2D Transition Metal Chalcogenides (TMDs) for Electrocatalytic Hydrogen Evolution Reaction: A Review.

Since the MoS2 synthesis, the family of two-dimensional transition metal chalcogenides (TMDs) have been intensively explored theoretically and experimentally. TMDs endowed with adjustable electronic, physical and chemical properties lead to increasing interest in the application of energy storage, molecule detection and catalysis. In the mini review, we present a forward-looking summary of 2D TMDs in hydrogen evolution electrocatalysis, including synthesis methods, hydrogen evolution performance, and optimization strategies. This review will deepen the fundamental understanding of the physical-chemical properties of TMDs with different phases and contribute unveil the universal principle among electronic configuration, atomic arrangement, physical and chemical property for the material design.

Head and neck MRI-based T stage and [18F]FDG PET/CT-based N/M stage improved prognostic stratification in primary nasopharyngeal carcinoma.

OBJECTIVES: To evaluate whether MRI-based T stage (TMRI), [18F]FDG PET/CT-based N (NPET/CT), and M stage (MPET/CT) are superior in NPC patients' prognostic stratification based on long-term survival evidences, and whether TNM staging method involving TMRI + NPET/CT + MPET/CT could improve NPC patients' prognostic stratification. METHODS: From April 2007 to December 2013, 1013 consecutive untreated NPC patients with complete imaging data were enrolled. All patients' initial stages were repeated based on (1) the NCCN guideline recommended "TMRI + NMRI + MPET/CT" ("MMP") staging method; (2) the traditional "TMRI + NMRI + Mconventional work-up (CWU)" ("MMC") staging method; (3) the single-step "TPET/CT + NPET/CT + MPET/CT" ("PPP") staging method; or (4) the "TMRI + NPET/CT + MPET/CT" ("MPP") staging method recommended in present research. Survival curve, ROC curve, and net reclassification improvement (NRI) analysis were used to evaluate the prognosis predicting ability of different staging methods. RESULTS: [18F]FDG PET/CT performed worse on T stage (NRI = - 0.174, p < 0.001) but better on N (NRI = 0.135, p = 0.004) and M stage (NRI = 0.126, p = 0.001). The patients whose N stage upgraded by [18F]FDG PET/CT had worse survival (p = 0.011). The "TMRI + NPET/CT + MPET/CT" ("MPP") method performed better on survival prediction when compared with "MMP" (NRI = 0.079, p = 0.007), "MMC" (NRI = 0.190, p < 0.001), or "PPP" method (NRI = 0.107, p < 0.001). The "TMRI + NPET/CT + MPET/CT" ("MPP") method could reclassify patients' TNM stage to a more appropriate stage. The improvement is significant in patients with more than 2.5-years follow-up according to the time-dependent NRI values. CONCLUSIONS: The MRI is superior to [18F]FDG PET/CT in T stage, and [18F]FDG PET/CT is superior to CWU in N/M stage. The "TMRI + NPET/CT + MPET/CT" ("MPP") staging method could significantly improve NPC patients' long-term prognostic stratification. CLINICAL RELEVANCE STATEMENT: The present research provided long-term follow-up evidence for benefits of MRI and [18F]FDG PET/CT in TNM staging for nasopharyngeal carcinoma, and proposes a new imaging procedure for TNM staging incorporating MRI-based T stage and [18F]FDG PET/CT-based N and M stage, which significantly improves long-term prognostic stratification for patients with NPC. KEY POINTS: • The long-term follow-up evidence of a large-scale cohort was provided to evaluate the advantages of MRI, [18F]FDG PET/CT, and CWU in the TNM staging of nasopharyngeal carcinoma. • A new imaging procedure for TNM stage of nasopharyngeal carcinoma was proposed.

Interfacial melting mechanism of nanocrystals determined by interfacial energy and interfacial stress.

To clarify the interface melting mechanism, a unified analytical expression was developed to describe the depression and superheating of Tm(D) functions for metallic nanoparticles, nanostructures, and nanoparticles embedded in a coherent or incoherent interface. Tm(D) functions are determined by the sign of γss, fss (or γsl and fsl), and D0 as caused by the change of interface environments. We found that there is TCIm(D) > TNSm(D) > TIIm(D) > TNPsm(D) for Ag nanocrystals within different interfaces. Moreover, for a given size, Tm(D)/Tm(∞) decreases with the reduction of γss/fss for nanoparticles, nanostructures and nanoparticles embedded in incoherent interfaces, while an opposite trend occurs for the coherent interfaces. In addition, we also found that there is TNPsm(D)/Tm(∞) < TIIm(D)/Tm(∞) < TNSm(D)/Tm(∞), which is in agreement with the relation of γNPssl/fNPssl < γIIss/fIIss < γNSss/fNSss. By analyzing the γss(D) (or γsl(D)), fss(D) (or fsl(D)) and γss(D)/fss(D) (or γsl(D)/fsl(D)) functions of Ag nanocrystals and comparing with their Tm(D) functions, it is found that there is a high consistency between the variation of γss(D)/fss(D) (γsl(D)/fsl(D)) and Tm(D)/Tm, which reveals that the size dependence of Tm(D)/Tm is determined by γss(D)/fss(D) (or γsl(D)/fsl(D)). Our predictions show a good agreement with the available theoretical and experimental results.

Nomogram for the prediction of primary distant metastasis of nasopharyngeal carcinoma to guide individualized application of FDG PET/CT.

PURPOSE: This study aimed to establish an effective nomogram to predict primary distant metastasis (DM) in patients with nasopharyngeal carcinoma (NPC) to guide the application of PET/CT. METHODS: In total, 3591 patients with pathologically confirmed NPC were consecutively enrolled. The nomogram was constructed based on 1922 patients treated between 2007 and 2014. Multivariate logistical regression was applied to identify the independent risk factors of DM. The predictive value of the nomogram was evaluated using the concordance index (C-index), calibration curve, probability density functions (PDFs), and clinical utility curve (CUC). The results were validated in 1669 patients enrolled from 2015 to 2016. Net reclassification improvement (NRI) was applied to compare performances of the nomogram with other clinical factors. The best cut-off value of the nomogram chosen for clinical application was analyzed. RESULTS: A total of 355 patients showed primary DM among 3591 patients, yielding an incidence rate of 9.9%. Sex, N stage, EBV DNA level, lactate dehydrogenase level, and hemoglobin level were independent predictive factors for primary DM. C-indices in the training and validation cohort were 0.796 (95% CI, 0.76-0.83) and 0.779 (95% CI, 0.74-0.81), respectively. The NRI indices demonstrated that this model had better predictive performance than plasma EBV DNA level and N stage. We advocate for a threshold probability of 3.5% for guiding the application of PET/CT depending on the clinical utility analyses. CONCLUSION: This nomogram is a useful tool to predict primary DM of NPC and guide the clinical application of PET/CT individually at the initial staging.

Subdivision of de-novo metastatic nasopharyngeal carcinoma based on tumor burden and pretreatment EBV DNA for therapeutic guidance of locoregional radiotherapy.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a malignancy predominantly associated with infection by the Epstein-Barr virus (EBV). Approximately 12,900 new cases of NPC occur each year, with more than 70% of cases occurring in the east and southeast Asia. NPC is different from ordinary head and neck squamous cell carcinoma due to its particular biological properties and it is highly sensitive to radiotherapy. With the development of RT technology, the 3-year local control rate and survival rates of non-metastatic NPC reached 80-90% in the intensity-modulated RT (IMRT) era. However, whether distant metastatic NPC (de novo mNPC, dmNPC) should receive locoregional RT (LRRT) needs to be clarified. RESULTS: Multivariate analysis identified three independent prognostic factors: Epstein-Barr virus (EBV) DNA, number of metastatic lesions, and number of metastatic organs. Through these factors, all patients were successfully divided into 3 subgroups: low-risk (single metastatic organ, EBV DNA ≤ 25,000 copies/ml, and ≤ 5 metastatic lesions), intermediate-risk (single metastatic organ, EBV DNA > 25,000 copies/ml, and ≤ 5 metastatic lesions), and high-risk (multiple metastatic organs or > 5 metastatic lesions or both). By comparing LRRT and non-LRRT groups, statistical differences were found in OS in the low-risk and intermediate-risk subgroups (p = 0.039 and p = 0.010, respectively) but no significant difference was found in OS in the high-risk subgroup (p = 0.076). Further multivariate analysis of different risk stratifications revealed that LRRT can improve OS of low- and intermediate-risk subgroups. CONCLUSIONS: The risk stratification of dmNPC may be used as a new prognostic factor to help clinicians organize individualized LRRT treatment to improve the survival outcomes of dmNPC patients.

Low value of whole-body dual-modality [18f]fluorodeoxyglucose positron emission tomography/computed tomography in primary staging of stage I-II nasopharyngeal carcinoma: a nest case-control study.

OBJECTIVES: The value of using PET/CT for staging of stage I-II NPC remains unclear. Hence, we aimed to investigate the survival benefit of PET/CT for staging of early-stage NPC before radical therapy. METHODS: A total of 1003 patients with pathologically confirmed NPC of stages I-II were consecutively enrolled. Among them, 218 patients underwent both PET/CT and conventional workup ([CWU], head-and-neck MRI, chest radiograph, liver ultrasound, bone scintigraphy) before treatment. The remaining 785 patients only underwent CWU. The standard of truth (SOT) for lymph node metastasis was defined by the change of size according to follow-up MRI. The diagnostic efficacies were compared in 218 patients who underwent both PET/CT and CWU. After covariate adjustment using propensity scoring, a cohort of 872 patients (218 with and 654 without pre-treatment PET/CT) was included. The primary outcome was overall survival based on intention to treat. RESULTS: Retropharyngeal lymph nodes were metastatic based on follow-up MRI in 79 cases. PET/CT was significantly less sensitive than MRI in detecting retropharyngeal lymph node lesions (72.2% [62.3-82.1] vs. 91.1% [84.8-97.4], p = 0.004). Neck lymph nodes were metastatic in 89 cases and PET/CT was more sensitive than MRI (96.6% [92.8-100.0] vs. 76.4% [67.6-85.2], p < 0.001). In the survival analyses, there was no association between pre-treatment PET/CT use and improved overall survival, progression-free survival, local relapse-free survival, regional relapse-free survival, and distant metastasis-free survival. CONCLUSIONS: This study showed PET/CT is of little value for staging of stage I-II NPC patients at initial imaging. KEY POINTS: • PET/CT was more sensitive than MRI in detecting neck lymph node lesions whereas it was significantly less sensitive than MRI in detecting retropharyngeal lymph node lesions. • No association existed between pre-treatment PET/CT use and improved survival in stage I-II NPC patients.

Stabilization of 4E-BP1 by PI3K kinase and its involvement in CHK2 phosphorylation in the cellular response to radiation.

Objectives: 4E-BP1 is a family member of eIF4E binding proteins (4E-BPs) which act as the suppressors of cap-dependent translation of RNA via competitively associating with cap-bound eIF4E. RNA translation regulation is an important manner to control the cellular responses to a series of stress conditions such as ionizing radiation (IR)-induced DNA damage response and cell cycle controlling. This study aimed to determine the mechanism of 4E-BP1 stabilization and its potential downstream target(s) in the response to IR. Methods: PI3Ks kinase inhibitors were used to determine the signaling control of 4E-BP1 phosphorylation and protein stability. shRNA strategy was employed to silence the expression of 4E-BP1 in HeLa and HepG2 cells, and determine its effect on the irradiation-induced CHK2 phosphorylation. The protein degradation/stability was investigated by western blotting on the condition of blocking novel protein synthesis by cycloheximide (CHX). Results: The phosphorylation of 4E-BP1 at Thr37/46 was significantly increased in both HepG2 and HeLa cells by ionizing radiation. Depression of 4E-BP1 by shRNA strategy resulted in an incomplete G2 arrest at the early stage of 2 hours post-irradiation, as well as a higher accumulation of mitotic cells at 10 and 12 hours post-irradiation as compared to the control cells. Consistently, the CHK2 phosphorylation at Thr68 induced by IR was also attenuated by silencing 4E-BP1 expression. Both PI3K and DNA-PKcs kinase inhibitors significantly decreased the protein level of 4E-BP1, which was associated with the accelerated degradation mediated by ubiquitination-proteasome pathway. Conclusion: PI3K kinase activity is necessary for maintaining 4E-BP1 stability. Our results also suggest 4E-BP1 a novel biological role of regulating cell cycle G2 checkpoint in responding to IR stress in association with controlling CHK2 phosphorylation.

The prognostic value of pretreatment 18F-FDG PET-CT parameters with peripheral blood markers in patients with de novo metastatic nasopharyngeal carcinoma.

BACKGROUND AND PURPOSE: To develop and validate a prognostic nomogram based on pretreatment 18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET-CT)radiomics parameters and peripheral blood markers for risk stratification in patients with de novo metastatic nasopharyngeal carcinoma (dmNPC). MATERIALS AND METHODS: A total of 558 patients with dmNPC were retrospectively enrolled between 2011 and 2019. Eligible patients were randomly divided into training and validation cohorts (7:3 ratio). A Cox regression model was used to identify prognostic factors for overall survival (OS). The predictive accuracy and discriminative ability of the prognostic nomogram were determined using the concordance index (C-index) and calibration curve. RESULTS: Independent factors derived from multivariable analysis of the training cohort to predict death were lactate dehydrogenase levels, pretreatment Epstein-Barr virus DNA, total lesion glycolysis of locoregional lesions, number of metastatic lesions, and age, all of which were assembled into a nomogram with (nomogram B) or without PET-CT parameters (nomogram A). The C-index of nomogram B for predicting death was 0.70, which was significantly higher than the C-index values for nomogram A. Patients were then stratified into low- and high-risk groups based on the scores calculated using nomogram B for OS. The median OS was significantly higher in the low-risk group than in the high-risk group (69.60 months [95 % CI: 58.50-108.66] vs. 21.40 months [95 % CI: 19.20-23.90]; p＜0.01). All the results were confirmed in the validation cohort. CONCLUSION: The proposed nomogram including PET-CT parameters yielded accurate prognostic predictions for patients with dmNPC, enabling effective risk stratification for these patients.

Substrate Strain Engineering of Single-Atomic Sn-N4 Sites Embedded in Various Carbon Matrixes for Bifunctional Oxygen Electrocatalysis.

It is still a great challenge to design and synthesize high-efficiency and low-cost single-atom catalysts (SACs) as promising bifunctional electrocatalysts for the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER). Herein, theoretical insights into Sn-N4 embedded carbon nanotubes, graphene quantum dots, and graphene nanosheets (denoted as Sn-N4-CNTs, Sn-N4-GQDs, and Sn-N4-Gra, respectively) for the ORR/OER are systematically provided. These results show that the protruding Sn atom creates a Sn-N4 pyramid and induces varied strain transfer between Sn-N4 and different carbon substrates prior to adsorption of O intermediates, resulting in the opposite response of the adsorption strengths of O intermediates to the substrate curvature of Sn-N4-CNTs and Sn-N4-GQDs. The torsional strain induced by OH* and OOH* on the Sn atom of Sn-N4-CNTs breaks the scaling relations between the adsorption strengths of O intermediates. Consequently, Sn-N4-CNTs with suitable curvature achieve outstanding ORR performance with very low overpotentials (0.28 V). Furthermore, the increase of curvature boosts the OER activity of Sn-N4-CNTs. For Sn-N4-GQDs, high curvature contributes to promoted OER activity but reduced ORR activity. The electronic interactions reveal the electron transfer from the s/p-bands of Sn to the half-filled ß states of the frontier orbitals of O intermediates.

Development and validation of a transcriptomics-based gene signature to predict distant metastasis and guide induction chemotherapy in locoregionally advanced nasopharyngeal carcinoma.

AIM: Metastasis is the primary cause of treatment failure in nasopharyngeal carcinoma (NPC); however, the current tumour-node-metastasis staging system has limitations in predicting distant metastasis and guiding induction chemotherapy (IC) application. Here, we established a transcriptomics-based gene signature to assess the risk of distant metastasis and guide IC in locoregionally advanced NPC. METHODS: Transcriptome sequencing was performed on NPC biopsy samples from 12 pairs of patients with different metastasis risks. Bioinformatics and qPCR were used to identify differentially expressed genes (DEGs), while univariate and multivariate analyses were used to select prognostic indicators for the gene signature. A signature-based nomogram was established in a training cohort (n = 191) and validated in an external cohort (n = 263). RESULTS: Eleven DEGs were identified between metastatic and non-metastatic NPC. Four of these (AK4, CPAMD8, DDAH1 and CRTR1) were used to create a gene signature that effectively categorised patients into low- and high-risk metastasis groups (training: 91.1 versus 70.4%, p < 0.0001, C-index = 0.752; validation: 88.4 versus 73.9%, p = 0.00057, C-index = 0.741). IC with concurrent chemoradiotherapy (CCRT) improved distant metastasis-free survival in low-risk patients (94.4 versus 85.0%, p = 0.043), whereas patients in the high-risk group did not benefit from IC (72.6 versus 74.9%, p = 0.946). CONCLUSIONS: Our transcriptomics-based gene signature was able to reliably predict metastasis in locoregionally advanced NPC and could be used to identify candidates that could benefit from IC + CCRT.

Development and validation of a normal tissue complication probability model for acquired nasal cavity stenosis and atresia after radical radiotherapy for nasopharyngeal carcinoma.

PURPOSE: Curative radiotherapy for nasopharyngeal carcinoma (NPC) can lead to acquired nasal cavity stenosis and atresia (ANCSA). As the first study to investigate risk factors of ANCSA in a large cohort of NPC patients, this article aims to develop and validate a multivariate normal tissue complication probability (NTCP) model to predict the development of ANCSA and to establish a nomogram for clinical use. METHODS AND MATERIALS: The retrospective cohort was comprised of 548 NPC patients treated with radical radiotherapy. The cohort was randomly divided into training and validation groups. Least absolute shrinkage and selection operator regression was performed for variable selection from the clinical and dosimetric characteristics in the training group. A multivariate NTCP model and a nomogram were established for the prediction of ANCSA development. Discrimination and calibration were tested using receiver operating characteristic (ROC) curves and calibration tests, respectively, for both groups. RESULTS: ANCSA was observed in 132 (24.1%) of 548 patients with NPC who underwent radical radiotherapy. The median time to ANCSA detection after treatment was 2.8 months (range, 0.0-57.7 months). Five potential predictors, including choanal invasion, low white blood cell count, high C-reactive protein level, high serum amyloid A level, and high V70Gy of the nasal cavity, were selected to develop the NTCP model based on 365 patients in the training group. The model had a fairly good discriminative power according to the ROC analysis in both the training (area under ROC curve = 0.79, 95%CI: 0.73-0.84) and validation (0.73, 0.64-0.82) groups. The calibration power was tested using the calibration test in the training (E-max = 0.069, E-avg = 0.015, p = 0.977) and validation (E-max = 0.057, E-avg = 0.032, p = 0.747) groups. CONCLUSIONS: We developed and successfully validated an NTCP model for early prediction of ANCSA in patients with NPC after radical radiotherapy. This could help clinicians assess the risk of ANCSA before the initiation of follow-ups and ensure appropriate and timely management of this complication.

Establishment and validation of a prognostic nomogram to predict early metastasis in nasopharyngeal carcinoma patients within six months after radiotherapy and to guide intensive treatment.

PURPOSE: This study aimed to establish an effective prognostic nomogram to predict the risk of early metastasis (EM) in nasopharyngeal carcinoma (NPC) patients, as a guide for intensive treatment. MATERIALS AND METHODS: A total of 9021 patients with biopsy-confirmed NPC at our institute were enrolled in this study between December 2006 to December 2016. We randomized these patients using a proportion of 2/3 and 1/3 and selected 6044 and 2977 patients as the training and validation cohorts, respectively. All patients received radiotherapy with or without chemotherapy. Univariate and multivariate logistical regressions were used to identify independent risk factors. The nomogram's predictive value was evaluated by concordance indexes (C-indexes), calibration curves, probability density functions (PDFs), and clinical utility curves (CUCs). ROC analysis using Delong test was used to compare efficiency between the nomogram and other risk factors. RESULTS: In total, 174 (2.9%) and 81 (2.7%) patients in training and validation cohorts, respectively, had EM. Pretreatment plasma EBV DNA, N stage, LDH, ALP, BMI, and sex were independent predictive factors of EM. The C-indexes of nomogram were 0.756 (95% CI = 0.719-0.793) and 0.766 (95% CI = 0.720-0.813), in the training and validation cohorts, respectively. The C-index of the nomogram was significantly superior to any one of independent factors. According to the PDFs and CUCs and considering the balance of the true positive EM patients and true positive non-EM patients, we chose 5.0% as a threshold probability for clinical decision-making, which could distinguish about 85% and 48% of non-EM and EM patients, respectively. CONCLUSION: Our nomogram had good accuracy in predicting EM incidence, and a 5.0% threshold was appropriate for clinical decision-making.

Establishment and validation of a nomogram for predicting the benefit of concurrent chemotherapy in stage II nasopharyngeal carcinoma: A study based on a phase III randomized clinical trial with 10-year follow-up.

BACKGROUND AND PURPOSE: Our previous phase III randomized trial demonstrated that the addition of concurrent chemotherapy to radiotherapy (RT) could improve survival in stage II nasopharyngeal carcinoma (NPC). Based on the study, we sought to develop a nomogram for predicting the 5-year and 10-year survival of patients with stage II NPC and estimating the benefit of concurrent chemoradiotherapy (CCRT) for individual patients. MATERIALS AND METHODS: Data of 199 enrolled patients from the original trial was analyzed to build a nomogram. Overall survival (OS) was the primary endpoint. The discrimination and calibration capacities were evaluated using Harrell Concordance Index (C-index) and calibration curves, respectively. Internal validation of the nomogram was performed by a separate cohort of 306 patients from the same cancer center. RESULT: In training cohort, patients in CCRT group achieved higher 5-year and 10-year OS compared with patients in RT group. Three independent prognostic factors, which were age, N stage and treatment method from multivariable analysis were extracted to enter the nomogram. T stage was also included due to its importance in clinical decisions. The Harrell C-index of the nomogram in training and validation cohort was 0.748 and 0.653 respectively. The calibration curves showed an acceptable agreement between prediction and observed probability. CONCLUSION: We developed and validated a nomogram to predict the 5-year and 10-year OS in stage II NPC patients. The nomogram could serve as a pragmatic tool in clinical decisions to estimate the individual risk of stage II patients and identify those who could benefit from chemotherapy.

Establishment and validation of two nomograms to predict the benefit of concurrent chemotherapy in stage II-IVa nasopharyngeal carcinoma patients with different risk factors: Analysis based on a large cohort.

OBJECTIVE: We aimed to establish and validate two nomograms that predict progression-free survival (PFS) and overall survival (OS) in patients with stage II-IVa nasopharyngeal carcinoma (NPC) while evaluating the benefit of concurrent chemotherapy. PATIENTS AND METHODS: We randomly divided 3412 patients newly diagnosed with stage II-IVa NPC between 2008 and 2013 into training and validation 'A' cohorts (n = 1706 each). Another set of patients diagnosed between 2014 and 2016 served as validation cohort 'B' (n = 1503). A Cox multivariate model using the backward stepwise approach was applied to develop the nomograms, which were assessed for accuracy (Harrel C index) and calibration. RESULTS: The 3- and 5-year PFS rates in the training cohort were 86.8% (95% confidence interval [CI] 85.0%-88.6%) and 82.3% (95% CI 80.1%-84.5%), respectively. For the PFS nomogram, 5 variables were selected based on a backward procedure in the multivariate Cox model (gender, T stage, N stage, Epstein-Barr virus DNA, and treatment method). The same variables plus patient age and diabetes mellitus were used for the OS nomogram. The Harrell C indices of the training, validation A, and validation B cohorts were 0.711, 0.700, and 0.703, respectively, for PFS, and 0.775, 0.743, and 0.727, respectively, for OS. Both nomograms performed well in terms of calibration in the training and validation cohorts. CONCLUSIONS: Our nomograms are reliable prognostic predictors of PFS and OS in patients with stage II-IVa NPC. These nomograms could robustly estimate an individual's benefit from concurrent chemotherapy, which assists in treatment decision-making.

Stratification of Candidates for Induction Chemotherapy in Stage III-IV Nasopharyngeal Carcinoma: A Large Cohort Study Based on a Comprehensive Prognostic Model.

Objective: To establish a prognostic index (PI) for patients with stage III-IV nasopharyngeal carcinoma (NPC) patients to personalize recommendations for induction chemotherapy (IC) before intensity-modulated radiotherapy (IMRT). Patients and Methods: Patients received concurrent chemoradiotherapy (CCRT) with or without IC. Factors used to construct the PI were selected by a multivariate analysis of progression-free survival (PFS), which was the primary endpoint (P < 0.05). Five variables were selected based on a backward procedure in a Cox proportional hazards model: gender, T stage, N stage, lactate dehydrogenase (LDH), and Epstein-Barr virus (EBV) DNA. The cutoff value for the PI was determined by the receiver operating characteristic curve analysis. Results: The present study involved 3,586 patients diagnosed with stage III-IV NPC. The cutoff value for PI was 0.8. The high-risk subgroup showed worse outcomes than did the low-risk subgroup on all endpoints: PFS, overall survival (OS), locoregional relapse-free survival (LRFS), and distant metastasis-free survival (DMFS). In the low-risk subgroup (PI <0.8), patients showed comparable survival outcomes on all clinical endpoints regardless of IC application, whereas in the high-risk subgroup (PI > 0.8), the addition of IC significantly improved PFS, OS, and DMFS, but not LRFS. In multivariate analyses, IC was a protective factor for PFS, OS, and DMFS in the high-risk subgroup, while it had no significant benefit in the low-risk subgroup. Conclusion: The proposed prognostic model effectively stratifies patients with stage III-IV NPC. High-risk patients are candidates for IC before CCRT, while low-risk patients are unlikely to benefit from it.

Development and validation of the immune signature to predict distant metastasis in patients with nasopharyngeal carcinoma.

BACKGROUND: The tumor immune microenvironment has clinicopathological significance in predicting prognosis and therapeutic efficacy. We aimed to develop an immune signature to predict distant metastasis in patients with nasopharyngeal carcinoma (NPC). METHODS: Using multiplexed quantitative fluorescence, we detected 17 immune biomarkers in a primary screening cohort of 54 NPC tissues presenting with/without distant metastasis following radical therapy. The LASSO (least absolute shrinkage and selection operator) logistic regression model used statistically significant survival markers in the training cohort (n=194) to build an immune signature. The prognostic and predictive accuracy of it was validated in an external independent group of 304 patients. RESULTS: Eight statistically significant markers were identified in the screening cohort. The immune signature consisting of four immune markers (PD-L1+ CD163+, CXCR5, CD117) in intratumor was adopted to classify patients into high and low risk in the training cohort and it showed a high level of reproducibility between different batches of samples (r=0.988 for intratumor; p<0.0001). High-risk patients had shorter distant metastasis-free survival (HR 5.608, 95% CI 2.619 to 12.006; p<0.0001) and progression-free survival (HR 2.798, 95% CI 1.498 to 5.266; p=0·001). The C-indexes which reflected the predictive capacity in training and validation cohort were 0.703 and 0.636, respectively. Low-risk patients benefited from induction chemotherapy plus concurrent chemoradiotherapy (IC+CCRT) (HR 0.355, 95% CI 0.147 to 0.857; p=0·021), while high-risk patients did not (HR 1.329, 95% CI 0.543 to 3.253; p=0·533). To predict the individual risk of distant metastasis, nomograms with the integration of both immune signature and clinicopathological risk factors were developed. CONCLUSIONS: The immune signature provided a reliable estimate of distant metastasis risk in patients with NPC and might be applied to identify the cohort which benefit from IC+CCRT.

Synthesis and evaluation of chalcone analogues containing a 4-oxoquinazolin-2-yl group as potential anti-tumor agents.

The chalcone motif can be found in many molecules that contribute to essential biological processes, and many chalcone-containing compounds exhibit potent anti-cancer activity. Here, we synthesized two series of chalcone analogues (3a-s and 6a-s) based on substituting the chalcone B-ring or A-ring with a 4-oxoquinazolin-2-yl group, and then evaluated them for cytotoxic activity in human colorectal HCT-116 and breast cancer MCF-7 cell lines. Compounds 3a-s (in which a 4-oxoquinazolin-2-yl group functioned as the B-ring) were markedly more cytotoxic than compounds 6a-s (in which 4-oxoquinazolin-2-yl group functioned as the A-ring), based on their IC50 values to inhibit proliferation. Compound 3f was found as the most potent among 38 analogues and the mechanism of its cytotoxicity was investigated. Flow cytometry indicated that HCT-116 cells treated with compound 3f resulted in a dose-dependent accumulation of cells in the sub-G1 phase, which is representative of apoptotic cells. Subsequent assays (including Annexin V-FITC/PI, AO-EB, MitoSOX™ Red and JC-1 staining) confirmed that 3f exposure induced apoptosis in HCT-116 cells. Immunoblotting analysis indicated that cellular exposure to 3f increased the cleavage of PARP1 and caspases 3, 7, and 9. Taken together, this novel chalcone analogue has a cytotoxic effect on cultured cancer cell-lines that is likely mediated by inducing apoptosis via the mitochondrial death pathway.

Optimal cumulative cisplatin dose in nasopharyngeal carcinoma patients based on induction chemotherapy response.

BACKGROUND AND PURPOSE: Nasopharyngeal carcinoma (NPC) patients can be separated into two risk subgroups according to tumor responses to induction chemotherapy (IC). We aimed to elucidate the optimal cumulative cisplatin dose (CCD) of concurrent chemoradiotherapy (CCRT) for different NPC patient subgroups. PARTICIPANTS AND METHODS: A total of 990 patients with incident NPC diagnosed between 2008 and 2017 treated with IC plus CCRT were included in our observational study. The clinicopathological features of patients with different tumor responses were compared using the Chi-square test or Fisher's exact test. Prognosis was assessed using a multivariate Cox proportional hazards model. In addition, acute and late toxicities were compared between different CCD groups. RESULTS: After IC, 761/990 (76.9%) patients had a complete tumor response (CR)/partial response (PR) and 229 (23.1%) had stable disease (SD)/disease progression (PD). An unsatisfactory tumor response (SD/PD) after IC correlated with poor clinical outcome (3-year PFS 61.4% vs. 83.2%, P < 0.001 and 3-year LRFS 80.9% vs. 94.5%, P < 0.001). Patients who achieved CR/PR after IC received a CCD >200 mg/m2 and showed higher 3-year PFS and DMFS rates than those receiving a CCD <100 mg/m2 (PFS: 85.4% vs. 77.9%, P = 0.045; DMFS: 89.4% vs. 77.9%, P = 0.015). Multivariate analysis also showed that CCD was an independent prognostic factor for PFS and DMFS in CR/PR subgroup. Moreover, the medium dose group showed similar efficacy as high dose group but was associated with fewer grade 1-4 acute toxicities. However, application of different CCD didn't result in significantly different survival outcomes in SD/PD subgroup. CONCLUSIONS: Tumor response to IC was an independent prognostic factor for patients with NPC. For the patients who achieved CR/PR after IC, patients receiving high CCD showed significantly improved 3-year PFS and DMFS compared with patients receiving low CCD. Balancing toxicity and efficacy, 200 mg/m2 seemed to be the optimal dose in the CR/PR groups. However, enhancement of CCD did not provide survival benefit for patients who achieved SD/PD after IC, and treatment options for these patients require further consideration.

Hydroxylated-Graphene Quantum Dots Induce DNA Damage and Disrupt Microtubule Structure in Human Esophageal Epithelial Cells.

Graphene quantum dots (GQDs) have attracted significant interests due to their unique chemical and physical properties. In this study, we investigated the potential effects of hydroxyl-modified GQDs (OH-GQDs) on the human esophageal epithelial cell line HET-1A. Our data revealed significant cytotoxicity of OH-GQDs which decreased the viability of HET-1A in a dose and time-dependent manner. The moderate concentration (25 or 50 µg/ml) of OH-GQDs significantly blocked HET-1A cells in G0/G1 cell cycle phase. An increased percentage of γH2AX-positive and genomically unstable cells were also detected in cells treated with different doses of OH-GQDs (25, 50, and 100 µg/ml). Microarray data revealed that OH-GQDs treatment down-regulated genes related to DNA damage repair, cell cycle regulation and cytoskeleton signal pathways indicating a novel role of OH-GQDs. Consistent with the microarray data, OH-GQDs disrupted microtubule structure and inhibited microtubule regrowth around centrosomes in HET-1A cells. In conclusion, our findings provide important evidence for considering the application of OH-GQDs in biomedical fields.

PIG3 promotes NSCLC cell mitotic progression and is associated with poor prognosis of NSCLC patients.

BACKGROUND: Non-small cell lung cancer (NSCLC) is the most commonly diagnosed type of lung cancer that is associated with poor prognosis. In this study we explored the potential role of p53-induced gene 3 (PIG3) in the progression of NSCLC. METHODS: Immunohistochemistry was used to determine the expression levels of PIG3 in 201 NSCLC patients. We performed in vitro studies and silenced endogenous PIG3 by using specific siRNAs that specific target PIG3. Immunofluorescent staining was performed to determine the effect of PIG3 on mitotic progression in NSCLC cells. The growth rates of microtubules were determined by microtubule nucleation analysis. Cell proliferation and chemosensitivity were analyzed by CCK8 assays. Annexin V staining and ß-galactosidase activity analysis were used to evaluate PIG3 deficiency-related apoptosis and senescence, respectively. RESULTS: PIG3 expression levels negatively correlated with overall survival and disease-free survival of NSCLC patients. Knock down of PIG3 resulted in repressed proliferation of NSCLC cells and increased aberrant mitosis, which included misaligning and lagging chromosomes, and bi- or multi-nucleated giant cells. In addition, PIG3 contributed to mitotic spindle assembly by promoting microtubule growth. Furthermore, loss of PIG3 sensitized NSCLC cells to docetaxel by enhancing docetaxel-induced apoptosis and senescence. CONCLUSIONS: Our results indicate that PIG3 promotes NSCLC progression and therefore suggest that PIG3 may be a potential prognostic biomarker and novel therapeutic target for the treatment of NSCLC.