Breast cancer is the most frequently diagnosed cancer in women worldwide. Although dramatically increased survival rates of early diagnosed cases have been observed, late diagnosed patients and metastatic cancer may still be considered fatal. The present study's main focus was on cancer‐associated fibroblasts (CAFs) which is an active component of the tumor microenvironment (TME) regulating the breast cancer ecosystem. Transcriptomic profiling and analysis of CAFs isolated from breast cancer skin metastasis, cutaneous basal cell carcinoma, and squamous cell carcinoma unravelled major gene candidates such as IL6, VEGFA and MFGE8 that induced co‐expression of keratins‐8/‐14 in the EM‐G3 cell line derived from infiltrating ductal breast carcinoma. Western blot analysis of selected keratins (keratin‐8, ‐14, ‐18, ‐19) and epithelial‐mesenchymal transition‐associated markers (SLUG, SNAIL, ZEB1, E‐/N‐cadherin, vimentin) revealed specific responses pointing to certain heterogeneity of the studied CAF populations. Experimental in vitro treatment using neutralizing antibodies against IL-6, VEGF‐A and MFGE8 attenuated the modulatory effect of CAFs on EM‐G3 cells. The present study provided novel data in characterizing and understanding the interactions between CAFs and EM‐G3 cells in vitro. CAFs of different origins support the pro‐inflammatory microenvironment and influence the biology of breast cancer cells. This observation potentially holds significant interest for the development of novel, clinically relevant approaches targeting the TME in breast cancer. Furthermore, its implications extend beyond breast cancer and have the potential to impact a wide range of other cancer types.
- MeSH
- antigeny povrchové MeSH
- fibroblasty asociované s nádorem * metabolismus MeSH
- fibroblasty metabolismus MeSH
- keratiny genetika metabolismus MeSH
- lidé MeSH
- maligní melanom kůže MeSH
- MFC-7 buňky MeSH
- mléčné bílkoviny genetika metabolismus MeSH
- nádorové buněčné linie MeSH
- nádorové mikroprostředí genetika MeSH
- nádory prsu * farmakoterapie genetika metabolismus MeSH
- prognóza MeSH
- transkriptom MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Kit ligand (Kitlg) is pleiotropic cytokine with a prominent role in vertebrate erythropoiesis. Although the role of Kitlg in this process has not been reported in Danio rerio (zebrafish), in the present study we show that its function is evolutionarily conserved. Zebrafish possess 2 copies of Kitlg genes (Kitlga and Kitlgb) as a result of whole-genome duplication. To determine the role of each ligand in zebrafish, we performed a series of ex vivo and in vivo gain- and loss-of-function experiments. First, we tested the biological activity of recombinant Kitlg proteins in suspension culture from zebrafish whole-kidney marrow, and we demonstrate that Kitlga is necessary for expansion of erythroid progenitors ex vivo. To further address the role of kitlga and kitlgb in hematopoietic development in vivo, we performed gain-of-function experiments in zebrafish embryos, showing that both ligands cooperate with erythropoietin (Epo) to promote erythroid cell expansion. Finally, using the kita mutant (kitab5/b5 or sparse), we show that the Kita receptor is crucial for Kitlga/b cooperation with Epo in erythroid cells. In summary, using optimized suspension culture conditions with recombinant cytokines (Epo, Kitlga), we report, for the first time, ex vivo suspension cultures of zebrafish hematopoietic progenitor cells that can serve as an indispensable tool to study normal and aberrant hematopoiesis in zebrafish. Furthermore, we conclude that, although partial functional diversification of Kit ligands has been described in other processes, in erythroid development, both paralogs play a similar role, and their function is evolutionarily conserved.
