scholarly journals Histone methyltransferase EHMT2 degradation by propionate derived from Bacteroides thetaiotaomicron induced colon cancer apoptosis via epigenetic regulation of TNFAIP1

2020 ◽  
Author(s):  
Tae Young Ryu ◽  
Kwangho Kim ◽  
Tae-Su Han ◽  
Mi-Ok Lee ◽  
Jinkwon Lee ◽  
...  

Abstract BackgroundBacteroides thetaiotaomicron (BT) is the second most commonly isolated bacterium in the human microbiome after B. fragilis and is involved in the hydrolysis of glycosidic bonds in dietary carbohydrates. Although the human microbiome has recently been shown to affect colorectal cancer (CRC) treatment, the mode of action (MOA) between the microbiome and CRC is still unclear.MethodsTo assess the colon cancer apoptosis, we performed western blot, qRT-PCR and FACS analysis using BT supernatant (Sup), sodium propionate (SP), and EHMT2 specific siRNA. Using RNA-seq analysis and ChIP-seq analysis, we identified HECTD2 (E3 ligase) and TNFAIP1 (EHMT2 target) genes. The antitumor activity of EHMT2 was determined by an in vivo xenograft model.ResultsWe selected propionate derived from BT and showed that it suppressed CRC growth by promoting proteasomal degradation of EHMT2 through HECTD2 upregulation. Moreover, downregulation of EHMT2 reduced the level of H3K9me2 on the promoter region of TNFAIP1, and subsequently, upregulation of TNFAIP1 induced apoptosis of CRC cells. Finally, we performed an in vivo study using BIX01294 to inactivate EHMT2 and observed a reduction in the tumor size of the CRC xenograft models.ConclusionsWe suggest anticancer effects of BT and EHMT2 as therapeutic targets for colon cancer treatment, and we will provide the possibility for synergistic effects of an EHMT2 inhibitor and BT in CRC treatment.*Authors share co-first authorship

2021 ◽  
Author(s):  
Ying Zhang ◽  
Qiuzi Liu ◽  
Wei Wei ◽  
Guoan Zhang ◽  
Siyuan Yan ◽  
...  

Abstract Background Bortezomib (BZM), alone or in combination with other chemotherapies, has displayed strong anticancer effects in several cancers. The efficacy of the combination of BZM and mitoxantrone (MTX) in treating prostate cancer remains unknown.Methods Anticancer effects of combination of BZM and MTX were determined by apoptosis and proliferation assay in vivo and in vitro. Expression of β-catenin and its target genes were characterized by western blot and Real-time PCR.Results BZM significantly enhanced MTX-induced antiproliferation in vivo and in vitro. Mice administered a combination of BZM and MTX displayed attenuated tumor growth and prolonged survival. BZM significantly attenuated MTX-induced apoptosis. Moreover, the combination of BZM and MTX contributed to inhibition of the Wnt/β-catenin signaling pathway compared to monotherapy.Conclusions This study demonstrates that BZM enhances MTX-induced anti-tumor effects by inhibiting the Wnt/β-catenin signaling pathway in prostate cancer cells.


BMC Cancer ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Ying Zhang ◽  
Qiuzi Liu ◽  
Wei Wei ◽  
Guoan Zhang ◽  
Siyuan Yan ◽  
...  

Abstract Background Bortezomib (BZM), alone or in combination with other chemotherapies, has displayed strong anticancer effects in several cancers. The efficacy of the combination of BZM and mitoxantrone (MTX) in treating prostate cancer remains unknown. Methods Anticancer effects of combination of BZM and MTX were determined by apoptosis and proliferation assay in vivo and in vitro. Expression of β-Catenin and its target genes were characterized by western blot and Real-time PCR. Results BZM significantly enhanced MTX-induced antiproliferation in vivo and in vitro. Mice administered a combination of BZM and MTX displayed attenuated tumor growth and prolonged survival. BZM significantly attenuated MTX-induced apoptosis. Moreover, the combination of BZM and MTX contributed to inhibition of the Wnt/β-Catenin signaling pathway compared to monotherapy. Conclusions This study demonstrates that BZM enhances MTX-induced anti-tumor effects by inhibiting the Wnt/β-Catenin signaling pathway in prostate cancer cells.


2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Jing Liu ◽  
Shuaiyu Long ◽  
Huanan Wang ◽  
Nannan Liu ◽  
Chuchu Zhang ◽  
...  

Abstract Background Autophagy is an evolutionarily conserved process through which cells degrade and recycle cytoplasm. The relation among autophagy, apoptosis and tumor is highly controversial until now and the molecular mechanism is poorly understood. Methods Cell viability and apoptosis were detected by CCK8, crystal violet staining, Hoechst333342 staining and flow cytometry. The expression of AMPK and ULK1 was analyzed by western blotting. Colon cancer growth suppression by NVP-BEZ235 or CQ in vivo was studied in a tumor xenograft mouse model. Results Our previous study revealed that NVP-BEZ235 suppressed colorectal cancer growth via inducing apoptosis, however later, we found it also initiated autophagy simultaneously. In this present study, our results show that NVP-BEZ235 induced autophagy through AMPK/ULK1 pathway in colon cancer cells. Blocking autophagy by knocking down AMPK or ULK1 inhibited cell proliferation and further promoted NVP-BEZ235 induced apoptosis. Meantime, the autophagy inhibitor chloroquine (CQ) shows obvious effect on inhibiting cell proliferation but not on inducing apoptosis, while it significantly increased NVP-BEZ235 induced apoptosis. Furthermore, the combinational therapy of NVP-BEZ235 and CQ shows synergistic antitumor effects in colon cancer in vivo. Conclusion NVP-BEZ235 induced AMPK/ULK1-dependent autophagy. Targeting this autophagy suppressed colon cancer growth through further promoting apoptosis, which is a potential therapeutic option for clinical patients.


Blood ◽  
2020 ◽  
Author(s):  
Yun Tan ◽  
Xiaoling Wang ◽  
Huan Song ◽  
Yi Zhang ◽  
Rongsheng Zhang ◽  
...  

Transcriptional deregulation initiated by oncogenic fusion proteins plays a vital role in leukemia. The prevailing view is that the oncogenic fusion protein PML/RARα, generated by the chromosome translocation t(15;17), functions as a transcriptional repressor in acute promyelocytic leukemia (APL). Here we provide rich evidence of how PML/RARα drives oncogenesis through both repressive and activating functions, particularly the importance of the newly identified activation role for the leukemogenesis of APL. The activating function of PML/RARα is achieved by recruiting both abundant P300 and HDAC1 and by the formation of super-enhancers. All-trans retinoic acid and arsenic trioxide, two widely used drugs in APL therapy, exert synergistic effects on controlling super-enhancer-associated PML/RARα-regulated targets in APL cells. We utilize a series of in vitro and in vivo experiments to demonstrate that PML/RARα-activated target gene GFI1 is necessary for the maintenance of APL cells, and that PML/RARα, likely oligomerized, transactivates GFI1 through chromatin conformation at the super-enhancer region. Finally, we profile GFI1 targets and reveal the interplay between GFI1 and PML/RARα on chromatin in co-regulating target genes. Our study provides genomic insight into the dual role of fusion transcription factors in transcriptional deregulation to drive leukemia development, highlighting the importance of globally dissecting regulatory circuits.


2007 ◽  
Vol 292 (1) ◽  
pp. G28-G38 ◽  
Author(s):  
Yanna Cao ◽  
Lu Chen ◽  
Weili Zhang ◽  
Yan Liu ◽  
Harry T. Papaconstantinou ◽  
...  

Transforming growth factor (TGF)-β-dependent apoptosis is important in the elimination of damaged or abnormal cells from normal tissues in vivo. Previously, we have shown that TGF-β inhibits the growth of rat intestinal epithelial (RIE)-1 cells. However, RIE-1 cells are relatively resistant to TGF-β-induced apoptosis due to a low endogenous Smad3-to-Akt ratio. Overexpression of Smad3 sensitizes RIE-1 cells (RIE-1/Smad3) to TGF-β-induced apoptosis by altering the Smad3-to-Akt ratio in favor of apoptosis. In this study, we utilized a genomic approach to identify potential downstream target genes that are regulated by TGF-β/Smad3. Total RNA samples were analyzed using Affymetrix oligonucleotide microarrays. We found that TGF-β regulated 518 probe sets corresponding to its target genes. Interestingly, among the known apoptotic genes included in the microarray analyses, only caspase-3 was induced, which was confirmed by real-time RT-PCR. Furthermore, TGF-β activated caspase-3 through protein cleavage. Upstream of caspase-3, TGF-β induced mitochondrial depolarization, cytochrome c release, and cleavage of caspase-9, which suggests that the intrinsic apoptotic pathway mediates TGF-β-induced apoptosis in RIE-1/Smad3 cells.


2020 ◽  
Vol 12 ◽  
pp. 175883592093742
Author(s):  
Wen Peng ◽  
Huaqing Zhang ◽  
Shisheng Tan ◽  
Yan Li ◽  
Yang Zhou ◽  
...  

Background: Lysine-specific histone demethylase 1 (LSD1) is a potential target of cancer therapy. In the present study, we aimed to investigate the combined antitumor activity of a novel LSD1 inhibitor (ZY0511) with 5-fluorouracil (5-FU) and elucidate the underlying mechanism in colorectal cancer (CRC). Methods: We evaluated LSD1 expression in CRC tissues from patients who received 5-FU treatment. The synergistic antitumor effect of 5-FU with ZY0511 against human CRC cells was detected both in vitro and in vivo. The underlying mechanism was explored based on mRNA sequencing (mRNA-seq) technology. Results: Overexpression of LSD1 was observed in human CRC tissues, and correlated with CRC development and 5-FU resistance. ZY0511, a novel LSD1 inhibitor, effectively inhibited CRC cells proliferation, both in vitro and in vivo. Notably, the combination of ZY0511 and 5-FU synergistically reduced CRC cells viability and migration in vitro. It also suppressed Wnt/β-catenin signaling and DNA synthesis pathways, which finally induced apoptosis of CRC cells. In addition, the combination of ZY0511 with 5-FU significantly reduced CRC xenograft tumor growth, along with lung and liver metastases in vivo. Conclusions: Our findings identify LSD1 as a potential marker for 5-FU resistance in CRC. ZY0511 is a promising candidate for CRC therapy as it potentiates 5-FU anticancer effects, thereby providing a new combinatorial strategy for treating CRC.


Blood ◽  
2008 ◽  
Vol 112 (5) ◽  
pp. 1981-1992 ◽  
Author(s):  
Winnie F. Tam ◽  
Ting-Lei Gu ◽  
Jing Chen ◽  
Benjamin H. Lee ◽  
Lars Bullinger ◽  
...  

Abstract Oncogenic tyrosine kinases, such as BCR-ABL, TEL-ABL, TEL-PDGFβR, and FLT3-ITD, play a major role in the development of hematopoietic malignancy. They activate many of the same signal transduction pathways. To identify the critical target genes required for transformation in hematopoietic cells, we used a comparative gene expression strategy in which selective small molecules were applied to 32Dcl3 cells that had been transformed to factor-independent growth by these respective oncogenic alleles. We identified inhibitor of DNA binding 1 (Id1), a gene involved in development, cell cycle, and tumorigenesis, as a common target of these oncogenic kinases. These findings were prospectively confirmed in cell lines and primary bone marrow cells engineered to express the respective tyrosine kinase alleles and were also confirmed in vivo in murine models of disease. Moreover, human AML cell lines Molm-14 and K562, which express the FLT3-ITD and BCR-ABL tyrosine kinases, respectively, showed high levels of Id1 expression. Antisense and siRNA based knockdown of Id1-inhibited growth of these cells associated with increased p27Kip1 expression and increased sensitivity to Trail-induced apoptosis. These findings indicate that Id1 is an important target of constitutively activated tyrosine kinases and may be a therapeutic target for leukemias associated with oncogenic tyrosine kinases.


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