scholarly journals TGF-β protects osteosarcoma cells from chemotherapeutic cytotoxicity in a SDH/HIF1α dependent manner

BMC Cancer ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Yangbo Xu ◽  
Yafei Li ◽  
Xiaofan Chen ◽  
Feifan Xiang ◽  
Yong Deng ◽  
...  
Keyword(s):  
Chemotherapy Resistance ◽  
Metabolite Profile ◽  
Chemotherapeutic Agents ◽  
Metabolic Energy ◽  
Dependent Manner ◽  
Osteosarcoma Cells ◽  
Succinate Production ◽  
Anticancer Efficacy ◽  
Cell Extracts

Abstract Background In the widespread adoption of chemotherapy, drug resistance has been the major obstacle to tumor elimination in cancer patients. Our aim was to explore the role of TGF-β in osteosarcoma-associated chemoresistance. Methods We performed a cytotoxicity analysis of methotrexate (MTX) and cisplatin (CIS) in TGF-β-treated osteosarcoma cells. Then, the metabolite profile of the core metabolic energy pathways in Saos-2 and MG-63 cell extracts was analyzed by 1H-NMR. We detected the expression of succinate dehydrogenase (SDH), STAT1, and hypoxia-inducible factor 1α (HIF1α) in TGF-β-treated osteosarcoma cells and further tested the effects of these molecules on the cytotoxicity induced by chemotherapeutic agents. Using in vivo experiments, we examined the tumor growth and survival time of Saos-2-bearing mice treated with a combination of chemotherapeutic agents and a HIF1α inhibitor. Results The metabolic analysis revealed enhanced succinate production in osteosarcoma cells after TGF-β treatment. We further found a decrease in SDH expression and an increase in HIF1α expression in TGF-β-treated osteosarcoma cells. Consistently, blockade of SDH efficiently enhanced the resistance of Saos-2 and MG-63 cells to MTX and CIS. Additionally, a HIF1α inhibitor significantly strengthened the anticancer efficacy of the chemotherapeutic drugs in mice with osteosarcoma cancer. Conclusion Our study demonstrated that TGF-β attenuated the expression of SDH by reducing the transcription factor STAT1. The reduction in SDH then caused the upregulation of HIF1α, thereby rerouting glucose metabolism and aggravating chemoresistance in osteosarcoma cells. Linking tumor cell metabolism to the formation of chemotherapy resistance, our study may guide the development of additional treatments for osteosarcoma.

scholarly journals TGF-β Suppressed Succinat Dehydrogenase to Promote Osteosarcoma Chemo-Resistance Through An HIF1α Dependent Manner

2021 ◽  
Author(s):  
Yangbo Xu ◽  
Yafei Li ◽  
Feifan Xiang ◽  
Yong Deng ◽  
Zhong Li ◽  
...  
Keyword(s):  
Cell Metabolism ◽  
Hypoxia Inducible Factor ◽  
Chemotherapy Resistance ◽  
Metabolite Profile ◽  
Chemotherapeutic Agents ◽  
Dependent Manner ◽  
Osteosarcoma Cells ◽  
Succinate Production ◽  
Cell Extracts

Abstract Background：Despite the widespread adoption of chemotherapy, drug resistance has been the major obstacle in tumor elimination of cancer patients. Our aim was to explore the role of TGF-β in osteosarcoma chemo-resistance. Methods：We performed cytotoxicity analysis of methotrexate (MTX) and cisplatin (CIS) in TGF-β treated osteosarcoma cells. Then a metabolite profile of the core energetic routes was analyzed by 1H-NMR in Saos-2 and MG-63 cell extracts. We detected the expression of succinate dehydrogenase (SDH), STAT1, and Hypoxia-inducible factor 1α (HIF1α) in TGF-β treated osteosarcoma cells, and further tested the effects of these molecules on the cytotoxicity of chemotherapeutic agents. In vivo, we examined the tumor growth and survival time of Saos-2 bearing mice given the combination therapy of chemotherapeutic agents and a HIF1α inhibitor. Results：Metabolic analysis revealed an enhanced succinate production of osteosarcoma cells after TGF-β treatment. We further found the decrease in SDH expression and the increase in HIF1α expression of TGF-β treated osteosarcoma cells. Consistently, blockade of SDH aggravated the resistance of Saos-2/MG-63 cells to MTX and CIS. Also, a HIF1α inhibitor significantly strengthened the anti-cancer efficacy of chemotherapeutic drugs in mice with osteosarcoma cancer.Conclusion：Our study demonstrated that TGF-β attenuated the expression of SDH through reducing the transcription factor STAT1. The reduction of SDH then caused the up-regulation of HIF1α, thereby rerouting the glucose metabolism and aggravating chemo-resistance in osteosarcoma cells. Linking tumor cell metabolism to the formation of chemotherapy resistance, our study may guide the development of more effective treatments of osteosarcoma.

scholarly journals HDAC6 inhibitor WT161 performs antitumor effect on osteosarcoma and synergistically interacts with 5-FU

2021 ◽  
Author(s):  
Jun Sun ◽  
Wei Wu ◽  
Xiaofeng Tang ◽  
Feifei Zhang ◽  
Cheng Ju ◽  
...  
Keyword(s):  
Dependent Manner ◽  
Osteosarcoma Cells ◽  
Synergistic Inhibition ◽  
Proliferative Effect ◽  
Xenograft Models ◽  
Hdac6 Inhibitor ◽  
Underlying Mechanisms ◽  
Induced Apoptosis

Background: WT161, as a selective HDAC6 inhibitor, has been shown to play anti-tumor effects on several kinds of cancers. The aim of this study is to explore the roles of WT161 in osteosarcoma and its underlying mechanisms. Methods: The anti-proliferative effect of WT161 on osteosarcoma cells was examined using MTT assay and colony formation assay. Cell apoptosis was analyzed using flow cytometer. The synergistic effect was evaluated by isobologram analysis using CompuSyn software. The osteosarcoma xenograft models were established to evaluate the anti-proliferative effect of WT161 in vivo. Results: WT161 suppressed the cell growth and induced apoptosis of osteosarcoma cells in a dose- and time-dependent manner. Mechanistically, we found that WT161 treatment obviously increased the protein level of PTEN and decreased the phosphorylation level of AKT. More importantly, WT161 show synergistic inhibition with 5-FU on osteosarcoma cells in vitro and in vivo. Conclusions: These results indicate that WT161 inhibits the growth of osteosarcoma through PTEN and has a synergistic efficiency with 5-FU.

scholarly journals HDAC6 Inhibitor WT161 Performs Antitumor Effect on Ostersarcoma and Synergistically Interacts with 5-FU

2020 ◽  
Author(s):  
Jun Sun ◽  
Xiaofeng Tang ◽  
Feifei Zhang ◽  
Cheng Ju ◽  
Renfeng Liu ◽  
...  
Keyword(s):  
Osteosarcoma Cell ◽  
Dependent Manner ◽  
Osteosarcoma Cells ◽  
Proliferative Effect ◽  
Xenograft Models ◽  
Hdac6 Inhibitor ◽  
Underlying Mechanisms ◽  
Induced Apoptosis

Abstract Background: WT161 as a new selective HDAC6 inhibitor has been shown to play anti-tumor effects on multiple myeloma and breast cancer. However, the role of WT161 in osteosarcoma remains unclear. The aim of this study is to explore the role of WT161 in osteosarcoma and its underlying mechanisms.Methods: The anti-proliferative effect of WT161 on osteosarcoma cells was examined using MTT assay and colony formation assay. Cell apoptosis was analyzed using flow cytometer. The synergistic effect was evaluated by isobologram analysis using CompuSyn software. The osteosarcoma xenograft models were esatablished to evaluate the anti-proliferative effect of WT161 in vivo.Results: WT161 suppressed the cell growth and induced apoptosis of osteosarcoma cells in a dose- and time-dependent manner. Mechanistically, we found that WT161 treatment obviously increased the protein expression level of PTEN and decreased the phosphorylation level of AKT. Notably, WT161 shows synergistically inhibitory effects on osteosarcoma cell combined with 5-FU. Animal experiment results show WT161 inhibits the growth of osteosarcoma tumor and further illustrates that WT161 and 5-FU have a synergistic efficiency in osteosarcoma.Conclusions: These results indicate that WT161 inhibiting the growth of osteosarcoma through PTEN and has a synergistic efficiency with 5-FU.

SECRETION OF A BONE-INDUCING AGENT (BIA) BY CULTURED SAOS-2 HUMAN OSTEOSARCOMA CELLS

1999 ◽  
Vol 03 (01) ◽  
pp. 39-48 ◽  
Author(s):  
H. C. Anderson ◽  
D. J. Gurley ◽  
H. H. T. Hsu ◽  
X. M. Aguilera ◽  
L. S. Davis ◽  
...  
Keyword(s):  
Conditioned Medium ◽  
Culture Medium ◽  
Osteosarcoma Cells ◽  
Western Blots ◽  
Serum Free ◽  
Human Osteosarcoma ◽  
Cell Extracts ◽  
Human Osteosarcoma Cells ◽  
Freeze Dried

An extractable bone-inducing agent has recently been identified in freeze-dried preparations of Saos-2 cultured human osteosarcoma cells. Although not all osteoinductive components of Saos-2 cell extracts have been identified, we have shown that Saos-2 cells express high levels of mRNA for bone morphogenetic proteins (BMPs)-1,2,3,4 and 6. Any or all of these BMPs (plus possible unknown factors) may be involved in ectopic bone induction, and may act as paracrine agents, conveying morphogenetic information to juxtaposed osteoprogenitor cells. Our objectives in this study were: 1) to determine whether Saos-2 cells secrete BIA into their culture medium; and 2) if secreted, to determine whether released bone-inducing agent is soluble and/or particulate and contains BMPs. Saos-2 cells were grown to confluence, and then overlaid with serum-free DMEM culture medium for 48 hours. The serum-free conditioned medium was then decanted and filtered through 0.45μ pore-size filters to retain any vesicles or other particulates released by the cells. Particulate protein retained on the 0.45μ filter (designated "retentate") was extracted into 6M urea and bioassayed for bone-inducing activity in Nu/Nu mice, along with soluble media protein that had passed through the 0.45μ filter (designated "filtrate") plus freeze-dried Saos-2 cells from which conditioned the culture medium was obtained. Results indicate that the bone-inducing agent of Saos-2 cells is not only retained by the cells, but is also secreted in both soluble and particulate forms into serum-free conditioned medium. Bone-inducing activity (per mg protein) is more concentrated in the particulate fraction, which is shown by electron microscopy to contain a mixture of vesicles (similar to matrix vesicles) plus electron dense granules (resembling ribosomes) and 10 mM microfilaments (of possible collagenous or cytoskeletal origin). BMP-1,2,3,4,6 and 7 were detected by western blots in both the soluble and particulate fractions of conditioned medium. Thus, it is indicated that Saos-2 cells secrete an osteoinductive factor which may function in vivo as a paracrine morphogenetic agent.

scholarly journals Cinobufagin Induces Apoptosis in Osteosarcoma Cells Via the Mitochondria-Mediated Apoptotic Pathway

2018 ◽  
Vol 46 (3) ◽  
pp. 1134-1147 ◽  
Author(s):  
Guo Dai ◽  
Di Zheng ◽  
Weichun Guo ◽  
Jian Yang ◽  
An-yuan Cheng
Keyword(s):  
Cell Apoptosis ◽  
Xenograft Model ◽  
Childhood And Adolescence ◽  
Osteosarcoma Cell ◽  
Dependent Manner ◽  
Osteosarcoma Cells ◽  
Apoptosis Pathway ◽  
Subcutaneous Xenograft ◽  
Induced Apoptosis

Background/Aims: Osteosarcoma is a common primary malignant bone tumor that mainly occurs in childhood and adolescence. Despite developments in the diagnosis and treatment of osteosarcoma, the prognosis is still very poor. Cinobufagin is an active component in the anti-tumor Chinese medicine called “Chan Su”, and we previously revealed that cinobufagin induced apoptosis and reduced the viability of osteosarcoma cells; however, the underlying mechanism remains to be elucidated. Herein, the present study was undertaken to illuminate the molecular mechanism of cinobufagin-induced apoptosis of osteosarcoma cell. Methods: U2OS and 143B cells were treated with different concentrations of cinobufagin. Cell viability, colony formation ability and morphological changes were assessed by a CCK-8 assay, a clonogenic assay and light microscopy, respectively. Cell apoptosis was detected by Hoechst 33258 and Annexin V-FITC/PI staining. Reactive oxygen species (ROS) and mitochondrial membrane potential (ΔΨm) were determined by flow cytometry. Glutathione (GSH) levels were detected by a GSH and GSSG assay kit. The levels of apoptosis-related proteins were determined by western blotting, and 143B cells were introduced to establish a xenograft tumor model. The effect of cinobufagin on osteosarcoma was further investigated in vivo. Results: Our results showed that cinobufagin significantly reduced the viability of U2OS and 143B cells in vitro in a dose-and time-dependent manner. In addition, cinobufagin-induced apoptosis in U2OS and 143B cells was concentration-dependent. Moreover, we found that cinobufagin treatment increased the level of intracellular ROS, decreased ΔΨm, reduced GSH and inhibited GSH reductase (GR). The effects of cinobufagin on cell proliferation, apoptosis, ROS generation and ΔΨm loss were dramatically reversed when the cells were pretreated with the thiol-antioxidants NAC or GSH. Moreover, cinobufagin treatment increased the expression of the pro-apoptotic protein Bax and decreased the expression of the anti-apoptitic protein Bcl-2, thus altering the ratio of Bax to Bcl-2. Furthermore, Cinobufagin treatment caused cytochrome c release from the mitochondria to cytoplasm, thus increasing the protein levels of cleaved-caspase family members to induce apoptosis. Ac-DEVD-CHO or Z-LEHD-FMK significantly reduced cinobufagin-induced apoptosis. Finally, a subcutaneous xenograft animal study verified that cinobufagin also significantly suppressed osteosarcoma growth in vivo. Conclusions: Our present data demonstrated that cinobufagin triggered cell apoptosis in osteosarcoma cells via the intrinsic mitochondria-dependent apoptosis pathway by the accumulation of ROS and the loss of ΔΨm. In an in vivo subcutaneous xenograft model, cinobufagin exhibited excellent tumor inhibitory effects. These results suggest that cinobufagin might potentially be further developed as an anti-tumor candidate for treating osteosarcoma patients in the clinic.

scholarly journals The REGγ inhibitor NIP30 increases sensitivity to chemotherapy in p53-deficient tumor cells

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Xiao Gao ◽  
Qingwei Wang ◽  
Ying Wang ◽  
Jiang Liu ◽  
Shuang Liu ◽  
...  
Keyword(s):  
Chemotherapy Resistance ◽  
Inhibitory Effect ◽  
Chemotherapeutic Agents ◽  
Serine Phosphorylation ◽  
Cancer Cell Growth ◽  
Rich Domain ◽  
Novel Approach ◽  
Growth Inhibitory

Abstract A major challenge in chemotherapy is chemotherapy resistance in cells lacking p53. Here we demonstrate that NIP30, an inhibitor of the oncogenic REGγ-proteasome, attenuates cancer cell growth and sensitizes p53-compromised cells to chemotherapeutic agents. NIP30 acts by binding to REGγ via an evolutionarily-conserved serine-rich domain with 4-serine phosphorylation. We find the cyclin-dependent phosphatase CDC25A is a key regulator for NIP30 phosphorylation and modulation of REGγ activity during the cell cycle or after DNA damage. We validate CDC25A-NIP30-REGγ mediated regulation of the REGγ target protein p21 in vivo using p53−/− and p53/REGγ double-deficient mice. Moreover, Phosphor-NIP30 mimetics significantly increase the growth inhibitory effect of chemotherapeutic agents in vitro and in vivo. Given that NIP30 is frequently mutated in the TCGA cancer database, our results provide insight into the regulatory pathway controlling the REGγ-proteasome in carcinogenesis and offer a novel approach to drug-resistant cancer therapy.

Anti-Proliferative Efficacy of Icariin on HepG2 Hepatoma and Its Possible Mechanism of Action

2009 ◽  
Vol 37 (06) ◽  
pp. 1153-1165 ◽  
Author(s):  
Jin-Xia Yang ◽  
Iduna Fichtner ◽  
Monika Becker ◽  
Margit Lemm ◽  
Xue-Mei Wang
Keyword(s):  
Bone Marrow ◽  
Mechanism Of Action ◽  
Mtt Assay ◽  
Control Group ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Anticancer Efficacy ◽  
Cd8 Cells

The aim of the present work was to explore the anti-hepatoma effects of icariin both in vitro and in vivo and to elucidate its potential mechanism of action. The MTT assay was applied to test the anti-proliferative effects of icariin in vitro. HepG2 bearing NMRI nu/nu mice were used to test the anticancer effects of icariin in vivo. Immunohistochemical assay and flow cytometry assay (FACS) were applied to detect the possible mechanisms of action of icariin. MTT assay illustrated that icariin inhibited the proliferation of HepG2 cells in a concentration dependent manner; meanwhile, icariin inhibited the tumor growth in HepG2 bearing NMRI nu/nu mice. The tumor weight was inhibited by 55.6% and tumor volume was inhibited by 47.2%. Icariin did not influence the spleen and body weights or blood parameters. Immunohistochemical analysis indicated that the expressions of both CD31 and Ki67 in the icariin treated group were significantly lower than those in the control group (p < 0.01). FACS assay showed that icariin dramatically decreased the percentage of CD4+ and CD8+ cells in bone marrow and CD19+ cells in blood on day 8. On day 17, the percentage of CD8+ cells in blood was lower than those in the control group. CD4/CD8 ratio in icariin group was significantly elevated in bone marrow on day 17. Icariin showed anticancer efficacy both in vitro and in vivo. The possible mechanism of action could be related to its anti-angiogenesis and anti-proliferative effects in tumors.

C-terminal domain phosphorylation of ERK3 controlled by Cdk1 and Cdc14 regulates its stability in mitosis

2010 ◽  
Vol 428 (1) ◽  
pp. 103-111 ◽  
Author(s):  
Pierre-Luc Tanguay ◽  
Geneviève Rodier ◽  
Sylvain Meloche
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Progression ◽  
Mitotic Cell ◽  
Mitogen Activated Protein Kinase ◽  
Phosphorylation Sites ◽  
Dependent Manner ◽  
Cell Extracts ◽  
Cycle Dependent

ERK3 (extracellular-signal-regulated kinase 3) is an atypical MAPK (mitogen-activated protein kinase) that is suggested to play a role in cell-cycle progression and cellular differentiation. However, it is not known whether the function of ERK3 is regulated during the cell cycle. In the present paper, we report that ERK3 is stoichiometrically hyperphosphorylated during entry into mitosis and is dephosphorylated at the M→G1 transition. The phosphorylation of ERK3 is associated with the accumulation of the protein in mitosis. In vitro phosphorylation of a series of ERK3-deletion mutants by mitotic cell extracts revealed that phosphorylation is confined to the unique C-terminal extension of the protein. Using MS analysis, we identified four novel phosphorylation sites, Ser684, Ser688, Thr698 and Ser705, located at the extreme C-terminus of ERK3. All four sites are followed by a proline residue. We have shown that purified cyclin B-Cdk1 (cyclindependent kinase 1) phosphorylates these sites in vitro and demonstrate that Cdk1 acts as a major Thr698 kinase in vivo. Reciprocally, we found that the phosphatases Cdc14A and Cdc14B (Cdc is cell-division cycle) bind to ERK3 and reverse its C-terminal phosphorylation in mitosis. Importantly, alanine substitution of the four C-terminal phosphorylation sites markedly decreased the half-life of ERK3 in mitosis, thereby linking phosphorylation to the stabilization of the kinase. The results of the present study identify a novel regulatory mechanism of ERK3 that operates in a cell-cycle-dependent manner.

scholarly journals Dual Mechanism of Action of 5-Nitro-1,10-Phenanthroline against Mycobacterium tuberculosis

2017 ◽  
Vol 61 (11) ◽  
Author(s):  
Saqib Kidwai ◽  
Chan-Yong Park ◽  
Shradha Mawatwal ◽  
Prabhakar Tiwari ◽  
Myung Geun Jung ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Mechanism Of Action ◽  
Chemotherapeutic Agents ◽  
Intracellular Bacteria ◽  
Dependent Manner ◽  
Content Type ◽  
Structure Activity ◽  
Dual Mechanism

ABSTRACT New chemotherapeutic agents with novel mechanisms of action are urgently required to combat the challenge imposed by the emergence of drug-resistant mycobacteria. In this study, a phenotypic whole-cell screen identified 5-nitro-1,10-phenanthroline (5NP) as a lead compound. 5NP-resistant isolates harbored mutations that were mapped to fbiB and were also resistant to the bicyclic nitroimidazole PA-824. Mechanistic studies confirmed that 5NP is activated in an F420-dependent manner, resulting in the formation of 1,10-phenanthroline and 1,10-phenanthrolin-5-amine as major metabolites in bacteria. Interestingly, 5NP also killed naturally resistant intracellular bacteria by inducing autophagy in macrophages. Structure-activity relationship studies revealed the essentiality of the nitro group for in vitro activity, and an analog, 3-methyl-6-nitro-1,10-phenanthroline, that had improved in vitro activity and in vivo efficacy in mice compared with that of 5NP was designed. These findings demonstrate that, in addition to a direct mechanism of action against Mycobacterium tuberculosis, 5NP also modulates the host machinery to kill intracellular pathogens.

scholarly journals Suppression of CD13 Enhances the Cytotoxic Effect of Chemotherapeutic Drugs in Hepatocellular Carcinoma Cells

2021 ◽  
Vol 12 ◽  
Author(s):  
Shengping Ji ◽  
Yuqian Ma ◽  
Xiaoyan Xing ◽  
Binbin Ge ◽  
Yutian Li ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Chemotherapy Resistance ◽  
Chemotherapeutic Agents ◽  
Ros Generation ◽  
Cancer Resistance ◽  
Ros Scavenging ◽  
Chemotherapy Agent ◽  
Hepatocarcinoma Cells

Multidrug resistance (MDR) of hepatocellular carcinoma (HCC) is a serious problem that directly hinders the effect of chemotherapeutics. In this study, we mainly explore the molecular mechanism of ROS-induced CD13 expression using hepatocarcinoma cells as the research object. We show that the drug of fluorouracil (5FU), epirubicin (EPI) and gemcitabine (GEM) can induce ROS generation, activate Ets2 and promote CD13 expression. Meanwhile, CD13 can activate NRF1 and up-regulate ROS scavenging genes transcription, such as SOD1, GPX1, GPX2 and GPX3, leading to down-regulation of intracellular ROS level and reducing the sensitivity of cells to chemotherapy agent. We also detected the anti-tumor effect of the combination therapy, CD13 inhibitor ubenimex and a variety of conventional anti-cancer drugs, such as 5FU, EPI, GEM, pemetrexed (Pem) and paclitaxel (PTX) were employed in combination. Ubenimex enhances the sensitivity of different chemotherapeutic agents and cooperates with chemotherapeutic agents to suppress tumor growth in vitro and in vivo. In general, overexpression of CD13 can lead to chemotherapy resistance, and CD13 inhibitor can reverse this effect. Combination of chemotherapy agent and ubenimex will become a potential treatment strategy for liver cancer resistance.

Sign in / Sign up

Export Citation Format

Share Document