Publications by authors named "Jan Brabek"

Protein synthesis plays a major role in homeostasis and when dysregulated leads to various pathologies including cancer. To this end, imbalanced expression of eukaryotic translation initiation factors (eIFs) is not only a consequence but also a driver of neoplastic growth. eIF3 is the largest, multi-subunit translation initiation complex with a modular assembly, where aberrant expression of one subunit generates only partially functional subcomplexes.

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Glioblastomas are aggressive brain tumors for which effective therapy is still lacking, resulting in dismal survival rates. These tumors display significant phenotypic plasticity, harboring diverse cell populations ranging from tumor core cells to dispersed, highly invasive cells. Neuron navigator 3 (NAV3), a microtubule-associated protein affecting microtubule growth and dynamics, is downregulated in various cancers, including glioblastoma, and has thus been considered a tumor suppressor.

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Multiple studies indicate that iron chelators enhance their anti-cancer properties by inducing NDRG1, a known tumor and metastasis suppressor. However, the exact role of NDRG1 remains controversial, as newer studies have shown that NDRG1 can also act as an oncogene. Our group recently introduced mitochondrially targeted iron chelators deferoxamine (mitoDFO) and deferasirox (mitoDFX) as effective anti-cancer agents.

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Traditionally, anticancer therapies focus on restraining uncontrolled proliferation. However, these cytotoxic therapies expose cancer cells to direct killing, instigating the process of natural selection favoring survival of resistant cells that become the foundation for tumor progression and therapy failure. Recognizing this phenomenon has prompted the development of alternative therapeutic strategies.

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Cancer is still one of the leading causes of death, with an estimated 19.3 million new cases every year. Our paper presents the tumor-suppressing effect of and on B16F10 melanoma, the intraperitoneal application of which followed the experimental infection with these tapeworms, resulting in varying degrees of effectiveness in two strains of mice.

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Background: Amplification of HER2, a receptor tyrosine kinase and a breast cancer-linked oncogene, is associated with aggressive disease. HER2 protein is localised mostly at the cell membrane, but a fraction translocates to mitochondria. Whether and how mitochondrial HER2 contributes to tumorigenicity is currently unknown.

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Cytochalasans are known as inhibitors of actin polymerization and for their cytotoxic and migrastatic activity. In this study, we synthesized a series of cytochalasin derivatives that lack a macrocyclic moiety, a structural element traditionally considered essential for their biological activity. We focused on substituting the macrocycle with simple aryl-containing sidechains, and we have also synthesized compounds with different substitution patterns on the cytochalasin core.

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The activation of Src kinase in cells is strictly controlled by intramolecular inhibitory interactions mediated by SH3 and SH2 domains. They impose structural constraints on the kinase domain holding it in a catalytically non-permissive state. The transition between inactive and active conformation is known to be largely regulated by the phosphorylation state of key tyrosines 416 and 527.

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Solid tumor metastases cause most cancer-related deaths. The prevention of their occurrence misses suitable anti-metastases medicines newly labeled as migrastatics. The first indication of migrastatics potential is based on an inhibition of enhanced migration of tumor cell lines.

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MT1-MMP (MMP-14) is a multifunctional protease that regulates ECM degradation, activation of other proteases, and a variety of cellular processes, including migration and viability in physiological and pathological contexts. Both the localization and signal transduction capabilities of MT1-MMP are dependent on its cytoplasmic domain that constitutes the final 20 C-terminal amino acids, while the rest of the protease is extracellular. In this review, we summarize the ways in which the cytoplasmic tail is involved in regulating and enacting the functions of MT1-MMP.

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The ability of cells to switch between different invasive modes during metastasis, also known as invasion plasticity, is an important characteristic of tumor cells that makes them able to resist treatment targeted to a particular invasion mode. Due to the rapid changes in cell morphology during the transition between mesenchymal and amoeboid invasion, it is evident that this process requires remodeling of the cytoskeleton. Although the role of the actin cytoskeleton in cell invasion and plasticity is already quite well described, the contribution of microtubules is not yet fully clarified.

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Most cancer-related deaths among patients with solid tumors are caused by metastases. Migrastatic strategies represent a unique therapeutic approach to prevent all forms of cancer cell migration and invasion. Because the migration machinery has been shown to promote metastatic dissemination, successful migrastatic therapy may reduce the need for high-dose cytotoxic therapies that are currently used to prevent the risk of metastatic dissemination.

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Interleukin 6 (IL-6) belongs to a broad class of cytokines involved in the regulation of various homeostatic and pathological processes. These activities range from regulating embryonic development, wound healing and ageing, inflammation, and immunity, including COVID-19. In this review, we summarise the role of IL-6 signalling pathways in cancer biology, with particular emphasis on cancer cell invasiveness and metastasis formation.

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Mitochondria generate energy and building blocks required for cellular growth and function. The notion that mitochondria are not involved in the cancer growth has been challenged in recent years together with the emerging idea of mitochondria as a promising therapeutic target for oncologic diseases. Pentamethinium salts, cyan dyes with positively charged nitrogen on the benzothiazole or indole part of the molecule, were originally designed as mitochondrial probes.

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Recent evidence indicates that targeting IL-6 provides broad therapeutic approaches to several diseases. In patients with cancer, autoimmune diseases, severe respiratory infections [e.g.

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Cancer-associated fibroblasts (CAFs) are an essential component of the tumour microenvironment. They represent a heterogeneous group of cells that are under the control of cancer cells and can reversely influence the cancer cell population. They affect the cancer cell differentiation status, and the migration and formation of metastases.

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The incidence of cutaneous malignant melanoma is increasing worldwide. While the treatment of initial stages of the disease is simple, the advanced disease frequently remains fatal despite novel therapeutic options . This requires identification of novel therapeutic targets in melanoma.

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Metastasis accounts for the highest mortality rates in solid tumor cancer patients. However, research and development have neglected this most lethal characteristic and, instead, have concentrated on the hallmarks of cancer that make tumor cells highly proliferative and distinctive from nonmalignant cells. The concentration on invasion and metastasis can be one of the most meaningful advancements in cancer investigation.

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Hepatocellular carcinoma is a highly aggressive and difficult-to-treat type of cancer. Incorporating urea functionality into the backbone of organoselenium compounds is expected to develop promising chemotherapeutic leads against liver cancer. Urea-functionalized organoselenium compounds were synthesized in good yields, and their cytotoxicity was evaluated against HepG2 cells.

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Cancer cell invasion through tissue barriers is the intrinsic feature of metastasis, the most life-threatening aspect of cancer. Detailed observation and analysis of cancer cell behaviour in a 3D environment is essential for a full understanding of the mechanisms of cancer cell invasion. The inherent limits of optical microscopy resolution do not allow to for in-depth observation of intracellular structures, such as invadopodia of invading cancer cells.

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Background: Uveal melanoma (UM) is the most common intraocular tumour in adults with a poor prognosis and extremely high mortality rate due to the development of metastatic disease. However, despite relatively good knowledge about the histological and genetic risk factors for metastasis development, there is no specific biomarker that would allow early detection of UM progression. Recently, exosomes and their molecular cargo have been widely studied in the search for potential biomarkers in several cancers.

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ARHGAP42 encodes Rho GTPase activating protein 42 that belongs to a member of the GTPase Regulator Associated with Focal Adhesion Kinase (GRAF) family. ARHGAP42 is involved in blood pressure control by regulating vascular tone. Despite these findings, disorders of human variants in the coding part of ARHGAP42 have not been reported.

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COVID-19 is a pandemic respiratory disease caused by the SARS-CoV-2 coronavirus. The worldwide epidemiologic data showed higher mortality in males compared to females, suggesting a hypothesis about the protective effect of estrogens against severe disease progression with the ultimate end being patient's death. This article summarizes the current knowledge regarding the potential effect of estrogens and other modulators of estrogen receptors on COVID-19.

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The tumorigenic potential of mouse polyomavirus (MPyV) has been studied for decades in cell culture models and has been mainly attributed to nonstructural middle T antigen (MT), which acts as a scaffold signal adaptor, activates Src tyrosine kinases, and possesses transforming ability. We hypothesized that MPyV could also transform mouse cells independent of MT via a Toll-like receptor 4 (TLR4)-mediated inflammatory mechanism. To this end, we investigated the interaction of MPyV with TLR4 in mouse embryonic fibroblasts (MEFs) and 3T6 cells, resulting in secretion of interleukin 6 (IL-6), independent of active viral replication.

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