Project description:PyMT tumor cells with indicated status of Mtdh and Snd1 were treated with camptothecin (CPT) and the transcirptome profiles were determined and compared two sets of experiments: (1) vector control vs Snd1-KD under CPT treament (2) PyMT/Mtdh-KO cells reconstituted with either WT or Snd1-binding deficient mutant Mtdh (W391D) under CPT treatment
Project description:Previous studies discovered that MTDH frequently amplifies and overexpresses in breast cancer in human patients and is strongly associated with higher metastasis and treatment failure and thereby leads to poor prognosis. In mouse mammary tumor models, knockout of Mtdh substantially reduces tumor incidence and suppresess metastasis. Furthermore, Mtdh interact with Snd1 and the interaction appears essential for its tumor promoting function. To develop novel therapeutics targeting Mtdh function, small molecular compound to disrupt the Mtdh-Snd1 interaction was identified by high throughput screen. To further elucidate the mechanism of MTDH targeting caused anti-tumor activity and to confirm the action mode of the small molecular compound C26A6 as a Mtdh-Snd1 disruptor, transcriptome changes in mouse mammary tumors following treatments of C26A6 and acute induction of Mtdh knockout by Tamoxifen treatment were investigated using next generation sequencing.
Project description:Therapeutic targeting MTDH-SND1 interaction Suppresses Breast Cancer Progression and Metastasis (GSE159764). To further elucidate the tumor intrinsic effects of the targeting and the adverse effects on normal mammary epithelial cells Mouse mammary tumor cells and normal mammary epithelial cells were isolated from transgenic mouse models and cultured in vitro 3D spheroids system. MMTV-PyMT tumor cells from cKO mouse in tumorsphere culture were treaed with tamoxifen to induce Mtdh KO, and compared to the mock treatment which maintain wild type Mtdh. Thus the tumor intrinsic effects can be determined Normal mammary epithelial cells were isolated from mouse mammary gland and cultured in vitro in mammosphere. The cells were treated with inhibitor C26A6 vs control and thus the adverse effects on normal MECs can be determined.
Project description:PyMT tumor cells with indicated status of Mtdh and Snd1 were treated with camptothecin (CPT) and the transcirptome profiles were determined and compared
Project description:ERG is a transcriptional factor, which is recombined with promoter of TMPRSS2 and prominently overexpressed in half of human prostate cancers. The mechanisms of ERG-mediated oncogenesis are not completely understood. We performed an unbiased Mass Spectrometry screen for ERG-binding proteins and found that ERG binds to MTDH/SND1 protein complex in prostate cancer cells. We determined that ERG binds to the SND1/MTDH protein complex via SND1 and this interaction plays a critical role in ERG-mediated cancer.
Project description:SND1 and its partner MTDH promote cancer and therapeutic resistance; however, the mechanisms responsible for their function and potential cooperation with other oncogenes are not completely understood. We report here that oncoprotein ERG binds to the SND1/MTDH protein complex via the Tudor domain of SND1. ERG is an ETS-domain transcriptional factor, which is recombined and overexpressed in approximately half of human prostate cancers. siRNA-mediated knockdowns and CRISPR-Cas9-mediated knockout of SND1 in human prostate epithelium cell lines revealed a critical role of SND1 in proliferation of ERG-overexpressing prostate epithelial cells. Transcriptional analysis of ERG-positive human prostate cancer cells demonstrated significant overlap between genes regulated by ERG and SND1. Mechanistically, we found that ERG promoted nuclear localization of SND1/MTDH. Significantly, forced nuclear localization of SND1 by addition of exogenous nuclear localization sequences (NLS) prominently increased its growth promoting function irrespective of the status of ERG expression. To determine if SND1 is necessary for prostate cancer tumorigenesis in vivo, we generated mice with prostate-epithelium-specific deletion of Snd1. We found that inactivation of Snd1 did not impact normal prostate gland homeostasis. However, prostate epithelium-specific deletion of Snd1 in autochthonous mouse model of prostate cancer (PB-Cre/ERG/PTENflox/flox mice) showed greatly reduced invasive cancer growth and tumor burden. Moreover, gene expression analysis revealed a significant overlap between in vivo prostate transcriptional signatures of ERG and Snd1. We conclude that SND1 plays a critical role in prostate tumorigenesis and targeting SND1 may represent a potential therapeutic target in prostate cancer.
Project description:To examine whether MTDH is a novel RNA binding protein and regulates either metabolism or translation of various mRNAs, we performed a RNA-binding protein immunoprecipitation (RIP) with MTDH and IgG antibodies, and the resulting immunoprecipitated RNA was subjected to a microarray to identify transcripts associating with MTDH. In addition we tested the effect of PI3K inhibition using BEZ235 (a dual PI3K/mTOR inhibitor) on the association of MTDH with target mRNAs. The microarray was performed on three biological triplicates as well as three experimental triplicates of immunoprecipitated MTDH and IgG in Hec50co endometrial cancer cells. Magna RIP (RNA-binding protein immunoprecipitation, Millipore) Kit and microarray were used to immunoprecipitate MTDH associated RNAs and to identify mRNAs that associate with MTDH in the absence or presence of 100nM BEZ235 (LC Labs). Fold changes represent immunoprecipitated MTDH RNA compared to IgG immunoprecipitated RNA. Representative mRNAs associated with MTDH and the effect of BEZ235 on the association of MTDH with mRNAs are shown.
