Cannabinoids, a class of compounds derived from Cannabis sativa L., have recently become more widely accessible for public consumption in the form of diverse cannabis products, in parallel with weakening the measures that so far restricted their availability. The US Food and Drug Administration has approved several cannabis-derived drugs for management of various diseases as well as chemotherapy-induced nausea and vomiting. Besides the attenuation of adverse effects of chemotherapy, numerous reports about cannabinoid-mediated anticancer effects further motivate cancer patients to support their therapy with such products. Here we present a set of preclinical data with human cell culture models, suggesting that cannabidiol and cannabis extracts may effectively counteract the anticancer effects of the clinically widely used standard-of-care platinum-based drugs. We show that even low concentrations of cannabinoids reduced the toxicity of cisplatin, oxaliplatin, and carboplatin, an effect which was accompanied by decreased platinum adduct formation and a set of commonly used molecular markers. Mechanistically, our results excluded the possibility that the observed enhanced survival of cancer cells was mediated transcriptionally. Instead, trace metal analyses strongly indicate an inhibitory impact of cannabinoids on intracellular platinum accumulation, thereby implicating changes in cellular transport and/or retention of these drugs as the likely cause of the observed biological effects. Our study raises the possibility that the desirable effect of counteracting adverse effects of chemotherapy might, at least for some cannabinoids, reflect impaired cellular availability, and consequently attenuation of the anticancer effects of platinum drugs. DATA AVAILABILITY: All data supporting the conclusions are available in the article and supplementary files. Raw data are available upon request from the corresponding author.
Cannabidiol (CBD) is an easily accessible and affordable Marijuana (Cannabis sativa L.) plant derivative with an extensive history of medical use spanning thousands of years. Interest in the therapeutic potential of CBD has increased in recent years, including its anti-tumour properties in various cancer models. In addition to the direct anticancer effects of CBD, preclinical research on numerous cannabinoids, including CBD, has highlighted their potential use in: (i) attenuating chemotherapy-induced adverse effects and (ii) enhancing the efficacy of some anticancer drugs. Therefore, CBD is gaining popularity as a supportive therapy during cancer treatment, often in combination with standard-of-care cancer chemotherapeutics. However, CBD is a biologically active substance that modulates various cellular targets, thereby possibly resulting in unpredictable outcomes, especially in combinations with other medications and therapeutic modalities. In this review, we summarize the current knowledge of CBD interactions with selected anticancer chemotherapeutics, discuss the emerging mechanistic basis for the observed biological effects, and highlight both the potential benefits and risks of such combined treatments. Apart from the experimental and preclinical results, we also indicate the planned or ongoing clinical trials aiming to evaluate the impact of CBD combinations in oncology. The results of these and future trials are essential to provide better guidance for oncologists to judge the benefit-versus-risk ratio of these exciting treatment strategies. We hope that our present overview of this rapidly advancing field of biomedicine will inspire more preclinical and clinical studies to further our understanding of the underlying biology and optimize the benefits for cancer patients.
- MeSH
- Cannabis * MeSH
- kanabidiol * farmakologie terapeutické užití MeSH
- kanabinoidy * terapeutické užití MeSH
- lékové interakce MeSH
- lidé MeSH
- nádory * farmakoterapie MeSH
- protinádorové látky * farmakologie terapeutické užití MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Disulfiram (DSF), an established alcohol-aversion drug, is a candidate for repurposing in cancer treatment. DSF's antitumor activity is supported by preclinical studies, case reports, and small clinical trials; however, ongoing clinical trials of advanced-stage cancer patients encounter variable results. Here, we show that one reason for the inconsistent clinical effects of DSF may reflect interference by other drugs. Using a high-throughput screening and automated microscopy, we identify cannabidiol, an abundant component of the marijuana plant used by cancer patients to mitigate side effects of chemotherapy, as a likely cause of resistance to DSF. Mechanistically, in cancer cells, cannabidiol triggers the expression of metallothioneins providing protective effects by binding heavy metal-based substances including the bis-diethyldithiocarbamate-copper complex (CuET). CuET is the documented anticancer metabolite of DSF, and we show here that the CuET's anticancer toxicity is effectively neutralized by metallothioneins. Overall, this work highlights an example of undesirable interference between cancer therapy and the concomitant usage of marijuana products. In contrast, we report that insufficiency of metallothioneins sensitizes cancer cells toward CuET, suggesting a potential predictive biomarker for DSF repurposing in oncology.
Ribosome biogenesis is an essential, energy demanding process whose deregulation has been implicated in cancer, aging, and neurodegeneration. Ribosome biogenesis is therefore under surveillance of pathways including the p53 tumor suppressor. Here, we first performed a high-content siRNA-based screen of 175 human ribosome biogenesis factors, searching for impact on p53. Knock-down of 4 and 35 of these proteins in U2OS cells reduced and increased p53 abundance, respectively, including p53 accumulation after depletion of BYSL, DDX56, and WDR75, the effects of which were validated in several models. Using complementary approaches including subcellular fractionation, we demonstrate that endogenous human WDR75 is a nucleolar protein and immunofluorescence analysis of ectopic GFP-tagged WDR75 shows relocation to nucleolar caps under chemically induced nucleolar stress, along with several canonical nucleolar proteins. Mechanistically, we show that WDR75 is required for pre-rRNA transcription, through supporting the maintenance of physiological levels of RPA194, a key subunit of the RNA polymerase I. Furthermore, WDR75 depletion activated the RPL5/RPL11-dependent p53 stabilization checkpoint, ultimately leading to impaired proliferation and cellular senescence. These findings reveal a crucial positive role of WDR75 in ribosome biogenesis and provide a resource of human ribosomal factors the malfunction of which affects p53.
- MeSH
- buněčné jadérko genetika metabolismus MeSH
- DEAD-box RNA-helikasy metabolismus MeSH
- jaderné proteiny genetika metabolismus MeSH
- lidé MeSH
- molekuly buněčné adheze metabolismus MeSH
- nádorové buněčné linie MeSH
- nádorový supresorový protein p53 genetika metabolismus MeSH
- prekurzory RNA metabolismus MeSH
- ribozomální proteiny * genetika metabolismus MeSH
- ribozomy genetika metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Despite several approved therapeutic modalities, multiple myeloma (MM) remains an incurable blood malignancy and only a small fraction of patients achieves prolonged disease control. The common anti-MM treatment targets proteasome with specific inhibitors (PI). The resulting interference with protein degradation is particularly toxic to MM cells as they typically accumulate large amounts of toxic proteins. However, MM cells often acquire resistance to PIs through aberrant expression or mutations of proteasome subunits such as PSMB5, resulting in disease recurrence and further treatment failure. Here we propose CuET-a proteasome-like inhibitor agent that is spontaneously formed in-vivo and in-vitro from the approved alcohol-abuse drug disulfiram (DSF), as a readily available treatment effective against diverse resistant forms of MM. We show that CuET efficiently kills also resistant MM cells adapted to proliferate under exposure to common anti-myeloma drugs such as bortezomib and carfilzomib used as the first-line therapy, as well as to other experimental drugs targeting protein degradation upstream of the proteasome. Furthermore, CuET can overcome also the adaptation mechanism based on reduced proteasome load, another clinically relevant form of treatment resistance. Data obtained from experimental treatment-resistant cellular models of human MM are further corroborated using rather unique advanced cytotoxicity experiments on myeloma and normal blood cells obtained from fresh patient biopsies including newly diagnosed as well as relapsed and treatment-resistant MM. Overall our findings suggest that disulfiram repurposing particularly if combined with copper supplementation may offer a promising and readily available treatment option for patients suffering from relapsed and/or therapy-resistant multiple myeloma.
- MeSH
- bortezomib farmakologie terapeutické užití MeSH
- chemorezistence MeSH
- disulfiram farmakologie MeSH
- inhibitory proteasomu farmakologie terapeutické užití MeSH
- lidé MeSH
- lokální recidiva nádoru farmakoterapie MeSH
- mnohočetný myelom * patologie MeSH
- nádorové buněčné linie MeSH
- přehodnocení terapeutických indikací léčivého přípravku MeSH
- proteasomový endopeptidasový komplex metabolismus MeSH
- protinádorové látky * farmakologie terapeutické užití MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Despite proteotoxic stress and heat shock being implicated in diverse pathologies, currently no methodology to inflict defined, subcellular thermal damage exists. Here, we present such a single-cell method compatible with laser-scanning microscopes, adopting the plasmon resonance principle. Dose-defined heat causes protein damage in subcellular compartments, rapid heat-shock chaperone recruitment, and ensuing engagement of the ubiquitin-proteasome system, providing unprecedented insights into the spatiotemporal response to thermal damage relevant for degenerative diseases, with broad applicability in biomedicine. Using this versatile method, we discover that HSP70 chaperone and its interactors are recruited to sites of thermally damaged proteins within seconds, and we report here mechanistically important determinants of such HSP70 recruitment. Finally, we demonstrate a so-far unsuspected involvement of p97(VCP) translocase in the processing of heat-damaged proteins. Overall, we report an approach to inflict targeted thermal protein damage and its application to elucidate cellular stress-response pathways that are emerging as promising therapeutic targets.
- MeSH
- analýza jednotlivých buněk metody MeSH
- kovové nanočástice chemie MeSH
- lidé MeSH
- nádorové buněčné linie MeSH
- povrchová plasmonová rezonance MeSH
- proteasomový endopeptidasový komplex metabolismus MeSH
- protein obsahující valosin genetika metabolismus MeSH
- proteiny tepelného šoku HSP70 metabolismus MeSH
- reakce na tepelný šok * MeSH
- stříbro chemie MeSH
- ubikvitin metabolismus MeSH
- vysoká teplota škodlivé účinky MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
INTRODUCTION: The success of pregnancy depends on the regulation of immunological processes in the placenta. Important mediators of an immune response include pro- and anti-inflammatory interleukins which may be regulated by CYP epoxygenases and their metabolites. The relation between interleukins and CYP epoxygenases expression in human placenta has not yet been studied vastly. MATERIAL AND METHODS: We investigated the expression patterns of IL-1β and IL-10 in embryonic (n=8), early foetal (n=16) and term (n=7) human placenta tissue by an immunohistochemical method and evaluated the results by Kruskal-Wallis test. The obtained data was correlated using Spearman's correlation coefficient to our previously published data of CYP epoxygenases expression in the same samples. To confirm that Hofbauer cells express IL-10 and IL-1β as well as CYP2C8 and IL-10 together, and thus there is a relation between proteins of interests, we used multiplex immunofluorescent staining. RESULTS: The expression of IL-1β decreased with gestational age in cytotrophoblast, syncytiotrophoblast, as well as in Hofbauer cells whilst IL-10 decreased in cytotrophoblast, remained at the same levels in syncytiotrophoblast and increased in Hofbauer cells. In trophoblast cells, we found a statistically significant positive correlation between the expression of CYP2J2 and CYP2C9 with IL-1β, whereas there was no relation between IL-10 and any of the tested CYP epoxygenases. In Hofbauer cells, we found a significant positive correlation between CYP2C8 and IL-10 and a significant negative correlation between CYP2C8 and IL-1β. CONCLUSION: Our results showed that the exact role and relation of interleukins and CYP epoxygenases and their metabolites is dependent on their respective cellular context. Because of IL-10, IL-1β, as well as HBCs play a role in various pathological conditions, further investigation of the exact role of CYP epoxygenase, interleukins and their relations is needed.
- MeSH
- cytochrom P450 CYP2C8 MeSH
- interleukin-1 MeSH
- interleukin-10 * MeSH
- lidé MeSH
- placenta * MeSH
- těhotenství MeSH
- trofoblasty MeSH
- Check Tag
- lidé MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Research on repurposing the old alcohol-aversion drug disulfiram (DSF) for cancer treatment has identified inhibition of NPL4, an adaptor of the p97/VCP segregase essential for turnover of proteins involved in multiple pathways, as an unsuspected cancer cell vulnerability. While we reported that NPL4 is targeted by the anticancer metabolite of DSF, the bis-diethyldithiocarbamate-copper complex (CuET), the exact, apparently multifaceted mechanism(s) through which the CuET-induced aggregation of NPL4 kills cancer cells remains to be fully elucidated. Given the pronounced sensitivity to CuET in tumor cell lines lacking the genome integrity caretaker proteins BRCA1 and BRCA2, here we investigated the impact of NPL4 targeting by CuET on DNA replication dynamics and DNA damage response pathways in human cancer cell models. Our results show that CuET treatment interferes with DNA replication, slows down replication fork progression and causes accumulation of single-stranded DNA (ssDNA). Such a replication stress (RS) scenario is associated with DNA damage, preferentially in the S phase, and activates the homologous recombination (HR) DNA repair pathway. At the same time, we find that cellular responses to the CuET-triggered RS are seriously impaired due to concomitant malfunction of the ATRIP-ATR-CHK1 signaling pathway that reflects an unorthodox checkpoint silencing mode through ATR (Ataxia telangiectasia and Rad3 related) kinase sequestration within the CuET-evoked NPL4 protein aggregates.
- MeSH
- adaptorové proteiny signální transdukční metabolismus MeSH
- ATM protein antagonisté a inhibitory metabolismus MeSH
- checkpoint kinasa 1 metabolismus MeSH
- disulfiram farmakologie MeSH
- DNA vazebné proteiny metabolismus MeSH
- jaderné proteiny antagonisté a inhibitory metabolismus MeSH
- lidé MeSH
- nádorové buněčné linie MeSH
- nádory metabolismus patologie MeSH
- odvykací prostředky alkoholu farmakologie MeSH
- patologická konformace proteinů chemicky indukované MeSH
- poškození DNA účinky léků MeSH
- protein obsahující valosin metabolismus MeSH
- proteinové agregáty účinky léků MeSH
- replikace DNA účinky léků MeSH
- signální transdukce účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
DNA double-strand breaks (DSBs) signaling and repair is crucial to preserve genomic integrity and maintain cellular homeostasis. During the response to DSBs, histone ubiquitylation by RNF168 is a critical event, which or-chestrates the recruitment of downstream effectors, e.g. BRCA1 and 53BP1. While 53BP1 licenses the non-homologous end joining (NHEJ), BRCA1 initiates the DNA resection thus enabling homologous recombination (HR). Under conditions of ubiquitin starvation, mostly resulting from proteotoxic stress, the ubiquitin-dependent accumulation of DNA damage response proteins at the sites of DNA damage is impaired. Therefore, the proteo-toxic stress is commonly manifested by an attenuation of ubiquitin-mediated DSBs response. However, we have identified several cancer cell lines that display recruitment of 53BP1 to the sites of DSBs under the conditions of pro-teasome inhibitor (Bortezomib or MG132) induced proteo-toxic stress, i.e., under substantial depletion of nuclear free ubiquitin levels. This review brings a brief description of two major DSBs repair pathways: HR and NHEJ, their functional dependency on signaling through ubiquitin and a discussion of newly identified phenomenon of proteo-toxic stress resistant response to DNA double-strand breaks.
DNA replication is a highly demanding process regarding the energy and material supply and must be precisely regulated, involving multiple cellular feedbacks. The slowing down or stalling of DNA synthesis and/or replication forks is referred to as replication stress (RS). Owing to the complexity and requirements of replication, a plethora of factors may interfere and challenge the genome stability, cell survival or affect the whole organism. This review outlines chemical compounds that are known inducers of RS and commonly used in laboratory research. These compounds act on replication by direct interaction with DNA causing DNA crosslinks and bulky lesions (cisplatin), chemical interference with the metabolism of deoxyribonucleotide triphosphates (hydroxyurea), direct inhibition of the activity of replicative DNA polymerases (aphidicolin) and interference with enzymes dealing with topological DNA stress (camptothecin, etoposide). As a variety of mechanisms can induce RS, the responses of mammalian cells also vary. Here, we review the activity and mechanism of action of these compounds based on recent knowledge, accompanied by examples of induced phenotypes, cellular readouts and commonly used doses.
- MeSH
- buňky účinky léků metabolismus MeSH
- fyziologický stres * účinky léků MeSH
- lidé MeSH
- protinádorové látky chemie farmakologie MeSH
- replikace DNA * účinky léků MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
