PD-1/CD80+ small extracellular vesicles from immunocytes induce cold tumours featured with enhanced adaptive immunosuppression.

Only a minority of cancer patients benefit from immune checkpoint blockade therapy. Sophisticated cross-talk among different immune checkpoint pathways as well as interaction pattern of immune checkpoint molecules carried on circulating small extracellular vesicles (sEV) might contribute to the low response rate. Here we demonstrate that PD-1 and CD80 carried on immunocyte-derived sEVs (I-sEV) induce an adaptive redistribution of PD-L1 in tumour cells. The resulting decreased cell membrane PD-L1 expression and increased sEV PD-L1 secretion into the circulation contribute to systemic immunosuppression. PD-1/CD80+ I-sEVs also induce downregulation of adhesion- and antigen presentation-related molecules on tumour cells and impaired immune cell infiltration, thereby converting tumours to an immunologically cold phenotype. Moreover, synchronous analysis of multiple checkpoint molecules, including PD-1, CD80 and PD-L1, on circulating sEVs distinguishes clinical responders from those patients who poorly respond to anti-PD-1 treatment. Altogether, our study shows that sEVs carry multiple inhibitory immune checkpoints proteins, which form a potentially targetable adaptive loop to suppress antitumour immunity.

A tumor cell exosome-mimicking multifunctional nanozyme for targeted breast cancer radiotherapy.

Radiotherapy (RT) has been extensively used for the treatment of breast cancer. However, the efficacy of RT is reduced by the high content of reducing species within cells (such as glutathione (GSH)). In addition, high-dose radiotherapy is often accompanied by serious side effects. In an attempt to resolve these issues, a tumor cell exosome-mimicking multifunctional nanozyme system (CuPy-Au@EM) was developed as a radiosensitizer, which consists of an internal AuNP-embedded CuPy nanozyme core and an external tumor cell exosome membrane. The exosome membrane protein on the surface of CuPy-Au@EM leads to the accurate localization of nano-materials in the tumor site; simultaneously, the level of H2O2 will be enhanced because of the GOx-like activity of AuNPs. Then CuPy-Au@EM would continue to trigger a rapid decline in cellular GSH content and the production of a large number of hydroxyl radicals (˙OH) through its glutathione peroxidase (GPx) and peroxidase (POD) activities allows for the extension of the radiotherapeutic cascade. Studies conducted in vivo and in vitro demonstrated that the combination of CuPy-Au@EM and moderate dose RT (4 Gy) can significantly reduce tumor proliferation. These findings indicated that CuPy-Au@EM nanospheres could be plausibly developed into promising radio-sensitizers on tumors.

HRS Regulates Small Extracellular Vesicle PD-L1 Secretion and Is Associated with Anti-PD-1 Treatment Efficacy.

PD-L1 localized to immunosuppressive small extracellular vesicles (sEV PD-L1) contributes to tumor progression and is associated with resistance to immune-checkpoint blockade (ICB) therapy. Here, by establishing a screening strategy with a combination of tissue microarray (TMA), IHC staining, and measurement of circulating sEV PD-L1, we found that the endosomal sorting complex required for transport (ESCRT) member protein hepatocyte growth factor-regulated tyrosine kinase substrate (HRS) was the key regulator of circulating sEV PD-L1 in head and neck squamous cell carcinoma (HNSCC) patients. Increased HRS expression was found in tumor tissues and positively correlated with elevated circulating sEV PD-L1 in patients with HNSCC. The expression of HRS was also negatively correlated to the infiltration of CD8+ T cells. Knockdown of HRS markedly reduced PD-L1 expression in HNSCC cell-derived sEVs, and these sEVs from HRS knockdown cells showed decreased immunosuppressive effects on CD8+ T cells. Knockout of HRS inhibited tumor growth in immunocompetent mice together with PD-1 blockade. Moreover, a higher HRS expression was associated with a lower response rate to anti-PD-1 therapy in patients with HNSCC. In summary, our study reveals HRS, the core component of ESCRT-0, regulates sEV PD-L1 secretion, and is associated with the response to ICB therapy in patients with HNSCC, suggesting HRS is a promising target to improve cancer immunotherapy.

Favorable QTLs from Oryza longistaminata improve rice drought resistance.

BACKGROUND: Drought is the major abiotic stress to rice grain production under unpredictable changing climatic environments. Wild rice of O. longistaminata show diverse responses and strong tolerance to stress environments. In order to identify whether the O. longistaminata can improve the rice drought resistance or not, a BIL population of 143 BC2F20 lines derived from the cross between the cultivar rice 9311 and O. longistaminata were assessed under stress of 20% PEG6000. RESULTS: In total, 28 QTLs related to drought resistance based on eight agronomic traits of seedlings were identified. Of which, thirteen QTLs including two QTLs for leaf drying, one QTL for leaf rolling, one QTL for leaf number, five QTLs for dry weight of root, two QTLs for dry weight of shoot, one QTL for maximum root length and two QTLs for maximum shoot length were derived from O. longistaminata. What's more, qDWR8.1 for dry weight of root was repeatedly detected and fine-mapped to an interval about 36.2 Kb. The unique allele of MH08g0242800 annotated as ATP-dependent Clp protease proteolytic subunit from O. longistaminata was suggested as the candidate gene for drought resistance. Further, six representative BIL lines were stably characterized showing significantly stronger drought resistance than 9311 based on principle component analysis, they each contained 2 ~ 5 QTLs including qDWR8.1 from O. longistaminata. CONCLUSIONS: Together, our results indicate that the QTLs from O. longistaminata can effectively enhance the drought tolerance of rice, showing great potential value in breeding of elite rice varieties, which will lay a novel insight into the genetic network for drought tolerance of rice.

Creation of Elite Rice with High-Yield, Superior-Quality and High Resistance to Brown Planthopper Based on Molecular Design.

Breeding rice (Oryza sativa L.) with high yield, superior quality, desired grain shape and high resistance is the goal of breeding to meet the needs of current consumers. It is usually hard to combine multiple complex traits based on traditional breeding methods because they are frequently antagonistic to each other. However, molecular design breeding, as a novel breeding method, is an optional alternative to this challenge. To demonstrate molecular design breeding, 15 favorable genes from five parent lines were pyramided together to develop elite rice with high-yield, superior-quality, desired grain shape and high resistance to brown planthopper (BPH). The parental lines were 9311, the recurrent parent, carrying APO1, Ghd7, Ghd8 and Gn1a for high yield, GS3 and qSW5 for grain shape, and Wx and ALK for eating and cooking quality; 1880 with Gn8.1 for large panicles; Luo-Yu-Xiang carrying GW7 for grain shape and SBE3, SSIV2 and SSIII for eating and cooking quality; Luoyang6 with Bph6 and Luoyang9 with Bph9 for BPH resistance. After careful screening for the 15 targeted genes, desired phenotype and maximum genetic background from 9311, three molecular design lines with desired phenotypes, named as MD1 (Molecular design 1), MD2 and MD3 were developed. MD3 carried all 15 targeted genes, and MD1 and MD2 had 14 of the 15 targeted genes. Only SBE3 was not introgressed into MD1 and MD2 but this had minimal impact on the gel consistency and alkali spreading value. These newly bred lines exhibited higher yield potential, better grain quality with slender grains, low amylose content, high gel consistency and alkali spreading value, and higher BPH resistance compared to the parent 9311. In this study, we successfully created three novel rice lines with high yield, superior quality and improved BPH resistance by rational molecular design. Our results demonstrate molecular design is a powerful strategy to improve multiple complex traits and will provide a reference for the future commercial rice improvement.

Quantitative Trait Locus Mapping of Salt Tolerance in Wild Rice Oryza longistaminata.

Salt stress is one of the most severe adverse environments in rice production; increasing salinization is seriously endangering rice production around the world. In this study, a rice backcross inbred line (BIL) population derived from the cross of 9311 and wild rice Oryza longistaminata was employed to identify the favorable genetic loci of O. longistaminata for salt tolerance. A total of 27 quantitative trait loci (QTLs) related to salt tolerance were identified in 140 rice BILs, and 17 QTLs formed seven QTL clusters on different chromosomes, of which 18 QTLs were derived from O. longistaminata, and a QTL for salt injury score (SIS), water content of seedlings (WCS) under salt treatment, and relative water content of seedlings (RWCS) was repeatedly detected and colocalized at the same site on chromosome 2, and a cytochrome P450 86B1 (MH02t0466900) was suggested as the potential candidate gene responsible for the salt tolerance based on sequence and expression analysis. These findings laid the foundation for further improving rice salt tolerance through molecular breeding in the future.

Oral pH value predicts the incidence of radiotherapy related caries in nasopharyngeal carcinoma patients.

Radiotherapy-related caries is a complication of radiotherapy for nasopharyngeal carcinoma; however, factors influencing the occurrence, accurate prediction of onset, and protective factors of radiotherapy-related caries remain unclear. This study analyzed risk factors, disease predictors, and protective factors for radiotherapy-related caries in nasopharyngeal carcinoma. This prospective study included 138 nasopharyngeal carcinoma patients receiving radical radiotherapy at our hospital during June 2012-December 2016 and were followed up for dental caries. Patients' clinical data on radiotherapy were collected, dynamic monitoring was performed to assess changes in oral pH values, and a questionnaire survey was administered to collect patients' lifestyle habits. Time-dependent cox regression trees, event-free Kaplan-Meier curve, Mann-Whitely U test were used to analysis the results. The median follow-up time was 30 (12-60) months. Radiotherapy-related caries occurred in 28 cases (20.3%). Univariate analyses showed that radiotherapy-related caries was associated with patient's age, oral saliva pH value, green tea consumption, and radiation dose to sublingual glands, but not with the radiation dose to the parotid and submandibular glands. Multivariate analysis showed that oral saliva pH value [hazard ratio (HR) = 0.390, 95% confidence interval = 0.204-0.746] was an independent prognostic factor for radiotherapy-related caries. Patients with oral saliva pH values ≤ 5.3 in the 9th month after radiotherapy represented a significantly higher risks for radiotherapy-related caries (p < 0.001). Green tea consumption was associated with the occurrence of radiotherapy-related caries, and oral saliva pH values could predict the occurrence of radiotherapy-related caries. Limiting radiation doses to sublingual glands can reduce the occurrence of radiotherapy-related caries.

Overexpressed pseudogene MT1L associated with tumor immune infiltrates and indicates a worse prognosis in BLCA.

BACKGROUND: BLCA is a common cancer worldwide, and it is both aggressive and fatal. Immunotherapy (ICT) has achieved an excellent curative effect in BLCA; however, only some BLCA patients can benefit from ICT. MT1L is a pseudogene, and a previous study suggested that MT1L can be used as an indicator of prognosis in colorectal cancer. However, the role of MT1L in BLCA has not yet been determined. METHODS: Data were collected from TCGA, and logistic regression, Kaplan-Meier plotter, and multivariate Cox analysis were performed to demonstrate the correlation between the pseudogene MT1L and the prognosis of BLCA. To identify the association of MT1L with tumor-infiltrating immune cells, TIMER and TISIDB were utilized. Additionally, GSEA was performed to elucidate the potential biological function. RESULTS: The expression of MT1L was decreased in BLCA. Additionally, MT1L was positively correlated with immune cells, such as Tregs (ρ = 0.708) and MDSCs (ρ = 0.664). We also confirmed that MT1L is related to typical markers of immune cells, such as PD-1 and CTLA-4. In addition, a high MT1L expression level was associated with the advanced T and N and high grade in BLCA. Increased expression of MT1L was significantly associated with shorter OS times of BLCA patients (p < 0.05). Multivariate Cox analysis revealed that MT1L expression could be an independent prognostic factor in BLCA. CONCLUSION: Collectively, our findings demonstrated that the pseudogene MT1L regulates the immune microenvironment, correlates with poor survival, and is an independent prognostic biomarker in BLCA.

Pretreatment serum vitamin level predicts severity of radiation-induced oral mucositis in patients with nasopharyngeal carcinoma.

BACKGROUND: Radiation-induced mucositis (RIOM) is a common radiotherapy toxicity. We aimed to evaluate the relationship of serum vitamin status with RIOM among nasopharyngeal carcinoma (NPC) patients who underwent radiotherapy. METHODS: NPC patients who underwent concurrent chemoradiotherapy with available pretreatment serum vitamin values were included. Serum vitamin levels and clinical characteristics were collected. Logistic regression analysis and receiver operating characteristic curves were conducted to explore the potential risk factors and corresponding cut-off values for severe RIOM. RESULTS: Two hundred and forty NPC patients were enrolled. Multivariate regression analysis showed that mean oral cavity radiation dose (OR = 2.042; 95% CI = 1.585-2.630; P < .001), weekly concurrent chemotherapy (OR = 3.898; 95% CI = 1.085-14.004; P = .037), lower serum level of vitamin B2 (OR = 0.951; 95% CI = 0.924-0.978; P < .001), and vitamin C (OR = 0.455; 95% CI = 0.346-0.598; P < .001) were independent risk factors for developing severe RIOM. CONCLUSIONS: The findings of this study revealed that serum vitamin status could predict the severity of RIOM, providing a theoretical basis for the prevention and treatment of RIOM.

Impact of treatment delay due to the pandemic of COVID-19 on the efficacy of immunotherapy in head and neck cancer patients.

Immunotherapy has been a new standard for recurrent/metastatic head and neck cancers (R/M HNC). One of the prominent characteristics of cancer immunotherapy is the induction of immune memory followed by endured treatment response. However, whether and how a treatment delay would impact on the efficacy of immunotherapy has not been well determined. During the outbreak of COVID-19, a number of cancer patients in Wuhan, the epicenter of the pandemic in China, had experienced long-lasting city lockdown and delay of immunotherapies. Here, we retrospectively analyzed 24 HNC patients treated with immune checkpoint inhibitors in our cancer institute prior to the outbreak of COVID-19 who were re-evaluated after the restoration of regular medical care. Of these 24 patients, 10 patients had achieved complete response (CR) or partial response (PR), 12 patients had achieved stable disease (SD), and 2 patients had received just one cycle treatment without efficacy evaluation before treatment delay. The median delay was 3.75 months (range 1.73-8.17 months). Re-evaluation after treatment delay revealed that ten patients (10/10) who achieved CR or PR, two patients (2/2) who received just one cycle treatment without efficacy evaluation and seven patients (7/12) who achieved SD before outbreak of COVID-19 maintained tumor response after treatment delay. Among the rest five patients who had achieved SD, four patients were re-evaluated as progressive disease (PD) due to treatment delay and one patient died after treatment interruption without re-evaluation. Our results from a small cohort of R/M HNC patients showed that treatment delay of three to four months might have mild, if any, impact on the efficacy of immunotherapy for patients with controlled disease.

Outcomes of novel coronavirus disease 2019 (COVID-19) infection in 107 patients with cancer from Wuhan, China.

BACKGROUND: Patients with cancer have a higher risk of coronavirus disease 2019 (COVID-19) than noncancer patients. The authors conducted a multicenter retrospective study to investigate the clinical manifestations and outcomes of patients with cancer who are diagnosed with COVID-19. METHODS: The authors reviewed the medical records of hospitalized patients who were treated at 5 hospitals in Wuhan City, China, between January 5 and March 18, 2020. Clinical parameters relating to cancer history (type and treatment) and COVID-19 were collected. The primary outcome was overall survival (OS). Secondary analyses were the association between clinical factors and severe COVID-19 and OS. RESULTS: A total of 107 patients with cancer were diagnosed with COVID-19, with a median age of 66 years (range, 37-98 years). Lung (21 patients; 19.6%), gastrointestinal (20 patients; 18.7%), and genitourinary (20 patients; 18.7%) cancers were the most common cancer diagnoses. A total of 37 patients (34.6%) were receiving active anticancer treatment when diagnosed with COVID-19, whereas 70 patients (65.4%) were on follow-up. Overall, 52.3% of patients (56 patients) developed severe COVID-19; this rate was found to be higher among patients receiving anticancer treatment than those on follow-up (64.9% vs 45.7%), which corresponded to an inferior OS in the former subgroup of patients (hazard ratio, 3.365; 95% CI, 1.455-7.782 [P = .005]). The detrimental effect of anticancer treatment on OS was found to be independent of exposure to systemic therapy (case fatality rate of 33.3% [systemic therapy] vs 43.8% [nonsystemic therapy]). CONCLUSIONS: The results of the current study demonstrated that >50.0% of infected patients with cancer are susceptible to severe COVID-19. This risk is aggravated by simultaneous anticancer treatment and portends for a worse survival, despite treatment for COVID-19.

Association between oral contraceptive use as a risk factor and triple-negative breast cancer: A systematic review and meta-analysis.

Triple-negative breast cancer (TNBC), a unique subtype of breast cancer, which is resistant to endocrine and targeted therapy, usually relapses early, progresses rapidly and is associated with a poor prognosis. Epidemiological investigations focusing on the association between risk factors and the onset of TNBC demonstrated that the incidence of TNBC exhibits a significant correlation with anthropometric, geographical and demographic parameters. The aim of the present systematic review and meta-analysis was to evaluate the strength of the association between the use of oral contraceptives (OCs) and TNBC. Two databases (PubMed Central/PubMed, Web of Science) and secondary references were searched to identify studies meeting the priorly established inclusion criteria. Case-control studies published between January, 2005 and March, 2016 were searched using the key words (triple-negative breast cancer OR basal-like) AND (oral contraceptives). Finally, 9 eligible articles using as control other subtypes of invasive breast cancer and 7 articles using a healthy population as control were incorporated in the meta-analysis. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using fixed- or random-effects models according to the heterogeneity between studies. The case-control comparison using other subtypes of breast cancer as the control arm exhibited a significant association between OC use and TNBC (OR = 1.31, 95% CI = 1.18-1.45; Z=5.26, P<0.00001). These results were further confirmed by the case-control comparison using the healthy population as the control arm (OR = 1.21, 95% CI = 1.01-1.46; Z=2.04, P=0.04). The present meta-analysis indicated that women who use OCs have a greater risk of TNBC compared with women who do not. This conclusion prompts that women who used OCs should be examined more closely in population screenings of breast cancer, as they may benefit from prevention and early detection strategies.

Experimental verification of a 3D in vivo dose monitoring system based on EPID.

PURPOSE: To evaluate the Edose system, a novel three-dimensional (3D) in vivo dose monitoring system based on electronic portal imaging device (EPID), prior to clinical application, we analyzed the preliminary clinical data using Edose system in patients receiving intensity-modulated radiation therapy (IMRT). MATERIALS AND METHODS: After the physical modeling, the measured results from the Edose system were examined in homogeneous and inhomogeneous phantoms, respectively. To verify the accuracy of the Edose system, we compared its results with testing results from ionization chamber, measurement matrix (Delta4) and dosimetric films. The dosimetric performance of the Edose system was evaluated in 12 randomly selected patients with IMRT and VMAT, and the measured results were compared with the treatment plans. RESULTS: Compared with the measured results, the dose difference at the center of target volume was (0.12±0.91)% and (0.03±0.85)%, the γ pass rate was (94.18±1.69)% and (95.24±1.62)% (3mm/3%)for homogeneous and inhomogeneous phantoms, respectively. For IMRT patients, the dose difference at the center of target volume was (0.75±1.53)%, and the γ pass rates were (89.11±3.24)% (3mm/3%) and (96.40±1.47)% (3mm/5%), respectively. Compared with the results of DVH, the maximum differences of PTVs and mostly organs at risk were all within 3%. For VMAT patients, the γ pass rates were (93.04 ± 2.62)% (3mm/3%) and (97.92 ± 1.38)% (3mm/5%), respectively. CONCLUSIONS: In vivo dose monitoring may further improve the safety and quality assurance for radiation therapy. But rigorous clinical testing is required before putting the existing commercial systems into clinical application. In addition, more clinical experiences and better workflows for using the Edose system are needed.

Relapsed diffuse large B-cell lymphoma present different genomic profiles between early and late relapses.

Despite major advances in first-line treatment, a significant proportion of patients with diffuse large B-cell lymphoma (DLBCL) will experience treatment failure. Prognosis is particularly poor for relapses occurring less than one year after the end of first-line treatment (early relapses/ER) compared to those occurring more than one year after (late relapses/LR). To better understand genomic alterations underlying the delay of relapse, we identified copy number variations (CNVs) on 39 tumor samples from a homogeneous series of patients included in the Collaborative Trial in Relapsed Aggressive Lymphoma (CORAL) prospective study. To identify CNVs associated with ER or LR, we devised an original method based on Significance Analysis of Microarrays, a permutation-based method which allows control of false positives due to multiple testing. Deletions of CDKN2A/B (28%) and IBTK (23%) were frequent events in relapsed DLBCLs. We identified 56 protein-coding genes and 25 long non-coding RNAs with significantly differential CNVs distribution between ER and LR DLBCLs, with a false discovery rate < 0.05. In ER DLBCLs, CNVs were related to transcription regulation, cell cycle and apoptosis, with duplications of histone H1T (31%), deletions of DIABLO (26%), PTMS (21%) and CK2B (15%). In LR DLBCLs, CNVs were related to immune response, with deletions of B2M (20%) and CD58 (10%), cell proliferation regulation, with duplications of HES1 (25%) and DVL3 (20%), and transcription regulation, with MTERF4 deletions (20%). This study provides new insights into the genetic aberrations in relapsed DLBCLs and suggest pathway-targeted therapies in ER and LR DLBCLs.

Identification of master genes involved in liver key functions through transcriptomics and epigenomics of methyl donor deficiency in rat: relevance to nonalcoholic liver disease.

SCOPE: Our study aims to investigate molecular events associated to methyl donor deficiency (MDD) by analyzing the transcriptome and the methylome of MDD rats in liver. METHODS AND RESULTS: Twenty-one-day-old rats born to mothers fed either with a standard diet or a MDD diet during gestation and lactation were compared. From a total of 44 000 probes for 26 456 genes, we found two gene clusters in MDD rats whose expression levels had significant differences compared with controls: 3269 overexpressed (p < 0.0009) and 2841 underexpressed (p < 0.0004) genes. Modifications of DNA methylation were found in the promoter regions of 1032 genes out of 14 981 genes. Ontological analyses revealed that these genes are mainly involved in glucose and lipid metabolism, nervous system, coagulation, ER stress, and mitochondrial function. CONCLUSION: Putative master genes exhibiting changes in both gene expression and DNA methylation are limited to 266 genes and are mainly involved in the renin-angiotensin system (n = 3), mitochondrion metabolism (n = 18), and phospholipid homeostasis (n = 3). Most of these master genes participate in nonalcoholic fatty liver disease. The adverse effects of MDD on the metabolic process indicate the beneficial impact of folate and vitamin B12, especially during the perinatal period.