Photochemistry and Photobiology最新文献_第3页

Evaluating photodynamic therapy response in head and neck cancer with EGFR-targeted paired-agent imaging. 用egfr靶向配对显像评价头颈癌的光动力治疗反应。

IF 2.6 4区生物学

Photochemistry and Photobiology Pub Date : 2026-09-01 Epub Date: 2026-02-06 DOI: 10.1111/php.70076

Reeham Choudhury, Sanjana Pannem, Yichen Feng, Sassan Hodge, Kimberley S Samkoe

{"title":"Evaluating photodynamic therapy response in head and neck cancer with EGFR-targeted paired-agent imaging.","authors":"Reeham Choudhury, Sanjana Pannem, Yichen Feng, Sassan Hodge, Kimberley S Samkoe","doi":"10.1111/php.70076","DOIUrl":"10.1111/php.70076","url":null,"abstract":"Head and neck cancer (HNC) affects thousands globally, with high morbidity rates due to standard treatments like surgery and radiation. Photodynamic therapy (PDT) has shown great promise as a less destructive alternative, selectively targeting tumors while preserving healthy tissue. However, assessing treatment response in the days after PDT is challenging due to significant inflammation and the subsequent vascular shutdown of the tumor. We hypothesize that fluorescence paired-agent imaging (PAI) can provide early molecular insights within 24 h of PDT to evaluate treatment efficacy. PAI utilizes two fluorescent agents to correct for perfusion-related changes, allowing for accurate quantification of key signaling proteins. Specifically, we tracked epidermal growth factor receptor (EGFR) response to benzoporphyrin derivative monoacid (BPD)-PDT at 690 nm, with light fluences ranging from 0 to 100 J/cm2. Twenty-four hours post-PDT, EGFR concentrations were measured using PAI with ABY-029 and IRDye 680LT as targeted and untargeted agents, respectively. These findings were compared to histopathology (H&E and EGFR IHC). Our histological results demonstrated that EGFR expression increased with low PDT doses (10 and 25 J/cm2) and decreased below baseline expression with higher doses (50 and 100 J/cm2). Fluorescence intensity of both ABY-029 and IRDye 680LT was highly variable with treatment dose and was not correlative to tumor response. In contrast, the PAI-binding potential (BP) corresponded to the varying EGFR expression measured by pathology. In vivo and ex vivo PAI BP was moderately to highly correlative to percent area IHC EGFR expression (r = 0.65 and 0.54, p < 0.05, respectively) and the in vivo 100 J/cm2 treatment group demonstrated significantly lower BP than the controls. PAI emerges as a promising tool for tracking early molecular changes in HNC, with potential clinical applications.","PeriodicalId":20133,"journal":{"name":"Photochemistry and Photobiology","volume":" ","pages":"1274-1284"},"PeriodicalIF":2.6,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13575706/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146133174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Measurement and modeling of diffuse ultraviolet radiation: A review. 漫射紫外线辐射的测量和建模：综述。

IF 2.6 4区生物学

Photochemistry and Photobiology Pub Date : 2026-09-01 Epub Date: 2026-03-02 DOI: 10.1111/php.70084

Alfio V Parisi, Joanna Turner, Abdurazaq Amar, Damien P Igoe, Peter Schouten, Nawin Raj, Nathan Downs, Harry Butler

{"title":"Measurement and modeling of diffuse ultraviolet radiation: A review.","authors":"Alfio V Parisi, Joanna Turner, Abdurazaq Amar, Damien P Igoe, Peter Schouten, Nawin Raj, Nathan Downs, Harry Butler","doi":"10.1111/php.70084","DOIUrl":"10.1111/php.70084","url":null,"abstract":"The ultraviolet (UV) radiation environment consists of direct UV and diffuse UV components. The ratios of diffuse-to-direct UV for the UVB, UVA, and the erythema UV wavebands are influenced by clouds, aerosols, albedo, and surface reflectance, Rayleigh scattering, and solar zenith angle. At times, the relative proportion of diffuse UV may be higher than the direct UV, for example, on cloudy days or days with high atmospheric aerosols. Consequently, exposures due to diffuse UV radiation play a significant role in the UV exposure received by human subjects. Diffuse UV radiation contributes to the risk of skin cancer and sun-related eye disorders. Reducing personal exposure to diffuse UV by physical protection, including tree shade, purpose-built shade structures, protection by hats, and eyewear, is more difficult than reducing direct UV exposure due to the diffuse UV being incident from all directions. The UV index reported to the public represents the sum of the direct and the diffuse erythema UV, with no information provided specifically on the diffuse UV component. This paper reviews the factors that contribute to diffuse UV exposures affecting human populations. It examines diffuse UV modeling techniques, and broadband and spectral component measurements.","PeriodicalId":20133,"journal":{"name":"Photochemistry and Photobiology","volume":" ","pages":"1048-1059"},"PeriodicalIF":2.6,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13575707/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147344791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spectral characterization of three wearable electronic ultraviolet radiation dosimeters. 三种可穿戴电子紫外辐射剂量计的光谱特性。

IF 2.6 4区生物学

Photochemistry and Photobiology Pub Date : 2026-09-01 Epub Date: 2026-03-06 DOI: 10.1111/php.70085

Leevi August, Gregor Hülsen, Juha Peltoniemi, Petri Kärhä, Erkki Ikonen

{"title":"Spectral characterization of three wearable electronic ultraviolet radiation dosimeters.","authors":"Leevi August, Gregor Hülsen, Juha Peltoniemi, Petri Kärhä, Erkki Ikonen","doi":"10.1111/php.70085","DOIUrl":"10.1111/php.70085","url":null,"abstract":"Excessive exposure to ultraviolet (UV) radiation poses significant public health risks, including DNA damage and skin-related pathologies. This necessitates accurate studies and quantification of UV-radiation exposure. Various wearable UV dosimeters have been developed to address these needs, particularly for outdoor workers. For measuring erythemal irradiance, recommendations from the World Meteorological Organization exist but standardized methods for characterization and calibration of wearable UV dosimeters are currently limited. At Aalto University and at Physikalisch-Meteorologisches Observatorium Davos, three commercial electronic UV dosimeters were evaluated for their spectral responsivities using conventional measurement methods and traceability chains. The first device closely mimicked erythemal action in UV-A and UV-B regions. Two of the measured devices were found to have a higher relative responsivity of over 0.9 in the 300 nm to 310 nm range. Results were used to calculate correction factors for measuring erythemal radiance at varying solar zenith angles and ozone levels under cloud-free conditions. Typical correction factors ranged from 0.98 to 1.2. The results of the two laboratories were in good agreement for the most accurate device but deviated due to the properties of the two other devices. The measurements revealed challenges posed by these devices in terms of data management, measurement times, and deployment, highlighting the need for standardized characterization methods.","PeriodicalId":20133,"journal":{"name":"Photochemistry and Photobiology","volume":" ","pages":"1112-1122"},"PeriodicalIF":2.6,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13575695/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147366536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluating tools for predicting and measuring radiometric performance of germicidal ultraviolet systems. 预测和测量杀菌紫外系统辐射性能的评估工具。

IF 2.6 4区生物学

Photochemistry and Photobiology Pub Date : 2026-09-01 Epub Date: 2026-02-18 DOI: 10.1111/php.70080

Valeria Holland, Belal Abboushi, Eduardo Rodriguez-Feo Bermudez, Jason Tuenge, Annabelle Johnson, Shohoria Shorno, Ernest R Blatchley, Gabe Arnold

{"title":"Evaluating tools for predicting and measuring radiometric performance of germicidal ultraviolet systems.","authors":"Valeria Holland, Belal Abboushi, Eduardo Rodriguez-Feo Bermudez, Jason Tuenge, Annabelle Johnson, Shohoria Shorno, Ernest R Blatchley, Gabe Arnold","doi":"10.1111/php.70080","DOIUrl":"10.1111/php.70080","url":null,"abstract":"Germicidal ultraviolet (GUV) air treatment technologies can be effective and safe for reducing airborne disease transmission. Today, GUV systems are designed and evaluated using simulation and measurement tools that require further assessment of their accuracy in estimating fluence rate and irradiance. This article reports results from two experiments where two simulation software (Visual Lighting and Photopia) and two measurement techniques (tetrahedron and cubic approximations) were evaluated against chemical actinometry for quantification of GUV fluence rate in a chamber. Additionally, Visual and Photopia were compared to measurements of planar UV-C irradiance for eye and skin exposure. Results showed that overall mean fluence rates were similar between actinometry and both simulation software for WR GUV systems as well as between actinometry and Photopia for UR GUV systems. The tetrahedron approximation better predicted overall mean fluence rate for WR and UR GUV systems, compared to a cubic approximation which tended to overestimate it. Compared to measurements, simulated eye and skin irradiance varied, with higher variability in simulated eye irradiance. The evaluated simulation software can be used to guide the design of GUV systems but must be supplemented with in situ measurements.","PeriodicalId":20133,"journal":{"name":"Photochemistry and Photobiology","volume":" ","pages":"1123-1137"},"PeriodicalIF":2.6,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13575708/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146220768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Chlorophyll-based sustainable and eco-friendly optical sensor for efficient detection of pyrene. 基于叶绿素的可持续环保光学传感器，用于高效检测芘。

IF 2.6 4区生物学

Photochemistry and Photobiology Pub Date : 2026-09-01 Epub Date: 2025-12-30 DOI: 10.1111/php.70066

Siddhartha Protim Bharadwaj, Purabi Gogoi, Roshmi Pangyok, Chayanika Chetia, Mondeep Gohain, Pankaj Dutta

{"title":"Chlorophyll-based sustainable and eco-friendly optical sensor for efficient detection of pyrene.","authors":"Siddhartha Protim Bharadwaj, Purabi Gogoi, Roshmi Pangyok, Chayanika Chetia, Mondeep Gohain, Pankaj Dutta","doi":"10.1111/php.70066","DOIUrl":"10.1111/php.70066","url":null,"abstract":"In this study, a highly sensitive, cost-effective, and environmentally friendly fluorescent sensing platform is presented for the rapid detection of pyrene (PYR), a polycyclic aromatic hydrocarbon (PAH), by leveraging the optical properties of the plant pigment chlorophyll (Chl). The detection mechanism relies on monitoring changes in Chl's photoluminescence (PL) intensity, fluorescence lifetime, and Fourier-transform infrared spectra. An impressive detection limit of 0.25 picomolar was achieved, surpassing the sensitivity reported in many previous studies. Fluorescence resonance energy transfer (FRET) was identified as the primary mechanism underlying the observed sensing response. The platform's effectiveness was further validated using soil and water sediment samples collected from oil exploration sites, demonstrating reliable quantification of PYR. This research underscores the potential of Chl-based fluorescence as a sustainable and efficient tool for a wide range of sensing applications, particularly in environmental monitoring.","PeriodicalId":20133,"journal":{"name":"Photochemistry and Photobiology","volume":" ","pages":"1285-1302"},"PeriodicalIF":2.6,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13575710/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145857511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effects of solar-simulated (UVB plus UVA) radiation on the skin microbiome: An exploratory study. 太阳模拟（UVB + UVA）辐射对皮肤微生物组的影响：一项探索性研究。

IF 2.6 4区生物学

Photochemistry and Photobiology Pub Date : 2026-09-01 Epub Date: 2026-01-29 DOI: 10.1111/php.70078

Florian Dimmers, Doreen Reichert, Claudia Wigmann, Carles Trullàs, Jaime Piquero-Casals, Anthony Brown, Monica Foyaca, Charlotte Esser, Jean Krutmann

{"title":"Effects of solar-simulated (UVB plus UVA) radiation on the skin microbiome: An exploratory study.","authors":"Florian Dimmers, Doreen Reichert, Claudia Wigmann, Carles Trullàs, Jaime Piquero-Casals, Anthony Brown, Monica Foyaca, Charlotte Esser, Jean Krutmann","doi":"10.1111/php.70078","DOIUrl":"10.1111/php.70078","url":null,"abstract":"This exploratory in vivo study investigated the impact of solar-simulated ultraviolet (UV) radiation (UVB plus UVA) on the composition of the human skin microbiome in healthy male volunteers. Thirty Caucasian men were exposed to suberythemal and erythemal doses of UV radiation (0.5, 0.7, and 1.0 minimal erythema dose, MED) on defined areas of the lower back. Skin swabs were collected from both irradiated (n = 243) and nonirradiated control sites (n = 81) 30 min, 24 h, and 96 h postexposure. The microbial profiles were generated using flow cytometry, and the data were analyzed via the open-access bioinformatic platform FlowSoFine™. The results revealed pronounced alterations in the microbial composition, with changes already detectable 30 min after exposure. Although partial recovery was observed over time, certain microbial shifts persisted. Further analysis indicated dose-dependent trends in microbiome changes, suggesting a potential relationship between the extent of microbial alteration and the applied UV dose. These results suggest that even low, nonerythematous exposure to solar-simulated UV radiation can rapidly alter the microbial balance of the skin and emphasize the role of UV radiation as a potent modulator of the skin microbial homeostasis.","PeriodicalId":20133,"journal":{"name":"Photochemistry and Photobiology","volume":" ","pages":"1150-1158"},"PeriodicalIF":2.6,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13575714/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146086580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effects of photobiomodulation with 450 nm and 635 nm laser wavelengths on the release of TGF-β, BMP-2, FGF-2, and VEGF from dental pulp stem cells. 450 nm和635 nm激光波长光生物调节对牙髓干细胞TGF-β、BMP-2、FGF-2和VEGF释放的影响

IF 2.6 4区生物学

Photochemistry and Photobiology Pub Date : 2026-09-01 Epub Date: 2026-01-26 DOI: 10.1111/php.70073

Mahsa Sadeghi, Kiumars Nazarimoghadam, Hossein Labbaf, Zahra Jafari, Nasim Chiniforush

{"title":"Effects of photobiomodulation with 450 nm and 635 nm laser wavelengths on the release of TGF-β, BMP-2, FGF-2, and VEGF from dental pulp stem cells.","authors":"Mahsa Sadeghi, Kiumars Nazarimoghadam, Hossein Labbaf, Zahra Jafari, Nasim Chiniforush","doi":"10.1111/php.70073","DOIUrl":"10.1111/php.70073","url":null,"abstract":"This study assessed the effects of photobiomodulation with 450 and 635 nm laser wavelengths on the release of transforming growth factor-beta (TGF-β), bone morphogenetic protein (BMP)-2, fibroblast growth factor (FGF)-2, and vascular endothelial growth factor (VEGF) from human dental pulp stem cells (DPSCs). In this in vitro study, human DPSCs were cultured and randomly assigned to two experimental groups to undergo 450 and 635 nm laser irradiation with 2, 4, and 6 J/cm2 energy densities, and one control group (n = 5). After laser irradiation, total RNA was then extracted, cDNA was synthesized, and expression of TGF-β, FGF-2, BMP-2, and VEGF was assessed by real-time polymerase chain reaction (PCR). Data were analyzed by one-way and two-way ANOVA and Tukey's test (alpha = 0.05). The effects of laser wavelength, energy density, and their interaction were significant on the release of all growth factors (p < 0.0001). Laser irradiation in almost all subgroups increased the release of growth factors. By an increase in energy density, the release of BMP-2 and FGF-2 in both wavelengths, VEGF in the 635 nm group, and TGF-β in the 635 nm group increased while the release of VEGF in the 450 nm group decreased (p < 0.05). The amount of released growth factors in the 635 nm group was higher than in the 450 nm group (p < 0.05). PBMT with 450 and 635 nm lasers increased the release of TGF-β, BMP-2, FGF-2, and VEGF from human DPSCs in most energy densities, which may be of use in regenerative endodontics.","PeriodicalId":20133,"journal":{"name":"Photochemistry and Photobiology","volume":" ","pages":"1248-1258"},"PeriodicalIF":2.6,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13575701/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146053400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Photocatalytic reduction of nitro compounds using TiO₂-NaAsc-NC (LMCT/EDA) complex system in water under visible blue and green LED irradiation. TiO2-NaAsc-NC （LMCT/EDA）复合体系在可见光蓝绿LED照射下光催化还原水中硝基化合物

IF 2.6 4区生物学

Photochemistry and Photobiology Pub Date : 2026-09-01 Epub Date: 2026-01-02 DOI: 10.1111/php.70062

Ayub Ahmadi, Hadi Yari, Yadollah Shariati, Milad Taghizadeh, Foad Kazemi, Babak Kaboudin

引用次数: 0

Characterization and parameters for the effectiveness of a UV-C device for infection control in dental clinics. 一种用于牙科诊所感染控制的UV-C装置的特性和有效性参数。

IF 2.6 4区生物学

Photochemistry and Photobiology Pub Date : 2026-09-01 Epub Date: 2026-01-18 DOI: 10.1111/php.70065

Kátia Cristiane Hall, Everton Granemann Souza, Chiara das Dores do Nascimento, Marcel Luiz Basso, Mário Lúcio Moreira, Carla Lucía David Pena, Wellington Luiz Oliveira da Rosa, Rafael Guerra Lund, Evandro Piva

{"title":"Characterization and parameters for the effectiveness of a UV-C device for infection control in dental clinics.","authors":"Kátia Cristiane Hall, Everton Granemann Souza, Chiara das Dores do Nascimento, Marcel Luiz Basso, Mário Lúcio Moreira, Carla Lucía David Pena, Wellington Luiz Oliveira da Rosa, Rafael Guerra Lund, Evandro Piva","doi":"10.1111/php.70065","DOIUrl":"10.1111/php.70065","url":null,"abstract":"Healthcare-associated infections (HAIs) remain a significant concern in dental settings, especially in light of increasing antimicrobial resistance. This study aimed to characterize and evaluate the efficacy of an ultraviolet C (UV-C) disinfection device specifically developed as an additional resource for dental clinics and healthcare settings. Colorimetric dosimeters were strategically distributed at different points and vertical levels to monitor UV-C radiation distribution in the environment. The emission spectrum and radiation intensity were measured using spectral measurement techniques, while microbiological analyses were conducted on seven commonly encountered surfaces in dental offices using mannitol salt agar selective for Staphylococcus aureus and Staphylococcus epidermidis. The results revealed a significant reduction in colony-forming units (CFUs), exceeding 90% at most sampling points (p < 0.05). An exponential falloff of irradiance with distance from the UV-C source was observed, highlighting the importance of proper positioning of the equipment. Notably, the UV-C device proved effective even on surfaces with higher microbial loads, such as the armrest of the dental chair. The findings demonstrate that both time and distance significantly affect disinfection efficacy, and that purpose-built UV-C devices are viable as complementary tools to conventional chemical cleaning and disinfection protocols.","PeriodicalId":20133,"journal":{"name":"Photochemistry and Photobiology","volume":" ","pages":"1100-1111"},"PeriodicalIF":2.6,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13575693/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145998708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

RAD51 and RAD51 paralog inhibition sensitizes nonreplicating quiescent keratinocytes to UV radiation. RAD51和RAD51平行抑制使非复制的静止角质形成细胞对紫外线辐射敏感。

IF 2.6 4区生物学

Photochemistry and Photobiology Pub Date : 2026-09-01 Epub Date: 2026-02-11 DOI: 10.1111/php.70079

Saman Khan, Angitha Nair, M Alexandra Carpenter, Michael G Kemp

{"title":"RAD51 and RAD51 paralog inhibition sensitizes nonreplicating quiescent keratinocytes to UV radiation.","authors":"Saman Khan, Angitha Nair, M Alexandra Carpenter, Michael G Kemp","doi":"10.1111/php.70079","DOIUrl":"10.1111/php.70079","url":null,"abstract":"UV radiation (UVR) leads to the formation of potentially lethal and chromosome-destabilizing double-strand breaks (DSBs) in DNA. However, most studies on UVR-induced DSB formation and repair have used cells that are actively progressing throughout the cell cycle. To explore how nonreplicating, quiescent cells deal with UVR-induced DSBs, we used small-molecule inhibitors of various DSB repair pathways and unexpectedly observed a major role for the recombination protein RAD51 in promoting quiescent HaCaT keratinocyte survival. We further observed that both DSB formation and RAD51 function occur independently of nucleotide excision repair, which generates potentially unstable single-stranded DNA gaps. However, RAD51 inhibition also sensitizes quiescent cells to agents that are known to inhibit transcription, thus suggesting a role for transcription in UVR-induced DSB formation. Interestingly, siRNA-mediated knockdown of RAD51 did not sensitize cells to UVR to the same extent as pharmacological inhibition did. In contrast, knockdown of several Rad51 paralogs negatively impacted cell viability after UVR exposure, similar to pharmacological inhibition, suggesting that pharmacological inhibitors of RAD51 may also target one or more RAD51 paralogs. In summary, these findings highlight the important roles of RAD51 and its paralogs in promoting quiescent cell survival in response to UVR.","PeriodicalId":20133,"journal":{"name":"Photochemistry and Photobiology","volume":" ","pages":"1138-1149"},"PeriodicalIF":2.6,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13377540/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146166118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0