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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 -
In Vivo (Athens, Greece) 2024There is concern that people who had COVID-19 will develop pulmonary fibrosis. Using mouse models, we compared pulmonary inflammation following injection of the spike...
BACKGROUND/AIM
There is concern that people who had COVID-19 will develop pulmonary fibrosis. Using mouse models, we compared pulmonary inflammation following injection of the spike protein of SARS-CoV-2 (COVID-19) to radiation-induced inflammation to demonstrate similarities between the two models. SARS-CoV-2 (COVID-19) induces inflammatory cytokines and stress responses, which are also common to ionizing irradiation-induced acute pulmonary damage. Cellular senescence, which is a late effect following exposure to SARS-CoV-2 as well as radiation, was investigated.
MATERIALS AND METHODS
We evaluated the effect of SARS-CoV-2 spike protein compared to ionizing irradiation in K18-hACE2 mouse lung, human lung cell lines, and in freshly explanted human lung. We measured reactive oxygen species, DNA double-strand breaks, stimulation of transforming growth factor-beta pathways, and cellular senescence following exposure to SARS-CoV-2 spike protein, irradiation or SARS-COV-2 and irradiation. We also measured the effects of the antioxidant radiation mitigator MMS350 following irradiation or exposure to SARS-CoV-2.
RESULTS
SARS-CoV-2 spike protein induced reactive oxygen species, DNA double-strand breaks, transforming growth factor-β signaling pathways, and senescence, which were exacerbated by prior or subsequent ionizing irradiation. The water-soluble radiation countermeasure, MMS350, reduced spike protein-induced changes.
CONCLUSION
In both the SARS-Co-2 and the irradiation mouse models, similar responses were seen indicating that irradiation or exposure to SARS-CoV-2 virus may lead to similar lung diseases such as pulmonary fibrosis. Combination of irradiation and SARS-CoV-2 may result in a more severe case of pulmonary fibrosis. Cellular senescence may explain some of the late effects of exposure to SARS-CoV-2 spike protein and to ionizing irradiation.
Topics: Animals; Mice; Humans; Spike Glycoprotein, Coronavirus; Oxidative Stress; Cellular Senescence; SARS-CoV-2; COVID-19; Lung; Reactive Oxygen Species; Disease Models, Animal; DNA Breaks, Double-Stranded; Cell Line; Transforming Growth Factor beta
PubMed: 38936937
DOI: 10.21873/invivo.13605 -
The Journal of Obstetrics and... Jun 2024To investigate the DNA damage response (DDR) in a cyclophosphamide (CTX)-induced mouse model of premature ovarian failure (POF).
AIM
To investigate the DNA damage response (DDR) in a cyclophosphamide (CTX)-induced mouse model of premature ovarian failure (POF).
METHODS
The POF model was established by injecting mice with CTX. The body, ovarian weights, the estrus cycle, and pathological changes of the ovaries were recorded. The serum levels of 17 β-estradiol (E2) and follicle-stimulating hormone (FSH) were measured. The expression of Ki67, β-galactosidase (β-gal), p21, p53, γH2AX, and pATM in ovarian tissues was detected by immunohistochemistry. The expression of β-gal, γH2AX, and pATM was analyzed by immunofluorescence staining of primary cultured granulosa cells (GCs).
RESULTS
The body and ovarian weights decreased, the estrus cycles were erratic, and the FSH level increased, whereas the E2 level decreased in POF mice compared to controls. The pathological consequences of POF revealed an increase in atretic follicles, corpus luteum, and primordial follicles and a decrease in the number of primary, secondary, and tertiary follicles. Ki67 expression was reduced, β-gal, p21, p53, γH2AX, and pATM expression were elevated in the ovaries of POF mice. The expression of β-gal, γH2AX, and pATM increased in GCs with the concentration in a time-dependent manner.
CONCLUSION
In total, CTX induced POF in mice, which was mediated by the DDR pathway of ATM-P53-P21.
PubMed: 38936810
DOI: 10.1111/jog.16004 -
Regulatory Toxicology and Pharmacology... Jun 2024Given the widespread applications in industrial and agricultural production, the health effects of rare earth elements (REEs) have garnered public attention, and the...
Given the widespread applications in industrial and agricultural production, the health effects of rare earth elements (REEs) have garnered public attention, and the genotoxicity of REEs remains unclear. In this study, we evaluated the genetic effects of lanthanum nitrate, a typical representative of REEs,with guideline-compliant in vivo and in vitro methods. Genotoxicity assays, including the Ames test, comet assay, mice bone marrow erythrocyte micronucleus test, spermatogonial chromosomal aberration test, and sperm malformation assay were conducted to assess mutagenicity, chromosomal damage, DNA damage, and sperm malformation. In the Ames test, no statistically significant increase in bacterial reverse mutation frequencies was found as compared with the negative control. Mice exposed to lanthanum nitrate did not exhibit a statistically significant increase in bone marrow erythrocyte micronucleus frequencies, spermatogonial chromosomal aberration frequencies, or sperm malformation frequencies compared to the negative control ( P > 0.05). Additionally, after a 24-hour treatment with lanthanum nitrate at concentrations of 1.25, 5, and 20 μg/ml, no cytotoxicity was observed in CHL cells. Furthermore, the comet assay results indicate no significant DNA damage was observed even after exposure to high doses of lanthanum nitrate (20 μg/ml). In conclusion, our findings suggest that lanthanum nitrate does not exhibit genotoxicity.
PubMed: 38936798
DOI: 10.1016/j.yrtph.2024.105670 -
Biochimica Et Biophysica Acta.... Jun 2024Three-dimensional (3D) organoids derived from human pluripotent stem cells (hPSCs) have revolutionized in vitro tissue modeling, offering a unique opportunity to...
BACKGROUND
Three-dimensional (3D) organoids derived from human pluripotent stem cells (hPSCs) have revolutionized in vitro tissue modeling, offering a unique opportunity to replicate physiological tissue organization and functionality. This study investigates the impact of radiation on skeletal muscle response using an innovative in vitro human 3D skeletal muscle organoids (hSMOs) model derived from hPSCs.
METHODS
The hSMOs model was established through a differentiation protocol faithfully recapitulating embryonic myogenesis and maturation via paraxial mesodermal differentiation of hPSCs. Key skeletal muscle characteristics were confirmed using immunofluorescent staining and RT-qPCR. Subsequently, the hSMOs were exposed to a clinically relevant dose of 2 Gy of radiation, and their response was analyzed using immunofluorescent staining and RNA-seq.
RESULTS
The hSMO model faithfully recapitulated embryonic myogenesis and maturation, maintaining key skeletal muscle characteristics. Following exposure to 2 Gy of radiation, histopathological analysis revealed deficits in hSMOs expansion, differentiation, and repair response across various cell types at early (30 min) and intermediate (18 h) time points post-radiation. Immunofluorescent staining targeting γH2AX and 53BP1 demonstrated elevated levels of foci per cell, particularly in PAX7 cells, during early and intermediate time points, with a distinct kinetic pattern showing a decrease at 72 h. RNA-seq data provided comprehensive insights into the DNA damage response within the hSMOs.
CONCLUSIONS
Our findings highlight deficits in expansion, differentiation, and repair response in hSMOs following radiation exposure, enhancing our understanding of radiation effects on skeletal muscle and contributing to strategies for mitigating radiation-induced damage in this context.
PubMed: 38936620
DOI: 10.1016/j.bbamcr.2024.119792