-associated CD8+ T cells. Treatment with CB2 antagonists delays tumor progression in inoculated and genetic cancer models. Finally, we verify that expression of macrophage MGLL is decreased in cancer tissues and positively correlated with the survival of cancer patients. Taken together, our findings identify MGLL as a switch for CB2/TLR4-dependent macrophage activation and provide potential targets for cancer therapy.


Assuntos
Macrófagos/imunologia , Monoacilglicerol Lipases/metabolismo , Neoplasias/patologia , Receptor CB2 de Canabinoide/metabolismo , Idoso , Animais , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Humanos , Metabolismo dos Lipídeos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Monoacilglicerol Lipases/genética , Neoplasias/imunologia , Cultura Primária de Células , Células RAW 264.7 , Receptor CB2 de Canabinoide/antagonistas & inibidores , Receptor CB2 de Canabinoide/genética , Receptor CB2 de Canabinoide/imunologia , Receptor 4 Toll-Like/metabolismo
14.
ACS Appl Mater Interfaces ; 10(25): 21137-21148, 2018 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-29882656

RESUMO

Human telomerase reverse transcriptase (hTERT) has been found to be closely related to tumor transformation, growth, and metastasis. Thus, the delivery of hTERT small interfering RNA (siRNA) is an important approach for cancer gene therapy. However, the single anticancer effect of gene silencing is often limited by poor specificity or low efficiency in siRNA delivery and release. In this work, we present small and thin black phosphorus (BP) nanosheets as a biodegradable delivery system for hTERT siRNA. The BP nanosheets prepared with poly(ethylene glycol) (PEG) and polyethylenimine (PEI) modification (PPBP), exhibited high siRNA loading capacity and robust cell uptake. The PPBP nanosheets also exhibited potent photodynamic therapy/photothermal therapy (PDT/PTT) activities when exposed to different wavelengths of laser irradiation. More importantly, PPBP nanosheets underwent a gradual degradation when presented in a mixture of low pH and reactive oxygen species (ROS)-rich environment. The degradation of PPBP was strengthened especially after local and minimal invasive PDT treatment, because of excessive ROS production. Further delivery and release of siRNA to the cytoplasm for gene silencing was achieved by PEI-aided escape from the acidic lysosome. Thus, PPBP-siRNA efficiently inhibited tumor growth and metastasis by specific delivery of hTERT siRNA and a synergistic combination of targeted gene therapy, PTT and PDT.


Assuntos
Fósforo/química , Linhagem Celular Tumoral , Terapia Genética , Humanos , Neoplasias , Polietilenoimina , RNA Interferente Pequeno
15.
Gut ; 67(2): 307-319, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-27849558

RESUMO

OBJECTIVE: As the modulation of autophagic processes can be therapeutically beneficial to cancer treatment, the identification of novel autophagic enhancers is highly anticipated. However, current autophagy-inducing anticancer agents exert undesired side effects owing to their non-specific biodistribution in off-target tissues. This study aims to develop a multifunctional agent to integrate cancer targeting, imaging and therapy and to investigate its mechanism. DESIGN: A series of mitochondria-targeting near-infrared (NIR) fluorophores were synthesised, screened and identified for their autophagy-enhancing activity. The optical properties and biological effects were tested both in vitro and in vivo. The underlying mechanism was investigated using inhibitors, small interfering RNA (siRNA), RNA sequencing, mass spectrometry and human samples. RESULTS: We have screened and identified a new NIR autophagy-enhancer, IR-58, which exhibits significant tumour-selective killing effects. IR-58 preferentially accumulates in the mitochondria of colorectal cancer (CRC) cells and xenografts, a process that is glycolysis-dependent and organic anion transporter polypeptide-dependent. IR-58 kills tumour cells and induces apoptosis via inducing excessive autophagy, which is mediated through the reactive oxygen species (ROS)-Akt-mammalian target of rapamycin (mTOR) pathway. RNA sequencing, mass spectrometry and siRNA interference studies demonstrate that translocase of inner mitochondrial membrane 44 (TIM44)-superoxide dismutase 2 (SOD2) pathway inhibition is responsible for the excessive ROS, autophagy and apoptosis induced by IR-58. TIM44 expression correlates positively with CRC development and poor prognosis in patients. CONCLUSIONS: A novel NIR small-molecule autophagy-enhancer, IR-58, with mitochondria-targeted imaging and therapy capabilities was developed for CRC treatment. Additionally, TIM44 was identified for the first time as a potential oncogene, which plays an important role in autophagy through the TIM44-SOD2-ROS-mTOR pathway.


Assuntos
Autofagia/efeitos dos fármacos , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Corantes Fluorescentes/farmacologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mitocôndrias/enzimologia , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Feminino , Fluorescência , Corantes Fluorescentes/uso terapêutico , Células HCT116 , Células HT29 , Células Hep G2 , Humanos , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Proteínas de Transporte da Membrana Mitocondrial , Fenômenos Ópticos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/genética , Superóxido Dismutase/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Oncotarget ; 8(40): 67670-67683, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28978062

RESUMO

Glucocorticoids are effective to treat lymphoma and leukemia. Their effect in colon cancer remains far from clear. Here, we found that glucocorticoid receptor (GR) α protein level was dramatically lower in colon cancer than in lymphoma. Colon cell lines LoVo and HCT116 were GRα-rich and GRα was not detectable in HT29 or SW480. Dexamethasone significantly inhibited cell growth of GRα-rich cell lines and did not significantly affect GRα-negative cell lines. Dexamethasone induced apoptosis and increased chemosensitivity of GRα-rich cell lines. Knockdown of GRα significantly attenuated dexamethasone effects on cell growth, apoptosis and chemosensitivity. NF-κB p65 significantly correlated with GRα in colon cancer samples. Dexamethasone decreased NF-κB p65 activity. Knockdown of NF-κB p65 increased apoptosis. Our data demonstrate GRα protein level is dramatically lower in colon cancer than in lymphoma. Dexamethasone inhibits cell growth, induces apoptosis and enhances chemosensitivity in colon cancer, at least partly, via GRα and NF-κB.

17.
PLoS One ; 12(10): e0184501, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29065135

RESUMO

TW-37 is a novel, potent and non-peptide Bcl-2 small-molecule inhibitor. Its activity in colorectal cancer (CRC) cells is studied. In both HCT-116 cells and primary human colon cancer cells, treatment with TW-37 at only nM concentration efficiently inhibited cell survival and proliferation. TW-37 also induced caspase-3/9 and apoptosis activation in CRC cells. Feedback autophagy activation was observed in TW-37-treated CRC cells. Reversely pharmacological autophagy inhibition or Beclin-1 knockdown by targeted-shRNA potentiated TW-37-induced apoptosis and killing of CRC cells. In vivo, intravenous injection of TW-37 inhibited HCT-116 tumor growth in mice. TW-37's anti-tumor activity was further potentiated against Beclin-1-silenced HCT-116 tumors. Together, targeting Bcl-2 family protein by TW-37 efficiently inhibits CRC cell growth in vitro and in vivo. Inhibition of feedback autophagy activation could further sensitize TW-37.


Assuntos
Benzamidas/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Sulfonas/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Benzamidas/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/patologia , Células HCT116 , Humanos , Camundongos , Camundongos SCID , Sulfonas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Immunity ; 47(3): 538-551.e5, 2017 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-28930662

RESUMO

Follicular regulatory T (Tfr) cells differentiate from conventional regulatory T (Treg) cells and suppress excessive germinal center (GC) responses by acting on both GC B cells and T follicular helper (Tfh) cells. Here, we examined the impact of mTOR, a serine/threonine protein kinase that senses and integrates diverse environmental cues, on the differentiation and functional competency of Tfr cells in response to protein immunization or viral infection. By genetically deleting Rptor or Rictor, essential components for mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2), respectively, we found that mTORC1 but not mTORC2 is essential for Tfr differentiation. Mechanistically, mTORC1-mediated phosphorylation of the transcription factor STAT3 induced the expression of the transcription factor TCF-1 by promoting STAT3 binding to the Tcf7 5'-regulatory region. Subsequently, TCF-1 bound to the Bcl6 promoter to induce Bcl6 expression, which launched the Tfr cell differentiation program. Thus, mTORC1 initiates Tfr cell differentiation by activating the TCF-1-Bcl-6 axis during immunization or infection.


Assuntos
Imunomodulação , Complexos Multiproteicos/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Biomarcadores , Diferenciação Celular/imunologia , Análise por Conglomerados , Perfilação da Expressão Gênica , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Imunização , Imunofenotipagem , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Transgênicos , Complexos Multiproteicos/genética , Proteínas Proto-Oncogênicas c-bcl-6/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Linfócitos T Reguladores/citologia , Serina-Treonina Quinases TOR/genética
19.
J Cancer ; 8(7): 1187-1196, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28607593

RESUMO

Purpose To investigate the correlation between chemoresistance of colorectal cancer to 5-fluorouracil and BNIP3 and the underlying mechanism. Methods BNIP3 protein in specimens was evaluated using immunohistochemistry. Semi-quantitative reverse transcription PCR and Western blot was employed to assay gene expression. The promoter methylation status of BNIP3 was examined by methylation-specific PCR. Drug sensitivity was assayed using MTT assay. Results Specimens from 81 patients with colorectal cancer receiving 5-fluorouracil-based chemotherapy were analyzed. BNIP3 expression was negative in 42 cancer samples. The mean score of BNIP3 in cancer was 1.8±0.2 and it was 3.7±0.5 in adjacent colorectum (p<0.05). The response rate of the BNIP3 positive group was 63.6% and that of the negative group was 36.4% (p=0.021). The median PFS of the BNIP3 positive group was 9.25 months and that of the BNIP3 negative group was 6.5 months (p=0.011). BNIP3 mRNA was not detectable in 4 of 8 colorectal cell lines and all these 4 cell lines displayed BNIP3 methylated allele only. Other 4 cell lines what expressed detectable BNIP3 displayed BNIP3 unmethylated allele only or both unmethylated and methylated alleles. 5-Aza dramatically increased BNIP3 expression. Knockdown of DNMT1 increased BNIP3. Knockdown of DNMT3B alone did not detectably change BNIP3 expression while knockdown of both DNMT1 and DNMT3B increased BNIP3 expression more than knockdown of DNMT1 alone. Knockdown of BNIP3 decreased chemosensitivity to 5-fluorouracil and increasing BNIP3 through demethylation increased chemosensitivity. Conclusion Chemoresistance of colorectal cancer to 5-fluorouracil is associated with silencing of the BNIP3 gene through aberrant methylation via DNMT1/DNMT3B.

20.
Mol Ther ; 25(5): 1248-1258, 2017 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-28366766

RESUMO

Chimeric antigen receptor T (CAR-T) cells have shown promising efficacy in treatment of hematological malignancies, but its applications in solid tumors need further exploration. In this study, we investigated CAR-T therapy targeting carcino-embryonic antigen (CEA)-positive colorectal cancer (CRC) patients with metastases to evaluate its safety and efficacy. Five escalating dose levels (DLs) (1 × 105 to 1 × 108/CAR+/kg cells) of CAR-T were applied in 10 CRC patients. Our data showed that severe adverse events related to CAR-T therapy were not observed. Of the 10 patients, 7 patients who experienced progressive disease (PD) in previous treatments had stable disease after CAR-T therapy. Two patients remained with stable disease for more than 30 weeks, and two patients showed tumor shrinkage by positron emission tomography (PET)/computed tomography (CT) and MRI analysis, respectively. Decline of serum CEA level was apparent in most patients even in long-term observation. Furthermore, we observed persistence of CAR-T cells in peripheral blood of patients receiving high doses of CAR-T therapy. Importantly, we observed CAR-T cell proliferation especially in patients after a second CAR-T therapy. Taken together, we demonstrated that CEA CAR-T cell therapy was well tolerated in CEA+ CRC patients even in high doses, and some efficacy was observed in most of the treated patients.


Assuntos
Adenocarcinoma/terapia , Antígeno Carcinoembrionário/genética , Neoplasias Colorretais/terapia , Neoplasias Hepáticas/terapia , Recidiva Local de Neoplasia/terapia , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T/imunologia , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/imunologia , Adenocarcinoma/secundário , Idoso , Antígeno Carcinoembrionário/imunologia , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Citotoxicidade Imunológica , Relação Dose-Resposta Imunológica , Feminino , Expressão Gênica , Humanos , Imunoterapia Adotiva , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/secundário , Ativação Linfocitária , Depleção Linfocítica , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Proteínas Mutantes Quiméricas/genética , Proteínas Mutantes Quiméricas/imunologia , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/imunologia , Recidiva Local de Neoplasia/patologia , Engenharia de Proteínas , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/citologia , Linfócitos T/transplante
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