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1.
BMC Cancer ; 19(1): 1061, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31703584

RESUMO

BACKGROUND: To reveal roles of reactive oxygen species (ROS) status in chemotherapy resistance and to develop a ROS scoring system for prognosis prediction in ovarian cancer. METHODS: We tested the sensitizing effects of ROS elevating drugs to cisplatin (cDDP) in ovarian cancer both in vitro and in vivo. A ROS scoring system was developed using The Cancer Genome Atlas (TCGA) database of ovarian cancer. The associations between ROS scores and overall survival (OS) were analyzed in TCGA, Tothill dataset, and our in-house dataset (TJ dataset). RESULTS: ROS-inducing drugs increased cisplatin-induced ovarian cancer cell injury in vitro and in vivo. ROS scoring system was established using 25 ROS-related genes. Patients were divided into low (scores 0-12) and high (scores 13-25) score groups. Improved patient survival was associated with higher scores (TCGA dataset hazard ratio (HR) = 0.43, P < 0.001; Tothill dataset HR = 0.65, P = 0.022; TJ dataset HR = 0.40, P = 0.003). The score was also significantly associated with OS in multiple datasets (TCGA dataset r2 = 0.574, P = 0.032; Thothill dataset r2 = 0.266, P = 0.049; TJ dataset r2 = 0.632, P = 0.001) and with cisplatin sensitivity in ovarian cancer cell lines (r2 = 0.799, P = 0.016) when used as a continuous variable. The scoring system showed better prognostic performance than other clinical factors by receiver operating characteristic (ROC) curves (TCGA dataset area under the curve (AUC) = 0.71 v.s. 0.65, Tothill dataset AUC = 0.73 v.s. 0.67, TJ dataset AUC = 0.74 v.s. 0.66). CONCLUSIONS: ROS status is associated with chemotherapy resistance. ROS score system might be a prognostic biomarker in predicting the survival benefit from ovarian cancer patients.

2.
Oncogene ; 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31705064

RESUMO

Ovarian cancer selective metastasizes to the omentum contributing to the poor prognosis associated with ovarian cancer. However, the mechanism underlining this propensity and therapeutic approaches to counter this process has not been fully elucidated. Here, we show that MCP-1 produced by omental adipocytes binding to its cognate receptor CCR-2 on ovarian cancer cells facilitates migration and omental metastasis by activating the PI3K/AKT/mTOR pathway and its downstream effectors HIF-1α and VEGF-A in cell lines, xenografts, and transgenic murine models. MCP-1 antibody significantly decreased tumor burden and increased survival of mice in vivo. Interestingly, metformin decreased omental metastasis at least partially by inhibiting MCP-1 secretion from adipocytes independent of direct effects on cancer cells. Together this suggests a novel target of MCP-1/CCR-2 axis that could benefit ovarian cancer patients.

3.
Theranostics ; 9(24): 7325-7344, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695771

RESUMO

Metastasis is one of the most threatening aspects of cervical cancer. We developed a method to intraoperatively map the primary tumor, metastasis and metastatic sentinel lymph nodes (SLNs), providing real-time intraoperative guidance in cervical cancer. Methods: TMTP1, a tumor metastasis targeting peptide, was employed to modify the indocyanine green (ICG)-loaded poly (ethylene glycol)- poly (lactic-co-glycolic acid) (PEG-PLGA) micelles. The cervical cancer subcutaneous tumor model and lung metastasis model were established to determine the active targeting of ICG-loaded TMTP1-PEG-PLGA micelles (ITM) for the primary tumor and occult metastasis of cervical cancer. Human cervical cancer HeLa cells engineered by firefly luciferase were injected into the right hocks of BALB/c nude mice to develop the SLN metastasis model. The ITM and control ICG-loaded PEG-PLGA micelles (IM) were injected into the right hind footpads in the SLN metastasis model, and the migration and retention of micelles were recorded under near-infrared fluorescence. K14-HPV16 transgenic mice were also used to detect the image capability of ITM to target cancerous lesions. Results: ITM could actively target imaging of the primary tumor and cervical cancer metastasis. ITM quickly diffused from the injection site to SLNs along lymphatic capillaries and remained in the SLNs for 12 h. Moreover, ITM specifically accumulated in the tumor metastatic SLNs (T-SLNs), which could be successfully distinguished from normal SLNs (N-SLNs). Conclusion: ITM could achieve active targeting of the primary tumor, metastasis and T-SLNs, providing precise and real-time intraoperative guidance for cervical cancer.

5.
Gynecol Oncol ; 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31604662

RESUMO

OBJECTIVE: Human papillomavirus (HPV) 16/18 genotyping is an effective method for triage of high-risk (hr) HPV-positive women in primary hrHPV screening for cervical cancer. The present study aimed to evaluate whether co-infected with other hrHPV types will affect the risk of cervical carcinogenesis in HPV16/18 positive women. METHODS: A total of 313,704 women aged ≥30 years were screened in China. Among them, 4,933 HPV16/18-positive participants underwent colposcopy-directed biopsy. The HPV genotypes were identified using the Cobas HPV genotyping system. Multinomial logistic regression was used to model different HPV16/18 infection patterns. RESULTS: The overall prevalence rates of hrHPV and HPV16/18 were 7.85% (24,456/311,382) and 1.95% (6,086/311,382) respectively. Among HPV16/18 positive individuals, 33.24% (2,023/6,086) were co-infection with multiple types. Of the 4933 women who underwent colposcopy, their HPV16/18 infection patterns were as follows: 52.38% (2,584/4,933) HVP16 only, 23.54% (1,161/4,933) HPV16 + other hrHPVs, 14.98% (739/4,933) HPV18 only, 6.83% (337/4,933) HPV18 + other hrHPVs, 1.13% (56/4,933) HPV16 + 18, 1.13% (56/4,933) HPV16 + 18+other hrHPVs. After adjusting for cofactors, compared with single HPV16 infection, the risk of developing cervical intraepithelial neoplasia (CIN) grade 3 or greater (CIN3+) was significantly lower in HPV16 + other hrHPVs group (odds ratio [OR] = 0.637, 95% confidence interval [CI] = 0.493-0.822). CONCLUSION: HPV16/18 co-infection with other hrHPVs is a common phenomenon. Different HPV16/18 infection patterns may influence the risk of cervical carcinogenesis. HPV16 co-infected with other hrHPVs appears to have a lower associated risk of CIN3+ in ≥30 years old women.

6.
J Exp Clin Cancer Res ; 38(1): 415, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31615580

RESUMO

In the original publication of this manuscript [1], Fig. 5E lower panel was incorrect due to an error in the preparation of these figures for publication. It was noticed that in the lower panel of Fig. 5E, one mouse image of ApoE-/- + PBS group (upper) was a photograph coming from ApoE-/- + BAPN pre-treatment group (lower). The corrected figure appears below. We apologize for any confusion this may have caused.

7.
EBioMedicine ; 2019 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-31636012

RESUMO

BACKGROUND: Understanding how cells respond to mitotic poisons is of great biomedical and clinical significance. However, it remains unknown how cell-death or survival is determined during exposure to anti-mitotic drugs. METHODS: The biological effects of SLC39A6 (LIV-1) and GrpE-like 1 (GRPEL1) on mitotic exit and apoptosis were evaluated both in vitro and in vivo using flow cytometry, western blotting, xenografts and time-lapse imaging. The interactions between proteins and the ubiquitination of GRPEL1 were assessed by GST pull down, immunoprecipitation and mass spectrometry analysis. The expression of LIV-1 in cancers was assessed by immunohistochemistry. FINDINGS: Overexpression of LIV-1 led to direct apoptosis. Depleted for LIV-1 evade anti-mitotic agent-induced killing through a rapid exit from arrested mitosis. LIV-1 interacts with GRPEL1 and Stabilizes GRPEL1 Protein by Preventing Ubiquitylation of GRPEL1. LIV-1-GRPEL1 axis depletion works to reduce the mitotic arrest by inducing PP2A-B55α phosphates activity, while inhibit apoptosis by banding AIF and preventing the latter's release into the nucleus. Loss of function in this axis was frequent in multiple types of human epithelial cancer. INTERPRETATION: These data demonstrate that LIV-1-GRPEL1 axis dually regulates mitotic exit as well as apoptosis by interacting with PP2A B55α and AIF. Its discovery constitutes a conceptual advance for the decisive mechanism of cell fate during damaged mitosis. FUND: National Clinical Research Center for Obstetric and Gynecologic Diseases, the National Natural Science Foundation of China.

9.
Exp Cell Res ; 383(1): 111495, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31301290

RESUMO

Angiogenesis plays important roles in solid tumors progression. Growth factors such as vascular endothelial growth factors (VEGFs) can induce angiogenesis and hypoxia promotes the expression of VEGFs through activating hypoxia-inducible factor 1 (HIF-1α). However, the regulation of HIF-1α still not been fully understood. Here, we demonstrate that the Sine Oculis Homeobox Homolog 4 (SIX4) is up-regulated in colorectal cancer (CRC) and high expression of SIX4 predicts a poor prognosis. Overexpression of SIX4 enhances tumor growth and angiogenesis in vitro and in vivo, while knockdown of SIX4 inhibits tumor growth and angiogenesis. Furthermore, we show that SIX4 increases the expression of VEGF-A by coordinating with the HIF-1α. Mechanically, we explore that SIX4 up-regulates the expression of HIF-1α depending on Akt activation. Collectively, we demonstrate that SIX4 is functional in regulating tumor angiogenesis and SIX4 might be used as anti-angiogenic therapy in CRC.

10.
Anal Chim Acta ; 1075: 137-143, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31196419

RESUMO

Nucleic acid probes are very useful tools in biological and medical science. However, the essential sensing mechanism of nucleic acid probes was prone to the interference of surrounding sequences. Especially when the target sequences formed secondary structures such as hairpin or quadruplex, the nucleic acid probes were hindered from hybridizing with target strands, greatly disabled the function of probes. Herein, we have established an Open strand based strategy for eliminating the influence of secondary structures on the performance of nucleic acid probes. The strategy was general toward different lengths, secondary structures and sequences of the targeting strand, and we found that the improvement was higher when the secondary structure of the targeting strand was more complicated. Experiments on synthetic single stranded DNA and real clinical genomic DNA samples were conducted for low abundance mutation detection, and the limit of detection for TERT-C228T and BRCA2 rs80359065 mutations could be 0.02% and 0.05% respectively, demonstrating the clinical practicability of our proposed strategy in low abundance mutation detection.


Assuntos
Sondas de DNA/química , DNA de Cadeia Simples/análise , Proteína BRCA2/genética , Sondas de DNA/genética , DNA de Cadeia Simples/genética , Desoxirribonuclease IV (Fago T4-Induzido)/química , Feminino , Corantes Fluorescentes/química , Humanos , Limite de Detecção , Medições Luminescentes/métodos , Conformação de Ácido Nucleico , Hibridização de Ácido Nucleico , Neoplasias Ovarianas/genética , Mutação Puntual , Telomerase/genética
11.
Gynecol Oncol ; 154(2): 345-353, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31242966

RESUMO

OBJECTIVE: Cervical HR-HPV persistence is the main risk factor for cervical cancer. We aimed to investigate the association of age and viral factors with HR-HPV persistence. METHODS: From 2010 to 2017, 343,128 women underwent 390,411 tests performed by the Cervista HR-HPV assay (Data C3) and 157,123 women underwent 206,505 tests performed by the GenoArray HR-HPV assay (Data G14) in nine medical centers located in central and eastern China. We combined the test results and identified 9234 HPV-specific baseline-negative records for time-to-event analyses. The study endpoint event was defined as clearance of type/group-specific HPV. Therefore, hazard ratio (HR) < 1 indicated a higher risk of HPV persistence, which is contrary to the common meaning of HR. RESULTS: The median persistence time was 375 and 541.5 days for Data C3 and Data G14, respectively. For every 5-year increase in age, a 15% (95% confidence interval [CI], 11%-19%) decrease in the clearance rate was observed only after 400 days of infection. For each additional co-infected HPV, the HR was 1.80 (95% CI, 1.63-1.97) on infection initiation but decreased by 22% (95% CI, 18%-26%) every 100 days. The HR of infection recurrence was 0.48 (95% CI, 0.32-0.72). The findings were consistent across different populations and test methods and were robust in sensitivity analysis. CONCLUSIONS: We found a time-dependent association of age and viral factors with HPV clearance. Older age reduced HPV clearance only after 400 days of infection. Co-infection promoted HPV clearance in the beginning, but the effect attenuated and reversed as infection persisted. Recurrent same-type infection cleared slower than the previous one.


Assuntos
Papillomaviridae/fisiologia , Infecções por Papillomavirus/virologia , Adulto , Fatores Etários , Idoso , Neoplasia Intraepitelial Cervical/virologia , China , Feminino , Seguimentos , Humanos , Programas de Rastreamento/estatística & dados numéricos , Pessoa de Meia-Idade , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/epidemiologia , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Tempo , Neoplasias do Colo do Útero/virologia
12.
Cell ; 178(1): 176-189.e15, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31155231

RESUMO

RLR-mediated type I IFN production plays a pivotal role in elevating host immunity for viral clearance and cancer immune surveillance. Here, we report that glycolysis, which is inactivated during RLR activation, serves as a barrier to impede type I IFN production upon RLR activation. RLR-triggered MAVS-RIG-I recognition hijacks hexokinase binding to MAVS, leading to the impairment of hexokinase mitochondria localization and activation. Lactate serves as a key metabolite responsible for glycolysis-mediated RLR signaling inhibition by directly binding to MAVS transmembrane (TM) domain and preventing MAVS aggregation. Notably, lactate restoration reverses increased IFN production caused by lactate deficiency. Using pharmacological and genetic approaches, we show that lactate reduction by lactate dehydrogenase A (LDHA) inactivation heightens type I IFN production to protect mice from viral infection. Our study establishes a critical role of glycolysis-derived lactate in limiting RLR signaling and identifies MAVS as a direct sensor of lactate, which functions to connect energy metabolism and innate immunity.

13.
J Hematol Oncol ; 12(1): 58, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31182108

RESUMO

Among all malignant tumors that threaten human health, virus-related tumors account for a large proportion. The treatment of these tumors is still an urgent problem to be resolved. The immune system is the "guard" of the human body, resisting the invasion of foreign substances such as viruses. Studies have shown that immunotherapy has clinical significance in the treatment of a variety of tumors. In particular, the emergence of immune checkpoint inhibitors (ICIs) in recent years has opened a new door to cancer therapy. Considering the potential role of ICIs in the treatment of virus-related cancers, we focused on their therapeutic effect in virus-associated cancers and explored whether the therapeutic effect in virus-associated cancers was related to virus infection status. Although there is no clear statistical significance indicates that ICIs are more effective in virus-associated cancers than non-virus infections, the efficacy of checkpoint inhibitors in the treatment of virus-related cancers is promising. We believe that this research provides a good direction for the implementation of individualized precision medicine.

14.
Nanomedicine (Lond) ; 14(5): 613-626, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30816057

RESUMO

AIM: To investigate the influence of tissue mechanics on the cellular uptake efficiency of nanoparticles (NPs) in cancer. MATERIALS & METHODS: Collagen-coated polyacrylamide gels were prepared as model substrates. Coumarin 6-loaded poly(lactic-co-glycolic) acid micelles (C6-NPs) were prepared to investigate the cellular uptake of NPs. RESULTS: We demonstrated that substrate stiffness modulated the cellular uptake of NPs of cancer. Mechanistically, mechanical cues exerted influence on the clathrin-mediated endocytosis and caveolae-mediated endocytosis pathways, which mediated stiffness-regulated cellular uptake of NPs. CONCLUSION: Our findings shed light on the regulatory role of the mechanical cues on the cellular uptake of NPs and will facilitate the selection of clinical patients who might benefit from a given nanotherapy.


Assuntos
Cavéolas/metabolismo , Clatrina/metabolismo , Células A549 , Resinas Acrílicas/química , Animais , Western Blotting , Linhagem Celular Tumoral , Endocitose/fisiologia , Feminino , Células HeLa , Humanos , Camundongos , Nanopartículas/química
15.
J Exp Med ; 216(3): 688-703, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30710055

RESUMO

High-grade serous ovarian cancer (HGSOC) is hallmarked by early onset of peritoneal dissemination, which distinguishes it from low-grade serous ovarian cancer (LGSOC). Here, we describe the aggressive nature of HGSOC ascitic tumor cells (ATCs) characterized by integrin α5high (ITGA5high) ATCs, which are prone to forming heterotypic spheroids with fibroblasts. We term these aggregates as metastatic units (MUs) in HGSOC for their advantageous metastatic capacity and active involvement in early peritoneal dissemination. Intriguingly, fibroblasts inside MUs support ATC survival and guide their peritoneal invasion before becoming essential components of the tumor stroma in newly formed metastases. Cancer-associated fibroblasts (CAFs) recruit ITGA5high ATCs to form MUs, which further sustain ATC ITGA5 expression by EGF secretion. Notably, LGSOC is largely devoid of CAFs and the resultant MUs, which might explain its metastatic delay. These findings identify a specialized MU architecture that amplifies the tumor-stroma interaction and promotes transcoelomic metastasis in HGSOC, providing the basis for stromal fibroblast-oriented interventions in hampering OC peritoneal propagation.

16.
Sci Rep ; 9(1): 1691, 2019 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-30737418

RESUMO

Ovarian carcinoma is caused by multiple factors, but its etiology associated with microbes and infection is unknown. Using 16S rRNA high-throughput sequencing methods, the diversity and composition of the microbiota from ovarian cancer tissues (25 samples) and normal distal fallopian tube tissues (25 samples) were analyzed. High-throughput sequencing showed that the diversity and richness indexes were significantly decreased in ovarian cancer tissues compared to tissues from normal distal fallopian tubes. The ratio of the two phyla for Proteobacteria/Firmicutes was notably increased in ovarian cancer, which revealed that microbial composition change might be associated with the process of ovarian cancer development. In addition, transcriptome-sequencing (RNA-seq) analyses suggested that the transcriptional profiles were statistically different between ovarian carcinoma and normal distal fallopian tubes. Moreover, a set of genes including 84 different inflammation-associated or immune-associated genes, which had been named as the human antibacterial-response genes were also modulated expression. Therefore, we hypothesize that the microbial composition change, as a novel risk factor, may be involving the initiation and progression of ovarian cancer via influencing and regulating the local immune microenvironment of fallopian tubes except for regular pathways.

17.
Nat Cell Biol ; 21(2): 214-225, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30692626

RESUMO

The serine/threonine kinase Akt plays a central role in cell proliferation, survival and metabolism, and its hyperactivation is linked to cancer progression. Here we report that Akt undergoes K64 methylation by SETDB1, which is crucial for cell membrane recruitment, phosphorylation and activation of Akt following growth factor stimulation. Furthermore, we reveal an adaptor function of histone demethylase JMJD2A, which is important for recognizing Akt K64 methylation and recruits E3 ligase TRAF6 and Skp2-SCF to the Akt complex, independently of its demethylase activity, thereby initiating K63-linked ubiquitination, cell membrane recruitment and activation of Akt. Notably, the cancer-associated Akt mutant E17K displays enhanced K64 methylation, leading to its hyper-phosphorylation and activation. SETDB1-mediated Akt K64 methylation is upregulated and correlated with Akt hyperactivation in non-small-cell lung carcinoma (NSCLC), promotes tumour development and predicts poor outcome. Collectively, these findings reveal complicated layers of Akt activation regulation coordinated by SETDB1-mediated Akt K64 methylation to drive tumorigenesis.


Assuntos
Carcinogênese/metabolismo , Metiltransferases de Proteína/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ubiquitinação , Células A549 , Animais , Carcinogênese/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Feminino , Células HEK293 , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Lisina/genética , Lisina/metabolismo , Metilação , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Camundongos Nus , Células NIH 3T3 , Metiltransferases de Proteína/genética , Proteínas Proto-Oncogênicas c-akt/genética , Transplante Heterólogo
18.
EBioMedicine ; 40: 92-105, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30674441

RESUMO

BACKGROUND: Ubiquinol-cytochrome C reductase core protein II (QCR2) is essential for mitochondrial functions, yet, its role in cancer development has remained elusive. METHODS: The expression of QCR2 in cancer patients was assessed by immunohistochemistry. The proliferation of cancer cells was assessed by CCK-8 assay, EdU staining and Flow cytometry analysis. The biological function of QCR2 and PHB were determined using western blotting, RT-qPCR, microarray analysis and xenografts. The interactions between proteins and the ubiquitination of p53 were assessed by immunoprecipitation, mass spectrometry analysis and GST pull down. The subcellular location of PHB and QCR2 was assessed by immunoblotting and immunofluorescence. FINDING: The expression of QCR2 is upregulated in multiple human tumors. Suppression of QCR2 inhibits cancer cell growth by activating p53 signaling and inducing p21-dependent cell cycle arrest and senescence. QCR2 directly interacts with PHB in the mitochondria. Overexpression of QCR2 inhibits PHB binding to p53 in the nucleus, and facilitates p53 ubiquitination and degradation, consequently leading to tumorigenesis. Also, increased QCR2 and decreased PHB protein levels are well correlated with decreased expression of p21 in cervical cancer tissues. INTERPRETATION: These results identify a novel role for QCR2, together with PHB, in negative regulation of p53 stability and activity, thus promote cervical carcinogenesis. FUND: "973" Program of China, the National Science-technology Supporting Plan Projects, the National Natural Science Foundation of China, National Science and Technology Major Sub-Project and Technical Innovation Special Project of Hubei Province.


Assuntos
Transformação Celular Neoplásica/metabolismo , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/genética , Senescência Celular/genética , Complexo III da Cadeia de Transporte de Elétrons/genética , Feminino , Expressão Gênica , Técnicas de Silenciamento de Genes , Inativação Gênica , Humanos , Imuno-Histoquímica , Camundongos , Modelos Biológicos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Ligação Proteica , Proteólise , Ubiquitinação
19.
Mol Cancer ; 17(1): 172, 2018 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-30541550

RESUMO

BACKGROUND: Cellular senescence is a state of irreversible cell growth arrest and senescence cells permanently lose proliferation potential. Induction of cellular senescence might be a novel therapy for cancer cells. TRIB2 has been reported to participate in regulating proliferation and drug resistance of various cancer cells. However, the role of TRIB2 in cellular senescence of colorectal cancer (CRC) and its molecular mechanism remains unclear. METHODS: The expression of TRIB2 in colorectal cancer tissues and adjacent tissues was detected by immunohistochemistry and RT-PCR. The growth, cell cycle distribution and cellular senescence of colorectal cancer cells were evaluated by Cell Counting Kit-8 (CCK8) assay, flow cytometry detection and senescence-associated ß-galactosidase staining, respectively. Western blot, RT-PCR and luciferase assay were performed to determine how TRIB2 regulates p21. Immunoprecipitation (IP) and chromatin-immunoprecipitation (ChIP) were used to investigate the molecular mechanisms. RESULTS: We found that TRIB2 expression was elevated in CRC tissues compared to normal adjacent tissues and high TRIB2 expression indicated poor prognosis of CRC patients. Functionally, depletion of TRIB2 inhibited cancer cells proliferation, induced cell cycle arrest and promoted cellular senescence, whereas overexpression of TRIB2 accelerated cell growth, cell cycle progression and blocked cellular senescence. Further studies showed that TRIB2 physically interacted with AP4 and inhibited p21 expression through enhancing transcription activities of AP4. The rescue experiments indicated that silencing of AP4 abrogated the inhibition of cellular senescence induced by TRIB2 overexpression. CONCLUSION: These data demonstrate that TRIB2 suppresses cellular senescence through interaction with AP4 to down-regulate p21 expression. Therefore, TRIB2 could be a potential target for CRC treatment.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Neoplasias Colorretais/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Oncogenes/genética , Transdução de Sinais/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Ciclo Celular/genética , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular , Proliferação de Células/genética , Senescência Celular/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo
20.
Cell Death Dis ; 10(1): 9, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30584257

RESUMO

Mounting evidence has demonstrated that angiogenesis plays an important role in tumour progression. However, the key regulators in tumour angiogenesis remain unclear. Recently, emerging reports have indicated that SIRT2 plays critical roles in proliferation, metastasis and tumourigenesis in diverse tumours. However, the function of SIRT2 in tumour angiogenesis and the mechanism underlying the regulation of angiogenesis by SIRT2 are still unknown. Here, we found that SIRT2 was upregulated in colorectal cancer tissues compared to that in normal samples and that the elevated SIRT2 was associated with poor prognosis in patients with colorectal cancer. In addition, a series of in vitro and in vivo experiments were performed to demonstrate the role of SIRT2 in tumour angiogenesis. We showed that silencing SIRT2 significantly suppressed tumour angiogenesis. Mechanistically, the knockdown of SIRT2 inhibited STAT3 phosphorylation, causing decreased secretion of VEGFA. Notably, we found that SIRT2 directly interacted with STAT3 and affected the phosphorylation of STAT3 and the translocation of phosphorylated STAT3 to the nucleus. Importantly, a series of rescue experiments suggested that the function of SIRT2 in tumour angiogenesis depends on the STAT3/VEGFA signalling pathway. Our findings provide insight into the important role of SIRT2 in colon tumour angiogenesis and suggest that SIRT2/STAT3/VEGFA might be a novel prognostic biomarker and a potential therapeutic target for patients with colorectal cancer.

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