scholarly journals EP1 receptor is involved in prostaglandin E2-induced osteosarcoma growth

Author(s):  
Jing-cai Niu ◽  
Nan Ma ◽  
Wei Liu ◽  
Pei-ji Wang

Recent studies showed that the activation of prostaglandin (PG) receptor EP1 promotes cell migration and invasion in different cancers. The aim of this study was to investigate the role of EP1 in the proliferation of osteosarcoma (OS) cells in vitro and in vivo. EP1 mRNA and protein levels were analyzed by real-time RT-PCR and Western blot, respectively in human OS cell lines MG63, OS732, U-2OS, HOS and SAOS-2 compared to human fetal osteoblastic hFOB 1.19 cells. MG63 cells were treated with PGE2, EP1 specific agonist 17-PT-PGE2, 17-PT-PGE2 + EP1 specific antagonist SC51089, or DMSO (control). EP1R-siRNA or a non-silencing irrelevant RNA duplex (negative control) were used for the transfection of MG63 cells, followed by PGE2 treatment. Nude mice carrying MG63 xenografts were treated with SC51089 (2 mg/kg/day). MG63 cells/xenografts were analyzed by MTT assay, TUNEL assay, PKC enzyme activity assay, and Western blot (EP1 and apoptotic proteins), and tumor growth/volume was evaluated in mice. EP1 levels were significantly higher in OS cells compared to osteoblasts. PGE2 or 17-PT-PGE2 treatment increased the proliferation and decreased the apoptosis of MG63 cells. Inhibition of EP1 by SC51089 or siRNA markedly decreased the viability of MG63 cells. Similarly, SC51089 treatment significantly inhibited MG63 cell proliferation and promoted apoptosis in vivo. The silencing of EP1 receptor by siRNA or blockade of EP1 signaling by SC51089 activated extrinsic and intrinsic apoptotic pathways both in vivo and in vitro, as evidenced by increased levels of Bax, cyt-c, cleaved caspase-3, caspase-8 and caspase-9. EP1 appears to be involved in PGE2-induced proliferative activity of MG63 cells. Antagonizing EP1 may provide a novel therapeutic approach to the treatment of OS.

2020 ◽  
Vol 19 (17) ◽  
pp. 2108-2119
Author(s):  
Yang Jin ◽  
Li Lv ◽  
Shu-Xiang Ning ◽  
Ji-Hong Wang ◽  
Rong Xiao

Background: Laryngeal Squamous Cell Carcinoma (LSCC) is a malignant epithelial tumor with poor prognosis and its incidence rate increased recently. rLj-RGD3, a recombinant protein cloned from the buccal gland of Lampetra japonica, contains three RGD motifs that could bind to integrins on the tumor cells. Methods: MTT assay was used to detect the inhibitory rate of viability. Giemsa’s staining assay was used to observe the morphological changes of cells. Hoechst 33258 and TUNEL staining assay, DNA ladder assay were used to examine the apoptotic. Western blot assay was applied to detect the change of the integrin signal pathway. Wound-healing assay, migration, and invasion assay were used to detect the mobility of Hep2 cells. H&E staining assay was used to show the arrangement of the Hep2 cells in the solid tumor tissues. Results: In the present study, rLj-RGD3 was shown to inhibit the viability of LSCC Hep2 cells in vitro by inducing apoptosis with an IC50 of 1.23µM. Western blot showed that the apoptosis of Hep2 cells induced by rLj- RGD3 was dependent on the integrin-FAK-Akt pathway. Wound healing, transwells, and western blot assays in vitro showed that rLj-RGD3 suppressed the migration and invasion of Hep2 cells by integrin-FAKpaxillin/ PLC pathway which could also affect the cytoskeleton arrangement in Hep2 cells. In in vivo studies, rLj-RGD3 inhibited the growth, tumor volume, and weight, as well as disturbed the tissue structure of the solid tumors in xenograft models of BALB/c nude mice without reducing their body weights. Conclusion: hese results suggested that rLj-RGD3 is an effective and safe suppressor on the growth and metastasis of LSCC Hep2 cells from both in vitro and in vivo experiments. rLj-RGD3 might be expected to become a novel anti-tumor drug to treat LSCC patients in the near future.


2017 ◽  
Vol 42 (3) ◽  
pp. 1025-1036 ◽  
Author(s):  
Dehu Chen ◽  
Guiyuan Liu ◽  
Ning Xu ◽  
Xiaolan You ◽  
Haihua Zhou ◽  
...  

Background/Aims: Gastric cancer (GC) is a common and lethal malignancy, and AMP-activated protein kinase-related kinase 5 (ARK5) has been discovered to promote cancer metastasis in certain types of cancer. In this study, we explored the role of ARK5 in GC invasion and metastasis. Methods: ARK5 and epithelial-mesenchymal transition (EMT)-related markers were determined by immunohistochemistry and western blot in GC specimens. Other methods including stably transfected against ARK5 into SGC7901 and AGS cells, western blot, migration and invasion assays in vitro and nude mice tumorigenicity in vivo were also employed. Results: The results demonstrated that ARK5 expression was increased and positively correlated with metastasis, EMT-related markers and poor prognosis in patients with GC. Knockdown of ARK5 expression remarkably suppressed GC cells invasion and metastasis via regulating EMT, rather than proliferation in vitro and in vivo. And knockdown of ARK5 expression in GC cells resulted in the down-regulation of the mTOR/p70S6k signals, Slug and SIP1. Conclusion: The elevated ARK5 expression was closely associated with cancer metastasis and patient survival, and it seemed to function in GC cells migration and invasion via EMT alteration, together with the alteration of the mTOR/p70S6k signals, Slug and SIP1, thus providing a potential therapeutic target for GC.


Author(s):  
Jialing Wen ◽  
Xianglin Liu ◽  
Yan Qi ◽  
Feng Niu ◽  
Zhitong Niu ◽  
...  

Abstract Background BMP3 gene is often found hypermethylated and hence inactivated in several types of cancers including colorectal cancer (CRC), indicating that it has a suppressor role in carcinogenesis. Though BMP3 is a reliable biomarker for screening CRC, the molecular mechanism of BMP3 in carcinogenesis remains largely unknown. Methods The expression level of BMP3 was examined by immunohistochemistry staining and western blot. Methylation-specific PCR (MSP) and real-time quantitative MSP were used to test the hypermethylation status of BMP3 gene. Analyses of BMP3 function in colon cancer cell proliferation, migration, invasion, and apoptosis were performed using HCT116 and KM12 cells. BMP3 was further knocked down or overexpressed in CRC cells, and the effects on cell growth of xenograft tumors in nude mice were assessed. Co-immunoprecipitation and immunofluorescence staining were used to analyze the association between BMP3 and BMPR2 or BMP3 and ActRIIB. Microarray analysis was performed to identify most differentially expressed genes and pathways regulated by BMP3. The BMP3-regulated SMAD2-dependent signaling pathway and TAK1/JNK signal axes were further investigated by quantitative PCR and western blot. Results BMP3 gene was hypermethylated and its expression was downregulated in both CRC tissues and cell lines. Expressing exogenous BMP3 in HCT116 inhibited cell growth, migration, and invasion and increased rate of apoptosis both in vitro and in vivo. However, shRNA-mediated attenuation of endogenous BMP3 in KM12 reversed such inhibitory and apoptotic effects. Furthermore, BMP3 could bind to ActRIIB, an activin type II receptor at the cellular membrane, thereby activating SMAD2-dependent pathway and TAK1/JNK signal axes to regulate downstream targets including caspase-7, p21, and SMAD4 that play crucial roles in cell cycle control and apoptosis. Conclusions Our study reveals a previously unknown mechanism of BMP3 tumor suppression in CRC and provides a rationale for future investigation of BMP3 as a potential target for the development of novel therapeutic agents to fight CRC.


2017 ◽  
Vol 44 (1) ◽  
pp. 255-266 ◽  
Author(s):  
Jinjin Liu ◽  
Jun Rao ◽  
Xuming Lou ◽  
Jian Zhai ◽  
Zhenhua Ni ◽  
...  

Background/Aims: The tripartite motif containing (TRIM) family plays crucial roles in tumor development and progression. However, little is known about the function and mechanism of TRIM11 in hepatocellular carcinoma (HCC). Methods: The expression levels of TRIM11 were examined by real-time PCR, Western blot and Immunohistochemical (IHC) staining. TRIM11 knockdown cells were produced by lentivirus infection, and functional assays, such as MTT, colony formation assay, migration and invasion assays and a xenograft tumor model were used to investigate the role of TRIM11 in HCC. We also determined the effect of TRIM11 on p53 signaling and its downstream molecules. Results: We found that TRIM11 mRNA and protein levels were significantly increased in HCC tissues as compared with normal tissues; increased levels correlated with poor patient survival. By loss- and gain-of-function investigations, knockdown of TRIM11 suppressed cell proliferation, migration, invasion in vitro and tumor growth in vivo. Moreover, TRIM11 negatively regulated p53 expression. Knockdown of p53 abrogated the in vitro and in vivo biological functions of TRIM11 shRNA in HCC cells. Conclusions: These data show that TRIM11 exerts its oncogenic effect in HCC by downregulating p53 both in vitro and in vivo. Our data provide new insights into the pathogenesis of HCC and indicate that TRIM11 may serve as a new therapeutic target for HCC treatment.


2019 ◽  
Vol 37 (15_suppl) ◽  
pp. e15554-e15554
Author(s):  
Yanyan Chi ◽  
Feng Wang ◽  
Xiangrui Meng ◽  
Zhengzheng Shan ◽  
Yan Sun ◽  
...  

e15554 Background: Apatinib, a highly selective inhibitor of vascular endothelial growth factor receptor-2 (VEGFR-2), inhibits the angiogenesis of tumors. The function and mechanism of Apatinib in esophageal squamous cell carcinoma (ESCC) remains unknown. Methods: The expression of VEGFR-2 in ESCC cell lines (KYSE450, EC1, KYSE410, KYSE70) were detected by western blot. KYSE450 and EC1 cell lines were treated with Apatinib, or combined with cytotoxic drugs: paclitaxel (TAX), 5-fluorouracil (5-FU) or cisplatin (DDP) respectively. Cell proliferation was then measured using CCK-8 assay; cell apoptosis was analyzed by flow cytometry; cell migration and invasion were evaluated by wound healing and transwell assays. The expression of VEGFR-2, Bcl2, MMP-2/MMP-9, p-Akt and p-mTOR in KYSE450 and EC1 cell lines were determined by western blot. Esophageal cancer xenografts model was established and used to evaluate the antitumor effects of combination of Apatinib and cytotoxic drugs in vivo. Immunohistochemistry was used to detect the expression of Ki67, VEGFR-2 and CD31 in tumor tissues of esophageal cancer xenografts model. Results: We found that Apatinib efficiently inhibited cell growth, metastasis and activity of the Akt/mTOR pathway in ESCC cells. Western blot analysis showed that Apatinib significantly increased Bax protein levels, decreased VEGFR-2, Bcl2, MMP-2/MMP-9, p-Akt and p-mTOR protein levels in ESCC cells. Moreover, Apatinib enhanced chemosensitivity of cytotoxic drugs TAX, 5-FU and DDP by upregulating expression of Bax protein, and downregulating expression of VEGFR-2, Bcl2, MMP-2/MMP-9 protein in vitro. Compared with single agent groups, the combination of Apatinib with each chemotherapeutic drug significantly repressed tumor growth and angiogenesis through blocking the expression of Ki67, VEGFR-2 and CD31 in vivo. Conclusions: Taken together, Apatinib suppressed cell growth, migration and invasion, and promoted antitumor effect of chemotherapeutic agents in ESCC.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Zechen Zhao ◽  
Weiming Chu ◽  
Yang Zheng ◽  
Chao Wang ◽  
Yuemei Yang ◽  
...  

Abstract Background Eukaryotic translation initiation factor 6 (eIF6), also known as integrin β4 binding protein, is involved in ribosome formation and mRNA translation, acting as an anti-association factor. It is also essential for the growth and reproduction of cells, including tumor cells. Yet, its role in oral squamous cell carcinoma (OSCC) remains unclear. Methods The expression characteristics of eIF6 in 233 samples were comprehensively analyzed by immunohistochemical staining (IHC). Effects of eIF6 over-expression and knockdown on cell proliferation, migration and invasion were determined by CCK-8, wound healing and Transwell assays. Western blot, immunofluorescence (IF) and co-immunoprecipitation (co-IP) were performed for mechanical verification. Results We found that cytoplasmic eIF6 was abnormally highly expressed in OSCC tissues, and its expression was associated with tumor size and the clinical grade. Amplification of eIF6 promoted the growth, migration and invasion capabilities of OSCC cell lines in vitro and tumor growth in vivo. Through Western blot analysis, we further discovered that eIF6 significantly promotes epithelial-mesenchymal transformation (EMT) in OSCC cells, while depletion of eIF6 can reverse this process. Mechanistically, eIF6 promoted tumor progression by activating the AKT signaling pathway. By performing co-immunoprecipitation, we discovered a direct interaction between endogenous eIF6 and AKT protein in the cytoplasm. Conclusion These results demonstrated that eIF6 could be a new therapeutic target in OSCC, thus providing a new basis for the prognosis of OSCC patients in the future.


2021 ◽  
Author(s):  
Wenpeng Cao ◽  
Zhirui Zeng ◽  
Runsang Pan ◽  
Zhiwei He ◽  
Hao Wu ◽  
...  

Abstract Background: Hypoxia participated in the occurrence and development of pancreatic cancer (PC). However, genes associated with hypoxia respond and their regulated mechanism in PC cells were unclear. The current research was aimed to illuminate the role and hypoxia regulated mechanism of fucosyltransferase 11 (FUT11) in the progression of PC.Methods: After predicting FUT11 as a key hypoxia associated gene in PC using bioinformatics analysis. The expression of FUT11 in PC using quantitative real-time fluorescent PCR, western blot and immunohistochemistry. The effects of FUT11 on PC cells proliferation, migration and invasion under normoxia and hypoxia were detected using Cell Counting Kit 8, 5-ethynyl-2’-deoxyuridine assay, colony formation assay and transwell assay. Spleen capsule injected liver metastasis and subcutaneously injected model were performed to confirm the effects of FUT11 in vivo. Furthermore, western blot, luciferase assay and immunoprecipitation were performed to explore the regulated relationship among FUT11, hypoxia-inducible factor 1α (HIF1α) and pyruvate dehydrogenase kinase 1 (PDK1) in PC.Results: FUT11 was markedly increased of PC cells in hypoxia, up-regulated in the PC clinical tissues, and predicted a poor outcome. Inhibition of FUT11 reduced PC cell growth and mobility of PC cells under normoxia and hypoxia conditions in vitro, and growth and mobility in vivo. FUT11 bind with PDK1 and regulated the expression PDK1 under normoxia and hypoxia. FUT11 knockdown significantly increased the degradation rate of PDK1 under hypoxia, while treatment with MG132 can relieve the degradation of PDK1 induced by FUT11 knockdown. Overexpression of PDK1 in PC cells under hypoxia conditions reversed the suppressiv impacts of FUT11 knockdown on PC cell growth and mobility. In addition, HIF1α bound to the enhancer of FUT11 and increased its expression, as well as co-expressing with FUT11 in PC tissues. Furthermore, overexpress of FUT11 partially rescued the suppressiv effects of HIF1α knockdown on PC cell growth and mobility in hypoxia conditions.Conclusion: Our data further implicate that hypoxia-induced FUT11 in PC contributes to proliferation and metastasis by maintaining the stability of PDK1, and suggest FUT11 maybe a novel and effective target for treatment of pancreatic cancer.


2018 ◽  
Vol 51 (4) ◽  
pp. 1799-1814 ◽  
Author(s):  
Cong-cong Jia ◽  
Juan Du ◽  
Xia Liu ◽  
Rui Jiang ◽  
Yongye Huang ◽  
...  

Background/Aims: B-cell receptor-associated protein 31 (Bap31) is an evolutionarily conserved, ubiquitously expressed, polytopic integral membrane protein in the endoplasmic reticulum (ER) that is involved in the regulation of apoptosis, protein transport and degradation. Patients with Bap31 mutations exhibit symptoms similar to those exhibited by patients with central nervous system (CNS) diseases, such as deafness, dystonia, and intellectual disability. The present study aimed to investigate the function of Bap31 in CNS diseases by identifying a CNS disease-related gene regulated by Bap31 and exploring the underlying molecular mechanism. Methods: ShRNA-Bap31 and siRNA-Bap31 were used to knockdown Bap31 in N2a cells, and real-time PCR was performed to detect the mRNA levels of genes involved in CNS diseases. Western blot analyses were used to examine the protein levels of the candidate gene (valosin-containing protein, VCP) both in vivo and in vitro. The functions of Bap31 and VCP in mediating the degradation of the hyper-unstable mutant of cystic fibrosis trans-membrane conductance regulator (CFTRΔF508) were studied. Moreover, real-time PCR, Western blot and dual luciferase reporter analyses were conducted to investigate the molecular mechanism by which Bap31 regulates the expression levels of VCP. Results: VCP was identified as a candidate gene based on its differential expression in N2a cells following both shRNA- and siRNA-mediated knockdown of Bap31. Both the mRNA and protein levels of VCP were regulated by Bap31 in vivo and in vitro. In the ER-associated degradation (ERAD) pathway, Bap31 also regulated VCP expression and caused differences in the binding quantities of CFTRΔF508 and VCP. Furthermore, a transcription factor of VCP (E74-like factor 2, Elf2) was regulated by Bap31, and Elf2 mediated the changes in VCP transcription and expression in cells with altered Bap31 expression. Conclusion: These results indicate that Bap31 regulates the expression of VCP possibly via Elf2 and support the potential molecular function of Bap31 in CNS diseases.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 5198-5198
Author(s):  
Ping Liu ◽  
Dan Ma ◽  
Jishi Wang

Background: Acute lymphoblastic leukaemia (ALL) is one of the most common clonal malignant diseases in children, and it stems from unchecked proliferation of lymphoid progenitor cells. Glucocorticoids (GCs) such as prednisolone and dexamethasone are used as a chemotherapeutic drug in the treatment of ALL. GC-induced cell mortality is first mediated by the activation of glucocorticoid receptor (GR), followed by its translocation into the nucleus to activate or inhibit gene transcription. However, up to ~20% patients with leukemia relapse and become resistant to GCs. Therefore, a better understanding the molecular basis of chemoresistance in ALL would provide novel therapeutic opportunities for patients. Methods: By analyzing the published mRNA expression profiles (GSE5280; GSE94302) obtained from NCBI (https://www.ncbi.nlm.nih.gov/geo/), we found that higher expression of ANXA1 was significantly associated with decreased overall survival of ALL patients. We also examined the expression of ANXA1 at mRNA and protein levels in a variety of ALL cell lines by using qRT-PCR and western blot analyses. The mRNA and protein expression of ANXA1 in ALL cell lines and patients were determined using Real-time PCR and Western blot respectively. Functional assays, such as CCK-8, FACS, and Tunel assay used to determine the oncogenic role of ANXA1 in ALL progression. Furthermore, western blotting and luciferase assay were used to determine the mechanism of ANXA1 promotes chemoresistance in ALL cells. Results: The expression of ANXA1 was markedly upregulated in ALL cell lines and patients, and high ANXA1 expression was associated with relapsed/refractory ALL patients. ANXA1 overexpression confers glucocorticoids (GCs) resistance on ALL cells; however, down-regulated of ANXA1 sensitized ALL cell lines to GC both in vitro and in vivo. Additionally, ANXA1 upregulated the levels of FPRs by promoting Wnt/β-catenin signalling. Conclusions: Our findings provided evidence that ANXA1 is a potential therapeutic target for patients with ALL. Targeting ANXA1 signaling may be a promising strategy to enhance GC response during ALL chemo-resistance. Disclosures No relevant conflicts of interest to declare.


2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii167-ii167
Author(s):  
Lili Sun ◽  
Ming Li

Abstract The four and a half LIM domain 1 (FHL1) has been considered as a tumor suppressor protein in multiple cancers. Here, we show that FHL1 plays a tumor-promoting role in glioblastoma, the most common and incurable brain cancer. Overexpression of FHL1 promotes the growth, migration, and invasion of GBM cells in vivo and in vitro. In contrast, FHL1 silencing exhibits the opposite effects. Mechanically, FHL1 upregulates EGFR expression and activates the downstream AKT / ERK1 / 2 / STAT3 signaling pathways. We further demonstrated that SP1 can also be induced by FHL1 expression, and FHL1 interacts with SP1 to upregulate EGFR expression at both mRNA and protein levels, leading to glioblastoma malignancy. Clinically, FHL1 is highly expressed in glioblastoma and shows positive correlation with EGFR and SP1 in GBM specimens. Our results suggest the key role of FHL1 in the expression of EGFR and highlight the translation potential of inhibiting FHL1 as a treatment for glioblastoma.


Sign in / Sign up

Export Citation Format

Share Document