ABSTRACT
Epithelial to Mesenchymal Transition (EMT) is a normal cellular process that is also triggered during cancer progression and metastasis. EMT induces cellular and microenviromental changes, resulting in loss of epithelial features and acquisition of mesenchymal phenotypes. The growth factor TGFß and the transcription factor SNAIL1 (SNAIL) have been described as inducers of EMT. Here, we carried out an EMT model with non-tumorigenic cell line MCF-10A induced with the TGFß2 specific isoform of TGF protein family. The model was validated by molecular, morphological and functional experiments and showed correlation with the up-regulation of SNAIL. In order to identify additional regulators of EMT in this non-tumorigenic model, we explored quantitative proteomics, which revealed the Ubiquitin carboxyl-terminal hydrolase 47 (USP47) as one of the top up-regulated proteins. USP47 has a known role in cell growth and genome integrity, but not previously correlated to EMT. After validating USP47 alterations using MRM and antibody-based assays, we demonstrated that the chemical inhibition of USP47 with the inhibitor P5091 reduced expression of EMT markers and reverted morphological changes in MCF-10A cells undergoing EMT. These results support the involvement of USP47 in our EMT model as well as potential applications of deubiquitinases as therapeutic targets for cancer progression management. BIOLOGICAL SIGNIFICANCE: Metastasis is responsible for most cancer-associated mortality. Additionally, metastasis requires special attention, as the cellular transformations make treatment at this stage very difficult or occasionally impossible. Early steps in cancer metastasis involve the ability to detach from the solid tumor mass and invade the surrounding stromal tissues through cohesive migration, or a mesenchymal or amoeboid invasion. One of the first steps for metastatic cascade is denominated epithelial to mesenchymal transition (EMT), which can be triggered by different factors. Here, our efforts were directed to better understand this process and identify new pathways that contributes for acquisition of EMT, mainly focused on post translational modifications related to ubiquitin proteasome system. Our model of EMT induction by TGFß2 mimics early stage of metastatic cancer in epithelial breast cells and a proteomic study carried out for such model demonstrates that the deubiquitinase enzyme USP47 acts in SNAIL stabilization, one of the most important transcription factors for EMT phenotype acquisition and consequent metastasis. In addition, the inhibiton of USP47 with P5091, reverted the EMT phenotype. Together the knowledge of such processes of cancer progression and regulation can help in designing new strategies for combined therapies for control of cancer in early stages.
Subject(s)
Epithelial-Mesenchymal Transition , Proteomics , Cell Line, Tumor , Cell Movement , Humans , Neoplasm Invasiveness , Transcription Factors , Transforming Growth Factor beta2 , Ubiquitin Thiolesterase , Ubiquitin-Specific ProteasesABSTRACT
The effects of intrauterine exposure to 17ß-oestradiol (E2) are well studied for the male prostate and there are accumulating evidences that the exposure to high dosages leads to a hypomorphic development. However, there is a lack of information about the effects of intrauterine exposure to E2 in the prostate of rodent females, and such research becomes relevant in view of the presence of functional prostate in a proportion of women, and the morphophysiological similarities between the prostate of female rodents and the prostate of women. This study uses histochemical, immunohistochemical, immunofluorescence and three-dimensional (3D) reconstruction techniques to evaluate the effects of intrauterine exposure to E2 (500 BW/d) on neonatal prostate development in both male and female gerbils. It was verified that intrauterine exposure to E2 promotes epithelial proliferation and growth of prostatic budding in females, whereas in males the prostatic budding shows hypomorphic growth in the VMP (Ventral Mesenchymal Pad) as well as reduced epithelial proliferation. Together, the data demonstrate that intrauterine exposure to E2 causes different effects on male and female prostates of the gerbil even at the early postnatal development of the gland.