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G-quadruplex-guided cisplatin triggers multiple pathways in targeted chemotherapy and immunotherapy.Chemical Science Jun 2024G-quadruplexes (G4s) are atypical nucleic acid structures involved in basic human biological processes and are regulated by small molecules. To date, pyridostatin and...
G-quadruplexes (G4s) are atypical nucleic acid structures involved in basic human biological processes and are regulated by small molecules. To date, pyridostatin and its derivatives [, PyPDS (4-(2-aminoethoxy)- , -bis(4-(2-(pyrrolidin-1-yl) ethoxy) quinolin-2-yl) pyridine-2,6-dicarboxamide)] are the most widely used G4-binding small molecules and considered to have the best G4 specificity, which provides a new option for the development of cisplatin-binding DNA. By combining PyPDS with cisplatin and its analogs, we synthesize three platinum complexes, named PyPDSplatins. We found that cisplatin with PyPDS (CP) exhibits stronger specificity for covalent binding to G4 domains even in the presence of large amounts of dsDNA compared with PyPDS either extracellularly or intracellularly. Multiomics analysis reveals that CP can effectively regulate G4 functions, directly damage G4 structures, activate multiple antitumor signaling pathways, including the typical cGAS-STING pathway and AIM2-ASC pathway, trigger a strong immune response and lead to potent antitumor effects. These findings reflect that cisplatin-conjugated specific G4 targeting groups have antitumor mechanisms different from those of classic cisplatin and provide new strategies for the antitumor immunity of metals.
PubMed: 38939132
DOI: 10.1039/d4sc00643g -
JACS Au Jun 2024MeXpose is an end-to-end image analysis pipeline designed for mechanistic studies of metal exposure, providing spatial single-cell metallomics using laser...
MeXpose is an end-to-end image analysis pipeline designed for mechanistic studies of metal exposure, providing spatial single-cell metallomics using laser ablation-inductively coupled plasma time-of-flight mass spectrometry (LA-ICP-TOFMS). It leverages the high-resolution capabilities of low-dispersion laser ablation setups, a standardized approach to quantitative bioimaging, and the toolbox of immunohistochemistry using metal-labeled antibodies for cellular phenotyping. MeXpose uniquely unravels quantitative metal bioaccumulation (sub-fg range per cell) in phenotypically characterized tissue. Furthermore, the full scope of single-cell metallomics is offered through an extended mass range accessible by ICP-TOFMS instrumentation (covering isotopes from / 14-256). As a showcase, an human skin model exposed to cobalt chloride (CoCl) was investigated. For the first time, metal permeation was studied at single-cell resolution, showing high cobalt (Co) accumulation in the epidermis, particularly in mitotic basal cells, which correlated with DNA damage. Significant Co deposits were also observed in vascular cells, with notably lower levels in dermal fibers. MeXpose provides unprecedented insights into metal bioaccumulation with the ability to explore relationships between metal exposure and cellular responses on a single-cell level, paving the way for advanced toxicological and therapeutic studies.
PubMed: 38938797
DOI: 10.1021/jacsau.4c00154 -
Drug and Chemical Toxicology Jun 2024Acrylamide (ACR) can have adverse environmental effects because of its multiple applications. Relevant scientific literatures of the existence of ACR residues in foods...
Acrylamide (ACR) can have adverse environmental effects because of its multiple applications. Relevant scientific literatures of the existence of ACR residues in foods following processing steps have raised concern in the biochemistry, chemistry and safety of this vinyl substance. The interest has focused on the hepatotoxicity of ACR in animals and humans and on the ACR content mitigation and its detoxification. Borax (BX), as a naturally occurring antioxidant featured boron compound, was selected in this investigation to assess its possible neuro-protective potential against ACR-induced neurotoxicity. Nrf2 axis signaling pathways and detoxification response to oxidative stress after exposure to ACR in brains of rainbow trout, and the effect of BX application on reducing ACR-induced neurotoxicity were investigated. Rainbow trout were acutely exposed to ACR (12.5 mg/L) alone or simultaneously treated with BX (0.75 mg/L) during 96h. The exposed fish were sampled at 48th and 96th and oxidative stress response endpoints, 8-OHdG, Nrf2, TNF-α, caspase-3, in addition to IL-6 activities and the levels of AChE and BDNF in brain tissues of rainbow trout () were evaluated. Samples showed decreases in the levels of ACR-mediated biomarkers used to assess neural toxicity (SOD, CAT, GPx, AChE, BDNF, GSH), increased levels of MDA, MPO, DNA damage and apoptosis. ACR disrupted the Nrf2 pathway, and induced neurotoxicity. Inhibited activities' expressions under simultaneous administration experiments, revealed the protective effects of BX against ACR-induced toxicity damage. The obtained data allow the outline of early multi-parameter signaling pathways in rainbow trout.
PubMed: 38938109
DOI: 10.1080/01480545.2024.2370916 -
Pediatric Blood & Cancer Jun 2024Neuroblastoma (NB) is the most common solid tumour in childhood, and rises in the sympathetic nervous system. Here, we addressed the in silico analysis of the...
BACKGROUND
Neuroblastoma (NB) is the most common solid tumour in childhood, and rises in the sympathetic nervous system. Here, we addressed the in silico analysis of the association between the expression of H2AFX gene involved in DNA damage response, and the survival of a cohort of 786 NB patients.
METHODS
In silico gene expression was retrieved from the publicly available dataset summarised by Cangelosi et al., including 13,696 gene expression profiles of 786 NB tumours at onset of disease. The prognostic value of H2AFX (H2A histone family member X) gene expression for event-free survival (EFS) and overall survival (OS) was evaluated by Kaplan-Meier and Cox regression analysis. The main results were validated on another openly accessible in silico database (NRC-283) containing 13,489 gene expressions in 283 NB patients. The expression of H2AFX protein was then tested by immunofluorescence on 48 primary NB samples of different tumour stages. H2AFX activity as an oncogene has been further validated in vitro by silencing the molecule in two NB cell lines, characterised by MYCN amplified or not, and performing cell growth and migration assays.
RESULTS
A strong inverse association between H2AFX expression and patients' survival was observed and confirmed by immunofluorescence results on primary NB tissue sections. Cox regression analysis also disclosed H2AFX as an independent predictor of EFS and OS. The gene-silencing experiments strongly suggested an oncogenic role for H2AFX on NB cells, regardless of MYCN amplification.
CONCLUSIONS
H2AFX is a prognostic marker for unfavourable NB and could be considered a target for therapeutic interventions.
PubMed: 38938078
DOI: 10.1002/pbc.31146 -
International Journal of Cancer Jun 2024Prognosis of glioblastoma patients is still poor despite multimodal therapy. The highly brain-infiltrating growth in concert with a pronounced therapy resistance...
K channel targeting impairs DNA repair and invasiveness of patient-derived glioblastoma stem cells in culture and orthotopic mouse xenografts which only in part is predictable by K expression levels.
Prognosis of glioblastoma patients is still poor despite multimodal therapy. The highly brain-infiltrating growth in concert with a pronounced therapy resistance particularly of mesenchymal glioblastoma stem-like cells (GSCs) has been proposed to contribute to therapy failure. Recently, we have shown that a mesenchymal-to-proneural mRNA signature of patient derived GSC-enriched (pGSC) cultures associates with in vitro radioresistance and gel invasion. Importantly, this pGSC mRNA signature is prognostic for patients' tumor recurrence pattern and overall survival. Two mesenchymal markers of the mRNA signature encode for IK and BK Ca-activated K channels. Therefore, we analyzed here the effect of IK- and BK-targeting concomitant to (fractionated) irradiation on radioresistance and glioblastoma spreading in pGSC cultures and in pGSC-derived orthotopic xenograft glioma mouse models. To this end, in vitro gel invasion, clonogenic survival, in vitro and in vivo residual DNA double strand breaks (DSBs), tumor growth, and brain invasion were assessed in the dependence on tumor irradiation and K channel targeting. As a result, the IK- and BK-blocker TRAM-34 and paxilline, respectively, increased number of residual DSBs and (numerically) decreased clonogenic survival in some but not in all IK- and BK-expressing pGSC cultures, respectively. In addition, BK- but not IK-blockade slowed-down gel invasion in vitro. Moreover, systemic administration of TRAM-34 or paxilline concomitant to fractionated tumor irradiation increased in the xenograft model(s) residual number of DSBs and attenuated glioblastoma brain invasion and (numerically) tumor growth. We conclude, that K-blockade concomitant to fractionated radiotherapy might be a promising new strategy in glioblastoma therapy.
PubMed: 38938062
DOI: 10.1002/ijc.35064 -
Journal of Biophotonics Jun 2024Photobiomodulation (PBM) using 460 nm blue light has been shown to have an inhibitory effect on skin cancer cells. In this study, we used a continuous LED light source...
Photobiomodulation (PBM) using 460 nm blue light has been shown to have an inhibitory effect on skin cancer cells. In this study, we used a continuous LED light source with a wavelength of 460 nm and designed various combinations of power density (ranging from 6.4 to 25.6 mW) and dose (ranging from 0.96 to 30.72 J/cm) to conduct treatment experiments on MeWo cells to investigate the effects of blue light on MeWo melanoma cells. We are focusing on cell viability, cytotoxicity, mitochondrial function, oxidative stress, and apoptosis. We found that blue light inhibits these melanoma cells through oxidative stress and DNA damage, and this inhibition intensifies at higher irradiance levels. Although the cells initially attempt to resist the stress induced by the treatment, they eventually undergo apoptosis over time. These findings contribute to understanding melanoma's molecular response to blue light PBM, lay the groundwork for future clinical applications.
PubMed: 38937982
DOI: 10.1002/jbio.202400071 -
Journal of Biochemical and Molecular... Jul 2024Anticancer strategies using natural products or derivatives are promising alternatives for cancer treatment. Here, we showed that licochalcone D (LCD), a natural...
Licochalcone D exhibits cytotoxicity in breast cancer cells and enhances tumor necrosis factor-related apoptosis-inducing ligand-induced apoptosis through upregulation of death receptor 5.
Anticancer strategies using natural products or derivatives are promising alternatives for cancer treatment. Here, we showed that licochalcone D (LCD), a natural flavonoid extracted from Glycyrrhiza uralensis Fisch, suppressed the growth of breast cancer cells, and was less toxic to MCF-10A normal breast cells. LCD-induced DNA damage, cell cycle arrest, and apoptosis in breast cancer cells. Furthermore, LCD potentiated tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced cytotoxicity. Mechanistically, LCD was revealed to reduce survival protein expression and to upregulate death receptor 5 (DR5) expressions. Silencing DR5 blocked the ability of LCD to sensitize cells to TRAIL-mediated apoptosis. LCD increased CCAAT/enhancer-binding protein homologous protein (CHOP) expression in breast cancer cells. Knockdown of CHOP attenuated DR5 upregulation and apoptosis triggered by cotreatment with LCD and TRAIL. Furthermore, LCD suppressed the phosphorylation of extracellular signal-regulated kinase and promoted the phosphorylation of c-Jun amino-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK). Pretreatment with JNK inhibitor SP600125 or p38 MAPK inhibitor SB203580 abolished the upregulation of DR5 and CHOP, and also attenuated LCD plus TRAIL-induced cleavage of poly(ADP-ribose) polymerase. Overall, our results show that LCD exerts cytotoxic effects on breast cancer cells and arguments TRAIL-mediated apoptosis by inhibiting survival protein expression and upregulating DR5 in a JNK/p38 MAPK-CHOP-dependent manner.
Topics: Humans; Receptors, TNF-Related Apoptosis-Inducing Ligand; Chalcones; TNF-Related Apoptosis-Inducing Ligand; Breast Neoplasms; Apoptosis; Female; Up-Regulation; Transcription Factor CHOP; Cell Line, Tumor; Gene Expression Regulation, Neoplastic; MCF-7 Cells; MAP Kinase Signaling System
PubMed: 38937960
DOI: 10.1002/jbt.23757 -
Skin Research and Technology : Official... Jul 2024Patients with myotonic muscular dystrophy (MMD) were observed to have numerous basal cell carcinoma (BCC) and abnormal dysplastic nevi (DN) on non-sun exposed skin.... (Review)
Review
OBJECTIVE
Patients with myotonic muscular dystrophy (MMD) were observed to have numerous basal cell carcinoma (BCC) and abnormal dysplastic nevi (DN) on non-sun exposed skin. Simultaneously a large study published in the Journal of American Medical Association (JAMA) illustrated that patients with MMD have "overall" an increased risk for cancer development. Based on these findings, this author in 2010 postulated that dysregulation of RNA binding proteins (RBP), responsible for clinical manifestations of MMD, is also responsible for the development of BCC and melanoma.
METHODS
To report new research elucidating the etiology of melanoma, BCC, MMD-induced cancers, and potentially other environmentally induced malignancies.
RESULTS
Dysregulation of RBP induces aberrant mRNA splicing; recent data indicates that abnormal mRNA splicing not just plays a key role in the pathogenesis of melanoma but is a hallmark of essentially all human malignancies.
CONCLUSION
The author's hypothesis is that ultraviolet (UV) radiation induces DNA damage in intronic regions of a variety of genes. Furthermore, these UV-induced abnormal DNA dimers, repeats and mutations interfere with normal mRNA splicing thus producing abnormal proteins. These abnormal proteins in turn activate oncogenic pathways such as hedgehog, MAP kinase, and WNT.
Topics: Humans; Skin Neoplasms; Melanoma; Carcinoma, Basal Cell; Genetic Predisposition to Disease; Genetic Testing; Myotonic Dystrophy; Ultraviolet Rays
PubMed: 38937899
DOI: 10.1111/srt.13832 -
Scientific Reports Jun 2024Radiation delivery at ultrahigh dose rates (UHDRs) has potential for use as a new anticancer therapeutic strategy. The FLASH effect induced by UHDR irradiation has been...
Radiation delivery at ultrahigh dose rates (UHDRs) has potential for use as a new anticancer therapeutic strategy. The FLASH effect induced by UHDR irradiation has been shown to maintain antitumour efficacy with a reduction in normal tissue toxicity; however, the FLASH effect has been difficult to demonstrate in vitro. The objective to demonstrate the FLASH effect in vitro is challenging, aiming to reveal a differential response between cancer and normal cells to further identify cell molecular mechanisms. New high-intensity petawatt laser-driven accelerators can deliver very high-energy electrons (VHEEs) at dose rates as high as 10 Gy/s in very short pulses (10 s). Here, we present the first in vitro experiments carried out on cancer cells and normal non-transformed cells concurrently exposed to laser-plasma accelerated (LPA) electrons. Specifically, melanoma cancer cells and normal melanocyte co-cultures grown on chamber slides were simultaneously irradiated with LPA electrons. A non-uniform dose distribution on the cell cultures was revealed by Gafchromic films placed behind the chamber slide supporting the cells. In parallel experiments, cell co-cultures were exposed to pulsed X-ray irradiation, which served as positive controls for radiation-induced nuclear DNA double-strand breaks. By measuring the impact on discrete areas of the cell monolayers, the greatest proportion of the damaged DNA-containing nuclei was attained by the LPA electrons at a cumulative dose one order of magnitude lower than the dose obtained by pulsed X-ray irradiation. Interestingly, in certain discrete areas, we observed that LPA electron exposure had a different effect on the DNA damage in healthy normal human epidermal melanocyte (NHEM) cells than in A375 melanoma cells; here, the normal cells were less affected by the LPA exposure than cancer cells. This result is the first in vitro demonstration of a differential response of tumour and normal cells exposed to FLASH irradiation and may contribute to the development of new cell culture strategies to explore fundamental understanding of FLASH-induced cell effect.
Topics: Humans; Coculture Techniques; Electrons; Lasers; Cell Line, Tumor; Melanocytes; DNA Damage; Melanoma; DNA Breaks, Double-Stranded
PubMed: 38937505
DOI: 10.1038/s41598-024-65137-7 -
In Vivo (Athens, Greece) 2024ClFdA is a second-generation antineoplastic agent that has demonstrated significant anticancer activity, particularly against acute lymphoblastic leukemia and has been... (Review)
Review
BACKGROUND/AIM
ClFdA is a second-generation antineoplastic agent that has demonstrated significant anticancer activity, particularly against acute lymphoblastic leukemia and has been shown to have radiosensitizing activity. The aim of the study was to explore the genotoxic, cytotoxic and radiosensitizing effects of clofarabine (ClFdA) on bone marrow cells (BMCs), normoblasts and leukocytes of mice in vivo.
MATERIALS AND METHODS
Cytotoxicity was determined by the reduction in reticulocytes (RET), and genotoxicity was determined by the induction of micronucleated reticulocytes (MN-RET) in the peripheral blood and by DNA break induction in leukocytes determined by single-cell gel electrophoresis (SCGE). The radiosensitizing capacity of ClFdA was determined in leukocytes and BMCs by SCGE.
RESULTS
Two mechanisms of MN-RET induction were identified according to the antecedents, that could be due to inhibition of DNA synthesis and demethylation of G-C regions, and subsequent chromosome fragility. ClFdA cytotoxicity causes two contiguous peaks, an early peak that seems to inhibit MN-RET induction and a second peak that seems to be caused by ribonucleotide reductase (RR) and/or DNA synthesis inhibitions. ClFdA induced early DNA damage in noncycling leukocytes, and also radiosensitizes leukocytes immediately after treatment. ClFdA-ionizing radiation (IR) causes two time-dependent episodes of DNA damage, the latest after 80 min triggers a major breakage of DNA. In terms of the number of damaged cells, leukocytes and BMCs are similarly sensitive to ionizing radiation; BMCs are slightly more sensitive than leukocytes to ClFdA, but BMCs are doubly sensitive to combined treatment.
CONCLUSION
ClFdA causes early DNA damage and radiosensitivity in non-proliferating leukocytes, which rules out the most favored hypotheses of the participation of RR and DNA polymerase inhibition.
Topics: Animals; Clofarabine; Mice; Radiation-Sensitizing Agents; Leukocytes; DNA Damage; Arabinonucleosides; Bone Marrow Cells; Adenine Nucleotides; Male; Reticulocytes; Antineoplastic Agents; Micronucleus Tests
PubMed: 38936939
DOI: 10.21873/invivo.13622