BACKGROUND: Radiotherapy is the primary treatment for patients with nasopharyngeal carcinoma (NPC); however, almost 20% of patients experience treatment failure due to radioresistance. Therefore, understanding the mechanisms of radioresistance is imperative. HOTAIRM1 is deregulated in various human cancers, yet its role in NPC radioresistance are largely unclear.
METHODS: This study investigated the association between HOTAIRM1 and radioresistance using CCK8, flow cytometry, and comet assays. Additionally, xenograft mice and patient-derived xenografts (PDX) models were employed to elucidate the biological functions of HOTAIRM1, and transcriptomic RNA sequencing was utilized to identify its target genes.
RESULTS: Our study revealed an upregulation of HOTAIRM1 levels in radioresistant NPC cell lines and tissues. Furthermore, a positive correlation was noted between high HOTAIRM1 expression and increased NPC cell proliferation, reduced apoptosis, G2/M cell cycle arrest, and diminished cellular DNA damage following radiotherapy. HOTAIRM1 modulates the acetylation and stability of the FTO protein, and inhibiting FTO elevates the m6A methylation level of CD44 precursor transcripts in NPC cells. Additionally, silencing the m6A reading protein YTHDC1 was found to increase the expression of CD44V. HOTAIRM1 enhances NPC cell resistance to ferroptosis and irradiation through the HOTAIRM1-FTO-YTHDC1-CD44 axis. Mechanistically, HOTAIRM1 interacts with the FTO protein and induces m6A demethylation of the CD44 transcript. The absence of m6A modification in the CD44 transcript prevents its recognition by YTHDC1, resulting in the transition from CD44S to CD44V. An abundance of CD44V suppresses ferroptosis induced by irradiation and contributes to NPC radioresistance.
CONCLUSIONS: In conclusion, the results in this study support the idea that HOTAIRM1 stimulates CD44 alternative splicing via FTO-mediated demethylation, thereby attenuating ferroptosis induced by irradiation and promoting NPC radioresistance.

The nuclear pore complex (NPC) is the sole mediator of nucleocytoplasmic transport. Despite great advances in understanding its conserved core architecture, the peripheral regions can exhibit considerable variation within and between species. One such structure is the cage-like nuclear basket. Despite its crucial roles in mRNA surveillance and chromatin organization, an architectural understanding has remained elusive. Using in-cell cryo-electron tomography and subtomogram analysis, we explored the NPC\'s structural variations and the nuclear basket across fungi (yeast; S. cerevisiae), mammals (mouse; M. musculus), and protozoa (T. gondii). Using integrative structural modeling, we computed a model of the basket in yeast and mammals that revealed how a hub of nucleoporins (Nups) in the nuclear ring binds to basket-forming Mlp/Tpr proteins: the coiled-coil domains of Mlp/Tpr form the struts of the basket, while their unstructured termini constitute the basket distal densities, which potentially serve as a docking site for mRNA preprocessing before nucleocytoplasmic transport.

OBJECTIVE: To investigate the potential of virtual contrast-enhanced MRI (VCE-MRI) for gross-tumor-volume (GTV) delineation of nasopharyngeal carcinoma (NPC) using multi-institutional data.
METHODS: This study retrospectively retrieved T1-weighted (T1w), T2-weighted (T2w) MRI, gadolinium-based contrast-enhanced MRI (CE-MRI) and planning CT of 348 biopsy-proven NPC patients from three oncology centers. A multimodality-guided synergistic neural network (MMgSN-Net) was trained using 288 patients to leverage complementary features in T1w and T2w MRI for VCE-MRI synthesis, which was independently evaluated using 60 patients. Three board-certified radiation oncologists and two medical physicists participated in clinical evaluations in three aspects: image quality assessment of the synthetic VCE-MRI, VCE-MRI in assisting target volume delineation, and effectiveness of VCE-MRI-based contours in treatment planning. The image quality assessment includes distinguishability between VCE-MRI and CE-MRI, clarity of tumor-to-normal tissue interface and veracity of contrast enhancement in tumor invasion risk areas. Primary tumor delineation and treatment planning were manually performed by radiation oncologists and medical physicists, respectively.
RESULTS: The mean accuracy to distinguish VCE-MRI from CE-MRI was 31.67%; no significant difference was observed in the clarity of tumor-to-normal tissue interface between VCE-MRI and CE-MRI; for the veracity of contrast enhancement in tumor invasion risk areas, an accuracy of 85.8% was obtained. The image quality assessment results suggest that the image quality of VCE-MRI is highly similar to real CE-MRI. The mean dosimetric difference of planning target volumes were less than 1Gy.
CONCLUSIONS: The VCE-MRI is highly promising to replace the use of gadolinium-based CE-MRI in tumor delineation of NPC patients.

OBJECTIVE: Patients with recurrent or metastatic nasopharyngeal carcinoma (RM-NPC) have proven benefit from anti-programmed cell death 1 (anti-PD-1) monotherapy. Here, we retrospectively analyze the association of plasma Epstein-Barr virus (EBV) DNA load and tumor viral lytic genome with clinical outcome from 2 registered phase I trials.
METHODS: Patients with RM-NPC from Checkmate 077 (nivolumab phase I trial in China) and Camrelizumab phase I trial between March 2016 and January 2018 were enrolled. Baseline EBV DNA titers were tested in 68 patients and EBV assessment was performed in 60 patients who had at least 3 post-baseline timepoints of EBV data and at least 1 post-baseline timepoint of radiographic assessment. We defined \"EBV response\" as 3 consecutive timepoints of load below 50% of baseline, and \"EBV progression\" as 3 consecutive timepoints of load above 150% of baseline. Whole-exome sequencing was performed in 60 patients with available tumor samples.
RESULTS: We found that the baseline EBV DNA load was positively correlated with tumor size (spearman p < 0.001). Both partial response (PR) and stable disease (SD) patients had significantly lower EBV load than progression disease (PD) patients. EBV assessment was highly consistent with radiographic evaluation. Patients with EBV response had significantly improved overall survival (OS) than patients with EBV progression (log-rank p = 0.004, HR = 0.351 [95% CI: 0.171-0.720], median 22.5 vs. 11.9 months). The median time to initial EBV response and progression were 25 and 36 days prior to initial radiographic response and progression, respectively. Patients with high levels of EBV lytic genomes at baseline, including BKRF2, BKRF3 and BKRF4, had better progression-free survival (PFS) and OS.
CONCLUSIONS: In summary, early clearance of plasma EBV DNA load and high levels of lytic EBV genes were associated with better clinical outcome in patients with RM-NPC receiving anti-PD-1 monotherapy.

This study aimed to investigate whether the RapidPlan (RP) model configured by volumetric modulated arc therapy (VMAT) plans of nasopharyngeal carcinoma (NPC) could be used to assist in the optimization of HT plans and improve their quality. An RP model was trained using 100 clinically accepted VMAT plans of NPC patients. The predicted dose constraints of the VMAT trained RP model were used to reoptimize 25 consecutive clinically accepted HT plans (HT_clinical) and perform new VMAT plans based on the same computed topography (CT). The dosimetric quality of the reoptimized HT plans (HT_reoptimized), HT_clinical, and VMAT group were compared. The minimum dose encompassing 2% target (D2%), the minimum dose encompassing 98% target (D98%), homogeneity index (HI) and conformity index (CI) were similar for most targets between the HT_clinical and HT_reoptimized plans, although certain targets in the HT_reoptimized plans had higher D2% and HI and lower D98%. The HT_reoptimized plans outperformed the HT_clinical plans in the Dmax and D1cc of the spinal cord, V40Gy of the left temporal lobe, Dmean and V30Gy of the oral cavity, Dmean of the larynx and thyroid, and the differences were statistically significant. HT plans had higher CI and HI than VMAT plans. HT plans outperformed VMAT plans in the Dmax of the spinal cord and lenses, V30Gy of the oral cavity and parotids, and V40Gy of the temporal lobes, but underperformed in the Dmax and D1cc of the brainstem, D1cc of the spinal cord and Dmean of the oral cavity. The VMAT-based RP model can be used to assist in the planning of HT plans and improve the dosimetry quality of HT plans.

Autophagy is a critical player in lumbar intervertebral disk degeneration (IDD), and autophagy activation has been suggested to prevent the apoptosis of nucleus pulposus cells (NPCs). Myricetin has anti-cancer, anti-inflammatory, and antioxidant potentials and can activate autophagy. Thus, this study focused on the roles and mechanisms of myricetin in IDD. A puncture-induced rat IDD model was established and intraperitoneally injected with 20-mg/kg/day myricetin. Histopathological changes of intervertebral disks (IVDs) were assessed by hematoxylin and eosin staining and Safranin O/Fast Green staining. The isolated NPCs from IVDs of healthy rats were stimulated with IL-1β to mimic IDD-like conditions. The roles of myricetin in cell apoptosis, extracellular matrix (ECM) degradation, autophagy repression, and the JAK2/STAT3 pathway activation were examined by cell counting kit-8, flow cytometry, western blotting, real-time quantitative polymerase chain reaction, and immunofluorescence staining. Myricetin treatment attenuated the apoptosis and ECM degradation, and enhanced autophagy in the IL-1β-treated NPCs, whereas the myricetin-mediated protection was limited by autophagy inhibition. Mechanistically, myricetin activated autophagy through blocking the JAK2/STAT3 signaling. In vivo experiments revealed that intraperitoneal injection of myricetin activated NPC autophagy to relieve puncture injury in rats. Myricetin prevents IDD by attenuating NPC apoptosis and ECM degradation through blocking the JAK2/STAT3 pathway to enhance autophagy.

Nephron progenitor cells (NPCs) self-renew and differentiate into nephrons, the functional units of the kidney. Here, manipulation of p38 and YAP activity allowed for long-term clonal expansion of primary mouse and human NPCs and induced NPCs (iNPCs) from human pluripotent stem cells (hPSCs). Molecular analyses demonstrated that cultured iNPCs closely resemble primary human NPCs. iNPCs generated nephron organoids with minimal off-target cell types and enhanced maturation of podocytes relative to published human kidney organoid protocols. Surprisingly, the NPC culture medium uncovered plasticity in human podocyte programs, enabling podocyte reprogramming to an NPC-like state. Scalability and ease of genome editing facilitated genome-wide CRISPR screening in NPC culture, uncovering genes associated with kidney development and disease. Further, NPC-directed modeling of autosomal-dominant polycystic kidney disease (ADPKD) identified a small-molecule inhibitor of cystogenesis. These findings highlight a broad application for the reported iNPC platform in the study of kidney development, disease, plasticity, and regeneration.

The pan-immune-inflammation-value (PIV) is a comprehensive biomarker that integrates different peripheral blood cell subsets. The present study aimed to evaluate the prognostic ability of PIV in patients with nasopharyngeal carcinoma (NPC) undergoing chemoradiotherapy. PIV was assessed using the following equation: (Neutrophil count × platelet count × monocyte count)/lymphocyte count. The Kaplan-Meier method and Cox hazards regression models were used for survival analyses. The optimal cut-off values for PIV and systemic immune-inflammation index (SII) were determined using receiver operating characteristic analysis to be 428.0 and 1032.7, respectively. A total of 319 patients were recruited. Patients with a low baseline PIV (≤428.0) accounted for 69.9% (n=223) and patients with a high baseline PIV (>428.0) accounted for 30.1% (n=96). Compared with patients with low PIV, patients with a high PIV had significantly worse 5-year progression-free survival [PFS; 66.8 vs. 77.1%; hazard ratio (HR), 1.97; 95% confidence interval (CI), 1.22-3.23); P=0.005] and 5-year overall survival (OS; 68.7 vs. 86.9%, HR, 2.71; 95% CI, 1.45-5.03; P=0.001). PIV was also a significant independent prognostic indicator for OS (HR, 2.19; 95% CI, 1.16-4.12; P=0.016) and PFS (HR, 1.86; 95% CI, 1.14-3.04; P=0.013) and outperformed the SII in multivariate analysis. In conclusion, the PIV was a powerful predictor of survival outcomes and outperformed the SII in patients with NPC treated with chemoradiotherapy. Prospective validation of the PIV should be performed to better stratify radical treatment of patients with NPC.

The present study aimed to investigate the value of intravoxel incoherent motion imaging (IVIM) and three-dimensional pulsed continuous arterial spin labeling (ASL) in assessing dynamic changes of the parotid gland in patients with nasopharyngeal carcinoma (NPC) following radiotherapy (RT). A total of 18 patients with NPC who underwent intensity-modulated RT were enrolled in the present study. All patients underwent conventional magnetic resonance imaging, plus IVIM and ASL imaging of the bilateral parotid glands within 2 weeks prior to RT, and 1 week (1W) and 3 months (3M) following RT. Pure diffusion coefficient (D), pseudo-diffusion coefficient (D*), perfusion fraction (F) and blood flow (BF) were analyzed. D and BF values were significantly increased from pre-RT to 1W post-RT [change rate: Median (IQR), ΔD1W%: 39.28% (38.23%) and ΔBF1W%: 60.84% (54.88%)] and continued to increase from 1W post-RT to 3M post-RT [55.44% (40.56%) and ΔBF%: 120.39% (128.74%)]. In addition, the F value was significantly increased from pre-RT to 1W post-RT, [change rate: Median (IQR), ΔF1W%: 28.13% (44.66%)], and this decreased significantly from 1W post-RT to 3M post-RT. However, no significant differences were observed between pre-RT and 3M post-RT. Results of the present study also demonstrated that the D* value was significantly decreased from pre-RT to 1W post-RT and 3M post-RT [change rate: Median (IQR), ΔD*1w%: -41.86% (51.71%) and ΔD*3M: -29.11% (42.67%)]. No significant difference was observed between the different time intervals post-RT. There was a significant positive correlation between percentage change in ΔBF1W and radiation dose (ρ=0.548, P=0.001). Thus, IVIM-diffusion-weighted imaging and ASL may aid in the detection and prediction of radiation-induced parotid damage in the early stages following RT. They may contribute to further understanding the potential association between damage to the parotid glands and patient-/treatment-related variables, through the assessment of individual microcapillary perfusion and tissue diffusivity.

OBJECTIVE: This study was designed to assess the efficacy and safety of cadonilimab monotherapy, a first-in-class, bi-specific PD-1/CTLA-4 antibody, in patients with previously treated recurrent or metastatic nasopharyngeal carcinoma (R/M-NPC).
METHODS: This multicenter, open-label, single-arm, phase II clinical trial enrolled patients with R/M-NPC who had failed first-line platinum-based chemotherapy and second-line single agent or combined chemotherapy, and immunotherapy-naive. Patients received cadonilimab for 6 mg/kg once every 2 weeks (Q2W). The primary endpoint was objective response rate (ORR) in full analysis set (FAS) assessed by investigators according to RECIST v.1.1. The secondary endpoint included progression-free survival (PFS), overall survival (OS), duration of response (DoR), time to response (TTR) and safety.
RESULTS: A total of 23 patients were assessed. The median time from first dose to data cutoff was 16.56 (range, 0.8-25.2) months. ORR was 26.1 % (95 %CI:10.2-48.4). The ORR were 44.4 % (95 %CI: 13.7-78.8) and 14.3 % (95 %CI:1.8-42.8) in patients with tumor PD-L1 expression ≥50 % and <50 %, respectively. ORR was achieved in 40.0 % (95 %CI:12.2-73.8) of patients with EBV-DNA level <4000 IU/ml (n = 10) and 15.4 % (95 %CI:1.9-45.4) of those with ≥4000 IU/ml. The median PFS was 3.71 months (95 %CI: 1.84-9.30). respectively. Median OS was not reached, and the 12-month OS rate was 79.7 % (95 % CI:54.5-91.9). Only two patients (8.3 %) experienced Grade ≥3 treatment-related adverse events (TRAEs) with hypothyroidism (30.4 %), rash (21.7 %) and pruritus (21.7 %) being the most prevalent TRAEs.
CONCLUSIONS: Cadonilimab monotherapy demonstrated a promising efficacy and manageable toxicity in patients with previously treated R-M/NPC and provide an efficacious salvage treatment option.