Role of miR-93-5p and Its Opposing Effect of Ionizing Radiation in Non-Small Cell Lung Cancer.

Background: Radiation therapy is an effective local therapy for lung cancer. However, the interaction between genes and radiotherapy is multifaceted and intricate. Therefore, we explored the role of miR-93-5p in the proliferation, apoptosis, and migration abilities of A549 cells. Simultaneously, we also investigated the interactions between miR-93-5p and ionizing radiation (IR). Methods: Cell Counting Kit-8, transwell, and apoptotic assay were performed to measure the proliferation, migration, and apoptosis abilities. The expression levels of miR-93-5p and its target gene in lung cancer were predicted using starBase v3.0. Then, data were validated using qPCR and western blot. Results: miR-93-5p significantly promoted the proliferation (P < 0.01) and migration abilities (P < 0.001) of A549 cells. Gasdermin E (GSDME) was identified to be a putative target of miR-93-5p and had a negative correlation with miR-93-5p (P < 0.001). Overexpression of miR-93-5p significantly decreased GSDME in A549 (P < 0.001). Interestingly, miR-93-5p decreased cell proliferation (P < 0.01) and cell migration (P < 0.01) and increased apoptosis (P < 0.01) in A549 cells after exposure to IR. Conclusions: miR-93-5p is presumed to play an oncogenic role in lung cancer by enhancing A549 cell proliferation and migration. It can enhance the sensitivity of radiotherapy under IR conditions. We speculate that the miR-93-5p/GSDME pathway was inhibited, activating the GSDME-related pyroptosis pathway when the cells were exposed to IR. Therefore, miR-93-5p can overcome resistance to radiotherapy and improve the efficacy of radiotherapy.

Photobiomodulation therapy mitigates depressive-like behaviors by remodeling synaptic links and mitochondrial function.

Depression, a multifactorial mental disorder, characterized by cognitive slowing, anxiety, and impaired cognitive function, imposes a significant burden on public health. Photobiomodulation (PBM), involving exposure to sunlight or artificial light at a specific intensity and wavelength for a determined duration, influences brain activity, functional connectivity, and plasticity. It is recognized for its therapeutic efficacy in treating depression, yet its molecular and cellular underpinnings remain obscure. Here, we investigated the impact of PBM with 468 nm light on depression-like behavior and neuronal damage in the chronic unpredictable mild stress (CUMS) murine model, a commonly employed animal model for studying depression. Our results demonstrate that PBM treatment ameliorated behavioral deficits, inhibited neuroinflammation and apoptosis, and notably rejuvenates the hippocampal synaptic function in depressed mice, which may be mainly attributed to the up-regulation of brain-derived neurotrophic factor signaling pathways. In addition, in vitro experiments with a corticosterone-induced hippocampal neuron injury model demonstrate reduced oxidative stress and improved mitochondrial function, further validating the therapeutic potential of PBM. In summary, these findings suggest PBM as a promising, non-invasive treatment for depression, offering insights into its biological mechanisms and potential for clinical application.

Blue light photobiomodulation induced osteosarcoma cell death by facilitating ferroptosis and eliciting an incomplete tumor cell stress response.

To investigate the potential of blue light photobiomodulation (PBM) in inducing ferroptosis, a novel form of regulated cell death, in OS cells, considering its known effectiveness in various cancer models. In this investigation, we exposed human OS cell lines, HOS and MG63, to different wavelengths (420, 460 and 480 nm) of blue light at varying irradiances, and examined cellular responses such as viability, apoptosis, levels of reactive oxygen species (ROS), and mitochondrial membrane potential (MMP). Transcriptome sequencing was employed to unravel the molecular mechanisms underlying blue light-induced effects, with validation via quantitative real-time PCR (qRT-PCR). Our findings revealed a wavelength- and time-dependent decrease in cell viability, accompanied by increased apoptosis and oxidative stress. Transcriptomic analysis identified differential expression of genes associated with ferroptosis, oxidative stress, and iron metabolism, further validated by qRT-PCR. These results implicated ferroptosis as a significant mechanism in the blue light-induced death of OS cells, potentially mediated by ROS generation and disruption of iron homeostasis. Also, An incomplete stress response was observed in MG63 cells induced by blue light exposure. Hence, blue light PBM holds promise as a therapeutic approach in OS clinical investigations; however, additional exploration of its underlying mechanisms remains imperative.

Mitochondrial Targeted Cerium Oxide Nanoclusters for Radiation Protection and Promoting Hematopoiesis.

Purpose: Mitochondrial oxidative stress is an important factor in cell apoptosis. Cerium oxide nanomaterials show great potential for scavenging free radicals and simulating superoxide dismutase (SOD) and catalase (CAT) activities. To solve the problem of poor targeting of cerium oxide nanomaterials, we designed albumin-cerium oxide nanoclusters (TPP-PCNLs) that target the modification of mitochondria with triphenyl phosphate (TPP). TPP-PCNLs are expected to simulate the activity of superoxide dismutase, continuously remove reactive oxygen species, and play a lasting role in radiation protection. Methods: First, cerium dioxide nanoclusters (CNLs), polyethylene glycol cerium dioxide nanoclusters (PCNLs), and TPP-PCNLs were characterized in terms of their morphology and size, ultraviolet spectrum, dispersion stability and cellular uptake, and colocalization Subsequently, the anti-radiation effects of TPP-PCNLs were investigated using in vitro and in vivo experiments including cell viability, apoptosis, comet assays, histopathology, and dose reduction factor (DRF). Results: TPP-PCNLs exhibited good stability and biocompatibility. In vitro experiments indicated that TPP-PCNLs could not only target mitochondria excellently but also regulate reactive oxygen species (ROS)levels in whole cells. More importantly, TPP-PCNLs improved the integrity and functionality of mitochondria in irradiated L-02 cells, thereby indirectly eliminating the continuous damage to nuclear DNA caused by mitochondrial oxidative stress. TPP-PCNLs are mainly targeted to the liver, spleen, and other extramedullary hematopoietic organs with a radiation dose reduction factor of 1.30. In vivo experiments showed that TPP-PCNLs effectively improved the survival rate, weight change, hematopoietic function of irradiated animals. Western blot experiments have confirmed that TPP-PCNLs play a role in radiation protection by regulating the mitochondrial apoptotic pathway. Conclusion: TPP-PCNLs play a radiologically protective role by targeting extramedullary hematopoietic organ-liver cells and mitochondria to continuously clear ROS.

Antitumour effects of SFX-01 molecule in combination with ionizing radiation in preclinical and in vivo models of rhabdomyosarcoma.

BACKGROUND: Despite a multimodal approach including surgery, chemo- and radiotherapy, the 5-year event-free survival rate for rhabdomyosarcoma (RMS), the most common soft tissue sarcoma in childhood, remains very poor for metastatic patients, mainly due to the selection and proliferation of tumour cells driving resistance mechanisms. Personalised medicine-based protocols using new drugs or targeted therapies in combination with conventional treatments have the potential to enhance the therapeutic effects, while minimizing damage to healthy tissues in a wide range of human malignancies, with several clinical trials being started. In this study, we analysed, for the first time, the antitumour activity of SFX-01, a complex of synthetic d, l-sulforaphane stabilised in alpha-cyclodextrin (Evgen Pharma plc, UK), used as single agent and in combination with irradiation, in four preclinical models of alveolar and embryonal RMS. Indeed, SFX-01 has shown promise in preclinical studies for its ability to modulate cellular pathways involved in inflammation and oxidative stress that are essential to be controlled in cancer treatment. METHODS: RH30, RH4 (alveolar RMS), RD and JR1 (embryonal RMS) cell lines as well as mouse xenograft models of RMS were used to evaluate the biological and molecular effects induced by SFX-01 treatment. Flow cytometry and the modulation of key markers analysed by q-PCR and Western blot were used to assess cell proliferation, apoptosis, autophagy and production of intracellular reactive oxygen species (ROS) in RMS cells exposed to SFX-01. The ability to migrate and invade was also investigated with specific assays. The possible synergistic effects between SFX-01 and ionising radiation (IR) was studied in both the in vitro and in vivo studies. Student's t-test or two-way ANOVA were used to test the statistical significance of two or more comparisons, respectively. RESULTS: SFX-01 treatment exhibited cytostatic and cytotoxic effects, mediated by G2 cell cycle arrest, apoptosis induction and suppression of autophagy. Moreover, SFX-01 was able to inhibit the formation and the proliferation of 3D tumorspheres as monotherapy and in combination with IR. Finally, SFX-01, when orally administered as single agent, displayed a pattern of efficacy at reducing the growth of tumour masses in RMS xenograft mouse models; when combined with a radiotherapy regime, it was observed to act synergistically, resulting in a more positive outcome than would be expected by adding each exposure alone. CONCLUSIONS: In summary, our results provide evidence for the antitumour properties of SFX-01 in preclinical models of RMS tumours, both as a standalone treatment and in combination with irradiation. These forthcoming findings are crucial for deeper investigations of SFX-01 molecular mechanisms against RMS and for setting up clinical trials in RMS patients in order to use the SFX-01/IR co-treatment as a promising therapeutic approach, particularly in the clinical management of aggressive RMS disease.

Decrease of alpha-crystallin A by miR-325-3p in retinal cells under blue light exposure.

Exposure to blue light can lead to retinal degeneration, causing adverse effects on eye health. Although the loss of retinal cells due to blue light exposure has been observed, the precise molecular mechanisms underlying this process remain poorly understood. In this study, we investigate the role of alpha-crystallin A (CRYAA) in neuro-retinal degeneration and their regulation by blue light. We observed significant apoptotic cell death in both the retina of rats and the cultured neuro-retinal cells. The expressions of Cryaa mRNA and protein were significantly downregulated in the retina exposed to blue light. We identified that miR-325-3p reduces Cryaa mRNA and protein by binding to its 3'-untranslated region. Upregulation of miR-325-3p destabilized Cryaa mRNA and suppresses CRYAA, whereas downregulation of miR-325-3p increased both expressions. Blue light-induced neuro-retinal cell death was alleviated by CRYAA overexpression. These results highlight the critical role of Cryaa mRNA and miR-325-3p molecular axis in blue light-induced retinal degeneration. Consequently, targeting CRYAA and miR-325-3p presents a potential strategy for protecting against blue light-induced retinal degeneration.

Synergistic Effect of Doxorubicin and Blue Light Irradiation on the Antitumor Treatment of HepG2 Cells in Liver Cancer.

Doxorubicin (DOX) has been an effective antitumor agent for human liver cancer cells; however, an overdose might lead to major side effects appearing in clinical applications. In this work, we present a strategy of combining DOX and blue light (BL) irradiation for the antitumor treatment of HepG2 cells (one typical human liver cancer cell line). It is demonstrated that synergetic DOX and BL can significantly reduce cell proliferation and increase the apoptotic rate of HepG2 cells in comparison to individual DOX treatment. The additional BL irradiation is further helpful for enhancing the inhibition of cell migration and invasion. Analyses of reactive oxygen species (ROS) level and Western blotting reveal that the strategy results in more ROS accumulation, mitochondrial damage, and the upregulation of proapoptotic protein (Bcl-2) and downregulation of antiapoptotic protein (Bax). In addition to the improved therapeutic effect, the non-contact BL irradiation is greatly helpful for reducing the dosage of DOX, and subsequently reduces the side effects caused by the DOX drug. These findings offer a novel perspective for the therapeutic approach toward liver cancer with high efficiency and reduced side effects.

Sulforaphane Effects on Neuronal-like Cells and Peripheral Blood Mononuclear Cells Exposed to 2.45 GHz Electromagnetic Radiation.

Exposure to 2.45 GHz electromagnetic radiation (EMR) emitted from commonly used devices has been reported to induce oxidative stress in several experimental models. Our study aims to evaluate the efficacy of sulforaphane, a well-known natural product, in preventing radiation-induced toxic effects caused by a 24 h exposure of SH-SY5Y neuronal-like cells and peripheral blood mononuclear cells (PBMCs) to 2.45 GHz EMR. Cells were exposed to radiation for 24 h in the presence or absence of sulforaphane at different concentrations (5-10-25 µg/mL). Cell viability, mitochondrial activity alterations, the transcription and protein levels of redox markers, and apoptosis-related genes were investigated. Our data showed a reduction in cell viability of both neuronal-like cells and PBMCs caused by EMR exposure and a protective effect of 5 µg/mL sulforaphane. The lowest sulforaphane concentration decreased ROS production and increased the Mitochondrial Transmembrane Potential (Δψm) and the NAD+/NADH ratio, which were altered by radiation exposure. Sulforaphane at higher concentrations displayed harmful effects. The hormetic behavior of sulforaphane was also evident after evaluating the expression of genes coding for Nrf2, SOD2, and changes in apoptosis markers. Our study underlined the vulnerability of neuronal-like cells to mitochondrial dysfunction and oxidative stress and the possibility of mitigating these effects by supplementation with sulforaphane. To our knowledge, there are no previous studies about the effects of SFN on these cells when exposed to 2.45 GHz electromagnetic radiation.

[Circ_0000263 improves radiosensitivity of Hela cells by inhibiting the activity of telomerase protein through miR-338-3p/TERT].

Objective: To explore the effect and molecular mechanism of circ_0000263 on HeLa cell activity, apoptosis, telomerase activity, and radiosensitivity. Methods: The Hela cells were divided into si-NC, si-circ, vector, circ_0000263, anti-NC, anti-miR-338-3p, miR-NC, miR-338-3p, si-circ+anti-NC, si-circ+ anti-miR-338-3p, si-circ+vector, si-circ+TERT, sh-NC, sh-circ groups. Reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) was used to detect the expressions of circ_0000263 and miR-338-3p. Cell clone formation array was used to detect cell survival; cell counting kit-8 (CCK-8) to detect cell proliferation; flow cytometry to detect apoptosis; western blot method to detect the expressions of proliferating cell nuclear antigen (PCNA), Cleaved-casp3, telomerase reverse transcriptase (TERT) proteins; double luciferase assay to detect the targeting relationships of circ_0000263 and miR-338-3p, miR-338-3p and TERT; telomere repeat amplification enzyme linked immunosorbent assay (TRAR-ELISA) to detect telomerase activity. Results: Circ_0000263 was highly expressed in Hela cells, miR-338-3p was low expressed, and TERT was highly expressed; circ_0000263 was also highly expressed in Hela cells treated with radiation (P＜0.05). Knockdown of circ_0000263 inhibited the clone formation and cell proliferation ability of HeLa cells, and enhanced the radiosensitivity and apoptosis of HeLa cells. In contrast, knockdown of circ_0000263 decreased PCNA protein expression level and enhanced Cleaved-casp3 protein expression level in HeLa cells (P＜0.05). The apoptosis rate in the si-circ group was (13.19±1.12)%, which was higher than (6.80±0.62)% of si-NC group (P＜0.05). The apoptosis rate in the si-circ+4 Gy group was (24.82±1.57)%, which was higher than (17.00±0.96)% of si-NC+4 Gy group (P＜0.05). Circ_0000263 targeted regulated miR-338-3p, and miR-338-3p targeted regulated TERT. MiR-338-3p was lowly expressed in HeLa cells, and knockdown of circ_0000263 elevated miR-338-3p expression level in HeLa cells. Circ_0000263 regulated TERT expression and inhibited telomerase activity through miR-338-3p. MiR-338-3p/TERT can restore the effect of circ_0000263 on the radiosensitivity of Hela cells. The apoptosis rate in the si-circ+anti-NC group was (27.37±0.89)%, which was higher than (18.22±1.18)% of the si-circ+anti-miR-338-3p group (P＜0.05). The apoptosis rate in the si-circ+vector group was (27.55±0.48)%, which was higher than (20.10±0.68)% of si-circ+TERT group (P＜0.05). After 72 hours of radiation by 4 Gy, the cell survival fraction of si-circ+anti-NC group was 0.41±0.02, which was lower than 0.66±0.03 of the si-circ+anti-miR-338-3p group (P＜0.05); the cell survival fraction of si-circ+vector group was 0.42±0.05, which was lower than 0.70±0.03 of si-circ+TERT group (P＜0.05). Conclusion: Inhibiting the expression of circ_0000263 supresses the proliferation of Hela cells by regulating miR-338-3p/TERT, promotes apoptosis, inhibits telomerase activity, increases the radiosensitivity of cancer cells, and provides a theoretical basis for improving the radiosensitivity of Hela cells.

Uvaol ameliorates lipid deposition in hyperlipidemic hepatocytes by suppressing protein-tyrosine phosphatase 1B/ER stress signaling.

Uvaol (UV), a pentacyclic triterpene found in olives and virgin olive oil, is known for its anti-inflammatory and antioxidant effects in various disease models. While olive oil is reported to reduce obesity and insulin resistance, the specific impact of UV on liver lipid metabolism and its molecular mechanisms are not fully understood. In this study, hepatic lipid accumulation was measured using oil red O staining, and protein expression levels in liver cells were assessed via Western blot analysis. Apoptosis was evaluated through cell viability and caspase 3 activity assays. UV treatment reduced lipid accumulation, fatty acid uptake, apoptosis, and ER stress in palmitate-treated liver cells. Additionally, UV enhanced fatty acid oxidation. Mechanistically, increased SIRT6 expression and autophagy were observed in UV-treated cells. SIRT6-targeted siRNA or 3-methyladenine blocked the effects of UV in hyperlipidemic cells. In conclusion, UV improves SIRT6/autophagy signaling, reducing lipid deposition and apoptosis in liver cells under high lipid conditions. This in vitro study provides strong evidence for potential therapeutic strategies for hepatic steatosis.

The protective effect of Artemisia Capillaris Thunb. Extract against UVB-induced apoptosis and inflammation through inhibiting the cGAS/STING pathway.

Exposure to ultraviolet B (UVB) radiation represents a significant environmental threat to human skin. This study investigates the protective mechanism of Artemisia Capillaris Thunb. (AC) extract against UVB-induced apoptosis and inflammation in HaCaT keratinocytes. AC extract demonstrated a significant protective effect, as evidenced by reduced early apoptosis, late apoptosis, and necrosis, as well as decreased apoptotic cell status upon UVB exposure. Additionally, AC extract effectively inhibited UVB-induced DNA damage, as indicated by diminished γ-H2AX foci formation. Restoration of mitochondrial damage and normalization of mitochondrial membrane potential, along with the reduction of intracellular and mitochondrial reactive oxygen species (ROS) levels, were observed with AC extract pre-treatment. The extract also exhibited anti-inflammatory properties, evidenced by the decreased release of IL-1α, IL-6, and PGE2 from keratinocytes. Additional research on the molecular mechanisms uncovered that the AC extract alters the cGAS/STING pathway, suppressing the mRNA (cGAS, STING, IRF3, IRF7 and TBK1) and protein levels (cGAS, STING, IRF3, IRF7 and NF-κB) linked to this particular pathway. The HPLC analysis identified chlorogenic acid and its derivatives as the major components in AC, constituting up to 16.44% of the total chlorogenic acid content. The cGAS/STING signaling pathway was found to be suppressed by chlorogenic acid and its derivatives, as indicated by molecular docking studies and RT-qPCR analysis. This suppression contributes to the protective effects against cell apoptosis and inflammation induced by UVB. To summarize, AC extract, which is abundant in chlorogenic acid and its derivatives, shows potential in protecting keratinocytes from damage caused by UVB by regulating the cGAS/STING signaling pathway.

Photobiomodulation improves cell survival and death parameters in cardiomyocytes exposed to hypoxia/reoxygenation.

INTRODUCTION: Cardiovascular diseases are the leading cause of morbidity and mortality worldwide. Ischemic heart disease is one of the most harmful conditions to cellular structure and function. After reperfusion treatment, a spectrum of adverse effects becomes evident, encompassing altered cell viability, heightened oxidative stress, activated autophagy, and increased apoptosis. Photobiomodulation (PBM) has been utilized in experimental models of cardiac hypoxia to enhance mitochondrial response and ameliorate biochemical changes in injured tissue. However, the effects of PBM on cultured cardiomyocytes subjected to hypoxia/reoxygenation are not yet well established. METHOD: H9C2 cardiomyocytes were exposed to hypoxia with concentrations of 300 µM CoCl2 for 24 h, followed by 16 h of reoxygenation through incubation in a normoxic medium. Treatment was conducted using GaAIAs Laser (850 nm) after hypoxia at an intensity of 1 J/cm2. Cells were divided into three groups: Group CT (cells maintained under normoxic conditions), Group HR (cells maintained in hypoxia and reoxygenation conditions without treatment), Group HR + PBM (cells maintained in hypoxia and reoxygenation conditions that underwent PBM treatment). Cell viability was analyzed using MTT, and protein expression was assessed by western blot. One-way ANOVA with the Tukey post hoc test was used for data analysis. Differences were significant when p < 0.05. RESULTS: PBM at an intensity of 1 J/cm2 mitigated the alterations in cell survival caused by hypoxia/reoxygenation. Additionally, it significantly increased the expression of proteins Nrf2, HSP70, mTOR, LC3II, LC3II/I, and Caspase-9, while reducing the expression of PGC-1α, SOD2, xanthine oxidase, Beclin-1, LC3I, and Bax. CONCLUSION: PBM at intensities of 1 J/cm2 reverses the changes related to oxidative stress, mitochondrial biogenesis, autophagy, and apoptosis caused by hypoxia and reoxygenation in a culture of cardiomyocytes.

The Extremely-Low-Frequency Electromagnetic Field Affects Apoptosis and Oxidative-Stress-Related Genes and Proteins in the Porcine Endometrium-An In Vitro Study.

Nowadays, the extremely-low-frequency electromagnetic field (ELF-EMF) is recognized as environmental pollution. The data indicate that the ELF-EMF may affect factors related to epigenetic regulation and alter important biological processes in the uterus. The impact of the ELF-EMF on apoptosis and oxidative-stress-related genes has not been documented in porcine endometrium. This raises the question of whether the exposure to the ELF-EMF can induce apoptosis and/or oxidative stress in the endometrium of pigs during the peri-implantation period. Porcine endometrial slices (100 ± 5 mg) collected (n = 5) during the peri-implantation period were treated in vitro with ELF-EMF at a frequency of 50 Hz and flux density of 8 × 104 mG for 2 h. To determine the effect of ELF-EMF on apoptosis and oxidative stress in the endometrium, CASP3, CASP7, CIDEB, GADD45G, NOS1, NOS2, NOS3, and TP53I3 mRNA transcript were analyzed using real-time PCR, and protein abundance of CASP3, CASP7 using Western blot, and eNOS using ELISA were determined. Moreover, CASP3/7 and NOS activity was analyzed using flow cytometry and colorimetry, respectively. The decreased CASP7 and increased NOS3 mRNA transcript and protein abundance in ELF-EMF-treated endometrium were observed. Moreover, CIDEB, GADD45G, and TP53I3 mRNA transcript abundance was increased. Only p ≤ 0.05 was considered a statistically significant difference. The documented alterations indicate the potential of the ELF-EMF to affect apoptosis and generate oxidative stress in the endometrium. The insight into observed consequences documents for the first time the fact that the ELF-EMF may influence endometrial cell proliferation, angiogenesis, and/or tissue receptivity during peri-implantation.

Far-Ultraviolet Light at 222 nm Affects Membrane Integrity in Monolayered DLD1 Colon Cancer Cells.

222 nm far-ultraviolet (F-UV) light has a bactericidal effect similar to deep-ultraviolet (D-UV) light of about a 260 nm wavelength. The cytotoxic effect of 222 nm F-UV has not been fully investigated. DLD-1 cells were cultured in a monolayer and irradiated with 222 nm F-UV or 254 nm D-UV. The cytotoxicity of the two different wavelengths of UV light was compared. Changes in cell morphology after F-UV irradiation were observed by time-lapse imaging. Differences in the staining images of DNA-binding agents Syto9 and propidium iodide (PI) and the amount of cyclobutane pyrimidine dimer (CPD) were examined after UV irradiation. F-UV was cytotoxic to the monolayer culture of DLD-1 cells in a radiant energy-dependent manner. When radiant energy was set to 30 mJ/cm2, F-UV and D-UV showed comparable cytotoxicity. DLD-1 cells began to expand immediately after 222 nm F-UV light irradiation, and many cells incorporated PI; in contrast, PI uptake was at a low level after D-UV irradiation. The amount of CPD, an indicator of DNA damage, was higher in cells irradiated with D-UV than in cells irradiated with F-UV. This study proved that D-UV induced apoptosis from DNA damage, whereas F-UV affected membrane integrity in monolayer cells.

Additive antitumor effect of arsenic trioxide with exposure to ionizing radiation to human acute promyelocytic leukemia HL­60 cells.

Arsenic trioxide (ATO) is expected to be a chemical drug with antitumor activity against acute promyelocytic leukemia (APL), a type of acute myeloid leukemia. In Japan, its antitumor effects were confirmed in clinical trials for APL, and it has been approved in various countries around the world. However, there have been no reports on ATO's antitumor effects on radioresistant leukemia cells, which can be developed during radiotherapy and in combination with therapeutic radiation beams. The present study sought to clarify the antitumor effect of ATO on APL cells with radiation resistance and determine its efficacy when combined with ionizing radiation (IR). The radiation­resistant HL60 (Res­HL60) cell line was generated by subjecting the native cells to 4­Gy irradiation every week for 4 weeks. The half­maximal inhibitory concentration (IC50) for cell proliferation by ATO on native cell was 0.87 µM (R2=0.67), while the IC50 for cell proliferation by ATO on Res­HL60 was 2.24 µM (R2=0.91). IR exposure increased the sub­G1 and G2/M phase ratios in both cell lines. The addition of ATO resulted in a higher population of G2/M after 24 h rather than 48 h. When the rate of change in the sub­G1 phase was examined in greater detail, the sub­G1 phase in both control cells without ATO significantly increased by exposure to IR at 24 h, but only under the condition of 2 Gy irradiation, it had continued to increase at 48 h. Res­HL60 supplemented with ATO showed a higher rate of sub­G1 change at 24 h; however, 2 Gy irradiation resulted in a decrease compared with the control. There was a significant increase in the ratio of the G2/M phase in cells after incubation with ATO for 24 h, and exposure to 2 Gy irradiation caused an even greater increase. To determine whether the inhibition of cell proliferation and cell cycle disruptions is related to reactive oxygen species (ROS) activity, intracellular ROS levels were measured with a flow cytometric assay. Although the ROS levels of Res­HL60 were higher than those of native cells in the absence of irradiation, they did not change after 0.5 or 2 Gy irradiation. Furthermore, adding ATO to Res­HL60 reduced intracellular ROS levels. These findings provide important information that radioresistant leukemia cells respond differently to the antitumor effect of ATO and the combined effect of IR.

A role for YAP/FOXM1/Nrf2 axis in oxidative stress and apoptosis of cataract induced by UVB irradiation.

This study aims to investigate the hypothesis that Yes-associated protein (YAP) significantly regulates antioxidant potential and anti-apoptosis in UVB-induced cataract by exploring the underlying molecular mechanisms. To investigate the association between YAP and cataract, various experimental techniques were employed, including cell viability assessment, Annexin V FITC/PI assay, measurement of ROS production, RT-PCR, Western blot assay, and Immunoprecipitation. UVB exposure on human lens epithelium cells (HLECs) reduced total and nuclear YAP protein expression, increased cleaved/pro-caspase 3 ratios, decreased cell viability, and elevated ROS levels compared to controls. Similar Western blot results were observed in in vivo experiments involving UVB-treated mice. YAP knockdown in vitro demonstrated a decrease in the protein expression of FOXM1, Nrf2, and HO-1, which correlated with the mRNA expression, accompanied by an increase in cell apoptosis, caspase 3 activation, and the release of ROS. Conversely, YAP overexpression mitigated these effects induced by UVB irradiation. Immunoprecipitation revealed a FOXM1-YAP interaction. Notably, inhibiting FOXM1 decreased Nrf2 and HO-1, activating caspase 3. Additionally, administering the ROS inhibitor N-acetyl-L-cysteine (NAC) effectively mitigated the apoptotic effects induced by oxidative stress from UVB irradiation, rescuing the protein expression levels of YAP, FOXM1, Nrf2, and HO-1. The initial findings of our study demonstrate the existence of a feedback loop involving YAP, FOXM1, Nrf2, and ROS that significantly influences the cell apoptosis in HLECs under UVB-induced oxidative stress.

Synergistic Effects of 125I Seed Implantation Brachytherapy and Gemcitabine in Pancreatic Tumors.

BACKGROUND: Monotherapy consisting of radiotherapy or chemotherapy has limited efficacy in pancreatic tumors. This study aims to investigate whether the combination of 125I brachytherapy and gemcitabine (GEM) chemotherapy has a synergistic effect on pancreatic cancer (PC). METHODS: In vitro, PANC-1 cells in the exponential phase were treated with 125I radioactive seeds (6 Gy) and GEM (30 nM). Cell proliferation, apoptosis, and mitochondrial membrane potential were measured using the Cell Counting Kit-8 (CCK-8) assay, Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining, and flow cytometry, respectively. In vivo, we examined the inhibitory effect of three different treatment regimens on tumor growth in mice when combined with 125I brachytherapy and GEM. Next, we investigated the effects of the optimal scheme among the three on the tumor microenvironment, tumor tissue morphology, tumor cell apoptosis, systemic inflammatory response, and levels of apoptosis-related proteins in the tumor. Changes in the tumor microenvironment and levels of apoptosis-related proteins were measured by Western blot. The extent of damage to tumor tissue morphology was assessed by Hematoxylin and Eosin (HE) staining. Tumor cell apoptosis was measured by TUNEL staining. Changes in inflammation-related factors were determined by Enzyme-Linked Immunosorbent Assay (ELISA). RESULTS: The results of in vitro cell experiments demonstrated that the combination of 125I radioactive seeds (6 Gy) and GEM (30 nM) had a stronger inhibitory effect on PANC-1 cells than either alone (p < 0.05). In vivo, data showed that the GEM (after 3 d) + 125I treatment group had the strongest tumor inhibition effect on PC (p < 0.05). Western blot analysis showed that the combined treatment of 125I brachytherapy and GEM caused changes in the expression of collagen and connexin in the tumor microenvironment, promoted tumor cell apoptosis, upregulated the expression of pro-apoptotic proteins, and helped to restore pancreatic function (p < 0.01). CONCLUSION: Our research results suggest that the strategy of 125I seed implantation surgery in mice after 3 days of GEM treatment has a more pronounced synergistic effect on the treatment of PC.

Protective effect and mechanism of Lycium ruthenicum Murray anthocyanins against retinal damage induced by blue light exposure.

Lycium ruthenicum Murray (LR) is a medicine and edible plant in Northwest China, and L. ruthenicum Murray anthocyanins (LRA) are green antioxidants with various pharmacological activities, such as antioxidant and anti-inflammatory activities. However, the protective effect and mechanism of LRA against retinal damage induced by blue light exposure are poorly understood. This study explored the protective effects and potential mechanisms of LRA on retinal damage induced by blue light exposure in vitro and in vivo. The results showed that LRA could ameliorate oxidative stress injury by activating the antioxidant stress nuclear factor-related factor 2 pathway, promoting the expression of phase II detoxification enzymes (HO-1, NQO1) and endogenous antioxidant enzymes (catalase, superoxide dismutase, glutathione peroxidase), and reducing reactive oxygen species and malondialdehyde levels. Additionally, LRA could inhibit inflammatory response by decreasing the expression of blue light exposure-induced nuclear factor-κB (NF-κB) pathway-related proteins (NF-κB and p-IκBα), as well as interleukin (IL)-6, tumor necrosis factor-α, IL-1ß pro-inflammatory factors and pro-inflammatory chemokine VEGF, and increasing the expression of anti-inflammatory factor IL-10. Furthermore, LRA could ameliorate oxidative stress-induced apoptosis by upregulating Bcl-2 and downregulating Bax and Caspase-3 protein expression. All these results indicate that LRA can be used as an antioxidant dietary supplement for the treatment or prevention of retinal diseases.

APR-246 as a radiosensitization strategy for mutant p53 cancers treated with alpha-particles-based radiotherapy.

Radiation therapy (RT) remains a common treatment for cancer patients worldwide, despite the development of targeted biological compounds and immunotherapeutic drugs. The challenge in RT lies in delivering a lethal dose to the cancerous site while sparing the surrounding healthy tissues. Low linear energy transfer (low-LET) and high linear energy transfer (high-LET) radiations have distinct effects on cells. High-LET radiation, such as alpha particles, induces clustered DNA double-strand breaks (DSBs), potentially inducing cell death more effectively. However, due to limited range, alpha-particle therapies have been restricted. In human cancer, mutations in TP53 (encoding for the p53 tumor suppressor) are the most common genetic alteration. It was previously reported that cells carrying wild-type (WT) p53 exhibit accelerated senescence and significant rates of apoptosis in response to RT, whereas cells harboring mutant p53 (mutp53) do not. This study investigated the combination of the alpha-emitting atoms RT based on internal Radium-224 (224Ra) sources and systemic APR-246 (a p53 reactivating compound) to treat tumors with mutant p53. Cellular models of colorectal cancer (CRC) or pancreatic ductal adenocarcinoma (PDAC) harboring mutant p53, were exposed to alpha particles, and tumor xenografts with mutant p53 were treated using 224Ra source and APR-246. Effects on cell survival and tumor growth, were assessed. The spread of alpha emitters in tumors was also evaluated as well as the spatial distribution of apoptosis within the treated tumors. We show that mutant p53 cancer cells exhibit radio-sensitivity to alpha particles in vitro and to alpha-particles-based RT in vivo. APR-246 treatment enhanced sensitivity to alpha radiation, leading to reduced tumor growth and increased rates of tumor eradication. Combining alpha-particles-based RT with p53 restoration via APR-246 triggered cell death, resulting in improved therapeutic outcomes. Further preclinical and clinical studies are needed to provide a promising approach for improving treatment outcomes in patients with mutant p53 tumors.

Stereotactic body radiation therapy suppresses myeloid-derived suppressor cells by regulating miR-21/Sorbin and SH3 Domain-containing Protein 1 axis.

BACKGROUND: Stereotactic body radiation therapy (SBRT) is a targeted form of radiotherapy used to treat early-stage cancers. Despite its effectiveness, the impact of SBRT on myeloid-derived suppressor cells (MDSCs) is not well understood. In this study, we examined how SBRT affects the differentiation and survival of MDSCs, as well as delved into the molecular mechanisms involved. METHODS AND RESULTS: SBRT was utilized on bone marrow (BM)-derived MDSCs to investigate its impact on the differentiation and survival of MDSCs using flow cytometry. An animal model of lung cancer was created to assess the anti-cancer properties of SBRT and the role of miR-21 expression in MDSCs. The interplay of miR-21 and Sorbin and SH3 domain-containing protein 1 (SORBS1) in MDSC differentiation was explored through dual luciferase activity assay, RT-qPCR, and Western blot analysis. The findings suggest that SBRT led to an increase in miR-21 levels, inhibited MDSC differentiation, and triggered cell apoptosis in BM cells. Inhibition of miR-21 reversed the effects of SBRT on MDSC differentiation and apoptosis. Additionally, it was revealed that SORBS1 was a downstream target of miR-21 in BM cells, and the miR-21/SORBS1 axis played a role in regulating MDSC differentiation and apoptosis induced by SBRT. Modulating miR-21 levels in vivo impinged on the response to SBRT treatment and the quantity of MDSCs in a mouse model of lung cancer. CONCLUSION: Our data indicate that the upregulation of miR-21 induced by SBRT may contribute to the inhibition of MDSC expansion in a lung cancer model.