Effect of Nano-selenium on Biological Mechanism of Goblet Cells of the Small Intestine Within Laying Hen.

Dietary selenium intake within the normal physiological range is critical for various supporting biological functions. However, the effect of nano-selenium on biological mechanism of goblet cells associated with autophagy is largely unknown.The purpose of this study was to investigate the effect of nano-selenium on the mucosal immune-defense mechanism of goblet cells (GCs) in the small intestine of laying hens.The autophagy was determined by using specific markers. Nano-selenium-treated group of immunohistochemistry (IHC), immunofluorescence (IF), and western blotting (WB) results indicated the strong positive immune signaling of microtubule-associated light chain (LC3) within the mucosal surface of the small intestine. However, weak expression of LC3 was observed in the 3-methyladenine autophagy inhibitor (3-MA) group. IHC and IF staining results showed the opposite tendency for LC3 of sequestosome 1 (P62/SQSTM1). P62/SQSTM1 showed strong positive immune signaling within the mucosal surface of the small intestine of the 3-MAgroup, and weak immune signaling of P62/SQSTM1 in the nano-selenium-treated group. Moreover, pinpointing autophagy was involved in the mucosal production and enrichment of mucosal immunity of the GCs. The morphology and ultrastructure evidence showed that the mucus secretion of GCs was significantly increased after nano-selenium treatment confirmed by light and transmission electron microscopy. Besides that, immunostaining of IHC, IF and WB showed that autophagy enhanced the secretion of Mucin2 (Muc2) protein in nano-selenium-treated group. This work illustrates that the nano-selenium particle might enhance the mucosal immune-defense mechanism via the protective role of GCs for intestinal homeostasis through autophagy.

Specific Mutations in APC, with Prognostic Implications in Metastatic Colorectal Cancer.

PURPOSE: Loss-of-function mutations in the adenomatous polyposis coli (APC) gene are common in metastatic colorectal cancer (mCRC). However, the characteristic of APC specific mutations in mCRC is poorly understood. Here, we explored the clinical and molecular characteristics of N-terminal and C-terminal side APC mutations in Chinese patients with mCRC. MATERIALS AND METHODS: Hybrid capture-based next-generation sequencing was performed on tumor tissues from 275 mCRC pati-ents to detect mutations in 639 tumor-associated genes. The prognostic value and gene-pathway difference between APC specific mutations in mCRC patients were analyzed. RESULTS: APC mutations were highly clustered, accounting for 73% of all mCRC patients, and most of them were truncating mutations. The tumor mutation burden of the N-terminal side APC mutations group (n=76) was significantly lower than that of the C-terminal side group (n=123) (p < 0.001), further confirmed by the public database. Survival analysis showed that mCRC patients with N-terminus side APC mutations had longer overall survival than C-terminus side. Tumor gene pathway analysis showed that gene mutations in the RTK/RAS, Wnt and transforming growth factor ß signaling pathways of the C-terminal group were significantly higher than those of the N-terminal group (p < 0.05). Additionally, KRAS, AMER1, TGFBR2, and ARID1A driver mutations were more common in patients with C-terminal side APC mutations. CONCLUSION: APC specific mutations have potential function as mCRC prognostic biomarkers. There are obvious differences in the gene mutation patterns between the C-terminus and N-terminus APC mutations group, which may have certain guiding significance for the subsequent precise treatment of mCRC.

Pericytes protect rats and mice from sepsis-induced injuries by maintaining vascular reactivity and barrier function: implication of miRNAs and microvesicles.

BACKGROUND: Vascular hyporeactivity and leakage are key pathophysiologic features that produce multi-organ damage upon sepsis. We hypothesized that pericytes, a group of pluripotent cells that maintain vascular integrity and tension, are protective against sepsis via regulating vascular reactivity and permeability. METHODS: We conducted a series of in vivo experiments using wild-type (WT), platelet-derived growth factor receptor beta (PDGFR-ß)-Cre + mT/mG transgenic mice and Tie2-Cre + Cx43flox/flox mice to examine the relative contribution of pericytes in sepsis, either induced by cecal ligation and puncture (CLP) or lipopolysaccharide (LPS) challenge. In a separate set of experiments with Sprague-Dawley (SD) rats, pericytes were depleted using CP-673451, a selective PDGFR-ß inhibitor, at a dosage of 40 mg/(kg·d) for 7 consecutive days. Cultured pericytes, vascular endothelial cells (VECs) and vascular smooth muscle cells (VSMCs) were used for mechanistic investigations. The effects of pericytes and pericyte-derived microvesicles (PCMVs) and candidate miRNAs on vascular reactivity and barrier function were also examined. RESULTS: CLP and LPS induced severe injury/loss of pericytes, vascular hyporeactivity and leakage (P < 0.05). Transplantation with exogenous pericytes protected vascular reactivity and barrier function via microvessel colonization (P < 0.05). Cx43 knockout in either pericytes or VECs reduced pericyte colonization in microvessels (P < 0.05). Additionally, PCMVs transferred miR-145 and miR-132 to VSMCs and VECs, respectively, exerting a protective effect on vascular reactivity and barrier function after sepsis (P < 0.05). miR-145 primarily improved the contractile response of VSMCs by activating the sphingosine kinase 2 (Sphk2)/sphingosine-1-phosphate receptor (S1PR)1/phosphorylation of myosin light chain 20 pathway, whereas miR-132 effectively improved the barrier function of VECs by activating the Sphk2/S1PR2/zonula occludens-1 and vascular endothelial-cadherin pathways. CONCLUSIONS: Pericytes are protective against sepsis through regulating vascular reactivity and barrier function. Possible mechanisms include both direct colonization of microvasculature and secretion of PCMVs.

Genetic code expansion reveals aminoacylated lysine ubiquitination mediated by UBE2W.

Protein post-translational modification (PTM) regulates nearly every aspect of cellular processes in eukaryotes. However, the identification of new protein PTMs is very challenging. Here, using genetically encoded unnatural amino acids as chemical probes, we report the identification and validation of a previously unreported form of protein PTM, aminoacylated lysine ubiquitination, in which the modification occurs on the α-amine group of aminoacylated lysine. We identify more than 2,000 ubiquitination sites on all 20 aminoacylated lysines in two human cell lines. The modifications can mediate rapid protein degradation, complementing the canonical lysine ubiquitination-mediated proteome degradation. Furthermore, we demonstrate that the ubiquitin-conjugating enzyme UBE2W acts as a writer of aminoacylated lysine ubiquitination and facilitates the ubiquitination event on proteins. More broadly, the discovery and validation of aminoacylated lysine ubiquitination paves the way for the identification and verification of new protein PTMs with the genetic code expansion strategy.

Increased Prevalence of Thyroid Nodules Across Nearly 10 Years in Shanghai, China.

OBJECTIVE: This study aimed to determine whether the prevalence of thyroid nodules (TNs) increased due to modern lifestyles or other factors, despite the advances in screening and diagnostic tools. METHODS: This study included 3474 pairs of participants, who were matched by gender and age (±3 years) from two cross-sectional sampling surveys: (1) the program on the iodine nutritional status and related health status of residents in Shanghai in 2009; (2) the thyroid disease screening program for adults in Shanghai between 2017 and 2018. The prevalence of TNs and thyroid diseases in 2009 and 2017-2018 were compared, and the potential risk factors of TNs were detected. RESULTS: The prevalence of TNs in 2009 was 28.9%: 22.5% in males and 34.5% in females. In 2017, this increased to 43.8%: 37.9% in males and 49.1% in females. The prevalence of TNs significantly increased from 2009 to 2017 (odds ratio, 1.486; 95% confidence interval, 1.238-1.786). In addition, female gender, thyroid disease history, and age were the main risk factors for TNs after adjusting for confounders in the logistic regression across the time period. CONCLUSION: The prevalence of TNs significantly increased across nearly 10 years in Shanghai.

Probing the Role of Aurora Kinase A Threonylation with Site-Specific Lysine Threonylation.

Protein post-translational modifications play central roles in regulating protein functions. Lysine threonylation is a newly discovered reversible post-translational modification. However, the biological effect of lysine threonylation on proteins remains largely elusive. Here we report a chemical biology approach for site-specific incorporation of Nε-threonyllysine into proteins with high efficiency and investigate the biological effect of lysine threonylation on Aurora kinase A. Using this unnatural amino acid mutagenesis approach, we find that threonylation of Lys162 of Aurora kinase A inhibits its kinase activity both in vitro and in vivo and that the inhibitory effect can be reversed by the deacetylase Sirtuin 3, which removes the threonylated group from the lysine. Additionally, threonylation of Aurora kinase A makes its substrate p53 more stable in the cell. Therefore, our study demonstrates that site-specific lysine threonylation is a powerful method for probing the biological effect of protein threonylation.

Low Expression of AGPAT5 Is Associated With Clinical Stage and Poor Prognosis in Colorectal Cancer and Contributes to Tumour Progression.

Background: Colorectal cancer (CRC) has a high prevalence and poor prognosis. This study aimed to identify biomarkers related to the clinical stage (I-IV) of CRC. Methods: The LinkedOmics database was used as the discovery cohort, and two Gene Expression Omnibus (GEO) databases (GSE41258 and GSE422848) served as validation cohorts. The trend test of genes related to clinical stage (I-IV) of CRC patients was identified by the Jonckheere-Terpstra test. The cBioPortal database, Gene Expression Profiling Interactive Analysis (GEPIA) and PrognoScan databases were used to explore the expression change and prognostic value of clinical stage-related genes in CRC patients. CRC cells overexpressed AGPAT5 were constructed and used for cell counting kit-8 (CCK-8), flow cytometric, and wound healing assays in vitro. Results: We identified four clinical stage-related genes, GSR, AGPAT5, CRLF1, and NPR3, in CRC. The CNA frequencies of GSR, CRLF1, AGPAT5, and NPR3 occurred in 11%, 2.4%, 13%, and 3% of patients, respectively. The expression of GSR and AGPAT5 tended to decrease with CRC stage (I-IV) progression, and the expression of CRLF1 and NPR3 tended to increase with CRC stage (I-IV) progression. Compared with the normal group, AGPAT5 expression was markedly decreased in stage IV CRC. Higher GSR and AGPAT5 expression levels were associated with better overall survival (OS) and disease-free survival (DFS) in CRC patients. Lower CRLF1 and NPR3 expression levels were associated with better OS and DFS in CRC. GSR, CRLF1, AGPAT5, and NPR3 expression were related to CRC progression, microsatellite instability, and tumour purity in CRC. Furthermore, AGPAT5 was downregulated in CRC cell lines, and overexpression of AGPAT5 inhibited cell proliferation and migration and promoted cell apoptosis in CRC cells. Conclusion: Low AGPAT5 expression may serve as a poor prognostic factor and clinical stage biomarker in CRC. In addition, AGPAT5 acts as a tumour suppressor in CRC progression.

Circumventing glass vial and diluent effects on solution stability of small molecule analytes during analytical method development and validation.

Solution stability of analytes plays an important part in qualitative analysis, especially in conducting accurate, quantitative analyses. Sample diluents and glass vials as sample containers for HPLC analyses can play a critical role and should be evaluated during chromatographic method development. We have encountered several instances during pharmaceutical development where the glass vial/diluent combination has negatively impacted method performance. One case encompasses adsorption of piperazine, a secondary amine, to non-silanized glass vials, resulting in recovery failures during analytical method transfer. Two further cases describe the propensity for peracetylated C-aryl glucosides being subject chemical transformations relating to sample diluent. The first reports transesterification with methanol-based diluents and the second describes hydrolysis with acetonitrile/water diluents mediated by the mild alkalinity of certain brands of Type I borosilicate vials. A final case explores development of a related substance method, it was found that an impurity was prone to hydrolysis and another impurity with a primary amine tended to be adsorbed on glass vials. Diluents of appropriate pH and buffer strength were strategically selected to neutralize the mild alkalinity of the glass vials as well as to mitigate adsorption of the amine analyte on glass vials. As a result, excellent sample stability and reproducibility were achieved, regardless the quality and brand of Type I glass vials used. Here we present four case studies that demonstrate how the negative impact of Type I glass vials on those susceptible analytes can be effectively eliminated by using appropriate sample diluents, which is essential to ensure accurate analytical data and provide for a smooth method validation and transfer.

Directed-evolution of translation system for efficient unnatural amino acids incorporation and generalizable synthetic auxotroph construction.

Site-specific incorporation of unnatural amino acids (UAAs) with similar incorporation efficiency to that of natural amino acids (NAAs) and low background activity is extremely valuable for efficient synthesis of proteins with diverse new chemical functions and design of various synthetic auxotrophs. However, such efficient translation systems remain largely unknown in the literature. Here, we describe engineered chimeric phenylalanine systems that dramatically increase the yield of proteins bearing UAAs, through systematic engineering of the aminoacyl-tRNA synthetase and its respective cognate tRNA. These engineered synthetase/tRNA pairs allow single-site and multi-site incorporation of UAAs with efficiencies similar to those of NAAs and high fidelity. In addition, using the evolved chimeric phenylalanine system, we construct a series of E. coli strains whose growth is strictly dependent on exogenously supplied of UAAs. We further show that synthetic auxotrophic cells can grow robustly in living mice when UAAs are supplemented.

Evaluation of Serum 25-Hydroxyvitamin D3 and Bone Mineral Density in 268 Patients with Hip Fractures.

OBJECTIVE: The aim of the present study was to evaluate the relationship among vitamin D nutritional status, bone mineral density, and other factors in elderly patients with brittle hip fractures. METHODS: The present study was a retrospective analysis of 268 patients, 102 men (38.06%) and 166 women (61.94%), with brittle hip fractures admitted to the Hip Joint Center of Tianjin Hospital from February 2016 to June 2018. The median age of the patients was 74 years (range, 50-93 years). The patients were divided into three groups based on age: ≤69 years, 70-79 years, and ≥80 years. Serum 25-hydroxyvitamin D3 (25(OH) D3 ), parathyroid hormone (PTH), body mass index (BMI), and bone mineral density (BMD) of the lumbar spine, femoral neck, and hip were measured and statistically analyzed. RESULTS: The median serum 25(OH)D3 level of patients was 9.90 (range, 2.60-42.70) ng/mL; the proportion of deficiency was 89.18% and the deficiency was severe in 136 cases (49.25%). The proportion of vitamin D deficiency was significantly lower in men than in women (P = 0.013). With the increase of age, 25(OH)D3 levels gradually decreased (P = 0.044) and PTH levels gradually increased (P < 0.001). There was significantly negative correlation (P < 0.001) between the levels of serum 25(OH)D3 and PTH. There were 200 cases (74.63%) in which T-values of BMD were less than -2.5 in any part of the lumbar vertebrae, femoral neck, and hip. T-values in 74 cases (27.61%) were less than -2.5 in all three parts. The T-values of BMD in men were significantly higher than those in men (P < 0.001). With the increase of age, the femoral neck BMD in men gradually decreased (P = 0.016), and the femoral neck and hip BMD in female gradually decreased (P-value was 0.001 and 0.003, respectively). Multivariate analysis suggested that gender and BMI were independent risk factors for BMD, and vitamin D deficiency affected BMD. CONCLUSION: Vitamin D deficiency is common in patients with brittle hip fractures, especially in women. With the increase of age, vitamin D continues to decrease and PTH increases. The decrease of BMD in patients with hip fractures is the result of a combination of age, gender, BMI, and vitamin D content.

Differences and Correlation Analysis of Birth Weight and Overweight/Obesity in Shanghai Twin Cohort.

The objective of this study was to analyze differences in birth weight and overweight/obesity in a Shanghai twin cohort. We also wanted to study their association and explore possible risk factors for the discordance of overweight/obesity within twins. This was an internal case-control study designed for twins. The 2012 Shanghai Twin Registration System baseline survey data of a total of 3417 twin pairs were statistically analyzed using SPSS22 software. Results show that the body mass index (BMI) of the Shanghai twin population increased with age. Twins with a high birth weight had a higher BMI and a higher rate of overweight and obesity; 0- to 6-year-old twins, male twins and dizygotic (DZ) twins had higher rates of overweight/obesity than other groups. The greater the discordant birth weight rate of twins, the more obvious the difference in BMI (p < .05). There was a significant difference in overweight/obesity between twins with a relative difference of birth weight ≥15% in DZ twins (p < .05). DZ twins, male twins and 0- to 6-year-old twins were more likely to be discordant in overweight/obese than others. The discordant birth weight within twins was not a risk factor for discordant overweight/obesity. However, attention should be paid to childhood obesity, and appropriate interventions should be made at the appropriate time. Genetics may play an important role in the occurrence and development of overweight/obesity. In conclusion, discordant growth and development in the uterus early in life may not lead to discordant weight development in the future.

The development of a Chinese Healthy Eating Index for School-age Children and its Application in children from China Health and Nutrition Survey.

This study aimed to develop a Chinese Healthy Eating Index for School-age Children (CHEI-SC), apply it in the 2011 China Health and Nutrition Survey (CHNS) to assess dietary quality, and compared it with our former developed index named CHEI. Data of 3-day 24-hour diet recalls and household food inventory survey from 1600 school-age children in CHNS-2011 were used to develop the CHEI-SC, using the methods of standard portion size, energy-density-based approach, and least restrictive approach. The CHEI-SC included 19 components with a total score (T-score) ranging from 0 to 100. The investigated children had a median score of 49.6. Children with a higher T-score were more likely to have higher social economic status (SES), higher level of urbanisation, fewer family size, and regularly attending school. The CHEI-SC was able to assess dietary quality of Chinese school-age children, was sensitive to demographics, and more comprehensive and accurate than the CHEI.

Nearly perfect kinetic resolution of racemic o-nitrostyrene oxide by AuEH2, a microsomal epoxide hydrolase from Aspergillus usamii, with high enantio- and regio-selectivity.

Only a few known epoxide hydrolases (EHs) displayed activity towards o-nitrostyrene oxide (4a), presumably owing to the large steric hindrance caused by o-nitro substituent. Therefore, excavating EHs with high activity and enantio- and/or regio-selectivity towards racemic (rac-) 4a is essential but challenging. Here, AuEH2 from Aspergillus usamii was expressed in E. coli BL21(DE3). E. coli/Aueh2, an E. coli transformant expressing AuEH2, possessed EH activities of 16.2-184 U/g wet cell towards rac-styrene oxide (1a) and its derivatives (2a-13a), and the largest enantiomeric ratio of 96 towards rac-4a. The regioselectivity coefficients, ßR and ßS, of AuEH2 were determined to be 99.2% and 98.9%, suggesting that it regiopreferentially attacks the Cß in the oxirane rings of (R)- and (S)-4a. Then, the nearly perfect kinetic resolution of 20 mM rac-4a in pure water was carried out using 20 mg/mL wet cells of E. coli/Aueh2 at 25 °C for 50 min, retaining (S)-4a with over 99% ees and 48.9% yields, while producing (R)-o-nitrophenyl-1,2-ethanediol (4b) with 95.3% eep and 49.8% yieldp. To elucidate the molecular mechanism of AuEH2 with high enantiopreference for (R)-4a, its crystal structure was solved by X-ray diffraction and the molecular docking of AuEH2 with (R)- or (S)-4a was simulated.

Develop a circular RNA-related regulatory network associated with prognosis of gastric cancer.

BACKGROUND: In gastric cancer (GC), circular RNAs (circRNAs) mainly play an important role in miRNA sponge, which not only indicate long-term survival and prognosis but also increase resistance to the apoptosis. The purpose of the study is to explore new circRNAs and their underlying mechanisms in GC. METHOD: Through rigorous retrieval strategies, we used the sva package to analyze and identify differentially expressed circRNAs (DECs) from three Gene Expression Omnibus microarray datasets (GSE83521, GSE89143, and GSE78092). Online website CSCD and CircInteractome were used to reveal the binding sites between miRNAs and DECs. The possible target miRNAs of the DECs identified based on miRNAs, and Cytoscape was used to create a regulatory network of circRNA-miRNA-mRNA and identified the hub genes which were further validated using The Cancer Genome Atlas database and Human Protein Atlas. RESULTS: Twenty-eight DECs were obtained using the sva package. A regulatory network of circRNA-miRNA-mRNA (competing endogenous RNA) containing 15 circRNAs, 24 miRNAs, and 158 genes was identified. A protein-protein interaction network based on the 158 genes was established, and further determined that 10 hub genes (SKA1, ANLN, CHEK1, SKA3, TOP2A, BIRC5, RRM2, NCAPG2, FANCI, and RAD51) were associated with some cancer-related pathways based on the functional enrichment analysis. Finally, six hub genes (BIRC5, TOP2A, FANCI, NCAPG2, RAD51, and RRM2) were proven to influence the overall survival of GC. CONCLUSION: Our study established a circRNA-miRNA-mRNA regulatory network and defined six circRNA-related hub genes in GC, which could serve as potential therapeutic targets or prognostic biomarker for GC treatment.

Traditional Tibetan Medicine in Cancer Therapy by Targeting Apoptosis Pathways.

Cancer is a leading cause of death around the world. Apoptosis, one of the pathways of programmed cell death, is a promising target for cancer therapy. Traditional Tibetan medicine (TTM) has been used by Tibetan people for thousands of years, and many TTMs have been proven to be effective in the treatment of cancer. This paper summarized the medicinal plants with anticancer activity in the Tibetan traditional system of medicine by searching for Tibetan medicine monographs and drug standards and reviewing modern research literatures. Forty species were found to be effective in treating cancer. More importantly, some TTMs (e.g., Ophiocordyceps sinensis, Phyllanthus emblica L. and Rhodiola kirilowii (Regel) Maxim.) and their active ingredients (e.g., cordycepin, salidroside, and gallic acid) have been reported to possess anticancer activity by targeting some apoptosis pathways in cancer, such as Bcl-2/Bax, caspases, PI3K/Akt, JAK2/STAT3, MAPK, and AMPK. These herbs and natural compounds would be potential drug candidates for the treatment of cancer.

Acetylation-Dependent Deubiquitinase OTUD3 Controls MAVS Activation in Innate Antiviral Immunity.

Accurate regulation of innate immunity is necessary for the host to efficiently respond to invading pathogens and avoid excessive harmful immune pathology. Here we identified OTUD3 as an acetylation-dependent deubiquitinase that restricts innate antiviral immune signaling. OTUD3 deficiency in mice results in enhanced innate immunity, a diminished viral load, and morbidity. OTUD3 directly hydrolyzes lysine 63 (Lys63)-linked polyubiquitination of MAVS and thus shuts off innate antiviral immune response. Notably, the catalytic activity of OTUD3 relies on acetylation of its Lys129 residue. In response to virus infection, the acetylated Lys129 is removed by SIRT1, which promptly inactivates OTUD3 and thus allows timely induction of innate antiviral immunity. Importantly, acetyl-OTUD3 levels are inversely correlated with IFN-ß expression in influenza patients. These findings establish OTUD3 as a repressor of MAVS and uncover a previously unknown regulatory mechanism by which the catalytic activity of OTUD3 is tightly controlled to ensure timely activation of antiviral defense.

Chimeric design of pyrrolysyl-tRNA synthetase/tRNA pairs and canonical synthetase/tRNA pairs for genetic code expansion.

An orthogonal aminoacyl-tRNA synthetase/tRNA pair is a crucial prerequisite for site-specific incorporation of unnatural amino acids. Due to its high codon suppression efficiency and full orthogonality, the pyrrolysyl-tRNA synthetase/pyrrolysyl-tRNA pair is currently the ideal system for genetic code expansion in both eukaryotes and prokaryotes. There is a pressing need to discover or engineer other fully orthogonal translation systems. Here, through rational chimera design by transplanting the key orthogonal components from the pyrrolysine system, we create multiple chimeric tRNA synthetase/chimeric tRNA pairs, including chimera histidine, phenylalanine, and alanine systems. We further show that these engineered chimeric systems are orthogonal and highly efficient with comparable flexibility to the pyrrolysine system. Besides, the chimera phenylalanine system can incorporate a group of phenylalanine, tyrosine, and tryptophan analogues efficiently in both E. coli and mammalian cells. These aromatic amino acids analogous exhibit unique properties and characteristics, including fluorescence, post-translation modification.

A Gene-Related Nomogram for Preoperative Prediction of Lymph Node Metastasis in Colorectal Cancer.

Purpose: To develop and validate a gene-related nomogram for predicting the risk of lymph node (LN) metastasis preoperatively in patients with colorectal cancer (CRC). Methods: RNA-seq data of 581 CRC and 51 normal cases with clinical features were downloaded from TCGA database. In the evaluation cohort with 381 CRC cases, the LASSO regression was used to reduce dimensionality of gene signatures extracted to build gene score. A gene-related nomogram was performed based on the multivariable logistic regression analysis. The performance of the nomogram was assessed by the discrimination, calibration, and clinical usefulness not only in the evaluation, but also in the validation cohort with 200 CRC cases. Results: A total of 12,590 differentially expressed genes were selected, in which 59 candidates associated with LN metastasis in differentially expressed genes set were screened by LASSO to form the gene score. Based on the analysis of multivariate logistic regression, the gene-related nomogram showed good calibration and discrimination not only in the evaluation cohort (concordance-index 0.93; 95%CI 0.91-0.96), but also in the validation cohort (concordance-index 0.70; 95%CI 0.63-0.78). The decision curve analysis of the gene-related nomogram also provides constructive guidance for the design of operation plan, preoperatively. Conclusions: The presented genes nomogram may predict the LN metastasis in CRC patients, preoperatively. And 59 hub genes were defined related to LN metastasis of CRC, which can serve as treatment targets for the further study. Preoperative biopsy and gene analysis are needed to develop the operation plan in clinical practice.

Chemoselective Methionine Bioconjugation on a Polypeptide, Protein, and Proteome.

Methionine is one of the most hydrophobic, redox-sensitive, and one of the only two sulfur-containing amino acids on protein. Because of these biochemical properties, the methionine residue plays a central role in a variety of biological processes, such as metal coordination, antioxidant stress, and aging. However, studies on the molecular functions of methionine are much less common than the other primary sulfur-containing amino acid, cysteine. The limited number of publications on methionine-related studies is partially due to the lack of tools for methionine modification. Methionine bioconjugation offers a new strategy to decipher the biological function of methionine and expands the toolbox for protein functionalization in the context of the application, such as synthesizing proteins with novel properties and producing new biomaterials. The purpose of this Perspective is to highlight the biochemical properties and functions of methionine, list recent progress in the development of methionine bioconjugation reagents, and briefly demonstrate the application of these reagents on polypeptides, proteins, and proteomes.