Latest Publications

@article{prochazkova_single-cell_2024,

title = {Single-cell profiling of surface glycosphingolipids opens a new dimension for deconvolution of breast cancer intratumoral heterogeneity and phenotypic plasticity.},

author = {Jiřina Procházková and Radek Fedr and Barbora Hradilová and Barbora Kvokačková and Josef Slavík and Ondrej Kováč and Miroslav Machala and Pavel Fabian and Jiří Navrátil and Simona Kráčalíková and Monika Levková and Petra Ovesná and Jan Bouchal and Karel Souček},

doi = {10.1016/j.jlr.2024.100609},

issn = {1539-7262 0022-2275},

year  = {2024},

date = {2024-09-01},

journal = {Journal of lipid research},

volume = {65},

number = {9},

pages = {100609},

abstract = {Glycosylated sphingolipids (GSLs) are a diverse group of cellular lipids typically reported as being rare in normal mammary tissue. In breast cancer (BCa), GSLs have emerged as noteworthy markers associated with breast cancer stem cells, mediators of phenotypic plasticity, and contributors to cancer cell chemoresistance. GSLs are potential surface markers that can uniquely characterize the heterogeneity of the tumor microenvironment, including cancer cell subpopulations and epithelial-mesenchymal plasticity (EMP). In this study, mass spectrometry analyses of the total sphingolipidome in breast epithelial cells and their mesenchymal counterparts revealed increased levels of Gb3 in epithelial cells and significantly elevated GD2 levels in the mesenchymal phenotype. To elucidate if GSL-related epitopes on BCa cell surfaces reflect EMP and cancer status, we developed and rigorously validated a 12-color spectral flow cytometry panel. This panel enables the simultaneous detection of native GSL epitopes (Gb3, SSEA1, SSEA3, SSEA4, and GD2), epithelial-mesenchymal transition markers (EpCAM, TROP2, and CD9), and lineage markers (CD45, CD31, and CD90) at the single-cell level. Next, the established panel was used for the analysis of BCa primary tumors and revealed surface heterogeneity in SSEA1, SSEA3, SSEA4, GD2, and Gb3, indicative of native epitope presence also on non-tumor cells. These findings further highlighted the phenotype-dependent alterations in GSL surface profiles, with differences between epithelial and stromal cells in the tumor. This study provides novel insights into BCa heterogeneity, shedding light on the potential of native GSL-related epitopes as markers for EMP and cancer status in fresh clinical samples. The developed single-cell approach offers promising avenues for further exploration.},

note = {Place: United States},

keywords = {*Breast Neoplasms/metabolism/pathology, *Epithelial-Mesenchymal Transition, *Glycosphingolipids/metabolism/analysis, *Single-Cell Analysis/methods, Breast cancer, Epithelial Cells, Female, Glycosphingolipids, Humans, Phenotype, phenotypic plasticity, stromal-like cells, surface profiling},

pubstate = {published},

tppubtype = {article}

}

@article{hofmanova_complex_2021,

title = {Complex Alterations of Fatty Acid Metabolism and Phospholipidome Uncovered in Isolated Colon Cancer Epithelial Cells.},

author = {Jiřina Hofmanová and Josef Slavík and Miroslav Ciganek and Petra Ovesná and Zuzana Tylichová and Martina Karasová and Ondřej Zapletal and Nicol Straková and Jiřina Procházková and Jan Bouchal and Zdeněk Kolář and Jiří Ehrmann and Monika Levková and Zlatka Hušková and Pavel Skalický and Alois Kozubík and Miroslav Machala and Jan Vondráček},

doi = {10.3390/ijms22136650},

issn = {1422-0067},

year  = {2021},

date = {2021-06-01},

journal = {International journal of molecular sciences},

volume = {22},

number = {13},

abstract = {The development of colon cancer, one of the most common malignancies, is accompanied with numerous lipid alterations. However, analyses of whole tumor samples may not always provide an accurate description of specific changes occurring directly in tumor epithelial cells. Here, we analyzed in detail the phospholipid (PL), lysophospholipid (lysoPL), and fatty acid (FA) profiles of purified EpCAM(+) cells, isolated from tumor and adjacent non-tumor tissues of colon cancer patients. We found that a number of FAs increased significantly in isolated tumor cells, which also included a number of long polyunsaturated FAs. Higher levels of FAs were associated with increased expression of FA synthesis genes, as well as with altered expression of enzymes involved in FA elongation and desaturation, including particularly fatty acid synthase, stearoyl-CoA desaturase, fatty acid desaturase 2 and ELOVL5 fatty acid elongase 5 We identified significant changes in ratios of specific lysoPLs and corresponding PLs. A number of lysophosphatidylcholine and lysophosphatidylethanolamine species, containing long-chain and very-long chain FAs, often with high numbers of double bonds, were significantly upregulated in tumor cells. Increased de novo synthesis of very long-chain FAs, or, altered uptake or incorporation of these FAs into specific lysoPLs in tumor cells, may thus contribute to reprogramming of cellular phospholipidome and membrane alterations observed in colon cancer.},

note = {Place: Switzerland},

keywords = {*Gene Expression Regulation, *Lipid Metabolism, Adenocarcinoma/enzymology/genetics/*metabolism, Aged, Colonic Neoplasms/enzymology/genetics/*metabolism, colorectal carcinoma, desaturation, EpCAM, Epithelial Cells, Epithelial Cells/enzymology/metabolism, Fatty Acid Desaturases/genetics/metabolism, Fatty Acid Elongases/genetics/metabolism, Fatty Acid Synthases/genetics/metabolism, fatty acid synthesis, Fatty Acids/*metabolism, Female, Humans, lipidomics, Lipogenesis, lysophospholipids, Male, Neoplastic, Phospholipids, Phospholipids/*metabolism, Stearoyl-CoA Desaturase/genetics/metabolism},

pubstate = {published},

tppubtype = {article}

}

@article{hyzdalova_prolonged_2021,

title = {A prolonged exposure of human lung carcinoma epithelial cells to benzo[a]pyrene induces p21-dependent epithelial-to-mesenchymal transition (EMT)-like phenotype.},

author = {Martina Hýžďalová and Jiřina Procházková and Simona Strapáčová and Lucie Svržková and Ondřej Vacek and Radek Fedr and Zdeněk Andrysík and Eva Hrubá and Helena Líbalová and Jiří Kléma and Jan Topinka and Josef Mašek and Karel Souček and Jan Vondráček and Miroslav Machala},

doi = {10.1016/j.chemosphere.2020.128126},

issn = {1879-1298 0045-6535},

year  = {2021},

date = {2021-01-01},

journal = {Chemosphere},

volume = {263},

pages = {128126},

abstract = {Deciphering the role of the aryl hydrocarbon receptor (AhR) in lung cancer cells may help us to better understand the role of toxic AhR ligands in lung carcinogenesis, including cancer progression. We employed human lung carcinoma A549 cells to investigate their fate after continuous two-week exposure to model AhR agonists, genotoxic benzo[a]pyrene (BaP; 1 μM) and non-genotoxic 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD; 10 nM). While TCDD increased proliferative rate of A549 cells, exposure to BaP decreased cell proliferation and induced epithelial-to-mesenchymal transition (EMT)-like phenotype, which was associated with enhanced cell migration, invasion, and altered cell morphology. Although TCDD also suppressed expression of E-cadherin and activated some genes linked to EMT, it did not induce the EMT-like phenotype. The results of transcriptomic analysis, and the opposite effects of BaP and TCDD on cell proliferation, indicated that a delay in cell cycle progression, together with a slight increase of senescence (when coupled with AhR activation), favors the induction of EMT-like phenotype. The shift towards EMT-like phenotype observed after simultaneous treatment with TCDD and mitomycin C (an inhibitor of cell proliferation) confirmed the hypothesis. Since BaP decreased cell proliferative rate via induction of p21 expression, we generated the A549 cell model with reduced p21 expression and exposed it to BaP for two weeks. The p21 knockdown suppressed the BaP-mediated EMT-like phenotype in A549 cells, thus confirming that a delayed cell cycle progression, together with p21-dependent induction of senescence-related chemokine CCL2, may contribute to induction of EMT-like cell phenotype in lung cells exposed to genotoxic AhR ligands.},

note = {Place: England},

keywords = {*Carcinoma, *Lung Neoplasms/genetics, Aryl Hydrocarbon/genetics, BaP, Benzo(a)pyrene/toxicity, Cell Proliferation, EMT, Epithelial Cells, Humans, Lung, Lung carcinoma, Phenotype, Receptors, TCDD, Tumor progression},

pubstate = {published},

tppubtype = {article}

}

@article{kahounova_slug-expressing_2020,

title = {Slug-expressing mouse prostate epithelial cells have increased stem cell potential.},

author = {Zuzana Kahounová and Ján Remšík and Radek Fedr and Jan Bouchal and Alena Mičková and Eva Slabáková and Lucia Binó and Aleš Hampl and Karel Souček},

doi = {10.1016/j.scr.2020.101844},

issn = {1876-7753 1873-5061},

year  = {2020},

date = {2020-07-01},

journal = {Stem cell research},

volume = {46},

pages = {101844},

abstract = {Deciphering the properties of adult stem cells is crucial for understanding of their role in healthy tissue and in cancer progression as well. Both stem cells and cancer stem cells have shown association with epithelial-to-mesenchymal transition (EMT) in various tissue types. Aiming to investigate the epithelial and mesenchymal phenotypic traits in adult mouse prostate, we sorted subpopulations of basal prostate stem cells (mPSCs) and assessed the expression levels of EMT regulators and markers with custom-designed gene expression array. The population of mPSCs defined by a Lin(-)/Sca-1(+)CD49f(hi)/Trop-2(+) (LSC Trop-2(+)) surface phenotype was enriched in mesenchymal markers, especially EMT master regulator Slug, encoded by the Snai2 gene. To further dissect the role of Slug in mPSCs, we used transgenic Snai2(tm1.1Wbg) reporter mouse strain. Using this model, we confirmed the presence of mesenchymal traits and increase of organoid forming capacity in Slug(+) population of mPSCs. The Slug(+)-derived organoids comprised all prostate epithelial cell types - basal, luminal, and neuroendocrine. Collectively, these data uncover the important role of Slug expression in the physiology of mouse prostate stem cells.},

note = {Place: England},

keywords = {*Epithelial-Mesenchymal Transition, *Prostate, Animals, Cell Line, Cell Movement, Epithelial Cells, epithelial-to-mesenchymal transition, Male, Mice, Organoids, Prostate stem cells, Snai2/Slug, Snail Family Transcription Factors/genetics, stemness, Tumor},

pubstate = {published},

tppubtype = {article}

}