ObjectiveTo explore the mechanism by which Yizhi Qingxin prescription improves mitochondrial dysfunction in Alzheimer's disease （AD） through regulating mitochondrial Ca²⁺ homeostasis and kinetic balance based on the protein kinase A （PKA）/calcineurin （CaN） signaling pathway. MethodsSixty three-month-old amyloid precursor protein （APP）/presenilin 1 （PS1） double transgenic mice were randomly divided into a model group， a donepezil group（0.65 mg·kg^-1）， a low-dose Yizhi Qingxin prescription group （YQF-L，2.6 g·kg^-1）， a medium-dose Yizhi Qingxin prescription group （YQF-M，5.2 g·kg^-1）， and a high-dose Yizhi Qingxin prescription group （YQF-H，10.4 g·kg^-1）， with 12 mice in each group. Twelve C57BL/6J mice with the same genetic background served as a normal group. Each treatment group received gavage administration daily， with the model and normal groups receiving equal volume of physiological saline. Intervention continued for 12 consecutive weeks. The learning and memory abilities of the mice were assessed using the novel object recognition （NOR） and Morris water maze （MWM） tests. Hematoxylin-eosin （HE）/Nissl staining was used to observe histopathological changes in the hippocampus. Transmission electron microscopy （TEM） was used to observe mitochondrial ultrastructure. Fluo-4 acetoxymethyl ester （Fluo-4 AM） Ca²⁺ probe was used to measure intracellular Ca²⁺ concentration in brain tissue. Western blot was used to determine the protein expression of PKA， CaN， sodium/calcium/lithium exchanger （NCLX）， mitochondrial calcium uniporter （MCU）， calmodulin （CaM）， dynamin-related protein 1 （Drp1）， and phosphorylated dynamin-related protein 1 （serine 637 site） ［p-Drp1（S637）］ in the hippocampus. Real-time quantitative polymerase chain reaction （Real-time PCR） was used to measure the expression of PKA， CaN， CaM， NCLX， MCU， and Drp1 mRNAs. ResultsCompared with those in the normal group， the recognition index （RI） of the model group decreased （P0.01）， and the number of crossings through the original platform area， the duration of stay in the target quadrant， and the distance were reduced （P0.01）. The protein expression of PKA， NCLX， and p-DRP1 （ser637） significantly decreased （P0.05）， and the mRNA expression of PKA and NCLX significantly decreased （P0.05）. The escape latency （EL） was prolonged （P0.05）， and the intracellular Ca²⁺ level significantly increased （P0.01）. The protein expression of CaN， CaM， MCU， and Drp1， as well as the mRNA expression of CaN， MCU， and Drp1， significantly increased （P0.05）. After intervention with Donepezil and Yizhi Qingxin prescription， compared with that in the model group， the RI of the treatment group significantly increased （P0.05）， and the number of crossings through the platform and the duration of stay in the target quadrant significantly increased （P0.05）. The protein expression of PKA， NCLX， and p-Drp1 （ser637） and the mRNA expression of PKA and NCLX significantly increased （P0.05）. On the 4th and 5th days， the EL was shortened （P0.05）， and the intracellular Ca²⁺ level decreased （P0.05）. The protein expression of CaN， CaM， MCU， and Drp1 and the mRNA expression of CaN， MCU， and Drp1 significantly decreased （P0.05）. ConclusionYizhi Qingxin prescription regulates the PKA/CaN pathway， upregulates the expression of PKA， NCLX， and p-Drp1 （ser637） proteins， reduces the expression of CaN， CaM， MCU， and Drp1 proteins， and regulates Ca²⁺ homeostasis and mitochondrial dynamic balance， thereby enhancing the spatial learning and memory abilities of AD mice.

ObjectiveTo explore the mechanism by which Yizhi Qingxin prescription improves mitochondrial dysfunction in Alzheimer's disease （AD） through regulating mitochondrial Ca²⁺ homeostasis and kinetic balance based on the protein kinase A （PKA）/calcineurin （CaN） signaling pathway. MethodsSixty three-month-old amyloid precursor protein （APP）/presenilin 1 （PS1） double transgenic mice were randomly divided into a model group， a donepezil group（0.65 mg·kg^-1）， a low-dose Yizhi Qingxin prescription group （YQF-L，2.6 g·kg^-1）， a medium-dose Yizhi Qingxin prescription group （YQF-M，5.2 g·kg^-1）， and a high-dose Yizhi Qingxin prescription group （YQF-H，10.4 g·kg^-1）， with 12 mice in each group. Twelve C57BL/6J mice with the same genetic background served as a normal group. Each treatment group received gavage administration daily， with the model and normal groups receiving equal volume of physiological saline. Intervention continued for 12 consecutive weeks. The learning and memory abilities of the mice were assessed using the novel object recognition （NOR） and Morris water maze （MWM） tests. Hematoxylin-eosin （HE）/Nissl staining was used to observe histopathological changes in the hippocampus. Transmission electron microscopy （TEM） was used to observe mitochondrial ultrastructure. Fluo-4 acetoxymethyl ester （Fluo-4 AM） Ca²⁺ probe was used to measure intracellular Ca²⁺ concentration in brain tissue. Western blot was used to determine the protein expression of PKA， CaN， sodium/calcium/lithium exchanger （NCLX）， mitochondrial calcium uniporter （MCU）， calmodulin （CaM）， dynamin-related protein 1 （Drp1）， and phosphorylated dynamin-related protein 1 （serine 637 site） ［p-Drp1（S637）］ in the hippocampus. Real-time quantitative polymerase chain reaction （Real-time PCR） was used to measure the expression of PKA， CaN， CaM， NCLX， MCU， and Drp1 mRNAs. ResultsCompared with those in the normal group， the recognition index （RI） of the model group decreased （P0.01）， and the number of crossings through the original platform area， the duration of stay in the target quadrant， and the distance were reduced （P0.01）. The protein expression of PKA， NCLX， and p-DRP1 （ser637） significantly decreased （P0.05）， and the mRNA expression of PKA and NCLX significantly decreased （P0.05）. The escape latency （EL） was prolonged （P0.05）， and the intracellular Ca²⁺ level significantly increased （P0.01）. The protein expression of CaN， CaM， MCU， and Drp1， as well as the mRNA expression of CaN， MCU， and Drp1， significantly increased （P0.05）. After intervention with Donepezil and Yizhi Qingxin prescription， compared with that in the model group， the RI of the treatment group significantly increased （P0.05）， and the number of crossings through the platform and the duration of stay in the target quadrant significantly increased （P0.05）. The protein expression of PKA， NCLX， and p-Drp1 （ser637） and the mRNA expression of PKA and NCLX significantly increased （P0.05）. On the 4th and 5th days， the EL was shortened （P0.05）， and the intracellular Ca²⁺ level decreased （P0.05）. The protein expression of CaN， CaM， MCU， and Drp1 and the mRNA expression of CaN， MCU， and Drp1 significantly decreased （P0.05）. ConclusionYizhi Qingxin prescription regulates the PKA/CaN pathway， upregulates the expression of PKA， NCLX， and p-Drp1 （ser637） proteins， reduces the expression of CaN， CaM， MCU， and Drp1 proteins， and regulates Ca²⁺ homeostasis and mitochondrial dynamic balance， thereby enhancing the spatial learning and memory abilities of AD mice.

: To analyze the prevalence of anemia and iron deficiency among primary and secondary school students in Rural Nutrition Improvement Program areas of Guizhou Province in 2023, and to explore the related factors, so as to provide evidence for Rural Nutrition Improvement Program optimization. Methods: In September 2023, a stratified random cluster sampling strategy was used to select 40 rural compulsory education schools with rural nutrition improvement program in five counties of Guizhou Province. School level questionnaire was employed to collect information of basic characteristics and school meal implementation. A total of 7 826 primary and secondary school students aged 6-16 underwent anthropometry and hemoglobin (Hb) determination; serum ferritin (SF) was additionally measured in a random subsample of 1 795 pupils. Students in Grade 3 and above also completed a questionnaire covering demographic characteristics, dietary behaviours and nutrition knowledge. Group comparisons were conducted by Chi square test or Fisher s exact test, and multivariable Logistic regression models were constructed to identify factors associated with anemia and iron deficiency. Results: The overall Hb level was (133.21±12.95)g/L, with an anemia prevalence of 7.17%. The overall SF level was (69.58±59.01)μg/L, with an iron deficiency prevalence of 2.73%. Multivariable analysis showed that stunting ( OR =1.88), school menus without nutrient calculation ( OR =1.61) and absence of menu planning software in the current semester ( OR =2.34) independently increased anemia risk, whereas obesity reduced it ( OR =0.54) (all P <0.05). Girls ( OR =4.16) and Grades 7-9 ( OR =5.93) increased iron deficiency risk (both P <0.05). Compared with rarely eating fresh vegetables, students with consuming <3 kinds per day ( OR =0.08) or exactly 3 kinds per day ( OR =0.06) had lower iron deficiency risks (both P <0.05). Conclusions Anemia and iron deficiency are prevalent among primary and secondary school students in Guizhou. Targeted intervention measures should be implemented for key populations to enhance the effectiveness of nutrition improvement program.

Objective: To develop a 24 hour physical activity index for school aged children, and to analyze the association of 24 hour physical activity index with screening myopia and obesity, so as to provide a more effective assessment tool for student health risk screening. Methods: From April to June 2024, a total of 451 students in Grades 3-4 from two monitored primary schools in Shanghai were selected using stratified cluster random sampling method. Data on eight core indicators, including daily moderate to vigorous physical activity time, total physical activity time, outdoor activity time, screen time, sleep duration, sleep efficiency, social jetlag and daytime sleepiness, were collected through questionnaires and accelerometer monitoring. Each indicator was standardized and synthesized into a 0-80 point school aged children s 24 hour physical activity index. Spearman correlation analysis and t-test were used to assess consistency between questionnaire and accelerometer derived indices. Multivariate Logistic regression was applied to analyze the association of strength of the composite index with single behavior indicators in screening myopia and overweight/obesity. Results: The compliance rates were higher for moderate to vigorous physical activity time and screen time (50.8%, 98.7%), while the compliance rate for outdoor activity time was only 42.6%, and that for sufficient sleep duration was merely 10.2%. There was no significant difference between the total scores derived from the questionnaire and accelerometer methods (45.13±5.83, 45.05±6.87, t=0.29, P >0.05), but they showed a strong positive correlation ( r=0.58, P <0.01). Multivariate Logistic regression revealed that adjusting for individual behaviors such as grade, gender and both parents being myopic, among single behavior indicators of 24 hour physical activity index, only insufficient outdoor activity time was significantly associated with screening myopia among school aged children ( OR=1.50, 95%CI =1.01-2.21); the detection risk of screening myopia and obesity in the low index group were higher than those in the high index group ( OR=2.47, 95%CI =1.02-5.96; OR=16.63,95%CI = 5.99- 46.20) (all P <0.05). Conclusion The developed 24 hour physical activity index for school aged children demonstrates good measurement accuracy and shows stronger associations with screening myopia and obesity than single behavior indicator.

Objective:To evaluate the clinical outcomes of combined complete preservation of chordal structure mitral valve replacement (C-MVR) with total anatomical arterial myocardial revascularization (TACR) in coronary patients with moderate-to-severe or severe ischemic mitral regurgitation (IMR).Methods:This is a retrospective multi-center case series study. Data were retrospectively collected from 127 patients with coronary artery disease with moderate to severe or severe IMR who received TACR with C-MVR from July 2015 to April 2024 in 13 hospitals in China. There were 90 males and 37 females, aged (56.5±10.7) years (range: 33 to 74 years). Perioperative data and follow-up data including left ventricular ejection fraction, left ventricular end-diastolic diameter, and patency rate of arterial grafts of patients were collected. Comparisons were made using paired sample t-test or χ2 test. Results:In this cohort of 127 patients, 67 underwent concurrent tricuspid valve repair. During surgery, 113 grafts of the left internal mammary artery (LIMA), 127 grafts of the left radial artery, 80 grafts of the right radial artery, and 110 grafts of the right internal mammary artery (RIMA) were harvested. The number of the distal anastomosis was 4.2±0.4 (range: 3 to 5). The aortic cross-clamp time and cardiopulmonary bypass time were (97.5±23.4) minutes (range: 90 to 161 minutes) and (145.4±19.2) minutes (range: 101 to 210 minutes), respectively. There was one operative death. Intraoperative placement of an intra-aortic balloon pump was performed in 21 patients to improve the left ventricular ejection. No sternal ischemic occurred. All patients completed follow-up, with a mean follow-up period of (64.3±7.5) months (range: 4 to 110 months). No major cerebrovascular events occurred during the follow-up period, and all patients survived. Left ventricular ejection fraction improved postoperatively (55.0%±5.3% vs. 41.0%±15.3%, t=17.23, P<0.01). The proportion of patients with New York Heart Association functional class ≤2 increased postoperatively (23.6% (30/127) vs. 87.3% (110/126), χ2=103.77, P<0.01). The proportion of patients with Canadian Cardiovascular Society Angina Classification ≤3 decreased postoperatively (4.8% (6/126) vs. 78.7% (100/127), χ2=142.19, P<0.01). The left ventricular end-diastolic diameter decreased postoperatively ((5.70±4.50) cm vs. (6.10±0.23) cm, t=12.15, P<0.01). Coronary multi-detector computed tomography angiography (MDCTA) follow-up was conducted for (60.5±11.7) months (range: 6 to 109 months) postoperatively. MDCTA confirmed the patency rates of the grafts: 96.4% (108/112) for the LIMA grafts, 88.9% (112/126) for the left radial artery grafts, 93.7% (74/79) for the right radial artery grafts, and 90.9% (100/110) for the free RIMA grafts. No significant differences in graft patency rates were observed between the arterial grafts ( χ2=5.24, P=0.155). Conclusion:The results of this multi-centre study demonstrate satisfactory mid-term results of C-MVR with TACR for the treatment of coronary artery disease with moderate to severe or severe IMR.

The Expert Consensus on Clinical Application of Qinbaohong Zhike Oral Liquid in Treatment of Acute Bronchitis and Acute Attack of Chronic Bronchitis （GS/CACM 337-2023） was released by the China Association of Chinese Medicine on December 13^th， 2023. This expert consensus was developed by experts in methodology， pharmacy， and Chinese medicine in strict accordance with the development requirements of the China Association of Chinese Medicine （CACM） and based on the latest medical evidence and the clinical medication experience of well-known experts in the fields of respiratory medicine （pulmonary diseases） and pediatrics. This expert consensus defines the application of Qinbaohong Zhike oral liquid in the treatment of cough and excessive sputum caused by phlegm-heat obstructing lung， acute bronchitis， and acute attack of chronic bronchitis from the aspects of applicable populations， efficacy evaluation， usage， dosage， drug combination， and safety. It is expected to guide the rational drug use in medical and health institutions， give full play to the unique value of Qinbaohong Zhike oral liquid， and vigorously promote the inheritance and innovation of Chinese patent medicines.

Objective:To evaluate the clinical outcomes of combined complete preservation of chordal structure mitral valve replacement (C-MVR) with total anatomical arterial myocardial revascularization (TACR) in coronary patients with moderate-to-severe or severe ischemic mitral regurgitation (IMR).Methods:This is a retrospective multi-center case series study. Data were retrospectively collected from 127 patients with coronary artery disease with moderate to severe or severe IMR who received TACR with C-MVR from July 2015 to April 2024 in 13 hospitals in China. There were 90 males and 37 females, aged (56.5±10.7) years (range: 33 to 74 years). Perioperative data and follow-up data including left ventricular ejection fraction, left ventricular end-diastolic diameter, and patency rate of arterial grafts of patients were collected. Comparisons were made using paired sample t-test or χ2 test. Results:In this cohort of 127 patients, 67 underwent concurrent tricuspid valve repair. During surgery, 113 grafts of the left internal mammary artery (LIMA), 127 grafts of the left radial artery, 80 grafts of the right radial artery, and 110 grafts of the right internal mammary artery (RIMA) were harvested. The number of the distal anastomosis was 4.2±0.4 (range: 3 to 5). The aortic cross-clamp time and cardiopulmonary bypass time were (97.5±23.4) minutes (range: 90 to 161 minutes) and (145.4±19.2) minutes (range: 101 to 210 minutes), respectively. There was one operative death. Intraoperative placement of an intra-aortic balloon pump was performed in 21 patients to improve the left ventricular ejection. No sternal ischemic occurred. All patients completed follow-up, with a mean follow-up period of (64.3±7.5) months (range: 4 to 110 months). No major cerebrovascular events occurred during the follow-up period, and all patients survived. Left ventricular ejection fraction improved postoperatively (55.0%±5.3% vs. 41.0%±15.3%, t=17.23, P<0.01). The proportion of patients with New York Heart Association functional class ≤2 increased postoperatively (23.6% (30/127) vs. 87.3% (110/126), χ2=103.77, P<0.01). The proportion of patients with Canadian Cardiovascular Society Angina Classification ≤3 decreased postoperatively (4.8% (6/126) vs. 78.7% (100/127), χ2=142.19, P<0.01). The left ventricular end-diastolic diameter decreased postoperatively ((5.70±4.50) cm vs. (6.10±0.23) cm, t=12.15, P<0.01). Coronary multi-detector computed tomography angiography (MDCTA) follow-up was conducted for (60.5±11.7) months (range: 6 to 109 months) postoperatively. MDCTA confirmed the patency rates of the grafts: 96.4% (108/112) for the LIMA grafts, 88.9% (112/126) for the left radial artery grafts, 93.7% (74/79) for the right radial artery grafts, and 90.9% (100/110) for the free RIMA grafts. No significant differences in graft patency rates were observed between the arterial grafts ( χ2=5.24, P=0.155). Conclusion:The results of this multi-centre study demonstrate satisfactory mid-term results of C-MVR with TACR for the treatment of coronary artery disease with moderate to severe or severe IMR.

OBJECTIVE To analyze the occurrence characteristics and risk factors of adverse drug reactions （ADR） of gemcitabine for injection in national centralized volume-based procurement （hereinafter referred to as “centralized procurement”）， and provide reference for clinical safe drug use. METHODS A retrospective study was conducted to collect the relevant case reports of gemcitabine for injection reported to the National Adverse Drug Reaction Monitoring System by Inner Mongolia Autonomous Region from January 2022 to December 2023； basic information of patients， drug use status， patient outcomes， rational drug use and other information were collected， and the occurrence characteristics of ADRs with leukopenia， myelosuppression， neutropenia， thrombocytopenia and liver dysfunction were analyzed. Univariate analysis and multivariate Logistic regression were used to analyze the correlation of gender， age， combination of antitumor drugs， original malignant tumor and drug dose with ADR. RESULTS A total of 315 cases reports （315 patients） of gemcitabine-induced ADR were included in this study， with a male-to-female ratio of 1.42∶1 and age of （61.17±9.13） years. The primary malignant tumor was pancreatic cancer （73 cases， 23.17%）. Leukopenia， myelosuppression and nausea were the most common ADR， followed by neutropenia， thrombocytopenia， liver dysfunction and so on. The severity grade of ADR was mainly 1-2， and the outcome of most ADR was good. Multivariate Logistic regression analysis showed that combination of antitumor drugs was a risk factor for myelosuppression and neutropenia （RR＝2.154， 95%CI： 1.218- 3.807， P＝0.008； RR＝3.099， 95%CI： 1.240-7.744， P＝0.016）； gender （female） was a risk factor for leukopenia and liver dysfunction （RR＝0.508， 95%CI： 0.302-0.853， P＝0.010； RR＝0.301， 95%CI： 0.102-0.887， P＝0.029）. In terms of drug use rationality， there were 143 cases （45.40%） of drug 126.com use in accordance with the indications of the label， and 172 cases （54.60%） of off-label drug use. Among them， the primary malignant tumors were bladder cancer， bile duct cancer and ovarian cancer， which ranked the top three off-label drug use. CONCLUSIONS The ADR caused by gemcitabine in Inner Mongolia is mainly in the blood and digestive systems. The severity of ADRs is mainly classified as 1-2 levels， and most ADRs have good outcomes. Gender （female） and combination medication are risk factors for gemcitabine-induced ADR. Appropriate chemotherapy regimen should be selected according to the patient’s condition and physical condition， and ADR monitoring in blood and digestive systems should be strengthened during medication of gemcitabine.

ObjectiveTo investigate the potential mechanism of action of the Qufeng Tongqiao Cough-relieving Decoction （祛风通窍止咳方， QTCD） in the treatment of upper airway cough syndrome （UACS）. MethodsTwenty-four guinea pigs were randomly divided into blank group， model group， traditional Chinese medicine （TCM） group， and inhibitor group， with six guinea pigs in each group. Except for the blank group， guinea pigs were sensitized with ovalbumin and aluminum hydroxide via intraperitoneal injection， followed by ovalbumin nasal drops combined with smoke exposure to establish the UACS model. After modeling， the TCM group was administered QTCD 0.9 g/（100 g·d） by gavage， the inhibitor group received the transient receptor potential vanilloid receptor 4 （TRPV4） inhibitor GSK2193874 1 mmol/L， 5 min by nebulisation， and the blank group and model group were given 2 ml/（100 g·d） normal saline by gavage once daily. After 7 days of treatment， a cough provocation test was performed using 0.4 mol/L citric acid. The levels of IgE in serum and inflammatory cytokines， including interleukin-6 （IL-6）， interleukin-8 （IL-8） in serum， bronchoalveolar lavage fluid （BALF）， and nasal lavage fluid （NLF） were detected by enzyme-linked immunosorbent assay （ELISA）. Histopathological changes in lung and nasal mucosal tissues were observed by hematoxylin-eosin （HE） staining. Immunohistochemistry was used to detect the protein levels of TRPV4， substance P （SP）， and calcitonin gene-related peptide （CGRP） in lung and nasal mucosal tissues. Real-time polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of TRPV4， SP， and CGRP in lung tissues. ResultsHE staining showed significant structural damage and infiltration of inflammatory cells in the lung and nasal mucosal tissues in the model group， while the TCM group and inhibitor group showed improved pathological changes. Compared with the blank group， the model group showed increased cough frequency， serum IgE level， and IL-6 and IL-8 levels in serum， BALF， and NLF. The protein levels of TRPV4， SP， and CGRP in lung and nasal mucosal tissues and their mRNA expression were elevated （P＜0.05 or P＜0.01）. Compared with the model group， the TCM group and inhibitor group showed reduced cough frequency， serum IgE level， and TRPV4 and SP mRNA expression in lung tissues. The TCM group showed reduced IL-6 and IL-8 levels in serum， BALF， and NLF， and reduced TRPV4 and CGRP protein levels in lung and nasal mucosal tissues. The inhibitor group showed reduced IL-6 and IL-8 levels in serum， BALF， and NLF， reduced IL-6 in BALF， reduced IL-8 in NLF， and decreased TRPV4， SP， and CGRP protein levels in lung tissues and SP and CGRP protein levels in nasal mucosal tissues （P＜0.05 or P＜0.01）. Compared with the TCM group， the inhibitor group had increased serum IgE， IL-6， and IL-8 levels， increased IL-6 level in BALF， and increased IL-8 levle in NLF， but decreased SP protein level in lung tissues and increased TRPV4 and SP mRNA expression in lung tissues （P＜0.01）. ConclusionQTCD effectively reduces cough frequency in the UACS guinea pig model. Its mechanism may involve inhibiting the activation of the TRPV4 pathway， improving airway neurogenic inflammation， alleviating inflammatory responses， and reducing cough hypersensitivity.

Background: Nasopharyngeal carcinoma (NPC) is characterized by high programmed death-ligand 1 (PD-L1) expression and abundant infiltration of non-malignant lymphocytes, which renders patients potentially suitable candidates for immune checkpoint blockade therapies. Palate, lung, and nasal epithelium clone (PLUNC) inhibit the growth of NPC cells and enhance cellular apoptosis and differentiation. Currently, the relationship between PLUNC (as a tumor-suppressor) and PD-L1 in NPC is unclear. Methods: We collected clinical samples of NPC to verify the relationship between PLUNC and PD-L1. PLUNC plasmid was transfected into NPC cells, and the variation of PD-L1 was verified by western blot and immunofluorescence. In NPC cells, we verified the relationship of PD-L1, activating transcription factor 3 (ATF3), and β-catenin by western blot and immunofluorescence. Later, we further verified that PLUNC regulates PD-L1 through β-catenin. Finally, the effect of PLUNC on β-catenin was verified by co-immunoprecipitation (Co-IP). Results: We found that PLUNC expression was lower in NPC tissues than in paracancer tissues. PD-L1 expression was opposite to that of PLUNC. Western blot and immunofluorescence showed that β-catenin could upregulate ATF3 and PD-L1, while PLUNC could downregulate ATF3/PD-L1 by inhibiting the expression of β-catenin. PLUNC inhibits the entry of β-catenin into the nucleus. Co-IP experiments demonstrated that PLUNC inhibited the interaction of DEAD-box helicase 17 (DDX17) and β-catenin. Conclusions PLUNC downregulates the expression of PD-L1 by inhibiting the interaction of DDX17/β-catenin in NPC.