The Experts below are selected from a list of 498 Experts worldwide ranked by ideXlab platform

Kimberly K Leslie - One of the best experts on this subject based on the ideXlab platform.

  • abstract 4852 induction of hrd by targeting g9a and MTDH in dna repair proficient endometrial cancer cells
    Cancer Research, 2018
    Co-Authors: Xiangbing Meng, Shujie Yang, Yuping Zhang, Sudartip Areecheewaku, Zihan Wang, Aliasger K Salem, Kimberly K Leslie
    Abstract:

    The homologous recombination repair (HRR) pathway is required for high-fidelity repair of double-strand DNA breaks. Cancer cells with HRR deficiency due to somatic BRCA1 or BRCA2 mutations are sensitive to platinum agents and targeted therapy with PARP inhibitors. Endometrial cancer is the most common cancer of the female reproductive system. DNA damage agents are commonly used in treatment but tumors often develop resistance. Metadherin (MTDH) has been shown to be amplified in a wide range of solid tumors as well as in leukemia and lymphoma. Overexpression of MTDH is correlated with angiogenesis, metastasis, and chemoresistance. Histone lysine N-methyl-transferase G9a catalyzes the demethylation of histone H3 at lysine residue 9 (H3K9) resulting in a repressive histone modification. The objective of this study is to validate the function of MTDH and G9a in HRR and test the potential to target MTDH or G9a to increase drug sensitivity. p21 expression was induced when G9a was depleted. DNA damage induced MTDH expression at 4 hours after 8Gy γ-irradiation in the well validated endometrial adenocarcinoma cell line Ishikawa H. However, induction of MTDH protein expression by the same radiation dosage was reduced when G9a was depleted. The G9a inhibitor UNC0642 itself can also induce the expression of MTDH after 24 hours treatment. Ishikawa parental cells and two Ishikawa sub-cell lines in which G9a was depleted by CRISPR were tested for the DNA damage biomarker γH2Ax and Rad51 foci formation at 4 hours following 8Gy irradiation. G9a depletion was shown to decrease Rad51 foci formation and to increase the formation of γH2Ax foci. Two natural products, Celastrol and Pristimerim were found to inhibit MTDH, FANCD2 and FANCI protein levels, which may be used to induce BRCA-ness in homologous recombination repair proficient cancer cells. G9a depletion results in the reduction of irradiation-induced Rad51 foci formation and an increase of irradiation-induced γH2Ax foci formation. We suggest that G9a depletion can increase cancer cell sensitivity to DNA damage agents. MTDH is induced by DNA damage and is a G9a inhibitor. MTDH depletion causes reduction of irradiation-induced Rad51 foci. This study is supported by the University of Iowa Department of Obstetrics and Gynecology Research Development Fund, NIH grant R01CA99908 and R01CA184101. Citation Format: Xiangbing Meng, Shujie Yang, Jianling Bi, Yiyang Li, Yuping Zhang, Sudartip Areecheewaku, Mary Li, Zihan Wang, Aliasger K. Salem, Kimberly K. Leslie. Induction of HRD by targeting G9a and MTDH in DNA repair proficient endometrial cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4852.

  • genetic deficiency of MTDH gene in mice causes male infertility via impaired spermatogenesis and alterations in the expression of small non coding rnas
    Journal of Biological Chemistry, 2015
    Co-Authors: Xiangbing Meng, Shujie Yang, Xinjun Wang, Yuping Zhang, Kristina W Thiel, Renee X Goodfellow, Yichen Jia, Henry D Reyes, Baoli Yang, Kimberly K Leslie
    Abstract:

    Abstract Increased expression of metadherin (MTDH, also known as AEG-1 and 3D3/LYRIC) has been associated with drug resistance, metastasis, and angiogenesis in a variety of cancers. However, the specific mechanisms through which MTDH is involved in these processes remain unclear. To uncover these mechanisms, we generated MTDH knock-out mice via a targeted disruption of exon 3. Homozygous MTDH knock-out mice are viable, but males are infertile. The homozygous male mice present with massive loss of spermatozoa as a consequence of meiotic failure. Accumulation of γ-H2AX in spermatocytes of homozygous MTDH knock-out mice confirms an increase in unrepaired DNA breaks. We also examined expression of the DNA repair protein Rad18, which is regulated by MTDH at the post-transcriptional level. In testes from MTDH exon 3-deficient mice, Rad18 foci were increased in the lumina of the seminiferous tubules. The Piwi-interacting RNA (piRNA)-interacting protein Mili was expressed at high levels in testes from MTDH knock-out mice. Accordingly, genome-wide small RNA deep sequencing demonstrated altered expression of piRNAs in the testes of MTDH knock-out mice as compared with wild type mice. In addition, we observed significantly reduced expression of microRNAs (miRNAs) including miR-16 and miR-19b, which are known to be significantly reduced in the semen of infertile men. In sum, our observations indicate a crucial role for MTDH in male fertility and the DNA repair mechanisms required for normal spermatogenesis.

  • drug resistance mediated by aeg 1 MTDH lyric
    Advances in Cancer Research, 2013
    Co-Authors: Xiangbing Meng, Kristina W Thiel, Kimberly K Leslie
    Abstract:

    AEG-1/MTDH/LYRIC has been shown to promote cancer progression and development. Overexpression of AEG-1/MTDH/LYRIC correlates with angiogenesis, metastasis, and chemoresistance to various chemotherapy agents in cancer cells originating from a variety of tissues. In this chapter, we focus on the role of AEG-1/MTDH/LYRIC in drug resistance. Mechanistic studies have shown that AEG-1/MTDH/LYRIC is involved in classical oncogenic pathways including Ha-Ras, myc, NFκB, and PI3K/Akt. AEG-1/MTDH/LYRIC also promotes protective autophagy by activating AMP kinase and autophagy-related gene 5. Another reported mechanism by which AEG-1/MTDH/LYRIC regulates drug resistance is by increasing loading of multidrug resistance gene (MDR) 1 mRNA to the polysome, thereby facilitating MDR1 protein translation. More recently, a novel function for AEG-1/MTDH/LYRIC as an RNA-binding protein was elucidated, which has the potential to impact expression of drug sensitivity or resistance genes. Finally, AEG-1/MTDH/LYRIC acts in microRNA-directed gene silencing via an interaction with staphylococcal nuclease and tudor domain containing 1, a component of the RNA-induced silencing complex. Altered microRNA expression and activity induced by AEG-1/MTDH/LYRIC represent an additional way that AEG-1/MTDH/LYRIC may cause drug resistance in cancer. The multiple functions of AEG-1/MTDH/LYRIC in drug resistance highlight that it is a viable target as an anticancer agent for a wide variety of cancers.

  • abstract 3053 identification of a novel cytoplasmic role for MTDH aeg 1 in chemoresistance as a rna binding protein
    Cancer Research, 2012
    Co-Authors: Xiangbing Meng, Danlin Zhu, Shujie Yang, Xinjun Wang, Zhi Xiong, Yuping Zhang, Kimberly K Leslie
    Abstract:

    Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL Overexpression of metadherin (MTDH/AEG-1) has been documented in many solid tumors and is implicated in metastasis and chemoresistance. MTDH has been detected at the plasma membrane as well as in the cytoplasm and nucleus, and the function of MTDH in these locales remains under investigation. In the nucleus, MTDH acts as a transcription co-factor to induce expression of chemoresistance-associated genes. However, MTDH is predominantly cytoplasmic in solid tumors, and this localization has been shown to correlate with poor prognosis. In this study, we used endometrial cancer cells as a model system to define a new role for MTDH in the cytoplasm. First, MTDH was primarily localized to the cytoplasm in endometrial cancer cells, and the N-terminal region of MTDH was required to maintain cytoplasmic localization. Depletion of cytoplasmic MTDH in endometrial cancer cells restored chemosensitivity to various DNA damaging agents including mitomycin C (MMC) and doxorubicin. Next, we identified novel binding partners for cytoplasmic MTDH, including ribosome protein RPL4, ribosome biogenesis-related protein NPM1, and a component of the RNA induced silencing complex SND1. Association of MTDH with these cytoplasmic proteins was disrupted by nuclease treatment, demonstrating that nucleic acid is required for the interaction of cytoplasmic MTDH with these RNA metabolism and processing proteins. Furthermore, RNA binding protein-chromatin IP (RIP-chIP) analysis demonstrated that MTDH interacted with multiple mRNAs, and treatment with the PI3K and mTOR dual inhibitor BEZ235 altered the pattern of mRNAs that associate with MTDH. Knockdown of MTDH promoted an increase in protein levels of some MTDH-associated mRNAs. Finally, increased stress granule formation was observed in MTDH knockdown cells in response to heat shock, suggesting that one mechanism by which MTDH promotes chemoresistance is prevention of stress granule formation. Taken together, our data identify MTDH as an active RNA binding protein in the cytoplasm of cancer cells. Our findings suggest that the RNA binding properties of cytoplasmic MTDH serve to regulate genes involved in the drug resistance and metastasis of tumors and highlight MTDH as an ideal target for future drug development. Acknowledgements: This work was supported by NIH Grant R01CA99908 to K.K.L., and in part by the Department of Obstetrics and Gynecology Research Development Fund, the Institutional Research Grant Number IRG-77-004-31 from the American Cancer Society to XM. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3053. doi:1538-7445.AM2012-3053

  • cytoplasmic metadherin MTDH provides survival advantage under conditions of stress by acting as rna binding protein
    Journal of Biological Chemistry, 2012
    Co-Authors: Xiangbing Meng, Danlin Zhu, Shujie Yang, Xinjun Wang, Zhi Xiong, Yuping Zhang, Pavla Brachova, Kimberly K Leslie
    Abstract:

    Overexpression of metadherin (MTDH) has been documented in many solid tumors and is implicated in metastasis and chemoresistance. MTDH has been detected at the plasma membrane as well as in the cytoplasm and nucleus, and the function of MTDH in these locales remains under investigation. In the nucleus, MTDH acts as a transcription co-factor to induce expression of chemoresistance-associated genes. However, MTDH is predominantly cytoplasmic in prostate tumors, and this localization correlates with poor prognosis. Herein, we used endometrial cancer cells as a model system to define a new role for MTDH in the cytoplasm. First, MTDH was primarily localized to the cytoplasm in endometrial cancer cells, and the N-terminal region of MTDH was required to maintain cytoplasmic localization. Next, we identified novel binding partners for cytoplasmic MTDH, including RNA-binding proteins and components of the RNA-induced silencing complex. Nucleic acids were required for the association of MTDH with these cytoplasmic proteins. Furthermore, MTDH interacted with and regulated protein expression of multiple mRNAs, such as PDCD10 and KDM6A. Depletion of cytoplasmic MTDH was associated with increased stress granule formation, reduced survival in response to chemotherapy and the tyrosine kinase inhibitor BIBF1120, Rad51 nuclear accumulation, and cell cycle arrest at G2/M. Finally, in vivo tumor formation was abrogated with knockdown of cytoplasmic MTDH. Taken together, our data identify a novel function for cytoplasmic MTDH as an RNA-binding protein. Our findings implicate cytoplasmic MTDH in cell survival and broad drug resistance via association with RNA and RNA-binding proteins.

Fang Guo - One of the best experts on this subject based on the ideXlab platform.

  • MTDH aeg 1 based dna vaccine suppresses metastasis and enhances chemosensitivity to paclitaxel in pelvic lymph node metastasis
    Biomedicine & Pharmacotherapy, 2015
    Co-Authors: Chun Zhang, Benjiang Qian, Changming Liu, Fang Guo, Miaochun Lin
    Abstract:

    Abstract Objective MTDH/AEG-1 could act as an oncogene by regulating cellular transformation, proliferation, invasion, metastasis, and angiogenesis. This study aims to explore the mechanism by which MTDH/AEG-1 inhibits cancer growth and metastasis and enhances chemosensitivity. Methods Mouse model was established using orally immunized mice exposed to attenuated Salmonella containing vectors carrying full length MTDH/AEG-1 gene, and we were able to enhance the immune response and inhibit the growth and metastasis of prostate cancer through activation of cellular and humoral immunities and induction of CD8+ T cells. Immunohistochemistry and TUNEL assay, CD4+ and CD8+ T cell analysis by flow cytometry, HE staining, RT-PCR analysis, Western-blot analysis and quantitative polymerase chain reaction were performed. Results The MTDH/AEG-1 gene vaccine induced the anti-tumor function of cytotoxic T lymphocytes and CD8+ T cells and inhibited tumor growth and metastasis of prostate cancer. In the therapy model, the MTDH/AEG-1 gene vaccine significantly enhanced chemosensitivity to paclitaxel, inhibited tumor growth, promoted tumor cell apoptosis, and prolonged the survival time of tumor-bearing mice without any apparent side effects. Conclusions Our results demonstrated that MTDH/AEG-1-based DNA vaccines could used for the treatment of prostate cancer in terms of the inhibition of tumor growth, the lifespan of tumor-bearing animals. Combined with chemotherapy, MTDH/AEG-1-based DNA vaccines may produce highly favorable outcomes in the prevention and treatment of prostate cancer, suggesting the immune efficacy of MTDH/AEG-1-based DNA should be further analyzed in other cancers.

  • MTDH aeg 1 based dna vaccine suppresses lung metastasis and enhances chemosensitivity to doxorubicin in breast cancer
    Cancer Immunology Immunotherapy, 2011
    Co-Authors: Benjiang Qian, Changming Liu, Fang Guo, Fei Yan, Qiaoling Liu, Yihui Lin, Yunping Luo
    Abstract:

    The gene MTDH/AEG-1 is overexpressed in more than 40% of breast cancer patients, and it is associated with poor clinical outcomes. Previous studies have indicated that MTDH/AEG-1 could promote metastatic lung-seeding and enhance chemoresistance. Therefore, MTDH/AEG-1 could be a candidate target against breast cancer lung metastasis. We demonstrated that MTDH/AEG-1-based DNA vaccine, delivered by attenuated Salmonella typhimurium, could evoke strong CD8+ cytotoxic-T-cell mediated immune responses against breast cancer. This vaccine showed anti-tumor growth and metastasis efficacy in a prophylactic setting. Importantly, in a therapeutic model, MTDH/AEG-1 vaccine was proved to increase chemosensitivity to doxorubicin and inhibit breast cancer lung metastasis. This vaccine could also prolong the life span of tumor-bearing mice without significant side effects in vivo. These results suggested that this novel DNA vaccine was effective in the inhibition of breast cancer growth and metastasis, and this vaccine in combination with chemotherapies offered new strategies for the clinical therapeutics of breast cancer metastasis.

Xiangbing Meng - One of the best experts on this subject based on the ideXlab platform.

  • abstract 4852 induction of hrd by targeting g9a and MTDH in dna repair proficient endometrial cancer cells
    Cancer Research, 2018
    Co-Authors: Xiangbing Meng, Shujie Yang, Yuping Zhang, Sudartip Areecheewaku, Zihan Wang, Aliasger K Salem, Kimberly K Leslie
    Abstract:

    The homologous recombination repair (HRR) pathway is required for high-fidelity repair of double-strand DNA breaks. Cancer cells with HRR deficiency due to somatic BRCA1 or BRCA2 mutations are sensitive to platinum agents and targeted therapy with PARP inhibitors. Endometrial cancer is the most common cancer of the female reproductive system. DNA damage agents are commonly used in treatment but tumors often develop resistance. Metadherin (MTDH) has been shown to be amplified in a wide range of solid tumors as well as in leukemia and lymphoma. Overexpression of MTDH is correlated with angiogenesis, metastasis, and chemoresistance. Histone lysine N-methyl-transferase G9a catalyzes the demethylation of histone H3 at lysine residue 9 (H3K9) resulting in a repressive histone modification. The objective of this study is to validate the function of MTDH and G9a in HRR and test the potential to target MTDH or G9a to increase drug sensitivity. p21 expression was induced when G9a was depleted. DNA damage induced MTDH expression at 4 hours after 8Gy γ-irradiation in the well validated endometrial adenocarcinoma cell line Ishikawa H. However, induction of MTDH protein expression by the same radiation dosage was reduced when G9a was depleted. The G9a inhibitor UNC0642 itself can also induce the expression of MTDH after 24 hours treatment. Ishikawa parental cells and two Ishikawa sub-cell lines in which G9a was depleted by CRISPR were tested for the DNA damage biomarker γH2Ax and Rad51 foci formation at 4 hours following 8Gy irradiation. G9a depletion was shown to decrease Rad51 foci formation and to increase the formation of γH2Ax foci. Two natural products, Celastrol and Pristimerim were found to inhibit MTDH, FANCD2 and FANCI protein levels, which may be used to induce BRCA-ness in homologous recombination repair proficient cancer cells. G9a depletion results in the reduction of irradiation-induced Rad51 foci formation and an increase of irradiation-induced γH2Ax foci formation. We suggest that G9a depletion can increase cancer cell sensitivity to DNA damage agents. MTDH is induced by DNA damage and is a G9a inhibitor. MTDH depletion causes reduction of irradiation-induced Rad51 foci. This study is supported by the University of Iowa Department of Obstetrics and Gynecology Research Development Fund, NIH grant R01CA99908 and R01CA184101. Citation Format: Xiangbing Meng, Shujie Yang, Jianling Bi, Yiyang Li, Yuping Zhang, Sudartip Areecheewaku, Mary Li, Zihan Wang, Aliasger K. Salem, Kimberly K. Leslie. Induction of HRD by targeting G9a and MTDH in DNA repair proficient endometrial cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4852.

  • genetic deficiency of MTDH gene in mice causes male infertility via impaired spermatogenesis and alterations in the expression of small non coding rnas
    Journal of Biological Chemistry, 2015
    Co-Authors: Xiangbing Meng, Shujie Yang, Xinjun Wang, Yuping Zhang, Kristina W Thiel, Renee X Goodfellow, Yichen Jia, Henry D Reyes, Baoli Yang, Kimberly K Leslie
    Abstract:

    Abstract Increased expression of metadherin (MTDH, also known as AEG-1 and 3D3/LYRIC) has been associated with drug resistance, metastasis, and angiogenesis in a variety of cancers. However, the specific mechanisms through which MTDH is involved in these processes remain unclear. To uncover these mechanisms, we generated MTDH knock-out mice via a targeted disruption of exon 3. Homozygous MTDH knock-out mice are viable, but males are infertile. The homozygous male mice present with massive loss of spermatozoa as a consequence of meiotic failure. Accumulation of γ-H2AX in spermatocytes of homozygous MTDH knock-out mice confirms an increase in unrepaired DNA breaks. We also examined expression of the DNA repair protein Rad18, which is regulated by MTDH at the post-transcriptional level. In testes from MTDH exon 3-deficient mice, Rad18 foci were increased in the lumina of the seminiferous tubules. The Piwi-interacting RNA (piRNA)-interacting protein Mili was expressed at high levels in testes from MTDH knock-out mice. Accordingly, genome-wide small RNA deep sequencing demonstrated altered expression of piRNAs in the testes of MTDH knock-out mice as compared with wild type mice. In addition, we observed significantly reduced expression of microRNAs (miRNAs) including miR-16 and miR-19b, which are known to be significantly reduced in the semen of infertile men. In sum, our observations indicate a crucial role for MTDH in male fertility and the DNA repair mechanisms required for normal spermatogenesis.

  • drug resistance mediated by aeg 1 MTDH lyric
    Advances in Cancer Research, 2013
    Co-Authors: Xiangbing Meng, Kristina W Thiel, Kimberly K Leslie
    Abstract:

    AEG-1/MTDH/LYRIC has been shown to promote cancer progression and development. Overexpression of AEG-1/MTDH/LYRIC correlates with angiogenesis, metastasis, and chemoresistance to various chemotherapy agents in cancer cells originating from a variety of tissues. In this chapter, we focus on the role of AEG-1/MTDH/LYRIC in drug resistance. Mechanistic studies have shown that AEG-1/MTDH/LYRIC is involved in classical oncogenic pathways including Ha-Ras, myc, NFκB, and PI3K/Akt. AEG-1/MTDH/LYRIC also promotes protective autophagy by activating AMP kinase and autophagy-related gene 5. Another reported mechanism by which AEG-1/MTDH/LYRIC regulates drug resistance is by increasing loading of multidrug resistance gene (MDR) 1 mRNA to the polysome, thereby facilitating MDR1 protein translation. More recently, a novel function for AEG-1/MTDH/LYRIC as an RNA-binding protein was elucidated, which has the potential to impact expression of drug sensitivity or resistance genes. Finally, AEG-1/MTDH/LYRIC acts in microRNA-directed gene silencing via an interaction with staphylococcal nuclease and tudor domain containing 1, a component of the RNA-induced silencing complex. Altered microRNA expression and activity induced by AEG-1/MTDH/LYRIC represent an additional way that AEG-1/MTDH/LYRIC may cause drug resistance in cancer. The multiple functions of AEG-1/MTDH/LYRIC in drug resistance highlight that it is a viable target as an anticancer agent for a wide variety of cancers.

  • abstract 3053 identification of a novel cytoplasmic role for MTDH aeg 1 in chemoresistance as a rna binding protein
    Cancer Research, 2012
    Co-Authors: Xiangbing Meng, Danlin Zhu, Shujie Yang, Xinjun Wang, Zhi Xiong, Yuping Zhang, Kimberly K Leslie
    Abstract:

    Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL Overexpression of metadherin (MTDH/AEG-1) has been documented in many solid tumors and is implicated in metastasis and chemoresistance. MTDH has been detected at the plasma membrane as well as in the cytoplasm and nucleus, and the function of MTDH in these locales remains under investigation. In the nucleus, MTDH acts as a transcription co-factor to induce expression of chemoresistance-associated genes. However, MTDH is predominantly cytoplasmic in solid tumors, and this localization has been shown to correlate with poor prognosis. In this study, we used endometrial cancer cells as a model system to define a new role for MTDH in the cytoplasm. First, MTDH was primarily localized to the cytoplasm in endometrial cancer cells, and the N-terminal region of MTDH was required to maintain cytoplasmic localization. Depletion of cytoplasmic MTDH in endometrial cancer cells restored chemosensitivity to various DNA damaging agents including mitomycin C (MMC) and doxorubicin. Next, we identified novel binding partners for cytoplasmic MTDH, including ribosome protein RPL4, ribosome biogenesis-related protein NPM1, and a component of the RNA induced silencing complex SND1. Association of MTDH with these cytoplasmic proteins was disrupted by nuclease treatment, demonstrating that nucleic acid is required for the interaction of cytoplasmic MTDH with these RNA metabolism and processing proteins. Furthermore, RNA binding protein-chromatin IP (RIP-chIP) analysis demonstrated that MTDH interacted with multiple mRNAs, and treatment with the PI3K and mTOR dual inhibitor BEZ235 altered the pattern of mRNAs that associate with MTDH. Knockdown of MTDH promoted an increase in protein levels of some MTDH-associated mRNAs. Finally, increased stress granule formation was observed in MTDH knockdown cells in response to heat shock, suggesting that one mechanism by which MTDH promotes chemoresistance is prevention of stress granule formation. Taken together, our data identify MTDH as an active RNA binding protein in the cytoplasm of cancer cells. Our findings suggest that the RNA binding properties of cytoplasmic MTDH serve to regulate genes involved in the drug resistance and metastasis of tumors and highlight MTDH as an ideal target for future drug development. Acknowledgements: This work was supported by NIH Grant R01CA99908 to K.K.L., and in part by the Department of Obstetrics and Gynecology Research Development Fund, the Institutional Research Grant Number IRG-77-004-31 from the American Cancer Society to XM. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3053. doi:1538-7445.AM2012-3053

  • cytoplasmic metadherin MTDH provides survival advantage under conditions of stress by acting as rna binding protein
    Journal of Biological Chemistry, 2012
    Co-Authors: Xiangbing Meng, Danlin Zhu, Shujie Yang, Xinjun Wang, Zhi Xiong, Yuping Zhang, Pavla Brachova, Kimberly K Leslie
    Abstract:

    Overexpression of metadherin (MTDH) has been documented in many solid tumors and is implicated in metastasis and chemoresistance. MTDH has been detected at the plasma membrane as well as in the cytoplasm and nucleus, and the function of MTDH in these locales remains under investigation. In the nucleus, MTDH acts as a transcription co-factor to induce expression of chemoresistance-associated genes. However, MTDH is predominantly cytoplasmic in prostate tumors, and this localization correlates with poor prognosis. Herein, we used endometrial cancer cells as a model system to define a new role for MTDH in the cytoplasm. First, MTDH was primarily localized to the cytoplasm in endometrial cancer cells, and the N-terminal region of MTDH was required to maintain cytoplasmic localization. Next, we identified novel binding partners for cytoplasmic MTDH, including RNA-binding proteins and components of the RNA-induced silencing complex. Nucleic acids were required for the association of MTDH with these cytoplasmic proteins. Furthermore, MTDH interacted with and regulated protein expression of multiple mRNAs, such as PDCD10 and KDM6A. Depletion of cytoplasmic MTDH was associated with increased stress granule formation, reduced survival in response to chemotherapy and the tyrosine kinase inhibitor BIBF1120, Rad51 nuclear accumulation, and cell cycle arrest at G2/M. Finally, in vivo tumor formation was abrogated with knockdown of cytoplasmic MTDH. Taken together, our data identify a novel function for cytoplasmic MTDH as an RNA-binding protein. Our findings implicate cytoplasmic MTDH in cell survival and broad drug resistance via association with RNA and RNA-binding proteins.

Paul B Fisher - One of the best experts on this subject based on the ideXlab platform.

  • aeg 1 MTDH lyric a promiscuous protein partner critical in cancer obesity and cns diseases
    Advances in Cancer Research, 2016
    Co-Authors: Luni Emdad, Devanand Sarkar, Swadesh K Das, Timothy P Kegelman, Dongchul Kang, Seokgeun Lee, Paul B Fisher
    Abstract:

    Since its original discovery in 2002, AEG-1/MTDH/LYRIC has emerged as a primary regulator of several diseases including cancer, inflammatory diseases, and neurodegenerative diseases. AEG-1/MTDH/LYRIC has emerged as a key contributory molecule in almost every aspect of cancer progression, including uncontrolled cell growth, evasion of apoptosis, increased cell migration and invasion, angiogenesis, chemoresistance, and metastasis. Additionally, recent studies highlight a seminal role of AEG-1/MTDH/LYRIC in neurodegenerative diseases and obesity. By interacting with multiple protein partners, AEG-1/MTDH/LYRIC plays multifaceted roles in the pathogenesis of a wide variety of diseases. This review discusses the current state of understanding of AEG-1/MTDH/LYRIC regulation and function in cancer and other diseases with a focus on its association/interaction with several pivotal protein partners.

  • aeg 1 MTDH lyric clinical significance
    Advances in Cancer Research, 2013
    Co-Authors: Devanand Sarkar, Paul B Fisher
    Abstract:

    "Gain-of-function" and "loss-of-function" studies in human cancer cells and analysis of a transgenic mouse model have convincingly established that AEG-1/MTDH/LYRIC performs a seminal role in regulating proliferation, invasion, angiogenesis, metastasis, and chemoresistance, the salient defining hallmarks of cancer. These observations are strongly buttressed by clinicopathologic correlations of AEG-1/MTDH/LYRIC expression in a diverse array of cancers distinguishing AEG-1/MTDH/LYRIC as an independent biomarker for highly aggressive metastatic disease with poor prognosis. AEG-1/MTDH/LYRIC has been shown to be a marker predicting response to chemotherapy, and serum anti-AEG-1/MTDH/LYRIC antibody titer also serves as a predictor of advanced stages of aggressive cancer. However, inconsistent findings have been reported regarding the localization of AEG-1/MTDH/LYRIC protein in the nucleus or cytoplasm of cancer cells and the utility of nuclear or cytoplasmic AEG-1/MTDH/LYRIC to predict the course and prognosis of disease. This chapter provides a comprehensive analysis of the existing literature to emphasize the common and conflicting findings relative to the clinical significance of AEG-1/MTDH/LYRIC in cancer.

  • aeg 1 MTDH lyric signaling pathways downstream genes interacting proteins and regulation of tumor angiogenesis
    Advances in Cancer Research, 2013
    Co-Authors: Luni Emdad, Devanand Sarkar, Swadesh K Das, Santanu Dasgupta, Paul B Fisher
    Abstract:

    Astrocyte elevated gene-1 (AEG-1), also known as metadherin (MTDH) and lysine-rich CEACAM1 coisolated (LYRIC), was initially cloned in 2002. AEG-1/MTDH/LYRIC has emerged as an important oncogene that is overexpressed in multiple types of human cancer. Expanded research on AEG-1/MTDH/LYRIC has established a functional role of this molecule in several crucial aspects of tumor progression, including transformation, proliferation, cell survival, evasion of apoptosis, migration and invasion, metastasis, angiogenesis, and chemoresistance. The multifunctional role of AEG-1/MTDH/LYRIC in tumor development and progression is associated with a number of signaling cascades, and recent studies identified several important interacting partners of AEG-1/MTDH/LYRIC in regulating cancer promotion and other biological functions. This review evaluates the current literature on AEG-1/MTDH/LYRIC function relative to signaling changes, interacting partners, and angiogenesis and highlights new perspectives of this molecule, indicating its potential as a significant target for the clinical treatment of various cancers and other diseases.

  • aeg 1 MTDH lyric the beginning initial cloning structure expression profile and regulation of expression
    Advances in Cancer Research, 2013
    Co-Authors: Seokgeun Lee, Devanand Sarkar, Dongchul Kang, Rob Desalle, Paul B Fisher
    Abstract:

    Since its initial identification as a HIV-1-inducible gene in 2002, astrocyte elevated gene-1 (AEG-1), subsequently cloned as metadherin (MTDH) and lysine-rich CEACAM1 coisolated (LYRIC), has emerged over the past 10 years as an important oncogene providing a valuable prognostic marker in patients with various cancers. Recent studies demonstrate that AEG-1/MTDH/LYRIC is a pleiotropic protein that can localize in the cell membrane, cytoplasm, endoplasmic reticulum (ER), nucleus, and nucleolus, and contributes to diverse signaling pathways such as PI3K–AKT, NF-κB, MAPK, and Wnt. In addition to tumorigenesis, this multifunctional protein is implicated in various physiological and pathological processes including development, neurodegeneration, and inflammation. The present review focuses on the discovery of AEG-1/MTDH/LYRIC and conceptualizes areas of future direction for this intriguing gene. We begin by describing how AEG-1, MTDH, and LYRIC were initially identified by different research groups and then discuss AEG-1 structure, functions, localization, and evolution. We conclude with a discussion of the expression profile of AEG-1/MTDH/LYRIC in the context of cancer, neurological disorders, inflammation, and embryogenesis, and discuss how AEG-1/MTDH/LYRIC is regulated. This introductory discussion of AEG-1/MTDH/LYRIC will serve as the basis for the detailed discussions in other chapters of the unique properties of this intriguing molecule.

Devanand Sarkar - One of the best experts on this subject based on the ideXlab platform.

  • aeg 1 MTDH lyric a promiscuous protein partner critical in cancer obesity and cns diseases
    Advances in Cancer Research, 2016
    Co-Authors: Luni Emdad, Devanand Sarkar, Swadesh K Das, Timothy P Kegelman, Dongchul Kang, Seokgeun Lee, Paul B Fisher
    Abstract:

    Since its original discovery in 2002, AEG-1/MTDH/LYRIC has emerged as a primary regulator of several diseases including cancer, inflammatory diseases, and neurodegenerative diseases. AEG-1/MTDH/LYRIC has emerged as a key contributory molecule in almost every aspect of cancer progression, including uncontrolled cell growth, evasion of apoptosis, increased cell migration and invasion, angiogenesis, chemoresistance, and metastasis. Additionally, recent studies highlight a seminal role of AEG-1/MTDH/LYRIC in neurodegenerative diseases and obesity. By interacting with multiple protein partners, AEG-1/MTDH/LYRIC plays multifaceted roles in the pathogenesis of a wide variety of diseases. This review discusses the current state of understanding of AEG-1/MTDH/LYRIC regulation and function in cancer and other diseases with a focus on its association/interaction with several pivotal protein partners.

  • aeg 1 MTDH lyric clinical significance
    Advances in Cancer Research, 2013
    Co-Authors: Devanand Sarkar, Paul B Fisher
    Abstract:

    "Gain-of-function" and "loss-of-function" studies in human cancer cells and analysis of a transgenic mouse model have convincingly established that AEG-1/MTDH/LYRIC performs a seminal role in regulating proliferation, invasion, angiogenesis, metastasis, and chemoresistance, the salient defining hallmarks of cancer. These observations are strongly buttressed by clinicopathologic correlations of AEG-1/MTDH/LYRIC expression in a diverse array of cancers distinguishing AEG-1/MTDH/LYRIC as an independent biomarker for highly aggressive metastatic disease with poor prognosis. AEG-1/MTDH/LYRIC has been shown to be a marker predicting response to chemotherapy, and serum anti-AEG-1/MTDH/LYRIC antibody titer also serves as a predictor of advanced stages of aggressive cancer. However, inconsistent findings have been reported regarding the localization of AEG-1/MTDH/LYRIC protein in the nucleus or cytoplasm of cancer cells and the utility of nuclear or cytoplasmic AEG-1/MTDH/LYRIC to predict the course and prognosis of disease. This chapter provides a comprehensive analysis of the existing literature to emphasize the common and conflicting findings relative to the clinical significance of AEG-1/MTDH/LYRIC in cancer.

  • aeg 1 MTDH lyric in liver cancer
    Advances in Cancer Research, 2013
    Co-Authors: Devanand Sarkar
    Abstract:

    Hepatocellular carcinoma (HCC) is a highly virulent malignancy with diverse etiology. Identification of a common mediator of aggressive progression of HCC would be extremely beneficial not only for diagnostic/prognostic purposes but also for developing targeted therapies. AEG-1/MTDH/LYRIC gene is amplified in human HCC patients, and overexpression of AEG-1/MTDH/LYRIC has been identified in a high percentage of both hepatitis B virus and hepatitis C virus positive HCC cases, suggesting its key role in regulating hepatocarcinogenesis. Important insights into the molecular mechanisms mediating oncogenic properties of AEG-1/MTDH/LYRIC, especially regulating chemoresistance, angiogenesis, and metastasis, have been obtained from studies using HCC model. Additionally, analysis of HCC model has facilitated the identification of AEG-1/MTDH/LYRIC downstream genes and interacting proteins, thereby unraveling novel players regulating HCC development and progression leading to the development of novel interventional strategies. Characterization of a hepatocyte-specific AEG-1/MTDH/LYRIC transgenic mouse (Alb/AEG-1) has revealed novel aspects of AEG-1/MTDH/LYRIC function in in vivo contexts. Combination of AEG-1/MTDH/LYRIC inhibition and chemotherapy has documented significant efficacy in abrogating human HCC xenografts in nude mice indicating the need for developing effective AEG-1/MTDH/LYRIC inhibition strategies to obtain objective response and survival benefits in terminal HCC patients.

  • aeg 1 MTDH lyric signaling pathways downstream genes interacting proteins and regulation of tumor angiogenesis
    Advances in Cancer Research, 2013
    Co-Authors: Luni Emdad, Devanand Sarkar, Swadesh K Das, Santanu Dasgupta, Paul B Fisher
    Abstract:

    Astrocyte elevated gene-1 (AEG-1), also known as metadherin (MTDH) and lysine-rich CEACAM1 coisolated (LYRIC), was initially cloned in 2002. AEG-1/MTDH/LYRIC has emerged as an important oncogene that is overexpressed in multiple types of human cancer. Expanded research on AEG-1/MTDH/LYRIC has established a functional role of this molecule in several crucial aspects of tumor progression, including transformation, proliferation, cell survival, evasion of apoptosis, migration and invasion, metastasis, angiogenesis, and chemoresistance. The multifunctional role of AEG-1/MTDH/LYRIC in tumor development and progression is associated with a number of signaling cascades, and recent studies identified several important interacting partners of AEG-1/MTDH/LYRIC in regulating cancer promotion and other biological functions. This review evaluates the current literature on AEG-1/MTDH/LYRIC function relative to signaling changes, interacting partners, and angiogenesis and highlights new perspectives of this molecule, indicating its potential as a significant target for the clinical treatment of various cancers and other diseases.

  • aeg 1 MTDH lyric the beginning initial cloning structure expression profile and regulation of expression
    Advances in Cancer Research, 2013
    Co-Authors: Seokgeun Lee, Devanand Sarkar, Dongchul Kang, Rob Desalle, Paul B Fisher
    Abstract:

    Since its initial identification as a HIV-1-inducible gene in 2002, astrocyte elevated gene-1 (AEG-1), subsequently cloned as metadherin (MTDH) and lysine-rich CEACAM1 coisolated (LYRIC), has emerged over the past 10 years as an important oncogene providing a valuable prognostic marker in patients with various cancers. Recent studies demonstrate that AEG-1/MTDH/LYRIC is a pleiotropic protein that can localize in the cell membrane, cytoplasm, endoplasmic reticulum (ER), nucleus, and nucleolus, and contributes to diverse signaling pathways such as PI3K–AKT, NF-κB, MAPK, and Wnt. In addition to tumorigenesis, this multifunctional protein is implicated in various physiological and pathological processes including development, neurodegeneration, and inflammation. The present review focuses on the discovery of AEG-1/MTDH/LYRIC and conceptualizes areas of future direction for this intriguing gene. We begin by describing how AEG-1, MTDH, and LYRIC were initially identified by different research groups and then discuss AEG-1 structure, functions, localization, and evolution. We conclude with a discussion of the expression profile of AEG-1/MTDH/LYRIC in the context of cancer, neurological disorders, inflammation, and embryogenesis, and discuss how AEG-1/MTDH/LYRIC is regulated. This introductory discussion of AEG-1/MTDH/LYRIC will serve as the basis for the detailed discussions in other chapters of the unique properties of this intriguing molecule.