Metastatic patterns of level II-V cervical lymph nodes assessed per vertebral levels in nasopharyngeal carcinoma.

BACKGROUND AND PURPOSE: The current cervical lymph nodes classification system is not perfectly reasonable for radiotherapy of nasopharyngeal carcinoma (NPC). This study aimed to determine the metastatic patterns of level II-V lymph nodes in NPC by using vertebrae as anatomical landmarks. MATERIALS AND METHODS: Four hundred and forty node-positive NPC patients were selected. Metastatic lymph nodes were diagnosed using positron emission tomography/computed tomography scan or magnetic resonance imaging. We evaluated univariate and multivariate logistic correlations between the vertebral levels of metastatic level II-V lymph nodes. RESULTS: The metastasis rate of level II-V lymph nodes gradually decreased from C2 (66.5%) and C3 (68.2%) to T1 (4.1%) vertebral levels. When assessed per vertebral level, 98.4% were non-skip metastasis. The interval of vertebral levels and distance between the inferior border of the tumor and the metastatic lymph nodes were similar in N1 and N2 patients. Univariate correlation analysis showed the metastasis of level II-V lymph nodes at each vertebral level was associated with the metastasis at any other vertebral level. In the multivariate analysis, metastasis at any one of the C2-C7 vertebral levels strongly and positively correlated with metastasis at two adjacent vertebral levels, including one level above and one below. CONCLUSION: This is the first study to report the distribution and non-skip metastatic patterns of level II-V lymph nodes assessed per vertebral levels in NPC. The low-risk clinical target volume could be reduced to two vertebral levels below the vertebral level of the metastatic level II-V nodes when both imaging modalities are available.

Disparities in positive results and dissemination of randomized controlled trials in immuno-oncology.

BACKGROUND: This cross-sectional and longitudinal analysis aimed to demonstrate the disparities in positive results and dissemination patterns of randomized controlled trials (RCTs) in global immuno-oncology (IO). METHODS: Phase II-IV RCTs with results reported by article publications registered on ClinicalTrials.gov in 2007-2018 studying immune checkpoint inhibitors (ICIs), adoptive cell transfer, cancer vaccines, and immune modulators were included. RESULTS: Twenty-eight percent of trials were positive (72 of 258), most of which were pharma-sponsored and focused on ICI and multiple IO therapies in lung cancer, melanoma, and multiple cancer types. The recent period of trial start year, upfront registration, large sample size, high strictness score on corticosteroid/infection-related criteria, and survival endpoints were associated with positive results. Trials from Mainland China had a faster publication timeline of positive results but lacked study diversity or full reporting of negative results compared with US and multinational trials. Compared with phase II trials, phase III-IV trials had a higher average proportion of positive results (28.9% vs. 22.2%) and a more stable change over the past decade (23.65% vs. 49.24%). Positive trials yielded more secondary manuscripts (10 vs. 4), a shorter publication process of approximately two years (P < 0.001), and a superiority in the dissemination of journals with an h-index >90 (P < 0.001) compared with negative trials. CONCLUSION: Disparities in positive result dissemination are widespread in IO RCTs and affected by trial features. We proposed improvements in upfront registration, procedural integrity, and adequate inclusion of rival trials reporting negative results within the earlier two years in future reviews.

Immuno-oncology (IO) is a novel treatment modality utilizing the natural ability of body's immune system to fight against cancer. The acknowledged standard method to confer the best medical evidence for showing the efficacy of a new intervention is randomized controlled trials (RCTs), and the publication of trial results via journal articles usually modifies medical decisions. A trial labeled negative means that the pre-specified goal was not met, but it deserves more attention rather than a simple interpretation of scientific failure. Previous studies on oncology trials indicated that negative and positive trials have different patterns of result publication and varied trial features. Although IO-related RCTs obtain a continuously increasing number, the extent and tendencies (positive or negative) of their results have not been assessed. To conduct a timely summary and a comprehensive analysis focusing on the publication details and its relationship with the properties of IO trials, we included phase II­IV IO RCTs with results reported by article publications registered on ClinicalTrials.gov in 2007­2018. We found that disparities in positive results and publication are widespread in IO RCTs and severely affected by IO category, cancer type, sponsorship, trial phase, and geographic origin. Positive trials had a significantly shorter publication timeline of approximately two years, more secondary manuscripts, and a superiority in high-quality publications over negative trials. We propose that investigators should complete registration before trial launch, improve procedural integrity, and allow an adequate inclusion of rival trials reporting negative results within the earlier two years in future IO-related reviews.

A pyroptosis expression pattern score predicts prognosis and immune microenvironment of lung squamous cell carcinoma.

Pyroptosis has been proved to significantly influence the development of lung squamous cell carcinoma (LUSC). To better predict overall survival (OS) and provide guidance on the selection of therapy for LUSC patients, we constructed a novel prognostic biomarker based on pyroptosis-related genes. The dataset for model construction were obtained from The Cancer Genome Atlas and the validation dataset were obtained from Gene Expression Omnibus. Differential expression genes between different pyroptosis expression patterns were identified. These genes were then used to construct pyroptosis expression pattern score (PEPScore) through weighted gene co-expression network analysis, univariate and multivariate cox regression analysis. Afterward, the differences in molecule and immune characteristics and the effect of different therapies were explored between the subgroups divided by the model. The PEPScore was constructed based on six pyroptosis-related genes (CSF2, FGA, AKAP12, CYP2C18, IRS4, TSLP). Compared with the high-PEPScore subgroup, the low-PEPScore subgroup had significantly better OS, higher TP53 and TTN mutation rate, higher infiltration of T follicular helper cells and CD8 T cells, and may benefit more from chemotherapeutic drugs, immunotherapy and radiotherapy. PEPScore is a prospective prognostic model to differentiate prognosis, molecular and immune microenvironmental features, as well as provide significant guidance for selecting clinical therapies.

Development and validation of a joint model for dynamic prediction of overall survival in nasopharyngeal carcinoma based on longitudinal post-treatment plasma cell-free Epstein-Barr virus DNA load.

OBJECTIVES: To develop and validate a joint model for dynamic prediction of overall survival (OS) in nasopharyngeal carcinoma (NPC) based on longitudinal post-treatment plasma cell-free Epstein-Barr virus (cfEBV) DNA load. PATIENTS AND METHODS: We analyzed 695 patients with non-metastatic NPC and detectable post-treatment cfEBV DNA load who did not receive adjuvant therapy. We fitted the trajectories of post-treatment cfEBV DNA load as a function of time into a linear mixed-effect model and fitted a Cox regression model with covariates including age, T and N stages, and lactate dehydrogenase level. Finally, we combined both via joint modeling to develop and validate our dynamic model. RESULTS: A strong positive correlation was found between the individual longitudinal post-treatment cfEBV DNA load and the risk of death from any cause (P < 0.001). We developed a joint model capable of providing subject-specific dynamic prediction of conditional OS based on the evolution of the individual plasma cfEBV DNA load trajectory. The joint model showed reliable performance in both training and validation cohorts, with a large area under the curve (interquartile range [IQR]: training cohort, 0.775-0.850; validation cohort, 0.826-0.900) and low prediction errors (IQR: training cohort, 0.017-0.078; validation cohort, 0.034 -0.071). An increasing amount of data on cfEBV DNA load was associated with better model performance. CONCLUSION: Our model provided reliable subject-specific dynamic prediction of conditional OS, which could help guide individualized post-treatment surveillance, risk stratification, and management of NPC in the future.

Contribution of insurance status to the association between marital status and cancer-specific survival: a mediation analysis.

OBJECTIVES: To evaluate the extent to which marriage influences cancer-specific survival (CSS) by influencing the insurance status among patients with common solid cancers and the feasibility of reducing the survival gap caused by marriage by increasing private insurance coverage for unmarried patients. SETTING: A retrospective cohort study with patients retrieved from the Surveillance, Epidemiology and End Results programme. PARTICIPANTS: Patients with nine common solid cancers diagnosed between 2007 and 2016 were included. Patients were excluded if their marital status, insurance status, socioeconomical status, stage or cause of death was unavailable, if survival time was less than 1 month, or if they were younger than 18 years at the time of diagnosis. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was CSS, which was compared between married and unmarried individuals. Mediation analyses were conducted to determine the contribution of insurance status to the association between marriage and CSS. RESULTS: Married patients had better CSS than those unmarried (time ratio 1.778; 95% CI 1.758 to 1.797). Private health insurance was a key factor mediating the association between marital status and CSS (proportion mediated (PM), 17%; 95% CI 17% to 17.1%). The PM ranges from 10.7% in prostate cancer to 20% in kidney cancer. The contribution of private insurance to the association between marital status and CSS was greater among women than among men (PM 18.5% vs 16.7%). The mediating effect of private insurance was the greatest for the comparison between married and separated individuals (PM 25.6%; 95% CI 25.3% to 25.8%) and smallest for the comparison between married and widowed individuals (PM 11.0%; 95% CI 10.9% to 11.1%). CONCLUSIONS: 17% of the marital disparities in CSS are mediated by private insurance coverage. Increasing private insurance coverage for unmarried patients may reduce the survival gap related to marital status and sex. However, it is unclear whether better publicly funded insurance would have the same effect.

Selection and validation of chemotherapy beneficiaries among elderly nasopharyngeal carcinoma (NPC) patients treated with intensity-modulated radiation therapy (IMRT): a large real-world study.

PURPOSE: Using real-world evidence, this study aimed to identify elderly nasopharyngeal carcinoma (NPC) patients who would benefit from chemotherapy. METHODS AND MATERIALS: 1714 elderly NPC patients between April 2007 and December 2017 were identified. Recursive partitioning analysis (RPA) was used to generate risk-stratified outcomes. Prognostic factors were performed for individual comparisons of different risk groups to assess chemotherapy benefits. RESULTS: The median follow-up was 59.3 (0.39-170.09) months. Epstein Barr virus (EBV) DNA and T stage were included in the RPA-generated risk stratification, categorizing patients into a good-prognosis group (EBV DNA ≤ 4000 copies/mL & T1-2), and a poor-prognosis group (EBV DNA ≤ 4000 copies/mL & T3-4 and EBV DNA > 4000 copies/mL & any T). Overall survival (OS) was significantly higher in the good-prognosis group compared with the training set (HR = 0.309, 95% CI 0.184-0.517; P < 0.001), and validated in the testing set (HR = 0.276, 95% CI 0.113-0.670; P = 0.002). In the poor-prognosis group, a significantly improved OS for chemoradiotherapy (CRT) compared with RT alone was observed (HR = 0.70, 95% CI 0.55-0.88; P = 0.003). Patients who received induction chemotherapy (IC) + concurrent chemoradiotherapy (CCRT) and CCRT had a significantly improved OS compared with RT alone (IC + CCRT vs. RT alone: P = 0.002; CCRT vs. RT alone: P = 0.008) but not in the IC + RT group (P = 0.306). The 5-year OS for CRT versus RT-alone with ACE-27 scores of 0, 1 and 2 were 76.0% versus 70.0% (P = 0.014), 80.5% versus 68.2% (P = 0.150) and 58.5% versus 62.2% (P = 0.490), respectively; for those aged 60-64, 65-70 and ≥ 70 years old they were 80.9% versus 75.9% (P = 0.068), 73.3% versus 63.4% (P = 0.270) and 64.8% versus 67.1% (P = 0.820), respectively. CONCLUSIONS: For elderly NPC patients a simple screening cutoff for chemotherapy beneficiaries might be EBV DNA < 4000 copies/ml & T3-4 and EBV DNA ≥ 4000 copies/ml & any T, but not for those > 70 years old and with an ACE-27 score > 1. IC + CCRT and CCRT were effective forms of chemotherapy.

Development of a prediction model for radiotherapy response among patients with head and neck squamous cell carcinoma based on the tumor immune microenvironment and hypoxia signature.

INTRODUCTION: The immune system and hypoxia are major factors influencing radiosensitivity in patients with different cancer types. This study aimed at developing a model to predict radiotherapy response in patients with head and neck squamous cell carcinoma (HNSCC) based on the tumor immune microenvironment and hypoxia signature. MATERIALS AND METHODS: We first evaluated the hypoxia status and tumor immune microenvironment in the Cancer Genome Atlas (TCGA) cohort by using transcriptomic data. Differentially expressed genes (DEGs) were identified between the "high immunity and low hypoxia" and "low immunity and high hypoxia" groups and those DEGs significantly associated with disease-specific survival in the univariate Cox regression analysis were selected as the prognostic DEGs. We selected the immune hypoxia-related genes (IHRGs) by intersecting prognostic DEGs with immune and hypoxia gene sets. We used the IHRGs to train a multivariate Cox regression model in the TCGA cohort, based on which we calculated the IHRG prognostic index (IHRGPI) for each patient and validated its efficacy in predicting radiotherapy response in the Gene Expression Omnibus cohorts. Furthermore, we explored potential mechanisms and effective combinational treatment strategies for different IHRGPI groups. RESULTS: Five IHRGs were used to construct the IHRGPI, which was used to dichotomize the cohorts. The patients with lower IHRGPI showed a better radiotherapy response across different cohorts and endpoints, including overall survival, progression-free survival, and recurrence-free survival (p < 0.05). Patients with higher IHRGPI showed greater hypoxia and lesser immune cell infiltration. A lower IHRGPI indicated a better immunotherapy response, while a higher IHRGPI indicated a better chemotherapy response. CONCLUSIONS: IHRGPI is promising for predicting radiotherapy response and guiding combinational treatment strategies in patients with HNSCC.

Causal relationship between genetically predicted depression and cancer risk: a two-sample bi-directional mendelian randomization.

BACKGROUND: Depression has been reported to be associated with some types of cancer in observational studies. However, the direction and magnitude of the causal relationships between depression and different types of cancer remain unclear. METHODS: We performed the two-sample bi-directional mendelian randomization with the publicly available GWAS summary statistics to investigate the causal relationship between the genetically predicted depression and the risk of multiple types of cancers, including ovarian cancer, breast cancer, lung cancer, glioma, pancreatic cancer, lymphoma, colorectal cancer, thyroid cancer, bladder cancer, and kidney cancer. The total sample size varies from 504,034 to 729,150. Causal estimate was calculated by inverse variance weighted method. We also performed additional sensitivity tests to evaluate the validity of the causal relationship. RESULTS: After correction for heterogeneity and horizontal pleiotropy, we only detected suggestive evidence for the causality of genetically predicted depression on breast cancer (OR = 1.09, 95% CI: 1.03-1.15, P = 0.0022). The causal effect of depression on breast cancer was consistent in direction and magnitude in the sensitivity analysis. No evidence of causal effects of depression on other types of cancer and reverse causality was detected. CONCLUSIONS: The result of this study suggests a causative effect of genetically predicted depression on specific type of cancer. Our findings emphasize the importance of depression in the prevention and treatment of breast cancer.

Long-Term Evaluation and Normal Tissue Complication Probability (NTCP) Models for Predicting Radiation-Induced Optic Neuropathy after Intensity-Modulated Radiation Therapy (IMRT) for Nasopharyngeal Carcinoma: A Large Retrospective Study in China.

PURPOSE: To quantify the long-term evaluation of optic chiasma (OC) and/or optic nerve(s) (ONs) and to develop predictive models for radiation-induced optic neuropathy (RION) in nasopharyngeal carcinoma after intensity-modulated radiotherapy (IMRT). METHODS AND MATERIALS: A total of 3,662 patients' OC/ONs with full visual acuity and dosimetry data between 2010 and 2015 were identified. Critical dosimetry predictors of RION were chosen by machine learning and penalized regression for survival. A nomogram containing dosimetry and clinical variables was generated for predicting RION-free survival. RESULTS: The median follow-up was 71.79 (2.63-120.9) months. Sixty-six eyes in 51 patients (1.39%) developed RION. Two patients were visual field deficient, and 49 patients had visual acuity of less than 0.1 (20/200). The median latency time was 36 (3-90) months. The 3-, 5-, and 8-year cumulative incidence of RION was 0.78%, 1.19%, and 1.97%, respectively. Dmax was the most critical dosimetry variable for RION (AUC: 0.9434, the optimal cutoff: 64.48 Gy). Patients with a Dmax ≥64.48 Gy had a significantly higher risk of RION (HR = 102.25; 95%CI, 24.86-420.59; P < 0.001). Age (>44 years) (HR = 2.234, 95% CI = 1.233-4.051, p = 0.008), advanced T stage (T3 vs. T1-2: HR = 7.516, 95% CI = 1.725-32.767, p=0.007; T4 vs. T1-2: HR = 37.189, 95% CI = 8.796-157.266, P < 0.001), and tumor infiltration/compression of the OC/ONs (HR = 4.572, 95% CI = 1.316-15.874, p=0.017) were significant clinical risk factors of RION. A nomogram comprising age, T stage, tumor infiltration/compression of the OC/ON, and Dmax significantly outperformed the model, with only Dmax predicting RION (C-index: 0.916 vs. 0.880, P < 0.001 in the training set; 0.899 vs. 0.874, P=0.038 in the test set). The nomogram-defined high-risk group had a worse 8-year RION-free survival. CONCLUSIONS: In the IMRT era, Dmax <60 Gy is safe and represents an acceptable dose constraint for most NPC patients receiving IMRT. A reasonable trade-off for selected patients with unsatisfactory tumor coverage due to proximity to the optic apparatus would be Dmax <65 Gy. Caution should be exercised when treating elderly and advanced T-stage patients or those with tumor infiltration/compression of the OC/ON. Our nomogram shows strong efficacy in predicting RION.

Radiotherapy interruption due to holidays adversely affects the survival of patients with nasopharyngeal carcinoma: a joint analysis based on large-scale retrospective data and clinical trials.

BACKGROUND: The impact of radiotherapy interruption due to the Spring Festival holidays in China on the survival of patients with nasopharyngeal carcinoma (NPC) is unclear. METHODS: Nontrial patients with locoregionally advanced NPC receiving radiotherapy plus induction chemotherapy (IC) and/or concurrent chemotherapy (CC) were included (N = 5035) and divided into two groups based on the Spring Festival-induced radiotherapy interruption. Kaplan-Meier curves for overall survival (OS) and failure-free survival (FFS) were compared between rival groups. Impact of the timing of radiotherapy interruption (during or outside the Spring Festival) on survival was investigated in a propensity score-matched dataset. We adopted ordination correspondence analysis to determine the cut-off of radiotherapy prolongation for prognostic prediction, and accordingly performed subgroup analysis based on delayed days and chemotherapy details. Individual patient data of three phase III NPC trials (NCT00677118, NCT01245959, NCT01872962) were used for validation (N = 1465). RESULTS: Radiotherapy interruption was most frequently observed between December to January of the following year. Significantly lower OS and FFS were associated with the Spring Festival-induced interruption of radiotherapy (P = 0.009 and 0.033, respectively), but not that interruption of IC. In two matched comparison groups, the timing of radiotherapy interruption during the Spring Festival was more likely to lead to a decrease in FFS than outside the Spring Festival (P = 0.046), which was not observed in the validation using clinical trial data or in the subgroup analysis based on the 5-day delayed time. The absence of CC and the accumulated dose of cisplatin < 200 mg were related to the negative influences of the Spring Festival-induced radiotherapy interruption on FFS (P = 0.002) and OS (P = 0.010), respectively. CONCLUSIONS: The poor survival of patients with NPC is associated with the Spring Festival-induced interruption of radiotherapy. We recommend that these patients receive adequate doses of cisplatin concurrently with radiotherapy.

Progression-free survival assessed per immune-related or conventional response criteria, which is the better surrogate endpoint for overall survival in trials of immune-checkpoint inhibitors in lung cancer: A systematic review and meta-analysis.

Progression-free survival (PFS) has been used as a surrogate endpoint for overall survival (OS) in lung cancer trials. The pattern of response to immune-checkpoint inhibitors (ICIs) differs from that to conventional chemotherapy, so immune-related response evaluation criteria were proposed. This study aims at determining which PFS measure, PFS assessed per immune-related response evaluation criteria (iPFS), or conventional criteria (cPFS), is the better surrogate endpoint for OS in trials of ICIs in lung cancer. We selected clinical trials in lung cancer that administered ICIs to at least one arm and reported both median OS and median PFS from PubMed, Embase, and The Cochrane Library. We compared the correlation between treatment effect (hazard ratio) on OS and cPFS or iPFS and the correlation between median OS and median cPFS or iPFS using weighted linear regression at trial level. We analyzed 78 ICI arms (13,438 patients) from 54 studies, including 66 arms with cPFS, seven arms with iPFS, and five arms with both kinds of PFS. We demonstrated an excellent correlation between treatment effect (hazard ratio) on OS and iPFS (RWLS2  = 0.91), while the correlation was moderate for cPFS (RWLS2  = 0.38). Similarly, the correlation between median OS and median iPFS was also strong (RWLS2 ranging from 0.86 to 0.96) across different phases of trials and different types of lung cancer, ICI, and treatment modalities, while it was much weaker for median cPFS (RWLS2 ranging from 0.28 to 0.88). In conclusion, iPFS provides better trial-level surrogacy for OS than cPFS in trials of ICIs in lung cancer.

Assessment of Modifiable Factors for the Association of Marital Status With Cancer-Specific Survival.

Importance: Married patients with cancer have better cancer-specific survival than unmarried patients. Increasing the early diagnosis and definitive treatment of cancer among unmarried patients may reduce the survival gap. Objectives: To evaluate the extent to which marriage is associated with cancer-specific survival, stage at diagnosis, and treatment among patients with 9 common solid cancers and to recommend methods for reducing the survival gap. Design, Setting, and Participants: This retrospective, population-based cohort study included patients older than 18 years who were diagnosed with 1 of 9 common cancers between January 1, 2007, and December 31, 2016. Patient data were retrieved from the Surveillance, Epidemiology, and End Results Program. Statistical analyses were performed from August 1 to October 1, 2020. Exposures: Marital status, classified as married and unmarried (including single, separated, divorced, widowed, and unmarried patients or domestic partners). Main Outcomes and Measures: The primary outcome was the time ratio (TR) of cancer-specific survival (married vs unmarried). Mediation analyses were conducted to determine the extent to which the association of marriage with cancer-specific survival was mediated by stage at diagnosis and treatment. Results: This study included 1 733 906 patients (894 379 [51.6%] women; 1 067 726 [61.6%] married; mean [SD] age, 63.76 [12.60] years). Multivariate analyses found that those who were married were associated with better cancer-specific survival than unmarried patients (TR, 1.36; 95% CI, 1.35-1.37). Early diagnosis in breast cancer, colorectal cancer, endometrial cancer, and melanoma mediated the association between marital status and cancer-specific survival (breast cancer: proportion mediated [PM], 11.4%; 95% CI, 11.2%-11.6%; colorectal cancer: PM, 10.9%; 95% CI, 10.7%-11.2%; endometrial cancer: PM, 12.9%; 95% CI, 12.5%-13.3%; melanoma: PM, 12.0%; 95% CI, 11.7-12.4%). Surgery mediated the association between marital status and cancer-specific survival in lung (PM, 52.2%; 95% CI, 51.9%-52.4%), pancreatic (PM, 28.9%; 95% CI, 28.6%-29.3%), and prostate (PM, 39.3%; 95% CI, 39.0%-39.6%) cancers. Chemotherapy mediated the association of marital status with cancer-specific survival in lung (PM, 37.7%; 95% CI, 37.6%-37.9%) and pancreatic (PM, 28.6%; 95% CI, 28.4%-28.9%) cancers. Improved cancer-specific survival associated with marriage was greater among men than women (men: TR, 1.27; 95% CI, 1.25-1.28; women: TR, 1.20; 95% CI, 1.19-1.21). The contribution of receiving an early diagnosis and treatment with surgery or chemotherapy to the association between marital status and cancer-specific survival was greater among men than women (early diagnosis: PM, 21.7% [95% CI, 21.5%-21.9%] vs PM, 20.3% [95% CI, 20.2%-20.4%]; surgery: PM, 26.6% [95% CI, 26.4%-26.7%] vs PM, 11.1% [95% CI, 11.0%-11.2%]; chemotherapy: PM, 6.8% [95% CI, 6.7%-6.8%] vs PM, 5.1% [95% CI, 5.0%-5.2%]). Conclusions and Relevance: In this study, survival disparities associated with marital status were attributable to early diagnosis in breast, colorectal, and endometrial cancers as well as melanoma and to treatment-related variables in lung, pancreatic, and prostate cancers. The findings also suggest that marriage may play a greater protective role in the cancer-specific survival of men than of women.

CUL3 (cullin 3)-mediated ubiquitination and degradation of BECN1 (beclin 1) inhibit autophagy and promote tumor progression.

Macroautophagy/autophagy plays an important role during the development of human cancer. BECN1 (beclin 1), a core player in autophagy regulation, is downregulated in many kinds of malignancy. The underlying mechanism, however, has not been fully illuminated. Here, we found that CUL3 (cullin 3), an E3 ubiquitin ligase, could interact with BECN1 and promote the K48-linked ubiquitination and degradation of this protein; In addition, CUL3 led to a decrease in autophagic activity through downregulating BECN1. We also found that KLHL38 was a substrate adaptor of the CUL3 E3 ligase complex-mediated ubiquitination and degradation of BECN1. In breast and ovarian cancer, CUL3 could promote the proliferation of tumor cells, and the expression of CUL3 was related to poor prognosis in patients. Our study reveals the underlying mechanism of BECN1 ubiquitination and degradation that affects autophagic activity and subsequently leads to tumor progression, providing a novel therapeutic strategy that regulates autophagy to combat cancer.Abbreviations: ATG: autophagy-related BECN1: beclin 1 CHX: cycloheximide CoIP: co-immunoprecipitation CUL3: cullin 3 IP: immunoprecipitation MS: mass spectrometry PtdIns3K: phosphatidylinositol 3-kinase UPS: ubiquitin-proteasome system.

Difference of pain vulnerability in adult and juvenile rodents: the role of SIRT1-mediated ClC-3 trafficking in sensory neurons.

ABSTRACT: Adults are more likely to suffer from chronic pain than minors, and its underlying mechanism remains unclear. SIRT1 an important age-related protein with function of lifespan extension; whether SIRT1 plays a role in the different pain vulnerability of adult and juvenile remains unclear. Here, we found that the expression level of SIRT1 in dorsal root ganglia (DRG) was related to the pain vulnerability. After nerve injury, the expression of SIRT1 in DRG was decreased in adult rodents whereas increased in juvenile rodents. Differential manipulation of SIRT1 abolished the different pain vulnerability between adult and juvenile rodents. Furthermore, SIRT1 interacted with ClC-3 channel and mediated ClC-3 membrane trafficking and Cl- current in DRG neurons. Differential manipulation of ClC-3 also abolished the difference in pain vulnerability between adult and juvenile rodents. The different anti-inflammatory ability determined the different change trends of SIRT1 and ClC-3 trafficking contributed to the different pain vulnerability in adult and juvenile rodents. In addition, the serum SIRT1 level was negatively correlated with the pain score in patients with chronic pain. These findings revealed the mechanism of the difference in pain vulnerability between adult and juvenile rodents and provided evidence for age-specific treatment of chronic pain.

Deposited ultra-thin titanium nitride nanorod array as a plasmonic near-perfect light absorber.

The transmittance, reflectance, and extinctance that correspond to the localized plasmonic resonance within TiN nanorods were investigated. The obliquely deposited TiN nanorod array shows polarization-independent admittance matching to air. Unlike noble metal nanorods, the near-field localized longitudinal and transverse plasmonic resonance of TiN nanorod arrays present polarization-dependent light extinction in the far field. The longitudinal plasmonic mode presents stronger extinction than transverse plasmonic mode. In order to have high efficient light absorption, an ultra-thin two-layered TiN nanorod array was fabricated with orthogonal deposition planes for upper layer and bottom layer to absorb different polarized light energy. The measured spectrum shows broadband and wide-angle light extinction.

p-Dimethylaminobenzaldehyde thiosemicarbazone: a simple novel selective and sensitive fluorescent sensor for mercury(II) in aqueous solution.

A novel and simple fluorophore, p-dimethylaminobenzaldehyde thiosemicarbazone (DMABTS), was prepared in order to find available fluorescent chemosensor for mercuric ion in aqueous solution. DMABTS emitted fluorescence at 448 nm in aqueous solution and its fluorescence intensity was completely quenched upon interaction with Hg(2+) ions, which should be attributed to the 1:1 complex formation between DMABTS and Hg(2+). The binding constant of the complex was determined as 7.48 x 10(6)mol l(-1). The linear range of quantitative detection of 0 to 5.77 x 10(-6)mol l(-1) and the detection limit of 7.7 x 10(-7)mol l(-1) for Hg(2+) in the 6.3 x 10(-6)mol l(-1) DMABTS aqueous solution were obtained from a calibration curve. The coexistence of several transition metal ions and anions did interfere the fluorometric titration of Hg(2+) ion by less than 4% in the emission change.