Deep whole-genome analysis of 494 hepatocellular carcinomas.

Over half of hepatocellular carcinoma (HCC) cases diagnosed worldwide are in China1-3. However, whole-genome analysis of hepatitis B virus (HBV)-associated HCC in Chinese individuals is limited4-8, with current analyses of HCC mainly from non-HBV-enriched populations9,10. Here we initiated the Chinese Liver Cancer Atlas (CLCA) project and performed deep whole-genome sequencing (average depth, 120×) of 494 HCC tumours. We identified 6 coding and 28 non-coding previously undescribed driver candidates. Five previously undescribed mutational signatures were found, including aristolochic-acid-associated indel and doublet base signatures, and a single-base-substitution signature that we termed SBS_H8. Pentanucleotide context analysis and experimental validation confirmed that SBS_H8 was distinct to the aristolochic-acid-associated SBS22. Notably, HBV integrations could take the form of extrachromosomal circular DNA, resulting in elevated copy numbers and gene expression. Our high-depth data also enabled us to characterize subclonal clustered alterations, including chromothripsis, chromoplexy and kataegis, suggesting that these catastrophic events could also occur in late stages of hepatocarcinogenesis. Pathway analysis of all classes of alterations further linked non-coding mutations to dysregulation of liver metabolism. Finally, we performed in vitro and in vivo assays to show that fibrinogen alpha chain (FGA), determined as both a candidate coding and non-coding driver, regulates HCC progression and metastasis. Our CLCA study depicts a detailed genomic landscape and evolutionary history of HCC in Chinese individuals, providing important clinical implications.

Hyperactivation of ß-catenin signal in hepatocellular carcinoma recruits myeloid-derived suppressor cells through PF4-CXCR3 axis.

The high mutation rate of CTNNB1 (37 %) and Wnt-ß-catenin signal-associated genes (54 %) has been notified in hepatocellular carcinoma (HCC). The activation of Wnt-ß-catenin signal pathway was reported to be associated with an immune "desert" phenotype, but the underlying mechanism remains unclear. Here we mainly employed orthotopic HCC models to explore on it. Mass cytometry depicted the immune contexture of orthotopic HCC syngeneic grafts, unveiling that the exogenous expression of ß-catenin significantly increased the percentage of myeloid-derived suppressor cells (MDSCs) and decreased the percentage of CD8+ T-cells. Flow cytometry and immunohistochemistry further confirmed the findings. The protein microarray analysis, Western blot and PCR identified PF4 as its downstream regulating cytokine. Intratumorally injection of cytokine PF4 enhanced the accumulation of MDSCs. Knockout of PF4 abolished the effect of ß-catenin on recruiting MDSCs. Chromatin immunoprecipitation and luciferase reporter assay demonstrated that ß-catenin increases the mRNA level of PF4 via binding to PF4's promoter region. In vitro chemotaxis assay and in vivo administration of specific inhibitors identified CXCR3 on MDSCs as receptor for recruiting PF4. Lastly, the significant correlations across ß-catenin, PF4 and MDSCs and CD8+ T-cells infiltration were verified in HCC clinical samples. Our results unveiled HCC tumor cell intrinsic hyperactivation of ß-catenin can recruit MDSC through PF4-CXCR3, which contributes to the formation of immune "desert" phenotype. Our study provided new insights into the development of immunotherapeutic strategy of HCC with CTNNB1 mutation. SIGNIFICANCE: This study identifies PF4-CXCR3-MDSCs as a downstream mechanism underlying CTNNB1 mutation associated immune "desert" phenotype.

Probiotic intervention benefits multiple neural behaviors in older adults with mild cognitive impairment.

Probiotic supplements were shown to improve cognitive function in Alzheimer's disease (AD) patients. However, it is still unclear whether this applies to older individuals with mild cognitive impairment (MCI). We aimed to explore the effects of probiotic supplementation on multiple neural behaviors in older adults with MCI. Forty-two MCI patients (age > 60 years) were randomly divided into two groups and consumed either probiotics (n=21) or placebo (n=21) for 12 weeks. Various scale scores, gut microbiota measures and serological indicators were recorded pre- and posttreatment. After 12 weeks of intervention, cognitive function and sleep quality were improved in the probiotic group compared with those in the control group, and the underlying mechanisms were associated with changes in the intestinal microbiota. In conclusion, our study demonstrated that probiotic treatment enhanced cognitive function and sleep quality in older MCI patients, thus providing important insights into the clinical prevention and treatment of MCI.

Integrated Multi-Omics Landscape of Liver Metastases.

BACKGROUND & AIMS: Lack of thorough knowledge about the complicated immune microenvironment (IM) within a variety of liver metastases (LMs) leads to inappropriate treatment and unsatisfactory prognosis. We aimed to characterize IM subtypes and investigate potential mechanisms in LMs. METHODS: Mass cytometry was applied to characterize immune landscape of a primary liver cancers and liver metastases cohort. Transcriptomic and whole-exome sequencing were used to explore potential mechanisms across distinct IM subtypes. Single-cell transcriptomic sequencing, multiplex fluorescent immunohistochemistry, cell culture, mouse model, Western blot, quantitative polymerase chain reaction, and immunohistochemistry were used for validation. RESULTS: Five IM subtypes were revealed in 100 LMs and 50 primary liver cancers. Patients featured terminally exhausted (IM1) or rare T-cell-inflamed (IM2 and IM3) immune characteristics showed worse outcome. Increased intratumor heterogeneity, enriched somatic TP53, KRAS, APC, and PIK3CA mutations and hyperactivated hypoxia signaling accounted for the formation of vicious subtypes. SLC2A1 promoted immune suppression and desert via increasing proportion of Spp1+ macrophages and their inhibitory interactions with T cells in liver metastatic lesions. Furthermore, SLC2A1 promoted immune escape and LM through inducing regulatory T cells, including regulatory T cells and LAG3+CD4+ T cells in primary colorectal cancer. CONCLUSIONS: The study provided integrated multi-omics landscape of LM, uncovering potential mechanisms for vicious IM subtypes and confirming the roles of SLC2A1 in regulating tumor microenvironment remodeling in both primary tumor and LM lesions.

Spatiotemporal genomic analysis reveals distinct molecular features in recurrent stage I non-small cell lung cancers.

Stage I non-small cell lung cancer (NSCLC) presents diverse outcomes. To identify molecular features leading to tumor recurrence in early-stage NSCLC, we perform multiregional whole-exome sequencing (WES), RNA sequencing, and plasma-targeted circulating tumor DNA (ctDNA) detection analysis between recurrent and recurrent-free stage I NSCLC patients (CHN-P cohort) who had undergone R0 resection with a median 5-year follow-up time. Integrated analysis indicates that the multidimensional clinical and genomic model can stratify the prognosis of stage I NSCLC in both CHN-P and EUR-T cohorts and correlates with positive pre-surgical deep next generation sequencing (NGS) ctDNA detection. Increased genomic instability related to DNA interstrand crosslinks and double-strand break repair processes is significantly associated with early tumor relapse. This study reveals important molecular insights into stage I NSCLC and may inform clinical postoperative treatment and follow-up strategies.

Whole-Exome Sequencing on Circulating Tumor Cells Explores Platinum-Drug Resistance Mutations in Advanced Non-small Cell Lung Cancer.

Circulating tumor cells (CTCs) have important applications in clinical practice on early tumor diagnosis, prognostic prediction, and treatment evaluation. Platinum-based chemotherapy is a fundamental treatment for non-small cell lung cancer (NSCLC) patients who are not suitable for targeted drug therapies. However, most patients progressed after a period of treatment. Therefore, revealing the genetic information contributing to drug resistance and tumor metastasis in CTCs is valuable for treatment adjustment. In this study, we enrolled nine NSCLC patients with platinum-based chemotherapy resistance. For each patient, 10 CTCs were isolated when progression occurred to perform single cell-level whole-exome sequencing (WES). Meanwhile the patients' paired primary-diagnosed formalin-fixed and paraffin-embedded samples and progressive biopsy specimens were also selected to perform WES. Comparisons of distinct mutation profiles between primary and progressive specimens as well as CTCs reflected different evolutionary mechanisms between CTC and lymph node metastasis, embodied in a higher proportion of mutations in CTCs shared with paired progressive lung tumor and hydrothorax specimens (4.4-33.3%) than with progressive lymphatic node samples (0.6-11.8%). Functional annotation showed that CTCs not only harbored cancer-driver gene mutations, including frequent mutations of EGFR and TP53 shared with primary and/or progressive tumors, but also particularly harbored cell cycle-regulated or stem cell-related gene mutations, including SHKBP1, NUMA1, ZNF143, MUC16, ORC1, PON1, PELP1, etc., most of which derived from primary tumor samples and played crucial roles in chemo-drug resistance and metastasis for NSCLCs. Thus, detection of genetic information in CTCs is a feasible strategy for studying drug resistance and discovering new drug targets when progressive tumor specimens were unavailable.

Posttraumatic stress disorder and professional burnout among local government staff seven years after the Wenchuan earthquake in China: A longitudinal study.

Although local government staff are crucial in post-quake reconstruction, their long-term psychological and professional consequences remain unclear. This longitudinal study investigated changes of posttraumatic stress disorder (PTSD) and professional burnout over seven years, and their underlying relationship. The study assessed 250 staff at one year (T1y) after the earthquake, and 162 (64.8 %) were followed up at seven years (T7y). PTSD and professional burnout were assessed with the Short Screening Scale for DSM-IV PTSD and the burnout subscale of Professional Quality of Life Scale (ProQOL), respectively, at both time points. Longitudinal changes in PTSD and burnout were examined and cross-lagged panel analyses were conducted to test the relationship between PTSD and burnout. The rates of positive cases of PTSD screening were 23.2 % at T1y and 11.1 % at T7y. The percentages of moderate burnout were 61.7 % at T1y and 23.5 % at T7y. Scores of PTSD (z = -5.70, p < 0.001) and burnout (t = 10.07, p < 0.001) from T1y to T7y decreased. The cross-lagged analysis indicated that burnout at T1y predicted PTSD at T7y (ß = 0.19, p = 0.025). In conclusion, the Wenchuan earthquake has long-lasting negative effects on local government staff, although they can recover over time. Interventions to reduce professional burnout after disaster may does be beneficial to decrease the risk of PTSD in the long run.

Mutant Allele Frequency-Based Intra-Tumoral Genetic Heterogeneity Related to the Tumor Shrinkage Mode After Neoadjuvant Chemotherapy in Breast Cancer Patients.

The shrinkage mode of tumor extent after neoadjuvant chemotherapy (NAC) is an important index to evaluate the odds of breast-conserving surgery. However, there is no sufficient measurement to predict the shrinkage mode after NAC. In this study, we analyzed 24 patients' formalin-fixed, paraffin-embedded samples before and after treatment and analyzed 456 cancer-related genes panel by using target next-generation sequencing. Meanwhile, the pathological shrinkage mode was reconstructed in three dimensions after surgery, and the genetic heterogeneity level was estimated by mutant-allele tumor heterogeneity (MATH). We measured the genetic intra-tumor heterogeneity and explored its correlation with the shrinkage mode after NAC. A total of 17 matched pair samples of primary tumor tissue and residual tumor tissue were successfully accessed. It was found that the most common mutated genes were TP53 and PIK3CA in both samples before and after NAC, and no recurrent mutations were significantly associated with the shrinkage mode. Besides, the MATH value of formalin-fixed, paraffin-embedded samples before and after NAC was analyzed by the area under the curve of the receiver operating characteristic, and it is feasible to classify patients into concentric shrinkage mode and non-concentric shrinkage mode in NAC based on the MATH threshold of 58. Our findings indicate that the MATH value was associated with the shrinkage mode of breast cancer in a non-linear model. Patients with the MATH value below the threshold of 58 before and after NAC displayed a concentric shrinkage mode. The area under the curve was 0.89, with a sensitivity of 0.69 and specificity of 1. Our study might provide a promising application of intra-tumor heterogeneity that is measured by MATH to make a choice of surgery.

A longitudinal study on emotional distress among local government staff seven years after the 2008 Wenchuan earthquake in China.

BACKGROUND: The current study examined the change in local government staff's emotional distress over 7 years after the 2008 Wenchuan earthquake, and the influence of earthquake exposure and professional quality of life (ProQOL) on emotional distress. METHODS: This longitudinal study assessed 250 participants at 1 year after the earthquake; 162 (64.8%) were followed up at 7 years. Emotional distress was assessed with the Self-Reporting Questionnaire (SRQ) at both time points. We assessed ProQOL, including compassion satisfaction, burnout, and secondary traumatic stress, and earthquake exposure at 1 year. Wilcoxon signed-rank tests were performed to test longitudinal changes in emotional distress. Hierarchical multiple regression was conducted to examine the effect of earthquake exposure and ProQOL. RESULTS: The positive screening rate of emotional distress (SRQ ≥ 8) was 37.6 and 15.4% at one and 7 years, respectively. Emotional distress scores declined over time (p < 0.001). Earthquake exposure and ProQOL predicted one-year (ps < 0.05) but not seven-year emotional distress, whereas burnout predicted both one-year (p = 0.018) and seven-year (p = 0.047) emotional distress. CONCLUSIONS: Although emotional distress can recover over time, it persists even 7 years later. Actions to reduce burnout during the early stage of post-disaster rescue have long-term benefits to staff's psychological outcomes.

Genetic profiling of primary and secondary tumors from patients with lung adenocarcinoma and bone metastases reveals targeted therapy options.

BACKGROUND: Patients newly diagnosed with lung adenocarcinoma with bone metastases (LABM) have poor survival rates after treatment with conventional therapies. To improve outcomes, we retrospectively investigated whether the application of a more comprehensive genetic test of tumor biopsies samples from LABM patients could provide the basis for treatment with more effective tyrosine kinase inhibitors (TKIs) regimens. METHODS: Fine needle biopsies were taken from the primary tumor (PT) and a secondary bone metastasis (BM) of 17 LABM patients before treatment. Simple genetic profiles for selecting therapies were initially obtained using an ARMS-PCR test for EGFR and ALK fusion mutations. More detailed genetic profiles of somatic exon SNVs and CNVs in 457 cancer-related genes were retrospectively derived using capture single molecule amplification and resequencing technology (capSMART). RESULTS: ARMS-PCR identified 14 EGFR positive, 3 EGFR negative and 1 ALK fusion positive patient. A therapy regimen incorporating TKIs Gefitinib and Crizotinib was offered to the EGFR and ALK fusion positive patients, respectively. With the exception of two patients, molecular profiling of matching PT and BM biopsies identified a highly shared somatic variant fingerprint, although the BMs exhibited additional genomic instability. In six of 13 EGFR positive patients and in all three EGFR negative patients, examination of the genetic profiles identified additional clinically significant mutations that are known or experimental drug targets for treatment of lung cancer. CONCLUSION: Our findings firstly suggest that treatment regimens based on comprehensive genetic assessment of newly diagnosed LABM patients should target both the PT and secondary BMs, including rogue clones with potential to form new BMs. Second, the additional information gained should allow clinicians to design and implement more personalized treatment regimens and potentially improve outcomes for LABM patients.

Contributions of Zea mays subspecies mexicana haplotypes to modern maize.

Maize was domesticated from lowland teosinte (Zea mays ssp. parviglumis), but the contribution of highland teosinte (Zea mays ssp. mexicana, hereafter mexicana) to modern maize is not clear. Here, two genomes for Mo17 (a modern maize inbred) and mexicana are assembled using a meta-assembly strategy after sequencing of 10 lines derived from a maize-teosinte cross. Comparative analyses reveal a high level of diversity between Mo17, B73, and mexicana, including three Mb-size structural rearrangements. The maize spontaneous mutation rate is estimated to be 2.17 × 10-8 ~3.87 × 10-8 per site per generation with a nonrandom distribution across the genome. A higher deleterious mutation rate is observed in the pericentromeric regions, and might be caused by differences in recombination frequency. Over 10% of the maize genome shows evidence of introgression from the mexicana genome, suggesting that mexicana contributed to maize adaptation and improvement. Our data offer a rich resource for constructing the pan-genome of Zea mays and genetic improvement of modern maize varieties.

Comparative genomic and functional analyses: unearthing the diversity and specificity of nematicidal factors in Pseudomonas putida strain 1A00316.

We isolated Pseudomonas putida (P. putida) strain 1A00316 from Antarctica. This bacterium has a high efficiency against Meloidogyne incognita (M. incognita) in vitro and under greenhouse conditions. The complete genome of P. putida 1A00316 was sequenced using PacBio single molecule real-time (SMRT) technology. A comparative genomic analysis of 16 Pseudomonas strains revealed that although P. putida 1A00316 belonged to P. putida, it was phenotypically more similar to nematicidal Pseudomonas fluorescens (P. fluorescens) strains. We characterized the diversity and specificity of nematicidal factors in P. putida 1A00316 with comparative genomics and functional analysis, and found that P. putida 1A00316 has diverse nematicidal factors including protein alkaline metalloproteinase AprA and two secondary metabolites, hydrogen cyanide and cyclo-(l-isoleucyl-l-proline). We show for the first time that cyclo-(l-isoleucyl-l-proline) exhibit nematicidal activity in P. putida. Interestingly, our study had not detected common nematicidal factors such as 2,4-diacetylphloroglucinol (2,4-DAPG) and pyrrolnitrin in P. putida 1A00316. The results of the present study reveal the diversity and specificity of nematicidal factors in P. putida strain 1A00316.

Functional analysis of long intergenic non-coding RNAs in phosphate-starved rice using competing endogenous RNA network.

Long intergenic non-coding RNAs (lincRNAs) may play widespread roles in gene regulation and other biological processes, however, a systematic examination of the functions of lincRNAs in the biological responses of rice to phosphate (Pi) starvation has not been performed. Here, we used a computational method to predict the functions of lincRNAs in Pi-starved rice. Overall, 3,170 lincRNA loci were identified using RNA sequencing data from the roots and shoots of control and Pi-starved rice. A competing endogenous RNA (ceRNA) network was constructed for each tissue by considering the competing relationships between lincRNAs and genes, and the correlations between the expression levels of RNAs in ceRNA pairs. Enrichment analyses showed that most of the communities in the networks were related to the biological processes of Pi starvation. The lincRNAs in the two tissues were individually functionally annotated based on the ceRNA networks, and the differentially expressed lincRNAs were biologically meaningful. For example, XLOC_026030 was upregulated from 3 days after Pi starvation, and its functional annotation was 'cellular response to Pi starvation'. In conclusion, we systematically annotated lincRNAs in rice and identified those involved in the biological response to Pi starvation.

[Primary analysis of reasons and countermeasures for 19 cases infection of severe acute respiratory syndrome (SARS) in health care workers].

OBJECTIVE: To analyse the reason and countermeasure for the infection of severe acute respiratory syndrome (SARS) in health care workers, to provide reference for the health care workers to control infection of SARS. METHODS: To analyse retrospectively the reason and countermeasure 19 infective cases of SARS among the health care workers in our hospital from 16th March, 2003 to 3rd May, 2003. RESULTS: Except for 4 fellow-doctors were infected by close contact in a same dormitory, all others were infected on work-station of close contact with SARS patients, there were no more cross-infection among the health care workers. CONCLUSION: It is important to improve the protection even for the health care workers without contact of SARS patients, and it's necessary to wear mask, goggles, and gloves, health care workers with contact with SARS patients must be separated according the extent of contact separately, and draw guideline in advance.