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1.
Beneficial effects of metformin on cancer risk and mortality have been proved by epidemiological and clinical studies, thus attracting research interest in elucidating the underlying mechanisms. Recently, tumour‐associated macrophages (TAMs) appeared to be implicated in metformin‐induced antitumour activities. However, how metformin inhibits TAMs‐induced tumour progression remains ill‐defined. Here, we report that metformin‐induced antitumour and anti‐angiogenic activities were not or only partially contributed by its direct inhibition of functions of tumour and endothelial cells. By skewing TAM polarization from M2‐ to M1‐like phenotype, metformin inhibited both tumour growth and angiogenesis. Depletion of TAMs by clodronate liposomes eliminated M2‐TAMs‐induced angiogenic promotion, while also abrogating M1‐TAMs‐mediated anti‐angiogenesis, thus promoting angiogenesis in tumours from metformin treatment mice. Further in vitro experiments using TAMs‐conditioned medium and a coculture system were performed, which demonstrated an inhibitory effect of metformin on endothelial sprouting and tumour cell proliferation promoted by M2‐polarized RAW264.7 macrophages. Based on these results, metformin‐induced inhibition of tumour growth and angiogenesis is greatly contributed by skewing of TAMs polarization in microenvironment, thus offering therapeutic opportunities for metformin in cancer treatment.  相似文献   

2.
Caspase‐3 is a critical effector caspase in apoptosis cascade, and is often over‐expressed in many cancer tissues. The first synthesized procaspase‐3 activator, PAC‐1, induces cancer cell apoptosis and exhibits antitumour activity in murine xenograft models. To identify more potent procaspase‐3 activators, a series of compounds were designed, synthesized and evaluated for their ability of inducing cancer cell death in culture. Among these compounds, WF‐208 stood out by its high cytotoxicity against procaspase‐3 overexpressed HL‐60 cells. Compared with PAC‐1, WF‐208 showed higher cytotoxicity in cancer cells and lower toxicity in normal cells. The further investigation described herein showed that WF‐208 activated procaspase‐3, degraded IAPs (The Inhibitors of apoptosis proteins) and leaded to caspase‐3‐dependent cell death in tumour cells, which possibly because of the zinc‐chelating properties. WF‐208 also showed greater antitumour activity than PAC‐1 in murine xenograft model. In conclusion, we have discovered WF‐208 as a promising procaspase‐3 activating compound, with higher activity and higher cell selectivity than PAC‐1.  相似文献   

3.
Overexpression of P2X7R has been observed in several tumours and is related to cancer advancement and metastasis. However, the role of P2X7R in colorectal cancer (CRC) patients is not well understood. In the current study, overexpression of P2X7R and the effects at the molecular and functional levels in CRC were assessed in a mouse orthotopic model. Functional assays, such as the CCK‐8 assay, wound healing and transwell assay, were used to determine the biological role of P2X7R in CRC cells. CSC‐related genes and properties were detected via sphere formation and real‐time PCR assays. The underlying mechanisms were explored by Western blotting, real‐time PCR and Flow cytometry. In this study, we found that overexpression of P2X7R increases in the in vivo growth of tumours. P2X7R overexpression also increased CD31, VEGF and concurrent angiogenesis. P2X7R up‐regulates aldehyde dehydrogenase‐1 (ALDH1) and CSC characteristics. Transplanted tumour cells with P2X7R overexpression stimulated cytokines to recruit tumour‐associated macrophage (TAMs) to increase the growth of tumours. We also found that the NF‐κB signalling pathway is involved in P2X7R‐induced cytokine up‐regulation. P2X7R promotes NF‐κB–dependent cytokine induction, which leads to TAM recruitment to control tumour growth and advancement and remodelling of the stroma. Our findings demonstrate that P2X7R plays a key role in TAM recruitment, which may be a therapeutic target for CRC patients.  相似文献   

4.
Tumour‐associated macrophage (TAM) is an important component in tumour microenvironment. Generally, TAM exhibits the function of M2‐like macrophage, which was closely related to angiogenesis and tumour progression. Dioscin, a natural steroidal saponin, has shown its powerful anti‐tumour activity recently. However, the mechanism of dioscin involved in immune regulation is still obscure. Here, we observed dioscin induced macrophage M2‐to‐M1 phenotype transition in vitro and inhibited IL‐10 secretion. Meanwhile, the phagocytosis of macrophages was enhanced. In subcutaneous lung tumour models, dioscin inhibited the augmentation of M2 macrophage populations. Furthermore, dioscin down‐regulated STAT3 and JNK signalling pathways in macrophages in vitro. In BMDMs, activating JNK and inhibiting STAT3 induce macrophages to M1 polarization while inhibiting JNK and activating STAT3 to M2 polarization. Additionally, condition mediums from dioscin‐pre‐treated macrophages inhibited the migration of 3LL cells and the tube‐formation capacity of HUVECs. What's more, dioscin‐mediated macrophage polarization inhibited the in vivo metastasis of 3LL cells. In conclusion, dioscin may act as a new anti‐tumour agent by inhibiting TAMs via JNK and STAT3 pathways in lung cancer.  相似文献   

5.
This study explored the effects involved in silencing CLIC4 on apoptosis and proliferation of mouse liver cancer Hca‐F and Hca‐P cells. A CLIC4‐target small interfering RNA (siRNA) was designed to compound into two individual complementary oligonucleotide chains. A process of annealing and connection to a pSilencer vector was followed by transfection with Hca‐F and Hca‐P cells. Quantitative real‐time polymerase chain reaction and Western blotting techniques were used to determine CLIC4 mRNA and protein expressions. CCK8 assay and flow cytometry were employed for analysis of the survival and apoptosis rate as well as the cell cycle in an octreotide‐induced apoptosis model. Expressions of caspase 3, caspase 9, and cleaved PARP were measured using Western blotting. The CLIC4 mRNA and protein expressions in Hca‐F and Hca‐P cells transfected by pSilencer‐CLIC4 siRNA plasmid in the blank group displayed remarkably decreased levels of expression, when compared with both the control and negative control (NC) groups. Decreased survival rates and cleaved PARP expression, increased cell apoptosis rate,expressions of caspase 3 and caspase 9 in Hca‐F and Hca‐P cells were detected in groups that had been cultured in a medium containing octreotide. The pSilencer‐CLIC4 siRNA‐2 group when compared with the control and NC groups exhibited decreased survival rates, cleaved PARP expression, increased cell apoptosis rates, and increased expressions of caspase 3 and caspase 9 of Hca‐F and Hca‐P cells. The results demonstrated that siRNA‐induced down‐regulation of CLIC4 could proliferation, while in turn promoting apoptosis of mouse liver cancer Hca‐F and Hca‐P cells. J. Cell. Biochem. 119: 659–668, 2018. © 2017 Wiley Periodicals, Inc.  相似文献   

6.
7.
Hepatocellular carcinoma (HCC) is the sixth most common malignancy with limited treatment options. Hinokiflavone (HF), a natural biflavonoid, has shown to inhibit the proliferation of melanoma, whereas its antitumour effect against HCC and the underlying mechanisms remain elusive. Here, we aimed at evaluating its antitumour effect against HCC in both in vitro and in vivo. Cell counting kit 8, colony formation assay, PI/RNase staining and Western blotting revealed that HF inhibited the proliferation of HCC cells via G0/G1 cell cycle arrest with p21/p53 up‐regulation. DAPI staining, Annexin V‐FITC/PI staining and Western blotting confirmed that HF triggered caspase‐dependent apoptosis. Moreover, HF increased the levels of mitochondrial reactive oxygen species (mtROS) and activated c‐Jun N‐terminal kinase (JNK) pathway, as measured by MitoSOX Red staining and Western blotting. After respectively inhibiting mtROS (Mito‐TEMPO) and JNK (SP600125), HF‐induced apoptosis was reversed. Additionally, Western blotting documented that HF suppressed nuclear factor kappa B (NF‐κB) activity and the anti‐apoptotic genes downstream, contributing to cell apoptosis. Finally, in vivo studies demonstrated that HF significantly impaired tumour growth in HCC xenograft. Collectively, these findings suggested that HF induced apoptosis through activating mtROS/JNK/caspase pathway and inhibiting NF‐κB signalling, which may represent a novel therapeutic agent for treating HCC.  相似文献   

8.
Vitamin C is generally thought to enhance immunity and is widely taken as a supplement especially during cancer treatment. Tamoxifen (TAM) has both cytostatic and cytotoxic properties for breast cancer. TAM engaged mitochondrial oestrogen receptor beta in MCF‐7 cells and induces apoptosis by activation of pro‐caspase‐8 followed by downstream events, including an increase in reactive oxygen species and the release of pro‐apoptotic factors from the mitochondria. In addition to that, TAM binds with high affinity to the microsomal anti‐oestrogen‐binding site and inhibits cholesterol esterification at therapeutic doses. This study aimed to investigate the role of vitamin C in TAM‐mediated apoptosis. Cells were loaded with vitamin C by exposure to dehydroascorbic acid, thereby circumventing in vitro artefacts associated with the poor transport and pro‐oxidant effects of ascorbic acid. Pre‐treatment with vitamin C caused a dose‐dependent attenuation of cytotoxicity, as measured by acridine‐orange/propidium iodide (AO/PI) and Annexin V assay after treatment with TAM. Vitamin C dose‐dependently protected cancer cells against lipid peroxidation caused by TAM treatment. By real‐time PCR analysis, an impressive increase in FasL and tumour necrosis factor‐α (TNF‐α) mRNA was detected after TAM treatment. In addition, a decrease in mitochondrial transmembrane potential was observed. These results support the hypothesis that vitamin C supplementation during cancer treatment may detrimentally affect therapeutic response.  相似文献   

9.
Tumour‐associated macrophages (TAMs) represent pivotal components of tumour microenvironment promoting angiogenesis, tumour progression and invasion. In colorectal cancer (CRC), there are no conclusive data about the role of TAMs in angiogenesis‐mediated tumour progression. In this study, we aimed to evaluate a correlation between TAMs, TAM immunostained area (TAMIA) microvascular density (MVD), endothelial area (EA) and cancer cells positive to VEGF‐A (CCP‐VEGF‐A) in primary tumour tissue of locally advanced CRC patients undergone to radical surgery. A series of 76 patients with CRC were selected and evaluated by immunohistochemistry and image analysis. An anti‐CD68 antibody was employed to assess TAMs and TAMIA expression, an anti‐CD34 antibody was utilized to detect MVD and EA expression, whereas an anti‐VEGF‐A antibody was used to detect CCP‐VEGF‐A; then, tumour sections were evaluated by image analysis methods. The mean ± S.D. of TAMs, MVD and CCP‐VEGF‐A was 65.58 ± 21.14, 28.53 ± 7.75 and 63% ± 37%, respectively; the mean ± S.D. of TAMIA and EA was 438.37 ± 124.14μ2 and 186.73 ± 67.22μ2, respectively. A significant correlation was found between TAMs, TAMIA, MVD and EA each other (r ranging from 0.69 to 0.84; P ranging from 0.000 to 0.004). The high level of expression of TAMs and TAMIA in tumour tissue and the significant correlation with both MVD and EA illustrate that TAMs could represent a marker that plays an important role in promoting angiogenesis‐mediated CRC. In this context, novel agents killing TAMs might be evaluated in clinical trials as a new anti‐angiogenic approach.  相似文献   

10.
Immature myeloid cells including myeloid‐derived suppressor cells (MDSCs) and tumour‐associated macrophages (TAMs) promote tumour growth and metastasis by facilitating tumour transformation and angiogenesis, as well as by suppressing antitumour effector immune responses. Therefore, strategies designed to reduce MDSCs and TAMs accumulation and their activities are potentially valuable therapeutic goals. In this study, we show that negative immune checkpoint molecule B7‐H3 is significantly overexpressed in human head and neck squamous cell carcinoma (HNSCC) specimen as compared with normal oral mucosa. Using immunocompetent transgenic HNSCC models, we observed that targeting inhibition of B7‐H3 reduced tumour size. Flow cytometry analysis revealed that targeting inhibition of B7‐H3 increases antitumour immune response by decreasing immunosuppressive cells and promoting cytotoxic T cell activation in both tumour microenvironment and macroenvironment. Our study provides direct in vivo evidence for a rationale for B7‐H3 blockade as a future therapeutic strategy to treat patients with HNSCC.  相似文献   

11.
SARI (suppressor of AP‐1, regulated by IFN) impaired tumour growth by promoting apoptosis and inhibiting cell proliferation and tumour angiogenesis in various cancers. However, the role of SARI in regulating tumour‐associated inflammation microenvironment is still elusive. In our study, the colitis‐dependent and ‐independent primary model were established in SARI deficiency mice and immuno‐reconstructive mice to investigate the functional role of SARI in regulating tumour‐associated inflammation microenvironment and primary colon cancer formation. The results have shown that SARI deficiency promotes colitis‐associated cancer (CAC) development only in the presence of colon inflammation. SARI inhibited tumour‐associated macrophages (TAM) infiltration in colon tissues, and SARI deficiency in bone marrow cells has no observed role in the promotion of intestinal tumorigenesis. Mechanism investigations indicated that SARI down‐regulates p‐STAT1 and STAT1 expression in colon cancer cells, following inhibition of MCP‐1/CCR2 axis activation during CAC development. Inverse correlations between SARI expression and macrophage infiltration, MCP‐1 expression and p‐STAT1 expression were also demonstrated in colon malignant tissues. Collectively, our results prove the inhibition role of SARI in colon cancer formation through regulating TAM infiltration.  相似文献   

12.
Accumulation of tumor‐associated macrophages (TAMs) associates with malignant progression in cancer. However, the mechanisms that drive the pro‐tumor functions of TAMs are not fully understood. ZEB1 is best known for driving an epithelial‐to‐mesenchymal transition (EMT) in cancer cells to promote tumor progression. However, a role for ZEB1 in macrophages and TAMs has not been studied. Here we describe that TAMs require ZEB1 for their tumor‐promoting and chemotherapy resistance functions in a mouse model of ovarian cancer. Only TAMs that expressed full levels of Zeb1 accelerated tumor growth. Mechanistically, ZEB1 expression in TAMs induced their polarization toward an F4/80low pro‐tumor phenotype, including direct activation of Ccr2. In turn, expression of ZEB1 by TAMs induced Ccl2, Cd74, and a mesenchymal/stem‐like phenotype in cancer cells. In human ovarian carcinomas, TAM infiltration and CCR2 expression correlated with ZEB1 in tumor cells, where along with CCL2 and CD74 determined poorer prognosis. Importantly, ZEB1 in TAMs was a factor of poorer survival in human ovarian carcinomas. These data establish ZEB1 as a key factor in the tumor microenvironment and for maintaining TAMs’ tumor‐promoting functions.  相似文献   

13.
Sip1/tuftelin‐interacting protein (STIP), a multidomain nuclear protein, is a novel factor associated with the spliceosome, yet its role and molecular function in cancer remain unknown. In this study, we show, for the first time, that STIP is overexpressed in non‐small cell lung cancer (NSCLC) tissues compared to adjacent normal lung tissues. The depletion of endogenous STIP inhibited NSCLC cell proliferation in vitro and in vivo, caused cell cycle arrest and induced apoptosis. Cell cycle arrest at the G2/M phase was associated with the expression and activity of the cyclin B1‐CDK1 (cyclin‐dependent kinase 1) complex. We also provide evidence that STIP knockdown induced apoptosis by activating both caspase‐9 and caspase‐3 and by altering the Bcl‐2/Bax expression ratio. RNA sequencing data indicated that the MAPK mitogen‐activated protein kinases, Wnt, PI3K/AKT, and NF‐κB (nuclear factor kappa‐light‐chain‐enhancer of activated B cells) signalling pathways might be involved in STIP‐mediated tumour regulation. Collectively, these results suggest that STIP may be a novel potential diagnostic and therapeutic target for NSCLC.  相似文献   

14.
Corilagin is a component of Phyllanthus urinaria extract and has been found of possessing anti‐inflammatory, anti‐oxidative, and anti‐tumour properties in clinic treatments. However, the underlying mechanisms in anti‐cancer particularly of its induction of cell death in human breast cancer remain undefined. Our research found that corilagin‐induced apoptotic and autophagic cell death depending on reactive oxygen species (ROS) in human breast cancer cell, and it occurred in human breast cancer cell (MCF‐7) only comparing with normal cells. The expression of procaspase‐8, procaspase‐3, PARP, Bcl‐2 and procaspase‐9 was down‐regulated while caspase‐8, cleaved PARP, caspase‐9 and Bax were up‐regulated after corilagin treatment, indicating apoptosis mediated by extrinsic and mitochondrial pathways occurred in MCF‐7 cell. Meanwhile, autophagy mediated by suppressing Akt/mTOR/p70S6K pathway was detected with an increase in autophagic vacuoles and LC3‐II conversion. More significantly, inhibition of autophagy by chloroquine diphosphate salt (CQ) remarkably enhanced apoptosis, while the caspase inhibitor z‐VAD‐fmk failed in affecting autophagy, suggesting that corilagin‐induced autophagy functioned as a survival mechanism in MCF‐7 cells. In addition, corilagin induced intracellular reactive oxygen species (ROS) generation, when reduced by ROS scavenger NAC, apoptosis and autophagy were both down‐regulated. Nevertheless, in SK‐BR3 cell which expressed RIP3, necroptosis inhibitor Nec‐1 could not alleviate cell death induced by corilagin, indicating necroptosis was not triggered. Subcutaneous tumour growth in nude mice was attenuated by corilagin, consisting with the results in vitro. These results imply that corilagin inhibits cancer cell proliferation through inducing apoptosis and autophagy which regulated by ROS release.  相似文献   

15.
16.
Hepatocellular carcinoma (HCC) is the third leading cause of the cancer‐related death in the world. Human amniotic mesenchymal stem cells (hAMSCs) have been characterized with a pluripotency, low immunogenicity and no tumorigenicity. Especially, the immunosuppressive and anti‐inflammatory effects of hAMSCs make them suitable for treating HCC. Here, we reported that hAMSCs administrated by intravenous injection significantly inhibited HCC through suppressing cell proliferation and inducing cell apoptosis in tumour‐bearing mice with Hepg2 cells. Cell tracking experiments with GFP‐labelled hAMSCs showed that the stem cells possessed the ability of migrating to the tumorigenic sites for suppressing tumour growth. Importantly, both hAMSCs and the conditional media (hAMSC‐CM) have the similar antitumour effects in vitro, suggesting that hAMSCs‐derived cytokines might be involved in their antitumour effects. Antibody array assay showed that hAMSCs highly expressed dickkopf‐3 (DKK‐3), dickkopf‐1 (DKK‐1) and insulin‐like growth factor‐binding protein 3 (IGFBP‐3). Furthermore, the antitumour effects of hAMSCs were further confirmed by applications of the antibodies or the specific siRNAs of DKK‐3, DKK‐1 and IGFBP‐3 in vitro. Mechanically, hAMSCs‐derived DKK‐3, DKK‐1 and IGFBP‐3 markedly inhibited cell proliferation and promoted apoptosis of Hepg2 cells through suppressing the Wnt/β‐catenin signalling pathway and IGF‐1R‐mediated PI3K/AKT signalling pathway, respectively. Taken together, our study demonstrated that hAMSCs possess significant antitumour effects in vivo and in vitro and might provide a novel strategy for HCC treatment clinically.  相似文献   

17.
Disabled‐1 (Dab1) is best known as an adaptor protein regulating neuron migration and lamination during development. However, the exact function of Dab1 in breast cancer is unknown. In this study, we examined the expression of Dab1 in 38 breast cancer paraffin sections, as well as 60 paired frozen breast cancer and their adjacent tissues. Our results showed that Dab1 was reduced in breast cancer, and its compromised expression correlated with triple negative breast cancer phenotype, poor differentiation, as well as lymph node metastasis. Functional analysis in breast cancer cell lines demonstrated that Dab1 promoted cell apoptosis, which, at least partially, depended on its regulation of NF‐κB/Bcl‐2/caspase‐9 pathway. Our study strongly suggests that Dab1 may be a potential tumour suppressor gene in breast cancer.  相似文献   

18.
Targeting the androgen receptor (AR) signalling pathway remains the main therapeutic option for advanced prostate cancer. However, resistance to AR‐targeting inhibitors represents a great challenge, highlighting the need for new therapies. Activation of the PI3K/AKT pathway and increased expression of histone deacetylases (HDACs) are common aberrations in prostate cancer, suggesting that inhibition of such targets may be a viable therapeutic strategy for this patient population. Previous reports demonstrated that combination of PI3K inhibitors (PI3KIs) with histone deacetylase inhibitors (HDACIs) resulted in synergistic antitumour activities against preclinical models of prostate cancer. In this study, we demonstrate that the novel dual PI3K and HDAC inhibitor CUDC‐907 has promising antitumour activity against prostate cancer cell lines in vitro and castration‐resistant LuCaP 35CR patient‐derived xenograft (PDX) mouse model in vivo. CUDC‐907‐induced apoptosis was partially dependent on Mcl‐1, Bcl‐xL, Bim and c‐Myc. Further, down‐regulation of Wee1, CHK1, RRM1 and RRM2 contributed to CUDC‐907‐induced DNA damage and apoptosis. In the LuCaP 35CR PDX model, treatment with CUDC‐907 resulted in significant inhibition of tumour growth. These findings support the clinical development of CUDC‐907 for the treatment of prostate cancer.  相似文献   

19.
Despite the low efficacy of conventional antitumour drugs, chemotherapy remains an essential tool in controlling advanced gastric and oesophageal cancers. We aimed to provide a biological rationale based on the sorafenib–taxotere interaction for the clinical treatment of gastric cancer. In vitro experiments were performed on four human gastric cancer cell lines (GK2, AKG, KKP and NCI‐N87). Cytotoxicity was evaluated by sulforhodamine B (SRB) assay, cell cycle perturbations, apoptosis and mitotic catastrophe were assessed by flow cytometric and microscopic analyses, and protein expression was studied by Western blot. In the in vivo experiments, nude mice xenografted with the most resistant line were treated with sorafenib and docetaxel singly or in association. Sorafenib inhibited cell growth (IG50 values ranged from 3.4 to 8.1 μM) and caused down‐regulation of MAP‐K/ERK phosphorylation and of mcl‐1 and p‐bad expression after a 48‐hr exposure. Apoptosis induction was associated with caspase‐3 and ‐9 activation and mitochondrial membrane depolarization. The drug combination enhanced apoptosis (up to 80%) and produced a synergistic interaction when low doses of the taxane preceded administration of the antityrosine kinase. This synergism was probably due to the induction of an anomalous multidiploid G0‐G1 peak and to consequent mitotic catastrophe, which increased sensitivity to sorafenib. Consistent with in vitro results, the docetaxel–sorafenib sequence exhibited high therapeutic efficacy in NCI‐N87 mouse xenografts producing tumour weight inhibition (> 65%), tumour growth delay (up to 25 days) and increased mouse survival (30%). Our findings suggest the potential clinical usefulness of treatment with sorafenib and docetaxel for advanced gastric cancer.  相似文献   

20.
Lestaurtinib, also called CEP‐701, is an inhibitor of tyrosine kinase, causes haematological remission in patients with AML possessing FLT3‐ITD (FLT3 gene) internal tandem duplication and strongly inhibits tyrosine kinase FLT3. Treatment with lestaurtinib modulates various signalling pathways and leads to cell growth arrest and programmed cell death in several tumour types. However, the effect of lestaurtinib on glioma remains unclear. In this study, we examined lestaurtinib and TRAIL interactions in glioma cells and observed their synergistic activity on glioma cell apoptosis. While U87 and U251 cells showed resistance to TRAIL single treatment, they were sensitized to apoptosis induced by TRAIL in the presence of lestaurtinib because of increased death receptor 5 (DR5) levels through CHOP‐dependent manner. We also demonstrated using a xenograft model of mouse that the tumour growth was absolutely suppressed because of the combined treatment compared to TRAIL or lestaurtinib treatment carried out singly. Our findings reveal a potential new strategy to improve antitumour activity induced by TRAIL in glioma cells using lestaurtinib through a mechanism dependent on CHOP.  相似文献   

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