Screening and identifying a novel M-MDSCs-related gene signature for predicting prognostic risk and immunotherapeutic responses in patients with lung adenocarcinoma.

Background: Lung adenocarcinoma (LUAD) shows intratumoral heterogeneity, a highly complex phenomenon that known to be a challenge during cancer therapy. Considering the key role of monocytic myeloid-derived suppressor cells (M-MDSCs) in the tumor microenvironment (TME), we aimed to build a prognostic risk model using M-MDSCs-related genes. Methods: M-MDSCs-related genes were extracted from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Utilized univariate survival analysis and random forest algorithm to screen candidate genes. A least absolute shrinkage and selection operator (LASSO) Cox regression analysis was selected to build the risk model. Patients were scored and classified into high- and low-risk groups based on the median risk scores. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis along with R packages "estimate" and "ssGSEA" were performed to reveal the mechanism of risk difference. Prognostic biomarkers and tumor mutation burden (TMB) were combined to predict the prognosis. Nomogram was carried out to predict the survival probability of patients in 1, 3, and 5 years. Results: 8 genes (VPREB3, TPBG, LRFN4, CD83, GIMAP6, PRMT8, WASF1, and F12) were identified as prognostic biomarkers. The GEO validation dataset demonstrated the risk model had good generalization effect. Significantly enrichment level of cell cycle-related pathway and lower content of CD8+ T cells infiltration in the high-risk group when compared to low-risk group. Morever, the patients were from the intersection of high-TMB and low-risk groups showed the best prognosis. The nomogram demonstrated good consistency with practical outcomes in predicting the survival rate over 1, 3, and 5 years. Conclusion: The risk model demonstrate good prognostic predictive ability. The patients from the intersection of low-risk and high-TMB groups are not only more sensitive response to but also more likely to benefit from immune-checkpoint-inhibitors (ICIs) treatment.

[Construction and anti-tumor efficacy of a pentameric peptide vaccine that targets S100A8].

Myeloid-derived suppressor cells(MDSC) play critical roles in immune escape of tumor. We hypothesized that elimination of tumor-induced MDSCs might help to block tumor growth. Therefore, we constructed a cholera toxin B based peptide vaccine that targets a MDSC surface marker S100A8. Immunized BALB/c mice with CTB-S100A8 plus aluminum hydroxide induced high titers of anti-S100A8 antibodies and reduced tumor burden significantly in 4T1 mice model. We also found the vaccination led to significant reduction of tumor-induced monocytic MDSC(M-MDSC), with no effect on innate MDSCs, dendritic cell(DC) and macrophage(Mφ), demonstrating that targeting tumor-induced MDSC may be a promising approach in cancer immunotherapy.

[Proteomics analysis of serum biomarkers in patients with pathological myopia].

OBJECTIVE: To identify the correlation between serum-based differentially expressed proteins and pathological myopia. METHODS: It was a case-control study. The serum of 30 pathological myopia patients and 30 age- and gender-matched normal controls were collected from Shanghai First People's Hospital affiliated to Shanghai Jiaotong University. These patients were divided into 4 groups including macular-off retinal detachment (8 cases), retinal geographic atrophy (5 cases), macular hole (11 cases) and choroidal neovascular (6 cases). The serum specimens of normal controls were used as immunogen to immune rabbits in order to prepare polyclonal antibodies. Purified by Protein A cartridge, these mixed antibodies were then combined with CNBr-activated Sepharose so as to synthesize affinity medium which was finally used to treat the serum specimens. According to the theory of antigen and antibody, common background proteins would be deleted. The remaining non-binding proteins were analyzed by capillary high-performance liquid chromatography and LTQ-MASS. Nonparametric statistical analysis was used to detect the correlation each differentially expressed protein. RESULTS: The result of HPLC and LTQ-MASS in 30 specimens of patients revealed 4 peaks of differentially expressed proteins including JTR (positive in 18 specimens, 60%), HP( positive in 11 specimens, 36.7%), HPX (positive in 10 specimens, 33.3%), APO (positive in 8 specimens, 26.7%). There were positive correlations between these 4 proteins (the correlation between TTR and HP, HPX, APO is r = 0.480, 0.577, 0.492; the correlation between HP and TTR, HPX, APO is r = 0.480, 0.783, 0.636; the correlation between HPX and TTR, HP, APO is r = 0.577, 0.783, 0.853; the correlation between APO and TTR, HP, HPX is r = 0.492, 0.636, 0.853; P < 0.05). In group of macular hole, TTR was positive expressed in 7 specimens while other differential proteins were low expression. In group of choroidal neovascular, TTR and HP were positive expressed in 6 specimens while HPX was significantly high in 5 specimens. In other two groups, the expression of 4 differential proteins was rather low. CONCLUSIONS: Screening molecular biomarkers by serum-based proteomics can efficiently exclude common proteins and find differential proteins correlated with pathological myopia. These differential proteins may become molecular biomarkers of pathological myopia in the future.

Comparative analysis of depurination catalyzed by ricin A-chain on synthetic 32mer and 25mer oligoribonucleotides mimicking the sarcin/ricin domain of the rat 28S rRNA and E. coli 23S rRNA.

Ricin A-chain can inactivate eukaryotic ribosomes, but exhibits no N-glycosidase activity on intact E. coli ribosomes. In the present research, in order to avoid using radiolabeled oligoribonucleotides, two kinds of synthetic 5'-FAM fluorescence-labeled oligoribonucleotide substrates were used to mimic the sarcin/ricin domains of rat 28S rRNA and E. coli 23S rRNA (32mer and 25mer, named as Rat FAM-SRD and E. coli FAM-SRD, respectively). Ricin A-chain was able to specifically release adenine from the first adenosine of the GAGA tetraloop and exhibited specific N-glycosidase activity under neutral and weak acidic conditions with both substrates. However, under more acidic conditions, ricin A-chain was able to release purines from other sites on eukaryotic substrates, but it retained specific depurination activity on prokaryotic substrates. At pH 5.0, the Michaelis constant (K(m)) for the reaction with Rat FAM-SRD (4.57+/-0.28microM) corresponded to that with E. coli FAM-SRD (4.64+/-0.26microM). However, the maximum velocity (V(max)) for ricin A-chain with Rat FAM-SRD was 0.5+/-0.024microM/min, which is higher than that with E. coli FAM-SRD (0.32+/-0.011microM/min).

[Raman spectroscopic study of human serum albumin interacting with 3-picolylamine].

Raman spectra of human serum albumin (HSA) and HSA-3-picolylamine complex were obtained. The spectra indicate the configuration and structural transformations of HSA. The results show that the secondary structure is main alpha-helix, and the binding of 3-picolylamine doesn't change the secondary structure. However, the binding changes the configuration of disulfide bonds, transforms a single tryptophan residue from exposed tryptophan residues to hydrophobic environment, and alters the microenvironment of tyrosine.

[A novel microbeads-based chemiluminescence immunoassay for detecting human thyrotropin].

AIM: To establish a low cost and sensitive microbeads-based chemiluminescence immunoassay (CLEIA) for detecting human thyrotropin. METHODS: Thyrotropin in sera was captured by an alkaline phosphase-labeled mAb against TSH beta subunit and a FITC-labeled mAb against TSH alpha subunit. Captured thyrotropin was then isolated with immuno-magnetic beads conjugated with anti-FITC antibody and then quantified by chemiluminescence using adamanatane amine as luminescent substrate. RESULTS: The sensitivity of this assay is 0.004 mIU/L. The intra-assay CV and the inter-assay CV of the assay were 7.45% and 10.45%, respectively. The recovery rate was 91.4% -102.4%. The examination result of the assay correlates well with that of ACS-180 system. CONCLUSION: The CLELA for detecting TSH is low-cost, sensitive, specific and stable, and therefore may have a promising prospect in clinical application.

Cloning and Distribution of rRP58, A Novel Neuronal Gene.

EST (AW055733) is a 3'-cDNA fragment specially expressed in rat brain. It is homologous to human and mouse RP58 gene, which is a transcriptional repressor gene. Primers were designed based on these two genes, and then two transcripts of rRP58 gene were got from male SD rat using RT-PCR method. The rRP58 protein is a C(2)H(2) type zinc finger protein, containing POZ domain at N-terminal and zinc finger domain (ZFD) at C-terminal. In addition, there is a highly acidic region between POZ and ZFD. POZ and ZFD were cloned, expressed and purified. Then, the antibodies to POZ and ZFD were prepared, and used to analyze distribution of alternative transcripts of rRP58.