GO promotes detoxification of nicosulfuron in sweet corn by enhancing photosynthesis, chlorophyll fluorescence parameters, and antioxidant enzyme activity

Although graphene oxide (GO) has extensive recognized application prospects in slow-release fertilizer, plant pest control, and plant growth regulation, the incorporation of GO into nano herbicides is still in its early stages of development. This study selected a pair of sweet corn sister lines, nicosulfuron (NIF)-resistant HK301 and NIF-sensitive HK320, and sprayed them both with 80 mg kg-1 of GO-NIF, with clean water as a control, to study the effect of GO-NIF on sweet corn seedling growth, photosynthesis, chlorophyll fluorescence, and antioxidant system enzyme activity. Compared to spraying water and GO alone, spraying GO-NIF was able to effectively reduce the toxic effect of NIF on sweet corn seedlings. Compared with NIF treatment, 10 days after of spraying GO-NIF, the net photosynthetic rate (A), stomatal conductance (Gs), transpiration rate (E), photosystem II photochemical maximum quantum yield (Fv/Fm), photochemical quenching coefficient (qP), and photosynthetic electron transfer rate (ETR) of GO-NIF treatment were significantly increased by 328.31%, 132.44%, 574.39%, 73.53%, 152.41%, and 140.72%, respectively, compared to HK320. Compared to the imbalance of redox reactions continuously induced by NIF in HK320, GO-NIF effectively alleviated the observed oxidative pressure. Furthermore, compared to NIF treatment alone, GO-NIF treatment effectively increased the activities of superoxide dismutase (SOD), guaiacol peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) in both lines, indicating GO induced resistance to the damage caused by NIF to sweet corn seedlings. This study will provides an empirical basis for understanding the detoxification promoting effect of GO in NIF and analyzing the mechanism of GO induced allogeneic detoxification in cells.

A comprehensive analysis of LINC00958 as a prognostic biomarker for head and neck squamous cell carcinoma

This work focused on exploring whether the long intergenic non-protein coding RNA LINC00958 is associated with the prognosis of head and neck squamous cell carcinoma (HNSCC). Associations of the LINC00958 expression level with clinicopathological features of HNSCC were investigated by logistic regression and Wilcoxon signed-rank test. The Kaplan-Meier method was applied to evaluate patient survival. Clinical data and expression profiles were obtained from The Cancer Genome Atlas (TCGA). Associations of patient clinical characteristics with overall survival (OS), progression-free interval (PFI), and disease-specific survival (DSS) were assessed by univariate and multivariate analysis using the Cox proportional hazard model. Immune cell infiltration analysis and gene set enrichment analysis (GSEA) were applied to determine any significant effects of LINC00958. High LINC00958 expression was related to early pT stage (P < 0.01), primary therapy outcome (P < 0.01), HPV status (P < 0.001), lymphovascular invasion (P < 0.001), and perineural invasion (P < 0.01). The receiver operating characteristic curve showed strong prognostic power for LINC00958 (area under curve = 0.886). High LINC00958 expression predicted poor OS (P = 0.007), DSS (P = 0.036), and PFI (P = 0.040). LINC00958 was related to signalling pathways and the infiltration of certain immune cells. miR-27b-5p was significantly associated with LINC00958, and downstream NT5E predicted poor survival in HNSCC cases. LINC00958 may affect the prognosis by regulating NT5E via miR-27b-5p, and could serve as a possible factor to predict the prognosis of HNSCC, especially oral squamous cell carcinoma.

Correlation of serum DKK1 level with skeletal phenotype in children with osteogenesis imperfecta

PURPOSE

We aim to detect serum DKK1 level of pediatric patients with OI and to analyze its relationship with the genotype and phenotype of OI patients.

METHODS

A cohort of pediatric OI patients and age-matched healthy children were enrolled. Serum levels of DKK1 and bone turnover biomarkers were measured by enzyme-linked immunosorbent assay. Bone mineral density (BMD) was measured by Dual-energy X-ray absorptiometry. Pathogenic mutations of OI were detected by next-generation sequencing and confirmed by Sanger sequencing.

RESULTS

A total of 62 OI children with mean age of 9.50 (4.86, 12.00) years and 29 healthy children were included in this study. The serum DKK1 concentration in OI children was significantly higher than that in healthy children [5.20 (4.54, 6.32) and 4.08 (3.59, 4.92) ng/mL, P < 0.001]. The serum DKK1 concentration in OI children was negatively correlated with height (r = - 0.282), height Z score (r = - 0.292), ALP concentration (r = - 0.304), lumbar BMD (r = - 0.276), BMD Z score of the lumbar spine and femoral neck (r = - 0.32; r = - 0.27) (all P < 0.05). No significant difference in serum DKK1 concentration was found between OI patients with and without vertebral compression fractures. In patients with spinal deformity (22/62), serum DKK1 concentration was positively correlated with SDI (r = 0.480, P < 0.05). No significant correlation was observed between serum DKK1 concentration and the annual incidence of peripheral fractures, genotype and types of collagen changes in OI children.

CONCLUSION

The serum DKK1 level was not only significantly elevated in OI children, but also closely correlated to their skeletal phenotype, suggesting that DKK1 may become a new biomarker and a potential therapeutic target of OI.

The Relationship between the Level of Coagulative Function Hypertensive Disorder Complicating Pregnancy

BACKGROUND AND AIM

Preeclampsia, a pregnancy complication associated with significant maternal and perinatal mortality and morbidity, has been found to be closely linked to dysfunction in the blood coagulation-fibrinolysis system. However, the relationship between hematologic data and severity and onset time of preeclampsia remains unclear. This study aimed to identify specific hematologic parameters in both preeclamptic and normotensive pregnant women and determine their potential significance in the pathogenesis of preeclampsia.

MATERIALS AND METHODS

A total of 112 patients with gestational hypertension disease were divided into two groups: early-onset preeclampsia (32 cases) and late-onset preeclampsia (80 cases). A control group of 82 normotensive pregnant women matched for age and parity was also selected. Blood samples were collected from all participants to test for specific hematologic parameters.

RESULTS

Mild and severe preeclampsia were associated with lower hemoglobin level (P = 0.01 and P = 0.03, respectively), higher mean platelet volume (P = 0.01 and P = 0.01, respectively) and fibrinogen (P = 0.01 and P = 0.01, respectively), and shorter prothrombin time (P = 0.02 and P = 0.01, respectively) and activated partial thromboplastin time (P = 0.01 and P = 0.02, respectively).

CONCLUSION

These findings have provided evidence on the hematologic coagulative actors in the pathogenesis and severity of preeclampsia.

Unicystic ameloblastoma: A retrospective study on recurrent factors from a single institute database

OBJECTIVE

Unicystic ameloblastomas are a variant of ameloblastoma with a definite recurrence rate because of the biological behaviours of the tumour. The risk factors associated with disease recurrence were analysed in this retrospective study.

METHODS

A total of 132 patients with primary unicystic ameloblastoma reported in a tertiary hospital from 2005 to 2015 were analysed to identify the clinic-pathological and radiological factors associated with recurrence using univariate and multivariate Cox regression analyses.

RESULTS

The mean volume was 30.54cm3 ± 12.55 cm3, and this value differed significantly according to recurrence (p < 0.001). Root resorption and bone cortex/soft tissue invasion were also significantly associated with recurrence among unicystic ameloblastoma patients (p = 0.017 vs. p < 0.001, respectively). A new stage classification system was developed to predict disease recurrence of patients. The multivariate Cox regression analysis revealed that the new stage classification system was the only predictor of disease recurrence in unicystic ameloblastoma patients (p < 0.001), regardless of root resorption, position and site characteristics.

CONCLUSIONS

Volume, root resorption and bone cortex/soft tissue invasion were risk factors for disease recurrence among unicystic ameloblastoma patients. The new stage classification was an independent predictor of disease recurrence in patients with unicystic ameloblastoma.

Disrupted sleep-wake regulation in the MCI-Park mouse model of Parkinson's disease

Disrupted sleep has a profound adverse impact on lives of Parkinson's disease (PD) patients and their caregivers. Sleep disturbances are exceedingly common in PD, with substantial heterogeneity in type, timing, and severity. Among the most common sleep-related symptoms reported by PD patients are insomnia, excessive daytime sleepiness, and sleep fragmentation, characterized by interruptions and decreased continuity of sleep. Alterations in brain wave activity, as measured on the electroencephalogram (EEG), also occur in PD, with changes in the pattern and relative contributions of different frequency bands of the EEG spectrum to overall EEG activity in different vigilance states consistently observed. The mechanisms underlying these PD-associated sleep-wake abnormalities are poorly understood, and they are ineffectively treated by conventional PD therapies. To help fill this gap in knowledge, a new progressive model of PD - the MCI-Park mouse - was studied. Near the transition to the parkinsonian state, these mice exhibited significantly altered sleep-wake regulation, including increased wakefulness, decreased non-rapid eye movement (NREM) sleep, increased sleep fragmentation, reduced rapid eye movement (REM) sleep, and altered EEG activity patterns. These sleep-wake abnormalities resemble those identified in PD patients. Thus, this model may help elucidate the circuit mechanisms underlying sleep disruption in PD and identify targets for novel therapeutic approaches.

Hypoxia macrophage-derived exosomal miR-26b-5p targeting PTEN promotes the development of keloids

Background

Hypoxia is the typical characteristic of keloids. The development of keloids is closely related to the abnormal phenotypic transition of macrophages. However, the role of exosomal microRNAs (miRNAs) derived from hypoxic macrophages in keloids remains unclear. This study aimed to explore the role of hypoxic macrophage-derived exosomes (HMDE) in the occurrence and development of keloids and identify the critical miRNA.

Methods

The expression of CD206+ M2 macrophage in keloids and normal skin tissues was examined through immunofluorescence. The polarization of macrophages under a hypoxia environment was detected through flow cytometry. The internalization of macrophage-derived exosomes in human keloid fibroblasts (HKFs) was detected using a confocal microscope. miRNA sequencing was used to explore the differentially expressed miRNAs in exosomes derived from the normoxic and hypoxic macrophage. Subsequently, the dual-luciferase reporter assay verified that phosphatase and tension homolog (PTEN) was miR-26b-5p's target. The biological function of macrophage-derived exosomes, miR-26b-5p and PTEN were detected using the CCK-8, wound-healing and Transwell assays. Western blot assay was used to confirm the miR-26b-5p's underlying mechanisms and PTEN-PI3K/AKT pathway.

Results

We demonstrated that M2-type macrophages were enriched in keloids and that hypoxia treatment could polarize macrophages toward M2-type. Compared with normoxic macrophages-derived exosomes (NMDE), HMDE promote the proliferation, migration and invasion of HKFs. A total of 38 differential miRNAs (18 upregulated and 20 downregulated) were found between the NMDE and HMDE. miR-26b-5p was enriched in HMDE, which could be transmitted to HKFs. According to the results of the functional assay, exosomal miR-26b-5p produced by macrophages facilitated HKFs' migration, invasion and proliferation via the PTEN-PI3K/AKT pathway.

Conclusions

The highly expressed miR-26b-5p in HMDE promotes the development of keloids via the PTEN-PI3K/AKT pathway.

Genome-wide identification of U-box gene family and expression analysis in response to saline-alkali stress in foxtail millet (Setaria italica L. Beauv)

E3 ubiquitin ligases are central modifiers of plant signaling pathways that regulate protein function, localization, degradation, and other biological processes by linking ubiquitin to target proteins. E3 ubiquitin ligases include proteins with the U-box domain. However, there has been no report about the foxtail millet (Setaria italica L. Beauv) U-box gene family (SiPUB) to date. To explore the function of SiPUBs, this study performed genome-wide identification of SiPUBs and expression analysis of them in response to saline-alkali stress. A total of 70 SiPUBs were identified, which were unevenly distributed on eight chromosomes. Phylogenetic and conserved motif analysis demonstrated that SiPUBs could be clustered into six subfamilies (I-VI), and most SiPUBs were closely related to the homologues in rice. Twenty-eight types of cis-acting elements were identified in SiPUBs, most of which contained many light-responsive elements and plant hormone-responsive elements. Foxtail millet had 19, 78, 85, 18, and 89 collinear U-box gene pairs with Arabidopsis, rice, sorghum, tomato, and maize, respectively. Tissue specific expression analysis revealed great variations in SiPUB expression among different tissues, and most SiPUBs were relatively highly expressed in roots, indicating that SiPUBs may play important roles in root development or other growth and development processes of foxtail millet. Furthermore, the responses of 15 SiPUBs to saline-alkali stress were detected by qRT-PCR. The results showed that saline-alkali stress led to significantly differential expression of these 15 SiPUBs, and SiPUB20/48/70 may play important roles in the response mechanism against saline-alkali stress. Overall, this study provides important information for further exploration of the biological function of U-box genes.

Genome-wide identification of AAAP gene family and expression analysis in response to saline-alkali stress in foxtail millet (Setaria italica L.)

Amino acid/auxin permease (AAAP) genes encode a large family of protein transporters that play important roles in various aspects of plant growth and development. Here, we performed genome-wide identification of members in the foxtail millet (Setaria italica L.) AAAP family (SiAAAP) and their saline-alkali stress-induced expression patterns, resulting in the identification of 65 SiAAAP genes, which could be divided into eight subfamilies. Except for SiAAAP65, the remaining 64 genes were located on nine chromosomes of foxtail millet. Gene structure and conserved motif analyses indicated that the members in the same subfamily are highly conserved. Gene duplication event analysis suggested that tandem duplication may be the main factor driving the expansion of this gene family, and Ka/Ks analysis indicated that all the duplicated genes have undergone purifying selection. Transcriptome analysis showed differential expression of SiAAAPs in roots, stems, leaves, and tassel inflorescence. Analysis of cis-acting elements in the promoter indicated that SiAAAPs contain stress-responsive cis-acting elements. Under saline-alkali stress, qRT-PCR analysis showed that SiAAP3, SiLHT2, and SiAAP16 were differentially expressed between salt-alkali tolerant millet variety JK3 and salt-alkali sensitive millet variety B175. These results suggest that these genes may be involved in or regulate the response to saline-alkali stress, providing a theoretical basis for further studying the function of SiAAAPs.

[Identification and expression analysis of TCP family members in tobacco (Nicotiana tabacum L.)]

TCP family as plant specific transcription factor, plays an important role in different aspects of plant development. In order to screen TCP family members in tobacco, the homologous sequences of tobacco and Arabidopsis TCP family were identified by genome-wide homologous alignment. The physicochemical properties, phylogenetic relationships and cis-acting elements were analyzed by bioinformatics. The homologous genes of AtTCP3/AtTCP4 were screened, and RT-qPCR was used to detect the changes of gene expression upon 20% PEG6000 treatment. The results show that tobacco contains 63 TCP family members. Their amino acid sequence length ranged from 89 aa to 596 aa, and their protein hydropathicity grand average of hydropathicity (GRAVY) ranged from -1.147 to 0.125. The isoelectric point (pI) ranges from 4.42 to 9.94, the number of introns is 0 to 3, and the subcellular location is all located in the nucleus. The results of conserved domain and phylogenetic relationship analysis showed that the tobacco TCP family can be divided into PCF, CIN and CYC/TB1 subfamilies, and each subfamily has a stable sequence. The results of cis-acting elements in gene promoter region showed that TCP family genes contain low docile acting elements (LTR) and a variety of stress and metabolic regulation related elements (MYB, MYC). Analysis of gene expression patterns showed that AtTCP3/AtTCP4 homologous genes (NtTCP6, NtTCP28, NtTCP30, NtTCP33, NtTCP42, NtTCP57, NtTCP63) accounted for 20% PEG6000 treatment significantly up-regulated/down-regulated expression, and NtTCP30 and NtTCP57 genes were selected as candidate genes in response to drought. The results of this study analyzed the TCP family in the tobacco genome and provided candidate genes for the study of drought-resistance gene function and variety breeding in tobacco.

Genotype-phenotype relationship and comparison between eastern and western patients with osteogenesis imperfecta

PURPOSE

To evaluate the genotypic and phenotypic relationship in a large cohort of OI patients and to compare the differences between eastern and western OI cohorts.

METHODS

A total of 671 OI patients were included. Pathogenic mutations were identified, phenotypic information was collected, and relationships between genotypes and phenotypes were analyzed. Literature about western OI cohorts was searched, and differences were compared between eastern and western OI cohorts.

RESULTS

A total of 560 OI patients were identified as carrying OI pathogenic mutations, and the positive detection rate of disease-causing gene mutations was 83.5%. Mutations in 15 OI candidate genes were identified, with COL1A1 (n = 308, 55%) and COL1A2 (n = 164, 29%) being the most common mutations, and SERPINF1 and WNT1 being the most common biallelic variants. Of the 414 probands, 48.8, 16.9, 29.2 and 5.1% had OI types I, III, IV and V, respectively. Peripheral fracture was the most common phenotype (96.6%), and femurs (34.7%) were most commonly affected. Vertebral compression fracture was observed in 43.5% of OI patients. Biallelic or COL1A2 mutation led to more bone deformities and poorer mobility than COL1A1 mutation (all P < 0.05). Glycine substitution of COL1A1 or COL1A2 or biallelic variants led to more severe phenotypes than haploinsufficiency of collagen type I α chains, which induced the mildest phenotypes. Although the gene mutation spectrum varied among countries, the fracture incidence was similar between eastern and western OI cohorts.

CONCLUSION

The findings are valuable for accurate diagnosis and treatment of OI, mechanism exploration and prognosis judgment. Genetic profiles of OI may vary among races, but the mechanism needs to be explored.

Disturbed white matter integrity on diffusion tensor imaging in young children with epilepsy

AIM

To evaluate whether abnormalities in white matter (WM) integrity are present in young children with epilepsy.

MATERIALS AND METHODS

Twelve children (3-6 years old) with epilepsy and six matched healthy controls were recruited for brain diffusion tensor imaging (DTI). Track-based spatial statistics (TBSS) was used to analyse and compare DTI indices of mean diffusivity (MD), fractional anisotropy (FA), axial and radial diffusivity (AD/RD) between patients and controls, and correlations between clinical variables and DTI parameters were analysed.

RESULTS

Compared with controls, patients showed increased FA in the left superior corona radiata and increased AD in the bilateral superior corona radiata. In children with generalised epilepsy, FA was increased in the left external capsule, while AD was decreased in the body of the corpus callosum, the left external capsule and the left superior longitudinal fasciculus. In those with focal epilepsy, FA was increased in the genu and body of the corpus callosum, and RD was decreased in the genu of the corpus callosum and left external capsule. Compared with partial epilepsy, generalised epilepsy was associated with increased FA in the right anterior corona radiata and decreased RD in the right anterior corona radiata and the genu and body of the corpus callosum. No significant correlations were observed between clinical variables and DTI parameters.

CONCLUSIONS

The results of this study indicate that the microstructure of the white matter is disturbed by epileptic discharges and a compensatory response occurs during early brain development.

CXC ligand 13 orchestrates an immunoactive microenvironment and enhances immunotherapy response in head and neck squamous cell carcinoma

Objectives: This study aims to systematically explore the role of chemokine CXC ligand 13 (CXCL13) in head and neck squamous cell carcinoma (HNSCC). Methods: The Genotype-Tissue Expression (GTEx) and The Cancer Genome Atlas (TCGA) databases provided the RNA-seq data for cancer and normal tissues, respectively. Gene set enrichment analysis was applied to search the cancer hallmarks associated with CXCL13 expression. TIMER2.0 was the main platform used to investigate the immune cell infiltration related to CXCL13. Immunohistochemistry was applied to explore the relationship between CXCL13 and patients' prognosis and the relationship between CXCL13 and tertiary lymphoid structures (TLSs). Results: The expression of CXCL13 was upregulated in most tumors, including HNSCC. The higher expression of CXCL13 was closely related to the positive prognosis of HNSCC. CXCL13 was mainly expressed in B cells and CD8 + T cells, revealing the relationship between its expression and immune activation in the tumor microenvironment. Furthermore, immunohistochemistry and multiple fluorescence staining analysis of HNSCC samples showed a powerful correlation between CXCL13 expression, TLSs formation, and positive prognosis. Finally, CXCL13 significantly increased the response to cancer immunotherapy. Conclusions: CXCL13 may function as a potential biomarker for predicting prognosis and immunotherapy response and associate with TLSs in HNSCC.

Multi-mode heterodyne laser interferometry realized via software defined radio

The agile generation and control of multiple optical frequency modes combined with the realtime processing of multi-mode data provides access to experimentation in domains such as optomechanical systems, optical information processing, and multi-mode spectroscopy. The latter, specifically spectroscopy of spectral-hole burning (SHB), has motivated our development of a multi-mode heterodyne laser interferometric scheme centered around a software-defined radio platform for signal generation and processing, with development in an entirely open-source environment. A challenge to SHB is the high level of shot noise due to the laser power constraint imposed by the spectroscopic sample. Here, we have demonstrated the production, detection, and separation of multiple optical frequency modes to the benefit of optical environment sensing for realtime phase noise subtraction as well as shot noise reduction through multi-mode averaging. This has allowed us to achieve improved noise performance in low-optical-power interferometry. Although our target application is laser stabilization via SHB in cryogenic temperature rare-earth doped crystals, these techniques may be employed in a variety of different contexts.

Targeting cellular metabolism in head and neck cancer precision medicine era: A promising strategy to overcome therapy resistance

Head and neck squamous cell carcinoma (HNSCC) is among the most prevalent cancer worldwide, with the most severe impact on quality of life of patients. Despite the development of multimodal therapeutic approaches, the clinical outcomes of HNSCC are still unsatisfactory, mainly caused by relatively low responsiveness to treatment and severe drug resistance. Metabolic reprogramming is currently considered to play a pivotal role in anticancer therapeutic resistance. This review aimed to define the specific metabolic programs and adaptations in HNSCC therapy resistance. An extensive literature review of HNSCC was conducted via the PubMed including metabolic reprogramming, chemo- or immune-therapy resistance. Glucose metabolism, fatty acid metabolism, and amino acid metabolism are closely related to the malignant biological characteristics of cancer, anti-tumor drug resistance, and adverse clinical results. For HNSCC, pyruvate, lactate and almost all lipid categories are related to the occurrence and maintenance of drug resistance, and targeting amino acid metabolism can prevent tumor development and enhance the response of drug-resistant tumors to anticancer therapy. This review will provide a better understanding of the altered metabolism in therapy resistance of HNSCC and promote the development of new therapeutic strategies against HNSCC, thereby contribute to a more efficacious precision medicine.

Proteomic analysis of leaves and roots during drought stress and recovery in Setaria italica L

Drought is a major environmental factor that limits agricultural crop productivity and threatens food security. Foxtail millet is a model crop with excellent abiotic stress tolerance and is consequently an important subject for obtaining a better understanding of the molecular mechanisms underlying plant responses to drought and recovery. Here the physiological and proteomic responses of foxtail millet (cultivar Yugu1) leaves and roots to drought treatments and recovery were evaluated. Drought-treated foxtail millet exhibited increased relative electrolyte leakage and decreased relative water content and chlorophyll content compared to control and rewatering plants. A global analysis of protein profiles was evaluated for drought-treated and recovery treatment leaves and roots. We also identified differentially abundant proteins in drought and recovery groups, enabling comparisons between leaf and root tissue responses to the conditions. The principal component analysis suggested a clear distinction between leaf and root proteomes for the drought-treated and recovery treatment plants. Gene Ontology enrichment and co-expression analyses indicated that the biological responses of leaves differed from those in roots after drought and drought recovery. These results provide new insights and data resources to investigate the molecular basis of tissue-specific functional responses of foxtail millet during drought and recovery, thereby significantly informing crop breeding.

Prediction of synchronous distant metastasis of primary pancreatic ductal adenocarcinoma using the radiomics features derived from 18F-FDG PET and MRI

AIM

To explore the potential of the joint radiomics analysis of positron-emission tomography (PET) and magnetic resonance imaging (MRI) of primary tumours for predicting the risk of synchronous distant metastasis (SDM) in patients with pancreatic ductal adenocarcinoma (PDAC).

MATERIALS AND METHODS

18F-FDG PET and MRI images of PDAC patients from January 2011 to December 2020 were collected retrospectively. Patients (n=66) who received 18F-FDG PET/CT and MRI were included in a development group. Patients (n=25) scanned with hybrid PET/MRI were incorporated in an external test group. A radiomics signature was constructed using the least absolute shrinkage and selection operator algorithm to select PET-MRI radiomics features of primary PDAC tumours. A radiomics nomogram was developed by combining the radiomics signature and important clinical indicators using univariate and multivariate analysis to assess patients' metastasis risk. The nomogram was verified with the employment of an external test group.

RESULTS

Regarding the development cohort, the radiomics nomogram was found to be better for predicting the risk of distant metastasis (area under the curve [AUC]: 0.93, sensitivity: 87%, specificity: 85%) than the clinical model (AUC: 0.70, p<0.001; sensitivity:70%, specificity: 65%) and the radiomics signature (AUC: 0.89, p>0.05; sensitivity: 65%, specificity:100%). Concerning the external test cohort, the radiomics nomogram yielded an AUC of 0.85.

CONCLUSION

PET-MRI based radiomics analysis exhibited effective prediction of the risk of SDM for preoperative PDAC patients and may offer complementary information and provide hints for cancer staging.

Potential Predictive Value of Intravoxel Incoherent Motion Magnetic Resonance for Xerostomia of Nasopharyngeal Carcinoma

PURPOSE/OBJECTIVE(S)

Xerostomia, caused by radiation-induced parotid damage, is the most commonly reported complications of radiotherapy (RT) to nasopharyngeal carcinoma (NPC). This study aimed to evaluate the value of IVIM MR in monitoring radiation parotid gland damage and predicting the risk of xerostomia.

MATERIALS/METHODS

A total of 54 patients were enrolled and underwent IVIM MR scans at before RT, after the fifth fraction, halfway through the course of RT, and at the end of radiotherapy. The parameters of IVIM MR include pseudo-diffusion coefficient (D*), perfusion fraction (f), and pure diffusion coefficient (D). The degree of xerostomia in NPC patients was assessed before each MR examination using the acute radiation morbidity scoring criteria proposed by the Radiation Therapy Oncology Group (RTOG). Concurrently, the time when the patient first reported suffering from xerostomia was recorded. The IVIM parameters trend throughout the RT, and the relationships between IVIM parameters and xerostomia, were analyzed.

RESULTS

All of the IVIM parameters increased from pre-RT to post-RT significantly (all p < 0.001). The increase rate of D from pre-RT to halfway through the RT was 32.61%, which was significantly higher than 15.64% from halfway to post-RT (p<0.001), indicating that cell necrosis in the first half of treatment is significantly higher than that in the second half. Both D* and F had significantly increased from pre-RT to halfway through the radiotherapy (p<0.001), with an increase rate of 19.58% and 29.38%, respectively. However, no significant increase was observed from Halfway to post-RT (p>0.05), with an increase rate of 4.10% and 8.30%, respectively. This may be due to radiation-induced vasculitic dilation that is significant in the first half of the radiotherapy but plateaus in the second half. Pre-D (OR = 23.85; 95% CI = 2.39, 237.82; p = .007) and pre-D* (OR = 0.75; 95% CI = 0.63, 0.91; p = 0.003) are independent influencing factors for xerostomia at 3 months after the completion of RT. D and F were significantly higher after the fifth fraction compared with Pre-RT (both p<0.05), respectively increased 31.25% and 25.16%. D* increase by 15% (p = 0.081). IVIM scans can assess parotid gland damage early. And the average time of parotid damage underwent IVIM scan was 5.99 ± 0.84 (day), much earlier than 11.84 ± 2.74 (day) according to RTOG.

CONCLUSION

Our study indicates that IVIM MR can dynamically monitor radiotherapy-induced parotid gland damage, and much earlier and objectively than RTOG.

Fibulin-1 Regulates Initiation of Successional Dental Lamina

In humans, teeth are replaced only once, and the successional dental lamina (SDL) of the permanent tooth is maintained in a quiescent state until adolescence. Recently, we showed that biomechanical stress generated by the rapid growth of the deciduous tooth inhibits SDL development via integrin β1-RUNX2 signaling at embryonic day 60 (E60) in miniature pigs. However, the mechanism by which RUNX2 regulates SDL initiation within the SDL stem cell niche remains unclear. In the current study, we transcriptionally profiled single cells from SDL and surrounding mesenchyme at E60 and identified the landscape of cellular heterogeneity. We then identified a specific fibroblast subtype in the dental follicle mesenchyme between the deciduous tooth and the SDL of the permanent tooth (DFDP), which constitutes the inner part of the niche (deciduous tooth side). Compared with traditional dental follicle cells, the specific expression profile of DFDP was identified and found to be related to biomechanical stress. Subsequently, we found that RUNX2 could bind to the enhancer regions of Fbln1 (gene of fibulin-1), one of the marker genes for DFDP. Through gain- and loss-of-function experiments, we proved that the biomechanical stress-mediated RUNX2-fibulin-1 axis inhibits the initiation of SDL by maintaining SDL niche homeostasis.

Robust Radiosensitization by Combined Treatment of Cancer Cells with Talazoparib and Polθ Inhibitors

PURPOSE/OBJECTIVE(S)

The PARP inhibitor talazoparib is synthetically lethal with HR-defective tumors and functions as a potent radiosensitizer specifically of cancer cells. Talazoparib exerts this unique radiosensitizing property by shifting ionizing radiation (IR)-induced DNA double strand break (DSB) repair towards error-prone alternative end-joining (alt-EJ). DNA polymerase theta (Polθ, encoded by POLQ) is a key component of alt-EJ. Here, we tested the hypothesis that inhibition of alt-EJ with Polθ ablation or using specific small molecule inhibitors can further increase talazoparib-induced radiosensitization.

MATERIALS/METHODS

U2OS, A549, and their corresponding POLQ ablated/mutant cell lines were treated with talazoparib and/or Polθ inhibitors ART558/novobiocin prior to irradiation. siRNAs against CtIP, MRE11, EXO1; and a specific inhibitor of DNA2 were employed to suppress DNA end resection. Radiosensitization was assessed by clonogenic survival. Olaparib, rucaparib, and veliparib were also tested under similar conditions. DSB repair and end resection were measured by scoring γH2AX and RPA nuclear foci, respectively. Chromosomal abnormalities were assessed using G2-specific cytogenetics analysis.

RESULTS

Genetic ablation or pharmacological inhibition of Polθ robustly enhanced talazoparib mediated radiosensitization by ∼40-70%. Notably, Polθ inhibition had a much lower effect (by ∼7-17%) when combined with other clinically used PARP inhibitors, olaparib, rucaparib, and veliparib. Polθ inhibition significantly suppressed talazoparib-induced translocation formation in irradiated cells. In addition, combined treatment with Polθ inhibitor and talazoparib attenuated DSB repair, resulting in ∼60% unresolved γH2AX foci and ∼40% unresolved chromatid breaks at 5h post IR. Talazoparib promoted resection of DNA ends as demonstrated by an increase in RPA foci. The resection process requires the activities of CtIP and MRE11, but not of DNA2 or EXO1. Finally, CtIP and MRE11 knockdown impaired radiosensitization following a combined talazoparib/Polθ inhibition treatment.

CONCLUSION

Talazoparib increases the reliance of irradiated cancer cells on Polθ-mediated alt-EJ owing to the increased CtIP/MRE11-dependent resection it produces. Combining talazoparib with Polθ inhibitors has therefore great potential in improving radiotherapy of human tumors.

Effect of MTA3 Inhibition of Glutamine Synthetase-Mediated Glutaminolysis on Radiosensitivity of Patients with Esophageal Cancer

PURPOSE/OBJECTIVE(S)

Metastasis-associated protein 3 (MTA3) can serve as a tumor suppressor in many cancer types. However, the role of MTA3 in radiosensitivity of patients with esophageal squamous cell cancer (ESCC) remains unclear. We thus investigated the function of MTA3 in radiosensitivity for ESCC, one of the most common digestive cancers.

MATERIALS/METHODS

The colony formation assay and nude mice xenograft tumor assay were performed to investigate the effect of MTA3 on radiosensitivity in ESCC. Glutamine consumption assay kit and glutamate production assay kit were used to assess the glutaminolysis. Glutaminase (GLS) Activity Assay Kit and Glutamine Synthetase (GS) Activity Assay Kit were used to analyze the activity of specific metabolic enzymes dominate glutaminolysis. The regulatory mechanism of glutaminolysis by MTA3 was confirmed using Chromatin immunoprecipitation assay and Gaussia luciferase assay. The expression levels of MTA3 and GS in ESCC primary tissues were evaluated using immunohistochemistry. Survival curves were plotted with the Kaplan-Meier method and compared by log-rank test.

RESULTS

The colony formation assay showed that MTA3 depletion and overexpression caused significantly higher and lower clonogenic survival after different doses of irradiation (IR), respectively. When these cells were subcutaneously injected into nude mice, the tumors derived from the cells with MTA3 overexpression and MTA3 knockdown were significantly smaller and bigger after IR, respectively. These findings suggest that MTA3 can enhance radiosensitivity in vitro and in vivo. Meanwhile, overexpressed and knockdown MTA3 can repress and expedite glutamine consumption and glutamate production uniformly, respectively. To determine how MTA3 acts on glutaminolysis, the activity of two specific metabolic enzymes dominate this metabolism, GS and GLS, were evaluated. It found that overexpressed and knockdown MTA3 can restrain and enhance the activity of GS, respectively, but have less effect on GLS. Moreover, the decreased radiosensitivity mediated by MTA3 knockdown is significantly increased when treated with GS inhibitor, suggesting that GS plays a crucial role in MTA3-mediated radiosensitivity enhancement. Mechanistically, Chromatin immunoprecipitation assay and Gaussia luciferase assay showed that MTA3 was recruited to the promoter of GS and suppressed GS transcription. However, knockdown of GATA3 abolished MTA3's repressive effect on GS and inhibited the MTA3's occupation on the promoter region of GS. These results collectively demonstrated that, in ESCC cells, MTA3 is recruited by GATA3 to inhibit GS expression, then ultimately represses glutaminolysis and enhances radiosensitivity. Finally, we showed that the ESCC patients in the MTA3low/GShigh group is significantly associated with shorter overall survival.

CONCLUSION

MTA3 is capable of enhancing radiosensitivity through downregulating GS and MTA3low/GShigh might be a potential prognostic factor for ESCC patients.

[Progress in the application of alveolar organoids in common lung diseases]

Organoids are tissue cultures formed by culturing cells in three-dimensional environments that simulate the physiological or pathological conditions of the human body. The cultivation of organoids is used to study the temporal and spatial transformation of cells during the development of tissues or organs, to investigate changes in cellular functions and inter-communications caused by various risk factors, and to discover potential therapeutic targets. This article provided an overview of the cultivation and identification methods of alveolar organoids, as well as the research progress in their application to common respiratory diseases such as pulmonary fibrosis, chronic obstructive pulmonary disease, viral pneumonia, and so on. The limitations and future applications of alveolar organoids are also analyzed and discussed.

Van der Waals isotope heterostructures for engineering phonon polariton dispersions

Element isotopes are characterized by distinct atomic masses and nuclear spins, which can significantly influence material properties. Notably, however, isotopes in natural materials are homogenously distributed in space. Here, we propose a method to configure material properties by repositioning isotopes in engineered van der Waals (vdW) isotopic heterostructures. We showcase the properties of hexagonal boron nitride (hBN) isotopic heterostructures in engineering confined photon-lattice waves-hyperbolic phonon polaritons. By varying the composition, stacking order, and thicknesses of h10BN and h11BN building blocks, hyperbolic phonon polaritons can be engineered into a variety of energy-momentum dispersions. These confined and tailored polaritons are promising for various nanophotonic and thermal functionalities. Due to the universality and importance of isotopes, our vdW isotope heterostructuring method can be applied to engineer the properties of a broad range of materials.