RESUMEN
The effects of low-dose radiation exposure remain a controversial topic in radiation biology. This study compares early (0.5, 4, 24, 48, and 72 h) and late (5, 10, and 15 cell passages) post-irradiation changes in γH2AX, 53BP1, pATM, and p-p53 (Ser-15) foci, proliferation, autophagy, and senescence in primary fibroblasts exposed to 100 and 2000 mGy X-ray radiation. The results show that exposure to 100 mGy significantly increased γH2AX, 53BP1, and pATM foci only at 0.5 and 4 h post irradiation. There were no changes in p-p53 (Ser-15) foci, proliferation, autophagy, or senescence up to 15 passages post irradiation at the low dose.
Asunto(s)
Autofagia , Proliferación Celular , Senescencia Celular , Reparación del ADN , Fibroblastos , Humanos , Fibroblastos/efectos de la radiación , Fibroblastos/metabolismo , Autofagia/efectos de la radiación , Senescencia Celular/efectos de la radiación , Reparación del ADN/efectos de la radiación , Rayos X/efectos adversos , Proliferación Celular/efectos de la radiación , Proteína 1 de Unión al Supresor Tumoral P53/metabolismo , Histonas/metabolismo , Relación Dosis-Respuesta en la Radiación , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Células Cultivadas , Daño del ADN/efectos de la radiaciónRESUMEN
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.
Asunto(s)
Apoptosis , Proliferación Celular , Rabdomiosarcoma , Ensayos Antitumor por Modelo de Xenoinjerto , Animales , Humanos , Ratones , Línea Celular Tumoral , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Proliferación Celular/efectos de los fármacos , Proliferación Celular/efectos de la radiación , Rabdomiosarcoma/radioterapia , Rabdomiosarcoma/tratamiento farmacológico , Rabdomiosarcoma/patología , Radiación Ionizante , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Modelos Animales de Enfermedad , Autofagia/efectos de los fármacos , Autofagia/efectos de la radiación , Terapia CombinadaRESUMEN
Hypoxia poses a significant challenge to the effectiveness of radiotherapy in head and neck squamous cell carcinoma (HNSCC) patients, and it is imperative to discover novel approaches to overcome this. In this study, we investigated the underlying mechanisms contributing to x-ray radioresistance in HPV-negative HNSCC cells under mild hypoxic conditions (1% oxygen) and explored the potential for autophagy modulation as a promising therapeutic strategy. Our findings show that HNSCC cells exposed to mild hypoxic conditions exhibit increased radioresistance, which is largely mediated by the hypoxia-inducible factor (HIF) pathway. We demonstrate that siRNA knockdown of HIF-1α and HIF-1ß leads to increased radiosensitivity in HNSCC cells under hypoxia. Hypoxia-induced radioresistance was not attributed to differences in DNA double strand break repair kinetics, as these remain largely unchanged under normoxic and hypoxic conditions. Rather, we identify autophagy as a critical protective mechanism in HNSCC cells following irradiation under mild hypoxia conditions. Targeting key autophagy genes, such as BECLIN1 and BNIP3/3L, using siRNA sensitizes these cells to irradiation. Whilst autophagy's role in hypoxic radioresistance remains controversial, this study highlights the importance of autophagy modulation as a potential therapeutic approach to enhance the effectiveness of radiotherapy in HNSCC.
Asunto(s)
Autofagia , Hipoxia de la Célula , Tolerancia a Radiación , Carcinoma de Células Escamosas de Cabeza y Cuello , Humanos , Autofagia/efectos de la radiación , Autofagia/genética , Tolerancia a Radiación/genética , Línea Celular Tumoral , Carcinoma de Células Escamosas de Cabeza y Cuello/radioterapia , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Hipoxia de la Célula/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Beclina-1/metabolismo , Beclina-1/genética , Neoplasias de Cabeza y Cuello/radioterapia , Neoplasias de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Reparación del ADN/efectos de la radiación , Reparación del ADN/genética , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas/genética , Rayos X , Roturas del ADN de Doble Cadena/efectos de la radiación , Proteínas Supresoras de TumorRESUMEN
BACKGROUND: Radiotherapy is a primary local treatment for tumors, yet it may lead to complications such as radiation-induced heart disease (RIHD). Currently, there is no standardized approach for preventing RIHD. Dexmedetomidine (Dex) is reported to have cardio-protection effects, while its role in radiation-induced myocardial injury is unknown. In the current study, we aimed to evaluate the radioprotective effect of dexmedetomidine in X-ray radiation-treated mice. METHODS: 18 male mice were randomized into 3 groups: control, 16 Gy, and 16 Gy + Dex. The 16 Gy group received a single dose of 16 Gy X-ray radiation. The 16 Gy + Dex group was pretreated with dexmedetomidine (30 µg/kg, intraperitoneal injection) 30 min before X-ray radiation. The control group was treated with saline and did not receive X-ray radiation. Myocardial tissues were collected 16 weeks after X-ray radiation. Hematoxylin-eosin staining was performed for histopathological examination. Terminal deoxynucleotidyl transferase dUTP nick-end labeling staining was performed to assess the state of apoptotic cells. Immunohistochemistry staining was performed to examine the expression of CD34 molecule and von Willebrand factor. Besides, western blot assay was employed for the detection of apoptosis-related proteins (BCL2 apoptosis regulator and BCL2-associated X) as well as autophagy-related proteins (microtubule-associated protein 1 light chain 3, beclin 1, and sequestosome 1). RESULTS: The findings demonstrated that 16 Gy X-ray radiation resulted in significant changes in myocardial tissues, increased myocardial apoptosis, and activated autophagy. Pretreatment with dexmedetomidine significantly protects mice against 16 Gy X-ray radiation-induced myocardial injury by inhibiting apoptosis and autophagy. CONCLUSION: In summary, our study confirmed the radioprotective effect of dexmedetomidine in mitigating cardiomyocyte apoptosis and autophagy induced by 16 Gy X-ray radiation.
Asunto(s)
Apoptosis , Autofagia , Dexmedetomidina , Miocitos Cardíacos , Traumatismos Experimentales por Radiación , Animales , Autofagia/efectos de los fármacos , Autofagia/efectos de la radiación , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/patología , Miocitos Cardíacos/efectos de la radiación , Miocitos Cardíacos/metabolismo , Apoptosis/efectos de los fármacos , Masculino , Dexmedetomidina/farmacología , Traumatismos Experimentales por Radiación/prevención & control , Traumatismos Experimentales por Radiación/patología , Traumatismos Experimentales por Radiación/metabolismo , Traumatismos Experimentales por Radiación/tratamiento farmacológico , Protectores contra Radiación/farmacología , Modelos Animales de Enfermedad , Transducción de Señal/efectos de los fármacos , Ratones , Proteínas Relacionadas con la Autofagia/metabolismo , Ratones Endogámicos C57BL , Proteínas Reguladoras de la Apoptosis/metabolismoRESUMEN
Autophagy participates in the regulation of ferroptosis. Among numerous autophagy-related genes (ATGs), ATG5 plays a pivotal role in ferroptosis. However, how ATG5-mediated ferroptosis functions in UVB-induced skin inflammation is still unclear. In this study, we unveil that the core ferroptosis inhibitor GPX4 is significantly decreased in human skin tissue exposed to sunlight. We report that ATG5 deletion in mouse keratinocytes strongly protects against UVB-induced keratinocyte ferroptosis and skin inflammation. Mechanistically, ATG5 promotes the autophagy-dependent degradation of GPX4 in UVB-exposed keratinocytes, which leads to UVB-induced keratinocyte ferroptosis. Furthermore, we find that IFN-γ secreted by ferroptotic keratinocytes facilitates the M1 polarization of macrophages, which results in the exacerbation of UVB-induced skin inflammation. Together, our data indicate that ATG5 exacerbates UVB-induced keratinocyte ferroptosis in the epidermis, which subsequently gives rise to the secretion of IFN-γ and M1 polarization. Our study provides novel evidence that targeting ATG5 may serve as a potential therapeutic strategy for the amelioration of UVB-caused skin damage.
Asunto(s)
Proteína 5 Relacionada con la Autofagia , Ferroptosis , Interferón gamma , Queratinocitos , Macrófagos , Rayos Ultravioleta , Queratinocitos/metabolismo , Queratinocitos/efectos de la radiación , Queratinocitos/citología , Proteína 5 Relacionada con la Autofagia/metabolismo , Proteína 5 Relacionada con la Autofagia/genética , Animales , Ratones , Interferón gamma/metabolismo , Macrófagos/metabolismo , Macrófagos/efectos de la radiación , Macrófagos/citología , Humanos , Piel/efectos de la radiación , Piel/metabolismo , Piel/patología , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Autofagia/efectos de la radiación , Inflamación/metabolismo , Inflamación/patologíaRESUMEN
This study was aimed to investigate the effect of hydrogen-rich solution (HRS) on acute radiation pneumonitis (ARP) in rats. The ARP model was induced by X-ray irradiation. Histopathological changes were assessed using HE and Masson stains. Inflammatory cytokines were detected by ELISA. Immunohistochemistry and flow cytometry were performed to quantify macrophage (CD68) levels and the M2/M1 ratio. Western blot analysis, RT-qPCR, ELISA and flow cytometry were used to evaluate mitochondrial oxidative stress injury indicators. Immunofluorescence double staining was performed to colocalize CD68/LC3B and p-AMPK-α/CD68. The relative expression of proteins associated with autophagy activation and the adenosine 5'-monophosphate-activated protein kinase/mammalian target of rapamycin/Unc-51-like kinase 1 (AMPK/mTOR/ULK1) signaling pathway were detected by western blotting. ARP decreased body weight, increased the lung coefficient, collagen deposition and macrophage infiltration and promoted M1 polarization in rats. After HRS treatment, pathological damage was alleviated, and M1 polarization was inhibited. Furthermore, HRS treatment reversed the ARP-induced high levels of mitochondrial oxidative stress injury and autophagy inhibition. Importantly, the phosphorylation of AMPK-α was inhibited, the phosphorylation of mTOR and ULK1 was activated in ARP rats and this effect was reversed by HRS treatment. HRS inhibited M1 polarization and alleviated oxidative stress to activate autophagy in ARP rats by regulating the AMPK/mTOR/ULK1 signaling pathway.
Asunto(s)
Autofagia , Hidrógeno , Macrófagos , Estrés Oxidativo , Neumonitis por Radiación , Ratas Sprague-Dawley , Animales , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/efectos de la radiación , Hidrógeno/farmacología , Hidrógeno/uso terapéutico , Autofagia/efectos de los fármacos , Autofagia/efectos de la radiación , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Macrófagos/efectos de la radiación , Neumonitis por Radiación/tratamiento farmacológico , Neumonitis por Radiación/patología , Neumonitis por Radiación/metabolismo , Masculino , Ratas , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Polaridad Celular/efectos de los fármacos , Polaridad Celular/efectos de la radiación , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/efectos de la radiación , Enfermedad AgudaRESUMEN
Endolysosomes perform a wide range of cellular functions, including nutrient sensing, macromolecule digestion and recycling, as well as plasma membrane repair. Because of their high activity in cancerous cells, endolysosomes are attractive targets for the development of novel cancer treatments. Light-activated compounds termed photosensitizers (PS) can catalyze the oxidation of specific biomolecules and intracellular organelles. To selectively damage endosomes and lysosomes, HT-29 colorectal cancer cells were incubated with nanomolar concentrations of meso-tetraphenylporphine disulfonate (TPPS2a), an amphiphilic PS taken up via endocytosis and activated by green light (522 nm, 2.1 J.cm-1). Several cellular responses were characterized by a combination of immunofluorescence and immunoblotting assays. We showed that TPPS2a photosensitization blocked autophagic flux without extensive endolysosomal membrane rupture. Nevertheless, there was a severe functional failure of endolysosomes due to a decrease in CTSD (cathepsin D, 55%) and CTSB (cathepsin B, 52%) maturation. PSAP (prosaposin) processing (into saposins) was also considerably impaired, a fact that could be detrimental to glycosphingolipid homeostasis. Therefore, photosensitization of HT-29 cells previously incubated with a low concentration of TPPS2a promotes endolysosomal dysfunction, an effect that can be used to improve cancer therapies.
Asunto(s)
Autofagia , Lisosomas , Fármacos Fotosensibilizantes , Humanos , Células HT29 , Lisosomas/metabolismo , Lisosomas/efectos de los fármacos , Autofagia/efectos de los fármacos , Autofagia/efectos de la radiación , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química , Endosomas/metabolismo , Endosomas/efectos de los fármacos , Catepsinas/metabolismo , Catepsinas/antagonistas & inhibidores , Luz , Porfirinas/farmacología , Porfirinas/química , Catepsina D/metabolismo , Catepsina B/metabolismoRESUMEN
BACKGROUND: Tumor-associated macrophages (TAMs) are intimately involved in cancer radiochemotherapy resistance. However, the mechanism by which macrophages affect radiosensitivity through autophagy remains unclear. The purpose of our study was to investigate how activating autophagy in type-II macrophages (M2) by using rapamycin (RAP) would affect the radiosensitivity of colorectal cancer (CRC) xenografts. MATERIALS AND METHODS: A nude mouse CRC model was established by injecting LoVo CRC cells. After tumor formation, supernatant from M2 cells (autophagy-unactivated), autophagy-activated M2 cells, or autophagy-downregulated M2 cells was injected peritumorally. All tumor-bearing mice were irradiated with 8-Gy X-rays twice, and the radiosensitivity of CRC xenografts was analyzed in each group. RESULTS: The mass, volume, and microvessel density (MVD) of tumors in the autophagy-unactivated M2 group significantly increased; however, supernatant from M2 cells that were autophagy-activated by rapamycin significantly decreased tumor weight, volume, and MVD compared with negative control. Combining bafilomycin A1 (BAF-A1) with RAP treatment restored the ability of the M2 supernatant to increase tumor mass, volume, and MVD. Immunohistochemical and Western blot results showed that compared with the negative control group, supernatant from M2 cells that were not activated by autophagy downregulated the expression of Livin and Survivin in tumor tissues; activation of M2 autophagy further downregulated the protein levels. CONCLUSIONS: Therefore, autophagy-activated M2 supernatant can downregulate the expression of the antiapoptotic genes Livin and Survivin in CRC xenografts, improving the radiosensitivity of CRC by inducing apoptosis in combination with radiotherapy and inhibiting the growth of transplanted tumors.
Asunto(s)
Autofagia , Neoplasias Colorrectales , Ratones Desnudos , Tolerancia a Radiación , Sirolimus , Ensayos Antitumor por Modelo de Xenoinjerto , Animales , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/terapia , Neoplasias Colorrectales/radioterapia , Neoplasias Colorrectales/metabolismo , Ratones , Autofagia/efectos de los fármacos , Autofagia/efectos de la radiación , Humanos , Tolerancia a Radiación/efectos de los fármacos , Sirolimus/farmacología , Sirolimus/uso terapéutico , Línea Celular Tumoral , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Macrófagos Asociados a Tumores/efectos de los fármacos , Macrófagos Asociados a Tumores/metabolismo , Macrófagos Asociados a Tumores/efectos de la radiación , Survivin/metabolismo , Survivin/genética , Ratones Endogámicos BALB C , MasculinoRESUMEN
Skin photoaging is mostly caused by ultraviolet A (UVA), although active medications to effectively counteract UVA-induced photoaging have not yet been created. Resveratrol, a naturally occurring polyphenol found in the skin of grapes, has been shown to have various biological functions such as anti-inflammatory and antioxidant characteristics. However, the role of resveratrol in UVA-induced photoaging has not been clarified. We investigated the mechanism of action of resveratrol by UVA irradiation of human skin fibroblasts (HSF) and innovatively modified a mouse model of photoaging. The results demonstrated that resveratrol promoted AMP-activated protein kinase (AMPK) phosphorylation to activate autophagy, reduce reactive oxygen species (ROS) production, inhibit apoptosis, and restore normal cell cycle to alleviate UVA-induced photoaging. In addition, subcutaneous injection of resveratrol not only improved the symptoms of roughness, erythema, and increased wrinkles in the skin of UVA photodamaged mice, but also alleviated epidermal hyperkeratosis and hyperpigmentation, reduced inflammatory responses, and inhibited collagen fiber degradation. In conclusion, our studies proved that resveratrol can treat UVA-induced photoaging and elucidated the possible molecular mechanisms involved, providing a new therapeutic strategy for future anti-aging.
Asunto(s)
Proteínas Quinasas Activadas por AMP , Autofagia , Fibroblastos , Resveratrol , Envejecimiento de la Piel , Piel , Rayos Ultravioleta , Resveratrol/farmacología , Envejecimiento de la Piel/efectos de los fármacos , Envejecimiento de la Piel/efectos de la radiación , Fibroblastos/efectos de los fármacos , Fibroblastos/efectos de la radiación , Fibroblastos/metabolismo , Autofagia/efectos de los fármacos , Autofagia/efectos de la radiación , Animales , Rayos Ultravioleta/efectos adversos , Humanos , Masculino , Proteínas Quinasas Activadas por AMP/metabolismo , Ratones , Piel/efectos de los fármacos , Piel/efectos de la radiación , Piel/patología , Piel/metabolismo , Estilbenos/farmacología , Transducción de Señal/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiaciónRESUMEN
Sunlight exposure results in an inflammatory reaction of the skin commonly known as sunburn, which increases skin cancer risk. In particular, the ultraviolet B (UVB) component of sunlight induces inflammasome activation in keratinocytes to instigate the cutaneous inflammatory responses. Here, we explore the intracellular machinery that maintains skin homeostasis by suppressing UVB-induced inflammasome activation in human keratinocytes. We found that pharmacological inhibition of autophagy promoted UVB-induced NLRP3 inflammasome activation. Unexpectedly, however, gene silencing of Atg5 or Atg7, which are critical for conventional autophagy, had no effect, whereas gene silencing of Beclin1, which is essential not only for conventional autophagy but also for Atg5/Atg7-independent alternative autophagy, promoted UVB-induced inflammasome activation, indicating an involvement of alternative autophagy. We found that damaged mitochondria were highly accumulated in UVB-irradiated keratinocytes when alternative autophagy was inhibited, and they appear to be recognized by NLRP3. Overall, our findings indicate that alternative autophagy, rather than conventional autophagy, suppresses UVB-induced NLRP3 inflammasome activation through the clearance of damaged mitochondria in human keratinocytes and illustrate a previously unknown involvement of alternative autophagy in inflammation. Alternative autophagy may be a new therapeutic target for sunburn and associated cutaneous disorders.
Asunto(s)
Autofagia , Inflamasomas , Queratinocitos , Mitocondrias , Proteína con Dominio Pirina 3 de la Familia NLR , Rayos Ultravioleta , Humanos , Autofagia/efectos de la radiación , Proteína 5 Relacionada con la Autofagia/metabolismo , Proteína 5 Relacionada con la Autofagia/genética , Proteína 7 Relacionada con la Autofagia/genética , Proteína 7 Relacionada con la Autofagia/metabolismo , Beclina-1/metabolismo , Beclina-1/genética , Inflamasomas/metabolismo , Queratinocitos/metabolismo , Queratinocitos/patología , Queratinocitos/efectos de la radiación , Mitocondrias/metabolismo , Mitocondrias/efectos de la radiación , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Rayos Ultravioleta/efectos adversos , Células CultivadasRESUMEN
Osteoporotic osteoarthritis (OPOA) is a specific phenotype of OA with high incidence and severe cartilage damage. This study aimed to explore the protective efficacy of PEMF on the progression of OPOA and observed the effects of PEMF on PPARγ, autophagy- and apoptosis-related proteins in OPOA rats. Rats were randomly divided into three groups: control group, OPOA group, and PEMF group (n = 6). One week after surgery, the rats in PEMF group were subjected to PEMF (3.82 mT, 8 Hz, 40 min/day and 5 day/week) for 12 weeks. Results showed that PEMF retarded cartilage degeneration and bone loss, as evidenced by pathological staining image, decreased MMP-13 expression and increased bone mineral density. PEMF inhibited the serum levels of inflammatory cytokines, and the expressions of caspase-3 and caspase-8, while upregulated the expression of PPARγ. Moreover, PEMF significantly improved the autophagy disorders, represented by decrease expressions of Beclin-1, P62, and LC3B. The research demonstrates that PEMF can effectively prevent cartilage and subchondral bone destruction in OPOA rats. The potential mechanism may be related to upregulation of PPARγ, inhibition of chondrocyte apoptosis and inflammation, and improvement of autophagy disorder. PEMF therapy thus shows promising application prospects in the treatment of postmenopausal OA.
Osteoporotic osteoarthritis (OPOA) is a very common combination disease, that characterized by chronic pain, swollen joints and susceptibility to fractures. It is particularly common in postmenopausal women. At present, drug therapy is the main treatment method, but the adverse reactions are serious and can not stop the progression of the disease. PEMF is a safe physical therapy that has been shown to increase bone density, reduce pain, and improve joints mobility. In this study, we aimed to explore the protective effect and potential mechanism of PEMF on OPOA. We found that PEMF significantly inhibited the inflammatory response, ameliorated the damaged cartilage and subchondral bone in OPOA rats, that maybe related to the regulation of chondrocyte autophagy and apoptosis. This study provided a new vision for PEMF' treatment on OPOA and has positive significance for the clinical promotion of PEMF.
Asunto(s)
Apoptosis , Autofagia , Modelos Animales de Enfermedad , Osteoartritis , PPAR gamma , Ratas Sprague-Dawley , Animales , Autofagia/efectos de la radiación , PPAR gamma/metabolismo , Apoptosis/efectos de la radiación , Ratas , Osteoartritis/terapia , Osteoartritis/patología , Osteoartritis/metabolismo , Femenino , Magnetoterapia , Osteoporosis/terapia , Osteoporosis/metabolismo , Osteoporosis/patologíaRESUMEN
This study was carried out to determine the effect of autophagy modulation in radiation treatment of cervical cancer cells. HeLa and CaSki cells were irradiated with γ-rays (2 Gy/min) after treatment with an autophagy inducer (rapamycin) and inhibitor (3-MA). Expression of LC3 and cell death in two cell preparations were examined. In addition, expression of Caspase-3 and PARP were examined after radiation alone and with autophagy inhibitor treatment. A notable increment of LC3 expression was detected after radiation in both cell lines. Cell viability was observed to decrease in 3-MA-treated cells compared to radiation alone, and even further in rapamycin-treated cells. Apoptosis was confirmed to occur later than autophagy in radiation treatment, and inhibition of autophagy derived a decrease in apoptosis. In conclusion, radiation-induced autophagy may be regulated by modulators, and autophagy augmentation yields an increase in cervical cancer cell death under radiation.Impact statementWhat is already known on this subject? Autophagy is known to contribute both to tumour cell survival and death against radiation therapy. The effect of induction or inhibition of radiation-induced autophagy on cervical cancer cell death is not clear.What the results of this study add? Cell viability was observed to decrease in 3-MA-treated cells compared to radiation alone, and even further in rapamycin-treated cells. Apoptosis occurred later than autophagy in radiation treatment, and inhibition of autophagy derived a decrease in apoptosis.What the implications are of these findings for clinical practice and/or further research? Our results suggest that radiation-induced autophagy may be regulated by modulators, and autophagy augmentation yields an increase in cervical cancer cell death under radiation.
Asunto(s)
Neoplasias del Cuello Uterino , Femenino , Humanos , Neoplasias del Cuello Uterino/radioterapia , Línea Celular Tumoral , Apoptosis , Autofagia/fisiología , Autofagia/efectos de la radiación , Sirolimus/farmacologíaRESUMEN
Despite advances in the development of tumor treatments, mortality from cancer continues to increase. Nanotechnology is expected to provide an innovative anti-cancer therapy, to combat challenges such as multidrug resistance and tumor recurrence. Nevertheless, tumors can greatly rely on autophagy as an alternative source for metabolites, and which desensitizes cancer cells to therapeutic stress, hindering the success of any current treatment paradigm. Autophagy is a conserved process by which cells turn over their own constituents to maintain cellular homeostasis. The multistep autophagic pathway provides potentially druggable targets to inhibit pro-survival autophagy under various therapeutic stimuli. In this review, we focus on autophagy inhibition based on functional nanoplatforms, which may be a potential strategy to increase therapeutic sensitivity in combinational cancer therapies, including chemotherapy, radiotherapy, phototherapy, sonodynamic therapy, and immunotherapy.
Asunto(s)
Autofagia , Neoplasias/terapia , Antineoplásicos/uso terapéutico , Autofagia/efectos de los fármacos , Autofagia/efectos de la radiación , Terapia Combinada , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de la radiación , Humanos , NanopartículasRESUMEN
Pancreatic cancer (PC) is highly resistant to chemo and radiotherapy. Radiation-induced fibrosis (RIF) is a major cause of clinical concern for various malignancies, including PC. In this study, we aimed to evaluate the radiosensitizing and anti-RIF potential of fluvastatin in PC. Short-term viability and clonogenic survival assays were used to evaluate the radiosensitizing potential of fluvastatin in multiple human and murine PC cell lines. The expression of different proteins was analyzed to understand the mechanisms of fluvastatin-mediated radiosensitization of PC cells and its anti-RIF effects in both mouse and human pancreatic stellate cells (PSCs). Finally, these effects of fluvastatin and/or radiation were assessed in an immune-competent syngeneic murine model of PC. Fluvastatin radiosensitized multiple PC cell lines, as well as radioresistant cell lines in vitro, by inhibiting radiation-induced DNA damage repair response. Nonmalignant cells, such as PSCs and NIH3T3 cells, were less sensitive to fluvastatin-mediated radiosensitization than PC cells. Interestingly, fluvastatin suppressed radiation and/or TGF-ß-induced activation of PSCs, as well as the fibrogenic properties of these cells in vitro. Fluvastatin considerably augmented the antitumor effect of external radiation therapy and also suppressed intra-tumor RIF in vivo. These findings suggested that along with radiation, fluvastatin co-treatment may be a potential therapeutic approach against PC.
Asunto(s)
Fluvastatina/farmacología , Neoplasias Pancreáticas/patología , Tolerancia a Radiación/efectos de los fármacos , Factor de Crecimiento Transformador beta/farmacología , Animales , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Autofagia/efectos de los fármacos , Autofagia/efectos de la radiación , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Células Cultivadas , Embrión no Mamífero/efectos de los fármacos , Embrión no Mamífero/embriología , Embrión no Mamífero/efectos de la radiación , Fibrosis/prevención & control , Humanos , Ratones , Ratones Endogámicos C57BL , Células 3T3 NIH , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/patología , Neoplasias Experimentales/radioterapia , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/radioterapia , Pez Cebra/embriologíaRESUMEN
Despite aggressive treatments, pancreatic ductal adenocarcinoma (PDAC) remains an intractable disease, largely because it is refractory to therapeutic interventions. To overcome its nutrient-poor microenvironment, PDAC heavily relies on autophagy for metabolic needs to promote tumor growth and survival. Here, we explore autophagy inhibition as a method to enhance the effects of radiotherapy on PDAC tumors. Hydroxychloroquine is an autophagy inhibitor at the focus of many PDAC clinical trials, including in combination with radiotherapy. However, its acid-labile properties likely reduce its intratumoral efficacy. Here, we demonstrate that EAD1, a synthesized analogue of HCQ, is a more effective therapeutic for sensitizing PDAC tumors of various KRAS mutations to radiotherapy. Specifically, in vitro models show that EAD1 is an effective inhibitor of autophagic flux in PDAC cells, accompanied by a potent inhibition of proliferation. When combined with radiotherapy, EAD1 is consistently superior to HCQ not only as a single agent, but also in radiosensitizing PDAC cells, and perhaps most importantly, in decreasing the self-renewal capacity of PDAC cancer stem cells (PCSC). The more pronounced sensitizing effects of autophagy inhibitors on pancreatic stem over differentiated cells points to a new understanding that PCSCs may be more dependent on autophagy to counter the effects of radiation toxicity, a potential mechanism explaining the resistance of PCSCs to radiotherapy. Finally, in vivo subcutaneous tumor models demonstrate that combination of radiotherapy and EAD1 is the most successful at controlling tumor growth. The models also confirmed a similar toxicity profile between EAD1 and Hydroxychloroquine.
Asunto(s)
Autofagia/genética , Autofagia/efectos de la radiación , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/radioterapia , Fármacos Sensibilizantes a Radiaciones/uso terapéutico , Animales , Humanos , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Fármacos Sensibilizantes a Radiaciones/farmacología , Análisis de Supervivencia , Neoplasias PancreáticasRESUMEN
Population aging is occurring rapidly worldwide, challenging the global economy and healthcare services. Brain aging is a significant contributor to various age-related neurological and neuropsychological disorders, including Alzheimer's disease and Parkinson's disease. Several extrinsic factors, such as exposure to ionizing radiation, can accelerate senescence. Multiple human and animal studies have reported that exposure to ionizing radiation can have varied effects on organ aging and lead to the prolongation or shortening of life span depending on the radiation dose or dose rate. This paper reviews the effects of radiation on the aging of different types of brain cells, including neurons, microglia, astrocytes, and cerebral endothelial cells. Further, the relevant molecular mechanisms are discussed. Overall, this review highlights how radiation-induced senescence in different cell types may lead to brain aging, which could result in the development of various neurological and neuropsychological disorders. Therefore, treatment targeting radiation-induced oxidative stress and neuroinflammation may prevent radiation-induced brain aging and the neurological and neuropsychological disorders it may cause.
Asunto(s)
Encéfalo/patología , Senescencia Celular/efectos de la radiación , Radiación Ionizante , Animales , Autofagia/efectos de la radiación , Humanos , Mitocondrias/patología , Mitocondrias/efectos de la radiación , Estrés Oxidativo/efectos de la radiaciónRESUMEN
Autophagy is involved in the degradation of melanosomes and the determination of skin color. TLR4 and tumor necrosis factor (TNF) signaling upregulates NF-kB expression, which is involved in the upregulation of mTOR. The activation of mTOR by UV-B exposure results in decreased autophagy, whereas radiofrequency (RF) irradiation decreases TLR4 and TNF receptor (TNFR) expression. We evaluated whether RF decreased skin pigmentation by restoring autophagy by decreasing the expression of TLR4 or TNFR/NF-κB/mTOR in the UV-B-irradiated animal model. UV-B radiation induced the expressions of TNFR, TLR, and NF-κB in the skin, which were all decreased by RF irradiation. RF irradiation also decreased phosphorylated mTOR expression and upregulated autophagy initiation factors such as FIP200, ULK1, ULK2, ATG13, and ATG101 in the UV-B-irradiated skin. Beclin 1 expression and the expression ratio of LC3-I to LC3-II were increased by UV-B/RF irradiation. Furthermore, melanin-containing autophagosomes increased with RF irradiation. Fontana-Masson staining showed that the amount of melanin deposition in the skin was decreased by RF irradiation. This study showed that RF irradiation decreased skin pigmentation by restoring melanosomal autophagy, and that the possible signal pathways which modulate autophagy could be TLR4, TNFR, NF-κB, and mTOR.
Asunto(s)
Autofagia/efectos de la radiación , Melaninas/biosíntesis , Melanosomas/metabolismo , Ondas de Radio , Pigmentación de la Piel/efectos de la radiación , Rayos Ultravioleta , Biomarcadores , Células Cultivadas , Regulación de la Expresión Génica/efectos de la radiación , Humanos , Inmunohistoquímica , FN-kappa B/metabolismo , Receptores del Factor de Necrosis Tumoral/genética , Receptores del Factor de Necrosis Tumoral/metabolismo , Pigmentación de la Piel/genética , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Receptor Toll-Like 4/metabolismoRESUMEN
Radiation damages many cellular components and disrupts cellular functions, and was previously reported to impair locomotion in the model organism Caenorhabditis elegans. However, the response to even higher doses is not clear. First, to investigate the effects of high-dose radiation on the locomotion of C. elegans, we investigated the dose range that reduces whole-body locomotion or leads to death. Irradiation was performed in the range of 0-6 kGy. In the crawling analysis, motility decreased after irradiation in a dose-dependent manner. Exposure to 6 kGy of radiation affected crawling on agar immediately and caused the complete loss of motility. Both γ-rays and carbon-ion beams significantly reduced crawling motility at 3 kGy. Next, swimming in buffer was measured as a motility index to assess the response over time after irradiation and motility similarly decreased. However, swimming partially recovered 6 h after irradiation with 3 kGy of γ-rays. To examine the possibility of a recovery mechanism, in situ GFP reporter assay of the autophagy-related gene lgg-1 was performed. The fluorescence intensity was stronger in the anterior half of the body 7 h after irradiation with 3 kGy of γ-rays. GFP::LGG-1 induction was observed in the pharynx, neurons along the body, and the intestine. Furthermore, worms were exposed to region-specific radiation with carbon-ion microbeams and the trajectory of crawling was measured by image processing. Motility was lower after anterior-half body irradiation than after posterior-half body irradiation. This further supported that the anterior half of the body is important in the locomotory response to radiation.
Asunto(s)
Autofagia/efectos de la radiación , Locomoción/efectos de la radiación , Dosis de Radiación , Animales , Autofagia/fisiología , Caenorhabditis elegans/fisiología , Caenorhabditis elegans/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Rayos gamma/efectos adversos , Humanos , Locomoción/fisiología , Irradiación Corporal Total/efectos adversosRESUMEN
The expanding clinical application of CDK4- and CDK6-inhibiting drugs in the managements of breast cancer has raised a great interest in testing these drugs in other neoplasms. The potential of combining these drugs with other therapeutic approaches seems to be an interesting work-ground to explore. Even though a potential integration of CDK4 and CDK6 inhibitors with radiotherapy (RT) has been hypothesized, this kind of approach has not been sufficiently pursued, neither in preclinical nor in clinical studies. Similarly, the most recent discoveries focusing on autophagy, as a possible target pathway able to enhance the antitumor efficacy of CDK4 and CDK6 inhibitors is promising but needs more investigations. The aim of this review is to discuss the recent literature on the field in order to infer a rational combination strategy including cyclin-D1/CDK4-CDK6 inhibitors, RT, and/or other anticancer agents targeting G1-S phase cell cycle transition.
Asunto(s)
Antineoplásicos/uso terapéutico , Quinasa 4 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 6 Dependiente de la Ciclina/antagonistas & inhibidores , Neoplasias/tratamiento farmacológico , Neoplasias/radioterapia , Inhibidores de Proteínas Quinasas/uso terapéutico , Animales , Antineoplásicos/farmacología , Autofagia/efectos de los fármacos , Autofagia/efectos de la radiación , Ciclo Celular/efectos de los fármacos , Ciclo Celular/efectos de la radiación , Quimioradioterapia , Ciclina D1/antagonistas & inhibidores , Ciclina D1/metabolismo , Quinasa 4 Dependiente de la Ciclina/metabolismo , Quinasa 6 Dependiente de la Ciclina/metabolismo , Humanos , Neoplasias/metabolismo , Inhibidores de Proteínas Quinasas/farmacologíaRESUMEN
Age-related macular degeneration (AMD) causes the degeneration of photoreceptors and retinal cells leading to vision loss in older subjects. Among possible exogenous risk factors, it has been recently proposed that long-term exposure to blue light could aggravate the course of AMD. In the search for therapeutic options, plasma rich in growth factors (PRGF) has been shown to enhance cell antioxidant pathways and protect photoreceptors against the harm produced by blue light, although its mechanism of action remains unknown. One possible mechanism, autophagy, is one of the most conservative cell renewal systems used in eukaryotes to destroy cellular components that have been damaged by some kind of insult. The oxidative stress of exposure to blue light is known to induce cell autophagy. In this study, we examined the combined effects on autophagy of blue light and PRGF in a retinal cell line, ARPE19. In response to treatment with both PRGF and blue light, we detected the modulated expression of autophagy markers such as NF-kB, p62/sqstm1, Atg5, LC3 and Beclin1, and inflammatory markers such as IL1B and IL18. Our findings suggest that PRGF promotes cell autophagy in response to exposure to blue light.