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1.
Theranostics ; 10(2): 498-515, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31903134

RESUMO

Rationale: STING is a critical player in the innate and adaptive immune system, sensing cytosolic DNA to activate the expression of interferon genes and regulate T lymphocytes, which drives immunogenic responses to cancer cells. Tumor-associated macrophages (TAMs), abundantly present in the tumor microenvironment, play a key role in cancer development. Gastric cancer is one of the most common and leading causes in cancer-related death worldwide. However, studies on the function and regulation of STING in TAMs and their roles in gastric cancer progression are still limited. Methods: We analyzed STING and CD68 expression of 200 pairs of gastric cancer and adjacent normal tissues by immunohistochemistry to identify the prognostic values of STING, as well as the correlations between STING and CD68 in gastric cancer. The characteristics of STING-altered macrophages, as well as their effects on cancer cell apoptosis and T cell differentiation were examined by flow cytometry. Cytokines secreted by STING-altered macrophages were identified by the Human Inflammation Array3 kit. Concentrations of soluble IL24 and IFN-ß were measured by ELISA. In vivo models, including spontaneous gastric cancer in p53+/- mice and cell line-based xenografts, were established, and clinical benefits of STING-altered macrophages were examined. Results: Our study identifies STING as a prognostic factor for gastric cancer, and for the first time demonstrated that knocking-down STING and STING activation by 2'3'-c-GAMP both promote TAMs polarizing into pro-inflammatory subtype and induce apoptosis of gastric cancer cells, mechanistically through IL6R-JAK-IL24 pathway. Conclusions : This study evaluated effects of targeting STING in TAMs in anti-gastric-cancer therapies. Moreover, we unveil a novel function of STING to activate the IL6R-JAK-IL24 pathway in macrophages.

2.
Cancer Lett ; 473: 74-89, 2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-31904482

RESUMO

Gastrointestinal cancer causes countless deaths every year due to therapeutic resistance. However, whether metabolic alterations contribute to chemoresistance is not well understood. In this study, we report that fatty acid (FA) catabolism was activated in gastrointestinal cancer cells treated with oxaliplatin, which exhibited higher expression of the rate-limiting enzymes carnitine palmitoyltransferase 1B (CPT1B) and CPT2. The clinical analysis also showed that high expression of these enzymes was associated with poor oxaliplatin-based chemotherapy outcomes in patients. Furthermore, genetic or pharmacological inhibition of CPT2 with perhexiline disturbed NADPH and redox homeostasis and increased reactive oxygen species (ROS) generation and cell apoptosis in gastrointestinal cancer cells following oxaliplatin treatment. Specifically, the combination of oxaliplatin and perhexiline significantly suppressed the progression of gastrointestinal cancer in cell-based xenograft and patient-derived xenograft (PDX) models. Mechanistically, CPT2 was transcriptionally upregulated by nuclear factor of activated T cells 3 (NFATc3), which translocated to the nucleus in response to oxaliplatin treatment. In summary, our study suggests that the inhibition of CPT-mediated FA catabolism combined with conventional chemotherapy is a promising therapeutic strategy for patients with gastrointestinal cancers.

3.
Oncogene ; 39(3): 637-650, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31530934

RESUMO

Patients with stage II or III colorectal cancer (CRC) exhibit various clinical outcomes after radical treatments. The 5-year survival rate was between 50 and 87%. However, the underlying mechanisms of the variation remain unclear. Here we show that AMPKα1 is overexpressed in CRC patient specimens and the high expression is correlated with poor patient survival. We further reveal a previously unrecognized function of AMPKα1, which maintains high level of reduced glutathione to keep reduction-oxidation reaction (redox) homeostasis under stress conditions, thus promoting CRC cell survival under metabolic stress in vitro and enhancing tumorigenesis in vivo. Mechanistically, AMPKα1 regulate the glutathione reductase (GSR) phosphorylation possibly through residue Thr507 which enhances its activity. Suppression of AMPKα1 by using nano-sized polymeric vector induces a favorable therapeutic effect, especially when in combination with oxaliplatin. Our study uncovers a novel function of AMPKα1 in redox regulation and identifies a promising therapeutic strategy for treatment of CRC.

5.
Mol Cancer ; 18(1): 174, 2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31791342

RESUMO

BACKGROUND: Long noncoding RNAs (lncRNAs) play nonnegligible roles in the epigenetic regulation of cancer cells. This study aimed to identify a specific lncRNA that promotes the colorectal cancer (CRC) progression and could be a potential therapeutic target. METHODS: We screened highly expressed lncRNAs in human CRC samples compared with their matched adjacent normal tissues. The proteins that interact with LINRIS (Long Intergenic Noncoding RNA for IGF2BP2 Stability) were confirmed by RNA pull-down and RNA immunoprecipitation (RIP) assays. The proliferation and metabolic alteration of CRC cells with LINRIS inhibited were tested in vitro and in vivo. RESULTS: LINRIS was upregulated in CRC tissues from patients with poor overall survival (OS), and LINRIS inhibition led to the impaired CRC cell line growth. Moreover, knockdown of LINRIS resulted in a decreased level of insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2), a newly found N6-methyladenosine (m6A) 'reader'. LINRIS blocked K139 ubiquitination of IGF2BP2, maintaining its stability. This process prevented the degradation of IGF2BP2 through the autophagy-lysosome pathway (ALP). Therefore, knockdown of LINRIS attenuated the downstream effects of IGF2BP2, especially MYC-mediated glycolysis in CRC cells. In addition, the transcription of LINRIS could be inhibited by GATA3 in CRC cells. In vivo experiments showed that the inhibition of LINRIS suppressed the proliferation of tumors in orthotopic models and in patient-derived xenograft (PDX) models. CONCLUSION: LINRIS is an independent prognostic biomarker for CRC. The LINRIS-IGF2BP2-MYC axis promotes the progression of CRC and is a promising therapeutic target.

6.
J Vis Exp ; (149)2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31380849

RESUMO

The use of preclinical models to advance our understanding of tumor biology and investigate the efficacy of therapeutic agents is key to cancer research. Although there are many established gastric cancer cell lines and many conventional transgenic mouse models for preclinical research, the disadvantages of these in vitro and in vivo models limit their applications. Because the characteristics of these models have changed in culture, they no longer model tumor heterogeneity, and their responses have not been able to predict responses in humans. Thus, alternative models that better represent tumor heterogeneity are being developed. Patient-derived xenograft (PDX) models preserve the histologic appearance of cancer cells, retain intratumoral heterogeneity, and better reflect the relevant human components of the tumor microenvironment. However, it usually takes 4-8 months to develop a PDX model, which is longer than the expected survival of many gastric patients. For this reason, establishing primary cancer cell lines may be an effective complementary method for drug response studies. The current protocol describes methods to establish PDX models and primary cancer cell lines from surgical gastric cancer samples. These methods provide a useful tool for drug development and cancer biology research.

7.
J Cancer ; 10(10): 2299-2311, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31258733

RESUMO

Background: Lymphocytes were reported to play a significant part in host anticancer immune responses and influence tumour prognosis. Few studies have focused on the prognostic values of aspartate aminotransferase (AST) to lymphocyte ratio (ALRI), aspartate aminotransferase to platelet count ratio index (APRI) and systemic immune-inflammation index (SII) in hepatocellular carcinoma (HCC) treated with palliative treatments. Methods: Five hundred and ninety-eight HCC patients treated with palliative therapies were retrospectively analysed. We randomly assigned patients into the training cohort (429 patients) and the validation cohort I (169 patients). Receiver operating characteristic (ROC) curves were used to identify the best cut-off values for the ALRI, APRI and SII in the training cohort and the values were further validated in the validation cohort I. Correlations between ALRI and other clinicopathological factors were also analysed. A prognostic nomogram including ALRI was established. We validated the prognostic value of the ALRI, SII and APRI with two independent cohorts, the validation cohort II of 82 HCC patients treated with TACE and the validation cohort III of 150 HCC patients treated with curative resection. In the training cohort and all the validation cohorts, univariate analyses by the method of Kaplan-Meier and multivariate analysis by Cox proportional hazards regression model were carried out to identify the independent prognostic factors. Results: The threshold values of ALRI, APRI and SII were 86.3, 1.37 and 376.4 respectively identified by ROC curve analysis in the training cohort. Correlation analysis showed that ALRI>86.3 was greatly associated with higher rates of Child-Pugh B&C, portal vein tumor thrombosis (PVTT) and ascites (P < 0.05). Correspondingly, ALRI level of HCC patients with Child-Pugh B&C, PVTT and ascites was evidently higher than that of HCC patients with Child-Pugh A, without PVTT and without ascites (P < 0.001). In the training cohort and the validation cohort I, II, III, the OS of patients with ALRI >86.3 was obviously shorter than patients with ALRI ≤86.3 (P <0.001). We identified ALRI as an independent prognostic factor by univariate and multivariate analyses both in training Cohort (HR=1.481, P=0.004), validation cohort I (HR=1.511, P=0.032), validation cohort II (HR=3.166, P=0.005) and validation cohort III (HR=3.921, P=0.010). The SII was identified as an independent prognostic factor in training cohort (HR=1.356, P=0.020) and the validation cohort II (HR=2.678, P=0.002). The prognostic nomogram including ALRI was the best in predicting 3-month, 6-month, 1-year, 2-year survival And OS among TNM, ALRI, ALRI-TNM and nomogram. Conclusions: The ALRI was a novel independent prognostic index for the HCC patients treated with palliative treatments.

9.
Mol Cancer ; 18(1): 112, 2019 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-31230592

RESUMO

BACKGROUND: Colorectal carcinoma (CRC) is one of the most common malignant tumors, and its main cause of death is tumor metastasis. RNA N6-methyladenosine (m6A) is an emerging regulatory mechanism for gene expression and methyltransferase-like 3 (METTL3) participates in tumor progression in several cancer types. However, its role in CRC remains unexplored. METHODS: Western blot, quantitative real-time PCR (RT-qPCR) and immunohistochemical (IHC) were used to detect METTL3 expression in cell lines and patient tissues. Methylated RNA immunoprecipitation sequencing (MeRIP-seq) and transcriptomic RNA sequencing (RNA-seq) were used to screen the target genes of METTL3. The biological functions of METTL3 were investigated in vitro and in vivo. RNA pull-down and RNA immunoprecipitation assays were conducted to explore the specific binding of target genes. RNA stability assay was used to detect the half-lives of the downstream genes of METTL3. RESULTS: Using TCGA database, higher METTL3 expression was found in CRC metastatic tissues and was associated with a poor prognosis. MeRIP-seq revealed that SRY (sex determining region Y)-box 2 (SOX2) was the downstream gene of METTL3. METTL3 knockdown in CRC cells drastically inhibited cell self-renewal, stem cell frequency and migration in vitro and suppressed CRC tumorigenesis and metastasis in both cell-based models and PDX models. Mechanistically, methylated SOX2 transcripts, specifically the coding sequence (CDS) regions, were subsequently recognized by the specific m6A "reader", insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2), to prevent SOX2 mRNA degradation. Further, SOX2 expression positively correlated with METTL3 and IGF2BP2 in CRC tissues. The combined IHC panel, including "writer", "reader", and "target", exhibited a better prognostic value for CRC patients than any of these components individually. CONCLUSIONS: Overall, our study revealed that METTL3, acting as an oncogene, maintained SOX2 expression through an m6A-IGF2BP2-dependent mechanism in CRC cells, and indicated a potential biomarker panel for prognostic prediction in CRC.

10.
J Exp Clin Cancer Res ; 38(1): 196, 2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31088567

RESUMO

BACKGROUND: Deregulation of protein translation control is a hallmark of cancers. Eukaryotic initiation factor 4A2 (EIF4A2) is required for mRNA binding to ribosome and plays an important role in translation initiation. However, little is known about its functions in colorectal cancer (CRC). METHODS: Analysis of CRC transcriptome data from TCGA identified that EIF4A2 was associated with poor prognosis. Immunohistochemistry study of EIF4A2 was carried out in 297 paired colorectal tumor and adjacent normal tissue samples. In vitro and in vivo cell-biological assays were performed to study the biological functions of EIF4A2 on experimental metastasis and sensitivity to oxaliplatin treatment. Bioinformatic prediction, chromatin immunoprecipitation (ChIP) and dual-luciferase reporter assay were carried out to unveil the transcription factor of EIF4A2 regulation. RESULTS: EIF4A2 Expression is significantly higher in colorectal tumors. Multivariate analysis suggests EIF4A2 as an independent predictor of overall, disease-free and progression-free survival. Dysfunction of EIF4A2 by genetic knock-down or small-molecule inhibitor silvestrol dramatically inhibited CRC invasion and migration, sphere formation and enhanced sensitivity to oxaliplatin treatment in vitro and in vivo. Notably, EIF4A2 knock-down also suppressed lung metastasis in vivo. qRT-PCR and immunoblotting analyses identified c-Myc as a downstream target and effector of EIF4A2. ChIP and dual-luciferase reporter assays validated the bioinformatical prediction of ZNF143 as a specific transcription factor of EIF4A2. CONCLUSIONS: EIF4A2 promotes experimental metastasis and oxaliplatin resistance in CRC. Silvestrol inhibits tumor growth and has synergistic effects with oxaliplatin to induce apoptosis in cell-derived xenograft (CDX) and patient-derived xenograft (PDX) models.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Colorretais/metabolismo , Resistencia a Medicamentos Antineoplásicos , Fator de Iniciação 4A em Eucariotos/metabolismo , Oxaliplatina/farmacologia , Adulto , Idoso , Animais , Biomarcadores , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Feminino , Técnicas de Silenciamento de Genes , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Cell Death Dis ; 10(6): 413, 2019 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-31138787

RESUMO

Gastric cancer (GC) is one of the most common malignancies worldwide. Due to the low rate of early detection, most GC patients were diagnosed as advance stages and had poor response to chemotherapy. Some studies found that Fumarate hydratase (FH) participated in the DNA damage response and its deficiency was associated with tumorigenesis in some cancers. In this study, we investigated the relationship between FH and cisplatin (CDDP) sensitivity in GC cell lines. We found that FH was the most significant gene which induced by CDDP treatment and the suppression of FH could enhance the cytotoxicity of CDDP. Miconazole Nitrate (MN) could inhibit FH activity and enhance the effect of CDDP in vitro and in vivo. We also investigated the significance of expression of FH in GC tissues. The FH expression, which was higher in GC tissues than in noncancerous tissues, was negatively associated with the prognosis of patients. Together, these results revealed that FH is a reliable indicator for response to CDDP treatment in GC and the inhibition of FH may be a potential strategy to improve the effects of CDDP-based chemotherapy.

12.
PLoS One ; 14(5): e0217124, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31095636

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0056959.].

13.
Theranostics ; 9(4): 1115-1124, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30867819

RESUMO

Rationale: Epstein-Barr virus (EBV) is associated with multiple malignancies with expression of viral oncogenic proteins and chronic inflammation as major mechanisms contributing to tumor development. A less well-studied mechanism is the integration of EBV into the human genome possibly at sites which may disrupt gene expression or genome stability. Methods: We sequenced tumor DNA to profile the EBV sequences by hybridization-based enrichment. Bioinformatic analysis was used to detect the breakpoints of EBV integrations in the genome of cancer cells. Results: We identified 197 breakpoints in nasopharyngeal carcinomas and other EBV-associated malignancies. EBV integrations were enriched at vulnerable regions of the human genome and were close to tumor suppressor and inflammation-related genes. We found that EBV integrations into the introns could decrease the expression of the inflammation-related genes, TNFAIP3, PARK2, and CDK15, in NPC tumors. In the EBV genome, the breakpoints were frequently at oriP or terminal repeats. These breakpoints were surrounded by microhomology sequences, consistent with a mechanism for integration involving viral genome replication and microhomology-mediated recombination. Conclusion: Our finding provides insight into the potential of EBV integration as an additional mechanism mediating tumorigenesis in EBV associated malignancies.


Assuntos
DNA Viral/análise , Infecções por Vírus Epstein-Barr/complicações , Genoma Humano , Herpesvirus Humano 4/genética , Neoplasias/virologia , Integração Viral , DNA Viral/genética , Loci Gênicos , Humanos , Análise de Sequência de DNA
14.
Cancer Med ; 8(3): 1209-1217, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30729718

RESUMO

An increasing amount of evidence suggests that high-density lipoprotein cholesterol (HDL-C) is related to a positive prognosis in various cancers. However, the correlation between HDL-C and the immune signature and the prognostic role of HDL-C in stage II/III colorectal cancer (CRC) has not been previously reported. A total of 667 CRC patients were enrolled and divided into two groups based on the lower limit of normal HDL-C values (0.78 mmol/L). We used Kaplan-Meier curves and the Cox regression model to analyze the prognostic role of HDL in both disease-free survival (DFS) and overall survival (OS). Fifty-five pairs of tumor tissues were selected according to the variation in HDL-C levels (high or low) and the matched characterizes (ages, T stage, and N stage). Using immunohistochemistry, tumor tissues were stained with antibodies against CD3, CD8, CD163, iNOS, Forkhead box P3 (FOXP3), and CD33. We calculated the density of positively-stained infiltrating cells in the tumor center (TC) and invasive margin (IM). We then used Spearman rank correlation to further investigate the relationship between HDL-C levels and the immune signatures. Our results revealed that compared to patients with high HDL-C levels, patients with low HDL-C levels had poor 3-year DFS (68.9% vs 83.1%, P = 0.032) and 5-year OS rates (66.6% vs 85.3%, P = 0.002). We also identified a positive correlation between HDL-C and CD3+ , CD8+ and iNOS+ cells and a negative correlation between HDL-C and CD163+ cells in both the TC and IM. This study reveals that a low HDL-C level in stage II/III CRC patients predicts poor prognosis. The correlation between the HDL-C level and immune signature in tissue specimens suggested that HDL-C is likely to play an inhibitory role in tumor development via affecting immune responses.

15.
Gut ; 68(7): 1152-1161, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30269082

RESUMO

OBJECTIVE: To monitor trastuzumab resistance and determine the underlying mechanisms for the limited response rate and rapid emergence of resistance of HER2+ metastatic gastric cancer (mGC). DESIGN: Targeted sequencing of 416 clinically relevant genes was performed in 78 paired plasma and tissue biopsy samples to determine plasma-tissue concordance. Then, we performed longitudinal analyses of 97 serial plasma samples collected from 24 patients who were HER2+ to track the resistance during trastuzumab treatment and validated the identified candidate resistance genes. RESULTS: The results from targeted sequencing-based detection of somatic copy number alterations (SCNA) of HER2 gene were highly consistent with fluorescence in situ hybridisation data, and the detected HER2 SCNA was better than plasma carcinoembryonic antigen levels at predicting tumour shrinkage and progression. Furthermore, most patients with innate trastuzumab resistance presented high HER2 SCNA during progression compared with baseline, while HER2 SCNA decreased in patients with acquired resistance. PIK3CA mutations were significantly enriched in patients with innate resistance, and ERBB2/4 genes were the most mutated genes, accounting for trastuzumab resistance in six (35.3%) and five (29.4%) patients in baseline and progression plasma, respectively. Patients with PIK3CA/R1/C3 or ERBB2/4 mutations in the baseline plasma had significantly worse progression-free survival. Additionally, mutations in NF1 contributed to trastuzumab resistance, which was further confirmed through in vitro and in vivo studies, while combined HER2 and MEK/ERK blockade overcame trastuzumab resistance. CONCLUSION: Longitudinal circulating tumour DNA sequencing provides novel insights into gene alterations underlying trastuzumab resistance in HER2+mGC.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Genes erbB-2/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Trastuzumab/uso terapêutico , Biomarcadores Tumorais/metabolismo , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Humanos , Biópsia Líquida , Mutação , Receptor ErbB-2/metabolismo , Neoplasias Gástricas/tratamento farmacológico
16.
J Natl Cancer Inst ; 111(6): 584-596, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30534944

RESUMO

BACKGROUND: Overcoming oxidative stress is a critical step for tumor progression; however, the underlying mechanisms in colorectal cancer (CRC) remain unclear. METHODS: We investigated nicotinamide adenine dinucleotide (phosphate) (NAD(P))-dependent enzyme methylene tetrahydrofolate dehydrogenase 2 (MTHFD2) expression, clinical relevance, redox modification, and molecular mechanisms using the CRC cells and tissues (n = 462 paired samples). The antitumor effects of MTHFD2 inhibitor LY345899 on CRC tumorigenesis and metastasis were evaluated in vitro and in vivo. Data analysis used Kaplan-Meier, Pearson's correlation, and Student t test where appropriate. All statistical tests were two-sided. RESULTS: Here, we report that the patients with high expression of MTHFD2 have a shorter overall survival (HR = 1.62, 95% CI = 1.12 to 2.36, P = .01) and disease-free survival (HR = 1.55, 95% CI = 1.07 to 2.27, P = .02) than patients with low MTHFD2 expression. Suppression of MTHFD2 disturbs NADPH and redox homeostasis and accelerates cell death under oxidative stress, such as hypoxia or anchorage independence (P ≤ .01 for all). Also, genetic or pharmacological inhibition of MTHFD2 suppresses CRC cell growth and lung and peritoneal metastasis in cell-based xenografts (n = 5-8 mice per group). Importantly, LY345899 treatment statistically significantly suppresses tumor growth and decreases the tumor weight in CRC patient-derived xenograft models (n = 10 mice per group, mean [SD] tumor weight of the vehicle-treated group was 1.83 [0.19] mg vs 0.74 [0.30] mg for the LY345899-treated group, P < .001). CONCLUSIONS: Our study presents evidence that MTHFD2 confers redox homeostasis and promotes CRC cell growth and metastasis. The folate analog LY345899 as MTHFD2 inhibitor displays therapeutic activity against CRC and warrants further clinical investigation for CRC treatment.


Assuntos
Aminoidrolases/antagonistas & inibidores , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Inibidores Enzimáticos/farmacologia , Glutamatos/farmacologia , Metilenotetra-Hidrofolato Desidrogenase (NADP)/antagonistas & inibidores , Enzimas Multifuncionais/antagonistas & inibidores , Aminoidrolases/genética , Aminoidrolases/metabolismo , Animais , Anoikis/efeitos dos fármacos , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/patologia , Feminino , Humanos , Neoplasias Pulmonares/secundário , Metilenotetra-Hidrofolato Desidrogenase (NADP)/genética , Metilenotetra-Hidrofolato Desidrogenase (NADP)/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Enzimas Multifuncionais/genética , Enzimas Multifuncionais/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Distribuição Aleatória , Transdução de Sinais , Transcrição Genética , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Cell Death Discov ; 4: 116, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30588338

RESUMO

Prognostic and predictive markers are needed to predict the clinical outcomes of patients with advanced colorectal cancer (CRC) who receive standard first-line treatments. We performed a prospective cohort study in advanced CRC patients to identify a miRNA signature that could predict the benefit of receiving first-line chemotherapy for these patients. Twenty-one paired tumours and adjacent normal tissues were collected from advanced CRC patients and analysed by miRNA microarrays. Between tumour and normal tissues, 33 miRNAs were differentially expressed and was confirmed by qRT-PCR from another group of 67 patients from a prospective cohort study. A two-miRNA-based signature was obtained using the LASSO Cox regression model based on the association between the expression of each miRNA and the PFS of individual patients. Internal and external validation cohorts, including 40 and 44 patients with advanced CRC, respectively, were performed to prove the prognostic and predictive value of this signature. A signature was built based on two miRNAs, miR-125b-2-3p and miR-933. CRC patients were classified into low- and high-risk groups for disease progression based on this tool. The patients with low risk scores generally had better PFS than those with high risk scores. In the training set, the median PFS in the low- and high-risk groups were 12.00 and 7.40 months, respectively. In the internal validation set, the median PFS in the low- and high-risk groups were 9.90 and 5.10 months, respectively. In the external validation set, the median PFS in the low- and high-risk groups were 9.90 and 6.40 months, respectively. Furthermore, we detected miR-125b-2-3p associated with CRC cell sensitivity to first-line chemotherapy. Our two-miRNA-based signature was a reliable prognostic and predictive tool for tumour progression in patients with advanced CRC, and might be able to predict the benefit of receiving standard first-line chemotherapy in CRC.

18.
J Cancer ; 9(23): 4325-4333, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30519336

RESUMO

Background: Programmed death ligand 1 (PD-L1) expression has been shown to predict benefit from anti-PD-1 treatment in several cancers. However, its predictive value in colorectal cancer seems limited. This study was aimed to explore the clinical and biomarker association of programmed death ligand 1 and its spatial heterogeneous expression in colorectal cancer. Methods: Tissue microarrays of 422 primary colorectal cancers from our hospital were used for the interpretation of PD-L1 and programmed death 1 (PD-1) expression, cluster of differentiation 4 (CD4) and CD8 density and microsatellite instability (MSI) status by immunohistochemistry. To assess the spatial heterogeneity of PD-L1 expression, Tissue microarrays of 383 paired intra-primary-tumor tissues, and 105 paired lymph node metastatic tumors and 64 paired distant metastatic tumors were also used. Results: PD-L1 was positive in 188 (44.5%) primary colorectal cancers. PD-L1 expression was associated with less advanced N category (P<0.001), less advanced TNM stage (P<0.001) and less nervous invasion (P=0.04). Higher PD-L1 expression was associated with higher PD-1 expression (P<0.001), higher CD4 (P<0.001) and CD8 (P<0.001) density and DNA mismatch repair deficiency (P=0.01). PD-L1 expression was associated with better disease-free survival and overall survival, but it was only an independent prognostic factor for disease-free survival (hazard ratio and 95% confidence interval: 0.42 [0.25-0.72], P<0.001). The probability of inconsistent PD-L1 expression was respectively 17.8%, 31.4% and 39.1% within primary tumors, between primary tumors and lymph node metastatic tumors, and between primary tumors and distant metastatic tumors. All the three differences were statistically significant (P<0.001, P<0.001 and P=0.05, respectively). Conclusions: PD-L1 expression was a marker of pre-existing immune responses in colorectal cancer, however, it was heterogeneously expressed in colorectal cancer, especially between primary and metastatic tumors. This might partially explain the low-efficiency of its predictive value for benefit from anti-PD-1 treatment.

19.
Cancer Sci ; 109(11): 3575-3582, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30281875

RESUMO

The present study is the first phase II clinical trial aimed to evaluate the efficacy and safety of S-1 plus nanoparticle albumin-bound paclitaxel (Nab-PTX) as first-line chemotherapy for advanced gastric cancer (AGC). Previously untreated patients with metastatic gastric adenocarcinoma received S-1 in oral doses of 40 mg (BSA <1.25 m2 ), 50 mg (1.25 ≤ BSA < 1.50 m2 ) and 60 mg (BSA ≥1.50 m2 ) b.i.d. on days 1-14 in combination with Nab-PTX (120 mg/m2 , on days 1 and 8) for each 21-day cycle. Primary endpoint was progression-free survival (PFS), and secondary endpoints were overall response rate (ORR), overall survival (OS), disease control rate (DCR), and toxicity. A total of 73 gastric cancer patients with metastatic and measurable lesions were enrolled in the first-line setting. Median PFS and OS were 9.63 months and 14.60 months, respectively. Four (5.5%) patients had complete responses, 39 (53.4%) had partial responses (PRs), 21 (28.8%) had stable disease, four (5.5%) progressed and five (6.8%) were not evaluable. ORR and DCR were 58.9% and 87.7%, respectively. Most toxicities were mild, and no treatment-related deaths occurred. Grade 3 to 4 toxicities occurred in 22 patients (30.1%) as follows: leukopenia (13.7%), neutropenia (12.3%), anemia (5.5%), thrombocytopenia (1.4%), diarrhea (6.8%), vomiting (2.7%), stomatitis (1.4%), peripheral neuropathy (1.4%), and hand-foot syndrome (1.4%). Seven patients achieved good responses and underwent gastrectomy plus metastasectomy. Thirty (41.1%) patients had S-1 maintenance with a median of four cycles. S-1 plus Nab-PTX is an efficient and safe regimen as first-line treatment for patients with AGC.


Assuntos
Paclitaxel Ligado a Albumina/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Ácido Oxônico/administração & dosagem , Neoplasias Gástricas/tratamento farmacológico , Tegafur/administração & dosagem , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Paclitaxel Ligado a Albumina/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , China , Esquema de Medicação , Combinação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Ácido Oxônico/efeitos adversos , Análise de Sobrevida , Tegafur/efeitos adversos , Resultado do Tratamento
20.
Oncogene ; 37(46): 6025-6040, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29995871

RESUMO

Anoikis is a critical obstacle to cancer metastasis. Colorectal cancer (CRC) exhibits a high rate of metastasis, leading to death, and the mechanisms involved in anoikis resistance are still unclear. We identified that the fatty acid oxidation (FAO) pathway was activated in detached CRC cells. Multiple genes in the FAO pathway, specifically the rate-limiting enzyme CPT1A, were upregulated in CRC cells grown in suspension. Reactive oxygen species elimination mediated by CPT1A in CRC cells was vital to anoikis resistance. In vivo experiments showed that CPT1A-suppressed CRC cells colonized the lung at a much lower rate than normal CRC cells, suggesting that CPT1A-mediated FAO activation increased metastatic capacity. In clinical tissue specimens from CRC patients, elevated expression of CPT1A was observed in metastatic sites compared with primary sites. Our results demonstrate that CPT1A-mediated FAO activation induces CRC cells to resist anoikis, suggesting that CPT1A is an attractive target for treating metastatic CRC.


Assuntos
Anoikis/fisiologia , Carnitina O-Palmitoiltransferase/metabolismo , Neoplasias Colorretais/patologia , Ácidos Graxos/metabolismo , Metástase Neoplásica/patologia , Animais , Células CACO-2 , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Células HCT116 , Células HT29 , Humanos , Metabolismo dos Lipídeos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
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