Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 30
Filter
Add more filters










Publication year range
1.
J Med Chem ; 67(10): 7921-7934, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38713486

ABSTRACT

CARM1, belonging to the protein arginine methyltransferase (PRMT) family, is intricately associated with the progression of cancer and is viewed as a promising target for both cancer diagnosis and therapy. However, the number of specific and potent CARM1 inhibitors is limited. We herein discovered a CARM1 inhibitor, iCARM1, that showed better specificity and activity toward CARM1 compared to the known CARM1 inhibitors, EZM2302 and TP-064. Similar to CARM1 knockdown, iCARM1 suppressed the expression of oncogenic estrogen/ERα-target genes, whereas activated type I interferon (IFN) and IFN-induced genes (ISGs) in breast cancer cells. Consequently, iCARM1 potently suppressed breast cancer cell growth both in vitro and in vivo. The combination of iCARM1 with either endocrine therapy drugs or etoposide demonstrated synergistic effects in inhibiting the growth of breast tumors. In summary, targeting CARM1 by iCARM1 effectively suppresses breast tumor growth, offering a promising therapeutic approach for managing breast cancers in clinical settings.


Subject(s)
Breast Neoplasms , Cell Proliferation , Protein-Arginine N-Methyltransferases , Humans , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Protein-Arginine N-Methyltransferases/antagonists & inhibitors , Protein-Arginine N-Methyltransferases/metabolism , Female , Animals , Mice , Cell Proliferation/drug effects , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/therapeutic use , Cell Line, Tumor , Mice, Nude , Mice, Inbred BALB C , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/therapeutic use
2.
Nucleic Acids Res ; 52(12): 6811-6829, 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38676947

ABSTRACT

Protein arginine methyltransferase CARM1 has been shown to methylate a large number of non-histone proteins, and play important roles in gene transcriptional activation, cell cycle progress, and tumorigenesis. However, the critical substrates through which CARM1 exerts its functions remain to be fully characterized. Here, we reported that CARM1 directly interacts with the GATAD2A/2B subunit in the nucleosome remodeling and deacetylase (NuRD) complex, expanding the activities of NuRD to include protein arginine methylation. CARM1 and NuRD bind and activate a large cohort of genes with implications in cell cycle control to facilitate the G1 to S phase transition. This gene activation process requires CARM1 to hypermethylate GATAD2A/2B at a cluster of arginines, which is critical for the recruitment of the NuRD complex. The clinical significance of this gene activation mechanism is underscored by the high expression of CARM1 and NuRD in breast cancers, and the fact that knockdown CARM1 and NuRD inhibits cancer cell growth in vitro and tumorigenesis in vivo. Targeting CARM1-mediated GATAD2A/2B methylation with CARM1 specific inhibitors potently inhibit breast cancer cell growth in vitro and tumorigenesis in vivo. These findings reveal a gene activation program that requires arginine methylation established by CARM1 on a key chromatin remodeler, and targeting such methylation might represent a promising therapeutic avenue in the clinic.


Subject(s)
Breast Neoplasms , Chromatin Assembly and Disassembly , Gene Expression Regulation, Neoplastic , Mi-2 Nucleosome Remodeling and Deacetylase Complex , Protein-Arginine N-Methyltransferases , Mi-2 Nucleosome Remodeling and Deacetylase Complex/metabolism , Mi-2 Nucleosome Remodeling and Deacetylase Complex/genetics , Protein-Arginine N-Methyltransferases/genetics , Protein-Arginine N-Methyltransferases/metabolism , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Breast Neoplasms/metabolism , Humans , Female , Animals , Cell Line, Tumor , Cell Cycle/genetics , Mice , Methylation , Arginine/metabolism , Carcinogenesis/genetics , Transcriptional Activation
3.
Cell Mol Life Sci ; 81(1): 121, 2024 Mar 08.
Article in English | MEDLINE | ID: mdl-38457049

ABSTRACT

Esophageal squamous cell carcinoma (ESCC) is one of the most prevalent gastrointestinal malignancies with high mortality worldwide. Emerging evidence indicates that long noncoding RNAs (lncRNAs) are involved in human cancers, including ESCC. However, the detailed mechanisms of lncRNAs in the regulation of ESCC progression remain incompletely understood. LUESCC was upregulated in ESCC tissues compared with adjacent normal tissues, which was associated with gender, deep invasion, lymph node metastasis, and poor prognosis of ESCC patients. LUESCC was mainly localized in the cytoplasm of ESCC cells. Knockdown of LUESCC inhibited cell proliferation, colony formation, migration, and invasion in vitro and suppressed tumor growth in vivo. Mechanistic investigation indicated that LUESCC functions as a ceRNA by sponging miR-6785-5p to enhance NRSN2 expression, which is critical for the malignant behaviors of ESCC. Furthermore, ASO targeting LUESCC substantially suppressed ESCC both in vitro and in vivo. Collectively, these data demonstrate that LUESCC may exerts its oncogenic role by sponging miR-6785-5p to promote NRSN2 expression in ESCC, providing a potential diagnostic marker and therapeutic target for ESCC patients.


Subject(s)
Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , MicroRNAs , RNA, Long Noncoding , Humans , Cell Line, Tumor , Disease Progression , Esophageal Neoplasms/metabolism , Esophageal Squamous Cell Carcinoma/genetics , Gene Expression Regulation, Neoplastic , MicroRNAs/genetics , MicroRNAs/metabolism , Neoplasm Invasiveness/genetics , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism
4.
Proc Natl Acad Sci U S A ; 121(2): e2219352120, 2024 Jan 09.
Article in English | MEDLINE | ID: mdl-38165927

ABSTRACT

High levels of mitochondrial reactive oxygen species (mROS) are linked to cancer development, which is tightly controlled by the electron transport chain (ETC). However, the epigenetic mechanisms governing ETC gene transcription to drive mROS production and cancer cell growth remain to be fully characterized. Here, we report that protein demethylase PHF8 is overexpressed in many types of cancers, including colon and lung cancer, and is negatively correlated with ETC gene expression. While it is well known to demethylate histones to activate transcription, PHF8 demethylates transcription factor YY1, functioning as a co-repressor for a large set of nuclear-coded ETC genes to drive mROS production and cancer development. In addition to genetically ablating PHF8, pharmacologically targeting PHF8 with a specific chemical inhibitor, iPHF8, is potent in regulating YY1 methylation, ETC gene transcription, mROS production, and cell growth in colon and lung cancer cells. iPHF8 exhibits potency and safety in suppressing tumor growth in cell-line- and patient-derived xenografts in vivo. Our data uncover a key epigenetic mechanism underlying ETC gene transcriptional regulation, demonstrating that targeting the PHF8/YY1 axis has great potential to treat cancers.


Subject(s)
Lung Neoplasms , Transcription Factors , Humans , Transcription Factors/metabolism , Reactive Oxygen Species/metabolism , Histone Demethylases/metabolism , Histones/metabolism , Cell Transformation, Neoplastic , Lung Neoplasms/genetics , YY1 Transcription Factor/genetics , YY1 Transcription Factor/metabolism
5.
Proc Natl Acad Sci U S A ; 120(41): e2304534120, 2023 10 10.
Article in English | MEDLINE | ID: mdl-37782793

ABSTRACT

Aberrant transcripts expression of the m6A methyltransferase complex (MTC) is widely found across human cancers, suggesting a dysregulated signaling cascade which integrates m6A epitranscriptome to drive tumorigenesis. However, the responsible transcriptional machinery directing the expression of distinct MTC subunits remains unclear. Here, we identified an unappreciated interplay between the histone acetyl-lysine reader BRD4 and the m6A writer complex across human cancers. BRD4 directly stimulates transcripts expression of seven MTC subunits, allowing the maintenance of the nuclear writer complex integrity. Upon BET inhibition, this BRD4-MTC signaling cascade accounts for global m6A reduction and the subsequent dynamic alteration of BRD4-dependent transcriptome, resulting in impaired DNA damage response that involves activation of homologous recombination (HR) repair and repression of apoptosis. We further demonstrated that the combined synergy upon BET/PARP inhibition largely relies on disrupted m6A modification of HR and apoptotic genes, counteracting PARP inhibitor (PARPi) resistance in patient-derived xenograft models. Our study revealed a widespread active cross-talk between BRD4-dependent epigenetic and MTC-mediated epitranscriptomic networks, which provides a unique therapeutic vulnerability that can be leveraged in combined DNA repair-targeted therapy.


Subject(s)
Antineoplastic Agents , Bromodomain Containing Proteins , Nuclear Proteins , Humans , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Cell Line, Tumor , DNA Repair , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology , Transcription Factors/genetics , Transcription Factors/metabolism , Epigenesis, Genetic , Bromodomain Containing Proteins/genetics , Bromodomain Containing Proteins/metabolism , Animals
6.
Sci Adv ; 9(35): eadg7053, 2023 09.
Article in English | MEDLINE | ID: mdl-37656786

ABSTRACT

Pattern recognition receptor-mediated innate immunity is critical for host defense against viruses. A growing number of coding and noncoding genes are found to encode microproteins. However, the landscape and functions of microproteins in responsive to virus infection remain uncharacterized. Here, we systematically identified microproteins that are responsive to vesicular stomatitis virus infection. A conserved and endoplasmic reticulum-localized membrane microprotein, MAVI1 (microprotein in antiviral immunity 1), was found to interact with mitochondrion-localized MAVS protein and inhibit MAVS aggregation and type I interferon signaling activation. The importance of MAVI1 was highlighted that viral infection was attenuated and survival rate was increased in Mavi1-knockout mice. A peptide inhibitor targeting the interaction between MAVI1 and MAVS activated the type I interferon signaling to defend viral infection. Our findings uncovered that microproteins play critical roles in regulating antiviral innate immune responses, and targeting microproteins might represent a therapeutic avenue for treating viral infection.


Subject(s)
Immunity, Innate , Interferon Type I , Animals , Mice , Antiviral Agents , Endoplasmic Reticulum , Mice, Knockout , Mitochondria , Micropeptides
7.
Adv Sci (Weinh) ; 10(25): e2206663, 2023 09.
Article in English | MEDLINE | ID: mdl-37404090

ABSTRACT

Endocrine therapy is the frontline treatment for estrogen receptor (ER) positive breast cancer patients. However, the primary and acquired resistance to endocrine therapy drugs remain as a major challenge in the clinic. Here, this work identifies an estrogen-induced lncRNA, LINC02568, which is highly expressed in ER-positive breast cancer and functional important in cell growth in vitro and tumorigenesis in vivo as well as endocrine therapy drug resistance. Mechanically, this work demonstrates that LINC02568 regulates estrogen/ERα-induced gene transcriptional activation in trans by stabilizing ESR1 mRNA through sponging miR-1233-5p in the cytoplasm. Meanwhile, LINC02568 contributes to tumor-specific pH homeostasis by regulating carbonic anhydrase CA12 in cis in the nucleus. The dual functions of LINC02568 together contribute to breast cancer cell growth and tumorigenesis as well as endocrine therapy drug resistance. Antisense oligonucleotides (ASO) targeting LINC02568 significantly inhibits ER-positive breast cancer cell growth in vitro and tumorigenesis in vivo. Furthermore, combination treatment with ASO targeting LINC02568 and endocrine therapy drugs or CA12 inhibitor U-104 exhibits synergistic effects on tumor growth. Taken together, the findings reveal the dual mechanisms of LINC02568 in regulating ERα signaling and pH homeostasis in ER-positive breast cancer, and indicated that targeting LINC02568 might represent a potential therapeutic avenue in the clinic.


Subject(s)
Breast Neoplasms , RNA, Long Noncoding , Humans , Female , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Estrogen Receptor alpha/genetics , Receptors, Estrogen/therapeutic use , RNA, Long Noncoding/genetics , Cell Line, Tumor , Estrogens/therapeutic use , Drug Resistance, Neoplasm/genetics , Carcinogenesis
8.
EMBO J ; 42(10): e112408, 2023 05 15.
Article in English | MEDLINE | ID: mdl-37009655

ABSTRACT

The molecular mechanisms underlying estrogen receptor (ER)-positive breast carcinogenesis and endocrine therapy resistance remain incompletely understood. Here, we report that circPVT1, a circular RNA generated from the lncRNA PVT1, is highly expressed in ERα-positive breast cancer cell lines and tumor samples and is functionally important in promoting ERα-positive breast tumorigenesis and endocrine therapy resistance. CircPVT1 acts as a competing endogenous RNA (ceRNA) to sponge miR-181a-2-3p, promoting the expression of ESR1 and downstream ERα-target genes and breast cancer cell growth. Furthermore, circPVT1 directly interacts with MAVS protein to disrupt the RIGI-MAVS complex formation, inhibiting type I interferon (IFN) signaling pathway and anti-tumor immunity. Anti-sense oligonucleotide (ASO)-targeting circPVT1 inhibits ERα-positive breast cancer cell and tumor growth, re-sensitizing tamoxifen-resistant ERα-positive breast cancer cells to tamoxifen treatment. Taken together, our data demonstrated that circPVT1 can work through both ceRNA and protein scaffolding mechanisms to promote cancer. Thus, circPVT1 may serve as a diagnostic biomarker and therapeutic target for ERα-positive breast cancer in the clinic.


Subject(s)
Breast Neoplasms , RNA, Circular , Female , Humans , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Carcinogenesis/genetics , Cell Line, Tumor , Cell Proliferation , Cell Transformation, Neoplastic/genetics , Drug Resistance, Neoplasm/genetics , Estrogen Receptor alpha/genetics , Estrogen Receptor alpha/metabolism , Gene Expression Regulation, Neoplastic , Tamoxifen/pharmacology , Tamoxifen/therapeutic use , RNA, Circular/genetics , RNA, Circular/metabolism
9.
Dev Cell ; 58(9): 760-778.e6, 2023 05 08.
Article in English | MEDLINE | ID: mdl-37054705

ABSTRACT

The STING-mediated type I interferon (IFN) signaling pathway has been shown to play critical roles in antitumor immunity. Here, we demonstrate that an endoplasmic reticulum (ER)-localized JmjC domain-containing protein, JMJD8, inhibits STING-induced type I IFN responses to promote immune evasion and breast tumorigenesis. Mechanistically, JMJD8 competes with TBK1 for binding with STING, blocking STING-TBK1 complex formation and restricting type I IFN and IFN-stimulated gene (ISG) expression as well as immune cell infiltration. JMJD8 knockdown improves the efficacy of chemotherapy and immune checkpoint therapy in treating both human and mouse breast cancer cell-derived implanted tumors. The clinical relevance is highlighted in that JMJD8 is highly expressed in human breast tumor samples, and its expression is inversely correlated with that of type I IFN and ISGs as well as immune cell infiltration. Overall, our study found that JMJD8 regulates type I IFN responses, and targeting JMJD8 triggers antitumor immunity.


Subject(s)
Breast Neoplasms , Immune Evasion , Animals , Female , Humans , Mice , Endoplasmic Reticulum/metabolism , Immunity, Innate , Membrane Proteins/genetics , Membrane Proteins/metabolism , Signal Transduction/genetics
10.
Nat Commun ; 13(1): 6350, 2022 10 26.
Article in English | MEDLINE | ID: mdl-36289222

ABSTRACT

The methyltransferase like 3 (METTL3) has been generally recognized as a nuclear protein bearing oncogenic properties. We find predominantly cytoplasmic METTL3 expression inversely correlates with node metastasis in human cancers. It remains unclear if nuclear METTL3 is functionally distinct from cytosolic METTL3 in driving tumorigenesis and, if any, how tumor cells sense oncogenic insults to coordinate METTL3 functions within these intracellular compartments. Here, we report an acetylation-dependent regulation of METTL3 localization that impacts on metastatic dissemination. We identify an IL-6-dependent positive feedback axis to facilitate nuclear METTL3 functions, eliciting breast cancer metastasis. IL-6, whose mRNA transcript is subjected to METTL3-mediated m6A modification, promotes METTL3 deacetylation and nuclear translocation, thereby inducing global m6A abundance. This deacetylation-mediated nuclear shift of METTL3 can be counterbalanced by SIRT1 inhibition, a process that is further enforced by aspirin treatment, leading to ablated lung metastasis via impaired m6A methylation. Intriguingly, acetylation-mimetic METTL3 mutant reconstitution results in enhanced translation and compromised metastatic potential. Our study identifies an acetylation-dependent regulatory mechanism determining the subcellular localization of METTL3, which may provide mechanistic clues for developing therapeutic strategies to combat breast cancer metastasis.


Subject(s)
Breast Neoplasms , Methyltransferases , Humans , Female , Methyltransferases/metabolism , Acetylation , Sirtuin 1/metabolism , Interleukin-6/metabolism , RNA, Messenger/metabolism , Carcinogenesis , Breast Neoplasms/genetics , Nuclear Proteins/metabolism , Aspirin
11.
Mol Cancer ; 21(1): 69, 2022 03 07.
Article in English | MEDLINE | ID: mdl-35255921

ABSTRACT

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is a common invasive malignancy worldwide with poor clinical outcomes. Increasing amount of long non-coding RNAs (lncRNAs) have been reported to be involved in cancer development. However, lncRNAs that are functional in ESCC and the underlying molecular mechanisms remain largely unknown. METHODS: Transcriptomic analysis was performed to identify dysregulated lncRNAs in ESCC tissue samples. The high expression of LINC00680 in ESCC was validated by RT-qPCR, and the oncogenic functions of LINC00680 was investigated by cell proliferation, colony formation, migration and invasion assays in ESCC cells in vitro and xenografts derived from ESCC cells in mice. RNA-seq, competitive endogenous RNA (ceRNA) network analysis, and luciferase reporter assays were carried out to identify LINC00680 target genes and the microRNAs (miRNAs) bound to LINC00680. Antisense oligonucleotides (ASOs) were used for in vivo treatment. RESULTS: Transcriptome profiling revealed that a large number of lncRNAs was dysregulated in ESCC tissues. Notably, LINC00680 was highly expressed, and upregulation of LINC00680 was associated with large tumor size, advanced tumor stage, and poor prognosis. Functionally, knockdown of LINC00680 restrained ESCC cell proliferation, colony formation, migration, and invasion in vitro and inhibited tumor growth in vivo. Mechanistically, LINC00680 was found to act as a ceRNA by sponging miR-423-5p to regulate PAK6 (p21-activated kinase 6) expression in ESCC cells. The cell viability and motility inhibition induced by LINC00680 knockdown was significantly reversed upon PAK6 restoration and miR-423-5p inhibition. Furthermore, ASO targeting LINC00680 substantially suppressed ESCC both in vitro and in vivo. CONCLUSIONS: An oncogenic lncRNA, LINC00680, was identified in ESCC, which functions as a ceRNA by sponging miR-423-5p to promote PAK6 expression and ESCC. LINC00680/miR-423-5p/PAK6 axis may serve as promising diagnostic and prognostic biomarkers and therapeutic targets for ESCC.


Subject(s)
Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , MicroRNAs , RNA, Long Noncoding , p21-Activated Kinases , Animals , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Disease Progression , Esophageal Neoplasms/pathology , Esophageal Squamous Cell Carcinoma/pathology , Gene Expression Regulation, Neoplastic , Humans , Mice , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , p21-Activated Kinases/genetics , p21-Activated Kinases/metabolism
12.
Mol Ther ; 30(2): 688-702, 2022 02 02.
Article in English | MEDLINE | ID: mdl-34371180

ABSTRACT

Long non-coding RNAs (lncRNAs) play critical roles in tumorigenesis and progression of colorectal cancer (CRC). However, functions of most lncRNAs in CRC and their molecular mechanisms remain uncharacterized. Here we found that lncRNA ITGB8-AS1 was highly expressed in CRC. Knockdown of ITGB8-AS1 suppressed cell proliferation, colony formation, and tumor growth in CRC, suggesting oncogenic roles of ITGB8-AS1. Transcriptomic analysis followed by KEGG analysis revealed that focal adhesion signaling was the most significantly enriched pathway for genes positively regulated by ITGB8-AS1. Consistently, knockdown of ITGB8-AS1 attenuated the phosphorylation of SRC, ERK, and p38 MAPK. Mechanistically, ITGB8-AS1 could sponge miR-33b-5p and let-7c-5p/let-7d-5p to regulate the expression of integrin family genes ITGA3 and ITGB3, respectively, in the cytosol of cells. Targeting ITGB8-AS1 using antisense oligonucleotide (ASO) markedly reduced cell proliferation and tumor growth in CRC, indicating the therapeutic potential of ITGB8-AS1 in CRC. Furthermore, ITGB8-AS1 was easily detected in plasma of CRC patients, which was positively correlated with differentiation and TNM stage, as well as plasma levels of ITGA3 and ITGB3. In conclusion, ITGB8-AS1 functions as a competing endogenous RNA (ceRNA) to regulate cell proliferation and tumor growth of CRC via regulating focal adhesion signaling. Targeting ITGB8-AS1 is effective in suppressing CRC cell growth and tumor growth. Elevated plasma levels of ITGB8-AS1 were detected in advanced-stage CRC. Thus, ITGB8-AS1 could serve as a potential therapeutic target and circulating biomarker in CRC.


Subject(s)
Colorectal Neoplasms , MicroRNAs , RNA, Long Noncoding , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Focal Adhesions/genetics , Focal Adhesions/metabolism , Focal Adhesions/pathology , Gene Expression Regulation, Neoplastic , Humans , Integrin beta Chains , Integrins/genetics , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism
13.
Front Genet ; 12: 752495, 2021.
Article in English | MEDLINE | ID: mdl-34707642

ABSTRACT

Spermatocyte meiosis is the cornerstone of mammalian production. Thousands of long noncoding RNAs (lncRNAs) have been reported to be functional in various cellular processes, but the function of lncRNAs in meiosis remains largely unknown. Here, we profiled lncRNAs in spermatocytes at stage I of meiosis and identified a testis-specific lncRNA, Rbakdn, as a vital regulator of meiosis. Rbakdn is dynamically expressed during meiosis I, and Rbakdn knockdown inhibits meiosis in vitro. Furthermore, Rbakdn knockdown in testes in mice by intratesticular injection disturbs meiosis, reduces testicular volume, and increases apoptosis of spermatocytes, resulting in vacuolation of the seminiferous tubules. Rbakdn can bind to Ptbp2, an RNA-binding protein that is important in the regulation of the alternative splicing of many genes in spermatogenesis. Rbakdn knockdown leads to a decrease in Ptbp2 through the ubiquitination degradation pathway, indicating that Rbakdn maintains the stability of Ptbp2. In conclusion, our study identified an lncRNA, Rbakdn, with a crucial role in meiosis.

14.
Adv Sci (Weinh) ; 8(15): e2004504, 2021 08.
Article in English | MEDLINE | ID: mdl-34050636

ABSTRACT

Genomic amplification of OTUD7B is frequently found across human cancers. But its role in tumorigenesis is poorly understood. Lysine-specific demethylase 1 (LSD1) is known to execute epigenetic regulation by forming corepressor complex with CoREST/histone deacetylases (HDACs). However, the molecular mechanisms by which cells maintain LSD1/CoREST complex integrity are unknown. Here, it is reported that LSD1 protein undergoes K63-linked polyubiquitination. OTUD7B is responsible for LSD1 deubiquitination at K226/277 residues, resulting in dynamic control of LSD1 binding partner specificity and cellular homeostasis. OTUD7B deficiency increases K63-linked ubiquitination of LSD1, which disrupts LSD1/CoREST complex formation and targets LSD1 for p62-mediated proteolysis. Consequently, OTUD7B deficiency impairs genome-wide LSD1 occupancy and enhances the methylation of H3K4/H3K9, therefore profoundly impacting global gene expression and abrogating breast cancer metastasis. Moreover, physiological fluctuation of OTUD7B modulates cell cycle-dependent LSD1 oscillation, ensuring the G1/S transition. Both OTUD7B and LSD1 proteins are overpresented in high-grade or metastatic human breast cancer, while dysregulation of either protein is associated with poor survival and metastasis. Thus, OTUD7B plays a unique partner-switching role in maintaining the integrity of LSD1/CoREST corepressor complex, LSD1 turnover, and breast cancer metastasis.


Subject(s)
Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Endopeptidases/metabolism , Histone Demethylases/metabolism , Protein Processing, Post-Translational/physiology , Ubiquitination/physiology , Animals , Breast Neoplasms/genetics , Disease Models, Animal , Endopeptidases/genetics , Female , Histone Demethylases/genetics , Homeostasis/genetics , Homeostasis/physiology , Mice , Mice, Nude , Neoplasm Metastasis , Protein Binding , Protein Processing, Post-Translational/genetics , Ubiquitination/genetics
15.
Mol Ther ; 29(10): 3011-3026, 2021 10 06.
Article in English | MEDLINE | ID: mdl-34058385

ABSTRACT

Glioblastoma (GBM) is the deadliest brain malignancy without effective treatments. Here, we reported that epidermal growth factor receptor-targeted chimeric antigen receptor T cells (EGFR CAR-T) were effective in suppressing the growth of GBM cells in vitro and xenografts derived from GBM cell lines and patients in mice. However, mice soon acquired resistance to EGFR CAR-T cell treatment, limiting its potential use in the clinic. To find ways to improve the efficacy of EGFR CAR-T cells, we performed genomics and transcriptomics analysis for GBM cells incubated with EGFR CAR-T cells and found that a large cohort of genes, including immunosuppressive genes, as well as enhancers in vicinity are activated. BRD4, an epigenetic modulator functioning on both promoters and enhancers, was required for the activation of these immunosuppressive genes. Accordingly, inhibition of BRD4 by JQ1 blocked the activation of these immunosuppressive genes. Combination therapy with EGFR CAR-T cells and JQ1 suppressed the growth and metastasis of GBM cells and prolonged survival in mice. We demonstrated that transcriptional modulation by targeting epigenetic regulators could improve the efficacy of immunotherapy including CAR-T, providing a therapeutic avenue for treating GBM in the clinic.


Subject(s)
Azepines/administration & dosage , Brain Neoplasms/therapy , Cell Cycle Proteins/metabolism , ErbB Receptors/immunology , Glioblastoma/therapy , Immunotherapy, Adoptive/methods , Receptors, Chimeric Antigen/metabolism , Transcription Factors/metabolism , Triazoles/administration & dosage , Animals , Azepines/pharmacology , Brain Neoplasms/genetics , Brain Neoplasms/metabolism , Cell Cycle Proteins/antagonists & inhibitors , Cell Line, Tumor , Cell Movement/drug effects , Cell Proliferation/drug effects , Cell Survival/drug effects , Combined Modality Therapy , Epigenesis, Genetic/drug effects , Female , Gene Expression Profiling , Gene Expression Regulation, Neoplastic/drug effects , Glioblastoma/genetics , Glioblastoma/metabolism , Humans , Mice , Neoplasm Metastasis , Transcription Factors/antagonists & inhibitors , Triazoles/pharmacology , Xenograft Model Antitumor Assays
16.
Cancer Immunol Res ; 9(6): 707-722, 2021 06.
Article in English | MEDLINE | ID: mdl-33875483

ABSTRACT

EGFR-targeted chimeric antigen receptor (CAR) T cells are potent and specific in suppressing the growth of triple-negative breast cancer (TNBC) in vitro and in vivo. However, in this study, a subset of mice soon acquired resistance, which limits the potential use of EGFR CAR T cells. We aimed to find a way to overcome the observed resistance. Transcriptomic analysis results revealed that EGFR CAR T-cell treatment induced a set of immunosuppressive genes, presumably through IFNγ signaling, in EGFR CAR T-cell-resistant TNBC tumors. The EGFR CAR T-cell-induced immunosuppressive genes were associated with EGFR CAR T-cell-activated enhancers and were especially sensitive to THZ1, a CDK7 inhibitor we screened out of a panel of small molecules targeting epigenetic modulators. Accordingly, combination therapy with THZ1 and EGFR CAR T cells suppressed immune resistance, tumor growth, and metastasis in TNBC tumor models, including human MDA-MB-231 cell-derived and TNBC patient-derived xenografts, and mouse EMT6 cell-derived allografts. Taken together, we demonstrated that transcriptional modulation using epigenetic inhibitors could overcome CAR T-cell therapy-induced immune resistance, thus providing a therapeutic avenue for treating TNBC in the clinic.


Subject(s)
Antineoplastic Agents/pharmacology , ErbB Receptors/metabolism , Receptors, Antigen, T-Cell/immunology , T-Lymphocytes/immunology , Triple Negative Breast Neoplasms/metabolism , Animals , Antineoplastic Agents/metabolism , Cell Line, Tumor , Cyclin-Dependent Kinases , Drug Therapy, Combination , ErbB Receptors/immunology , Female , Humans , Mice , Mice, Inbred BALB C , Mice, Nude , Mice, SCID , Receptors, Chimeric Antigen/immunology , Triple Negative Breast Neoplasms/drug therapy , Xenograft Model Antitumor Assays , Cyclin-Dependent Kinase-Activating Kinase
17.
Theranostics ; 11(4): 1732-1752, 2021.
Article in English | MEDLINE | ID: mdl-33408778

ABSTRACT

Estrogen and estrogen receptor (ER)-regulated gene transcriptional events have been well known to be involved in ER-positive breast carcinogenesis. Meanwhile, circular RNAs (circRNAs) are emerging as a new family of functional non-coding RNAs (ncRNAs) with implications in a variety of pathological processes, such as cancer. However, the estrogen-regulated circRNA program and the function of such program remain uncharacterized. Methods: CircRNA sequencing (circRNA-seq) was performed to identify circRNAs induced by estrogen, and cell proliferation, colony formation, wound healing, transwell and tumor xenograft experiments were applied to examine the function of estrogen-induced circRNA, circPGR. RNA sequencing (RNA-seq) and ceRNA network analysis wereperformed to identify circPGR's target genes and the microRNA (miRNA) bound to circPGR. Anti-sense oligonucleotide (ASO) was used to assess circPGR's effects on ER-positive breast cancer cell growth. Results: Genome-wide circRNA profiling by circRNA sequencing (circRNA-seq) revealed that a large number of circRNAs were induced by estrogen, and further functional screening for the several circRNAs originated from PGR revealed that one of them, which we named as circPGR, was required for ER-positive breast cancer cell growth and tumorigenesis. CircPGR was found to be localized in the cytosol of cells and functioned as a competing endogenous RNA (ceRNA) to sponge miR-301a-5p to regulate the expression of multiple cell cycle genes. The clinical relevance of circPGR was underscored by its high and specific expression in ER-positive breast cancer cell lines and clinical breast cancer tissue samples. Accordingly, anti-sense oligonucleotide (ASO) targeting circPGR was proven to be effective in suppressing ER-positive breast cancer cell growth. Conclusions: These findings reveled that, besides the well-known messenger RNA (mRNA), microRNA (miRNA), long non-coding RNA (lncRNA) and enhancer RNA (eRNA) programs, estrogen also induced a circRNA program, and exemplified by circPGR, these estrogen-induced circRNAs were required for ER-positive breast cancer cell growth, providing a new class of therapeutic targets for ER-positive breast cancer.


Subject(s)
Biomarkers, Tumor/metabolism , Breast Neoplasms/pathology , Cell Cycle Proteins/metabolism , Estrogens/pharmacology , Gene Expression Regulation, Neoplastic/drug effects , RNA, Circular/genetics , Receptors, Progesterone/genetics , Animals , Apoptosis , Biomarkers, Tumor/genetics , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Cell Cycle , Cell Cycle Proteins/genetics , Cell Proliferation , Female , Gene Expression Profiling , Humans , Mice , Mice, Inbred BALB C , Mice, Nude , MicroRNAs/genetics , Prognosis , Receptors, Estrogen/genetics , Receptors, Estrogen/metabolism , Survival Rate , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
18.
Clin Transl Immunology ; 9(5): e01135, 2020 May.
Article in English | MEDLINE | ID: mdl-32373345

ABSTRACT

OBJECTIVES: Triple-negative breast cancer (TNBC) is well known for its strong invasiveness, rapid recurrence and poor prognosis. Immunotherapy, including chimeric antigen receptor-modified T (CAR-T) cells, has emerged as a promising tool to treat TNBC. The identification of a specific target tumor antigen and the design of an effective CAR are among the many challenges of CAR-T therapy. METHODS: We reported that epidermal growth factor receptor (EGFR) is highly expressed in TNBC and consequently designed an optimal third generation of CAR targeting EGFR. The efficacy of primary T lymphocytes infected with EGFR CAR lentivirus (EGFR CAR-T) against TNBC was evaluated both in vitro and in vivo. The signalling pathways activated in tumor and EGFR CAR-T cells were revealed by RNA sequencing analysis. RESULTS: Third-generation EGFR CAR-T cells exerted potent and specific suppression of TNBC cell growth in vitro, whereas limited cytotoxicity was observed towards normal breast epithelial cells or oestrogen receptor-positive breast cancer cells. This capability was further demonstrated in vivo in a xenograft mouse model, with minimal off-tumor cytotoxicity. Mechanistically, in vitro stimulation with TNBC cells induced the expansion of naïve-associated EGFR CAR-T cells and enhanced their persistence. Furthermore, EGFR CAR-T cells activated the interferon γ, granzyme-perforin-PARP and Fas-FADD-caspase signalling pathways in TNBC cells. CONCLUSION: We demonstrate that EGFR is a relevant immunotherapeutic target in TNBC, and EGFR CAR-T exhibits potent and specific antitumor activity against TNBC, suggesting the potential of this third-generation EGFR CAR-T as an immunotherapy tool to treat TNBC in the clinic.

19.
Theranostics ; 10(8): 3451-3473, 2020.
Article in English | MEDLINE | ID: mdl-32206101

ABSTRACT

While protein arginine methyltransferases (PRMTs) and PRMT-catalyzed protein methylation have been well-known to be involved in a myriad of biological processes, their functions and the underlying molecular mechanisms in cancers, particularly in estrogen receptor alpha (ERα)-positive breast cancers, remain incompletely understood. Here we focused on investigating PRMT4 (also called coactivator associated arginine methyltransferase 1, CARM1) in ERα-positive breast cancers due to its high expression and the associated poor prognosis. Methods: ChIP-seq and RNA-seq were employed to identify the chromatin-binding landscape and transcriptional targets of CARM1, respectively, in the presence of estrogen in ERα-positive MCF7 breast cancer cells. High-resolution mass spectrometry analysis of enriched peptides from anti-monomethyl- and anti-asymmetric dimethyl-arginine antibodies in SILAC labeled wild-type and CARM1 knockout cells were performed to globally map CARM1 methylation substrates. Cell viability was measured by MTS and colony formation assay, and cell cycle was measured by FACS analysis. Cell migration and invasion capacities were examined by wound-healing and trans-well assay, respectively. Xenograft assay was used to analyze tumor growth in vivo. Results: CARM1 was found to be predominantly and specifically recruited to ERα-bound active enhancers and essential for the transcriptional activation of cognate estrogen-induced genes in response to estrogen treatment. Global mapping of CARM1 substrates revealed that CARM1 methylated a large cohort of proteins with diverse biological functions, including regulation of intracellular estrogen receptor-mediated signaling, chromatin organization and chromatin remodeling. A large number of CARM1 substrates were found to be exclusively hypermethylated by CARM1 on a cluster of arginine residues. Exemplified by MED12, hypermethylation of these proteins by CARM1 served as a molecular beacon for recruiting coactivator protein, tudor-domain-containing protein 3 (TDRD3), to CARM1-bound active enhancers to activate estrogen/ERα-target genes. In consistent with its critical role in estrogen/ERα-induced gene transcriptional activation, CARM1 was found to promote cell proliferation of ERα-positive breast cancer cells in vitro and tumor growth in mice. Conclusions: our study uncovered a "hypermethylation" strategy utilized by enhancer-bound CARM1 in gene transcriptional regulation, and suggested that CARM1 can server as a therapeutic target for breast cancer treatment.


Subject(s)
Breast Neoplasms/metabolism , Enhancer Elements, Genetic , Estrogen Receptor alpha/metabolism , Gene Expression Regulation, Neoplastic , Protein-Arginine N-Methyltransferases/metabolism , Animals , Arginine/metabolism , Breast Neoplasms/genetics , Cell Proliferation , Cell Transformation, Neoplastic , Chromatin Immunoprecipitation Sequencing , Estrogens/metabolism , Female , Gene Knockout Techniques , Humans , MCF-7 Cells , Mediator Complex/metabolism , Methylation , Mice , Mice, Inbred BALB C , Mice, Nude , Protein Binding , Protein-Arginine N-Methyltransferases/genetics , Proteins/metabolism , RNA-Seq , Transcriptional Activation , Xenograft Model Antitumor Assays
20.
Asian J Androl ; 22(1): 79-87, 2020.
Article in English | MEDLINE | ID: mdl-31210146

ABSTRACT

The transition from spermatogonia to spermatocytes and the initiation of meiosis are key steps in spermatogenesis and are precisely regulated by a plethora of proteins. However, the underlying molecular mechanism remains largely unknown. Here, we report that Src homology domain tyrosine phosphatase 2 (Shp2; encoded by the protein tyrosine phosphatase, nonreceptor type 11 [Ptpn11] gene) is abundant in spermatogonia but markedly decreases in meiotic spermatocytes. Conditional knockout of Shp2 in spermatogonia in mice using stimulated by retinoic acid gene 8 (Stra8)-cre enhanced spermatogonial differentiation and disturbed the meiotic process. Depletion of Shp2 in spermatogonia caused many meiotic spermatocytes to die; moreover, the surviving spermatocytes reached the leptotene stage early at postnatal day 9 (PN9) and the pachytene stage at PN11-13. In preleptotene spermatocytes, Shp2 deletion disrupted the expression of meiotic genes, such as disrupted meiotic cDNA 1 (Dmc1), DNA repair recombinase rad51 (Rad51), and structural maintenance of chromosome 3 (Smc3), and these deficiencies interrupted spermatocyte meiosis. In GC-1 cells cultured in vitro, Shp2 knockdown suppressed the retinoic acid (RA)-induced phosphorylation of extracellular-regulated protein kinase (Erk) and protein kinase B (Akt/PKB) and the expression of target genes such as synaptonemal complex protein 3 (Sycp3) and Dmc1. Together, these data suggest that Shp2 plays a crucial role in spermatogenesis by governing the transition from spermatogonia to spermatocytes and by mediating meiotic progression through regulating gene transcription, thus providing a potential treatment target for male infertility.


Subject(s)
Meiosis/genetics , Protein Tyrosine Phosphatase, Non-Receptor Type 11/genetics , Spermatocytes/metabolism , Spermatogenesis/genetics , Spermatogonia/metabolism , Animals , Cell Cycle Proteins/genetics , Cell Line , Cell Survival , Chondroitin Sulfate Proteoglycans/genetics , Chromosomal Proteins, Non-Histone/genetics , Gene Expression Regulation , Gene Knockdown Techniques , Infertility, Male , Male , Mice , Mice, Knockout , Mice, Transgenic , Phosphate-Binding Proteins/genetics , Rad51 Recombinase/genetics , Real-Time Polymerase Chain Reaction , Spermatocytes/cytology , Spermatogonia/cytology
SELECTION OF CITATIONS
SEARCH DETAIL
...