In melanoma and other cancers, invasion, epithelial-to-mesenchymal transition, metastasis and cancer stem cell maintenance are regulated by transcription factors including the Snail family. Slug (Snail2) protein generally supports migration and apoptosis resistance. However, its role in melanoma is not completely understood. The present study investigated the transcriptional regulation of the SLUG gene in melanoma. It demonstrated that SLUG is under the control of the Hedgehog/GLI signaling pathway and is activated predominantly by the transcription factor GLI2. The SLUG gene promoter contains a high number of GLI-binding sites. Slug expression is activated by GLI factors in reporter assays and inhibited by GANT61 (GLI inhibitor) and cyclopamine (SMO inhibitor). SLUG mRNA levels are lowered by GANT61 as assessed by reverse transcription-quantitative PCR. Chromatin immunoprecipitation revealed abundant binding of factors GLI1-3 in the four subregions of the proximal SLUG promoter. Notably, melanoma-associated transcription factor (MITF) is an imperfect activator of the SLUG promoter in reporter assays, and downregulation of MITF had no effect on endogenous Slug protein levels. Immunohistochemical analysis confirmed the above findings and showed MITF-negative regions in metastatic melanoma that were positive for GLI2 and Slug. Taken together, the results demonstrated a previously unrecognized transcriptional activation mechanism of the SLUG gene, which may represent its main regulation of expression in melanoma cells.

• Klíčová slova
• GLI family zinc finger, Hedgehog signaling, Slug, melanoma, melanoma-associated transcription factor,
• MeSH
• apoptóza MeSH
• lidé MeSH
• melanom * genetika   MeSH
• proteiny hedgehog * genetika   MeSH
• signální transdukce MeSH
• transkripční faktory genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• proteiny hedgehog * MeSH
• transkripční faktory MeSH

Prostate cancer (PCa) is the second leading cause of cancer-related deaths in men in Western countries, and there is still an urgent need for a better understanding of PCa progression to inspire new treatment strategies. Skp2 is a substrate-recruiting component of the E3 ubiquitin ligase complex, whose activity is regulated through neddylation. Slug is a transcriptional repressor involved in the epithelial-to-mesenchymal transition, which may contribute to therapy resistance. Although Skp2 has previously been associated with a mesenchymal phenotype and prostate cancer progression, the relationship with Slug deserves further elucidation. We have previously shown that a high Gleason score (≥8) is associated with higher Skp2 and lower E-cadherin expression. In this study, significantly increased expression of Skp2, AR, and Slug, along with E-cadherin downregulation, was observed in primary prostate cancer in patients who already had lymph node metastases. Skp2 was slightly correlated with Slug and AR in the whole cohort (Rs 0.32 and 0.37, respectively), which was enhanced for both proteins in patients with high Gleason scores (Rs 0.56 and 0.53, respectively) and, in the case of Slug, also in patients with metastasis to lymph nodes (Rs 0.56). Coexpression of Skp2 and Slug was confirmed in prostate cancer tissues by multiplex immunohistochemistry and confocal microscopy. The same relationship between these two proteins was observed in three sets of prostate epithelial cell lines (PC3, DU145, and E2) and their mesenchymal counterparts. Chemical inhibition of Skp2, but not RNA interference, modestly decreased Slug protein in PC3 and its docetaxel-resistant subline PC3 DR12. Importantly, chemical inhibition of Skp2 by MLN4924 upregulated p27 and decreased Slug expression in PC3, PC3 DR12, and LAPC4 cells. Novel treatment strategies targeting Skp2 and Slug by the neddylation blockade may be promising in advanced prostate cancer, as recently documented for other aggressive solid tumors.

• Klíčová slova
• Skp2 (S-phase kinase-associated protein 2), Slug, immunohistochemistry, multiplex, neddylation, prostate cancer,
• MeSH
• androgenní receptory genetika   metabolismus   MeSH
• antitumorózní látky farmakologie   MeSH
• buňky PC-3 MeSH
• CD antigeny genetika   metabolismus   MeSH
• cyklopentany farmakologie   MeSH
• docetaxel farmakologie   MeSH
• epitelo-mezenchymální tranzice genetika   MeSH
• inhibitor p27 cyklin-dependentní kinasy genetika   metabolismus   MeSH
• kadheriny genetika   metabolismus   MeSH
• lidé MeSH
• lymfatické metastázy MeSH
• malá interferující RNA genetika   metabolismus   MeSH
• nádorové buněčné linie MeSH
• nádory prostaty genetika   metabolismus   patologie   MeSH
• posttranslační úpravy proteinů * MeSH
• prostata metabolismus   patologie   MeSH
• protein NEDD8 genetika   metabolismus   MeSH
• proteiny asociované s kinázou S-fáze antagonisté a inhibitory   genetika   metabolismus   MeSH
• pyrimidiny farmakologie   MeSH
• regulace genové exprese u nádorů MeSH
• rodina transkripčních faktorů Snail genetika   metabolismus   MeSH
• stupeň nádoru MeSH
• viabilita buněk účinky léků   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• androgenní receptory MeSH
• antitumorózní látky MeSH
• CD antigeny MeSH
• CDH1 protein, human MeSH Prohlížeč
• cyklopentany MeSH
• docetaxel MeSH
• inhibitor p27 cyklin-dependentní kinasy MeSH
• kadheriny MeSH
• malá interferující RNA MeSH
• NEDD8 protein, human MeSH Prohlížeč
• pevonedistat MeSH Prohlížeč
• protein NEDD8 MeSH
• proteiny asociované s kinázou S-fáze MeSH
• pyrimidiny MeSH
• rodina transkripčních faktorů Snail MeSH
• SKP2 protein, human MeSH Prohlížeč
• SNAI1 protein, human MeSH Prohlížeč