SDF-1 promotes metastasis of NSCLC by enhancing chemoattraction of megakaryocytes through the PI3K/Akt signaling pathway.

Lung cancer (LC) is the leading cause of cancer-associated deaths worldwide, among which non-small-cell lung cancer (NSCLC) accounts for 80%. Stromal cell-derived factor-1 (SDF-1) inhibition results in a significant depletion of NSCLC metastasis. Additionally, SDF-1 is the only natural chemokine known to bind and activate the receptor CXCR4. Thus, we attempted to clarify the molecular mechanism of SDF-1 underlying NSCLC progression. Transwell migration, adhesion, and G-LISA assays were used to assess megakaryocytic chemotaxis in vitro and in vivo in terms of megakaryocytic migration, adherence, and RhoA activation, respectively. Western blotting was used to assess PI3K/Akt-associated protein abundances in MEG-01 cells and primary megakaryocytes under the indicated treatment. A hematology analyzer and flow cytometry were used to assess platelet counts in peripheral blood and newly formed platelet counts in Lewis LC mice under different treatments. Immunochemistry and flow cytometry were used to measure CD41+ megakaryocyte numbers in Lewis LC mouse tissue under different treatments. ELISA was used to measure serum TPO levels, and H&E staining was used to detect NSCLC metastasis.SDF-1 receptor knockdown suppressed megakaryocytic chemotaxis in Lewis LC mice. SDF-1 receptor inhibition suppressed megakaryocytic chemotaxis via the PI3K/Akt pathway. SDF-1 receptor knockdown suppressed CD41+ megakaryocyte numbers in vivo through PI3K/Akt signaling. SDF-1 receptor inhibition suppressed CD41+ megakaryocytes to hinder NSCLC metastasis. SDF-1 facilitates NSCLC metastasis by enhancing the chemoattraction of megakaryocytes via the PI3K/Akt signaling pathway, which may provide a potential new direction for seeking therapeutic plans for NSCLC.

Integrative learning in developing an immunologic lncRNA signature as a consensus risk-stratification tool for lung adenocarcinoma.

Background: In the tumor immune microenvironment, the contribution of innate and adaptive immune cells to tumor progression has been consistently demonstrated. However, reliable prognostic biomarkers for lung adenocarcinoma (LUAD) have not yet been identified. We thus developed and validated an immunologic long noncoding RNA (lncRNA) signature (ILLS) to facilitate the classification of patients with high and low risk and provide potential "made-to-measure" treatment choices. Methods: The LUAD data sets were obtained and processed from public databases of The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). The abundance of immune infiltration and its related pathways were calculated through consensus clustering, weighted gene coexpression network analysis (WGCNA), and an integrated ImmLnc to identify immune-related lncRNAs and extract immune-related prognostic lncRNAs. Based on the integrative procedure, the best algorithm composition was least absolute shrinkage and selection operator (LASSO) and stepwise Cox regression in both directions to develop the ILLS in the TCGA-LUAD data set and validate the predictive power of 4 independent data sets, GSE31210, GSE37745, GSE30219, and GSE50081 through survival analysis, receiver operating characteristic (ROC) analysis, and multivariate Cox regression. The concordance index (C-index) analysis was transversely compared with 49 published signatures in the above 5 data sets to further confirm its stability and superiority. Finally, drug sensitivity analysis was conducted to explore potential therapeutic agents. Results: Patients from the high-risk groups consistently had worse overall survival (OS) compared to the low-risk groups. ILLS proved to be an independent prognostic factor with favorable sensitivity and specificity. Among the 4 GEO data sets, compared to those reported in the other literature, ILLS maintained stable prediction ability and was more suitable as a consensus risk-stratification tool. However, The Cancer Immunome Atlas and IMvigor210 data sets demonstrated practical utility in recognizing target populations with effective immunotherapy, while the high-risk group exhibited potential targets for certain chemotherapy drugs, such as carmustine, etoposide, arsenic trioxide, and alectinib. Conclusions: ILLS demonstrated superior and stable prognostic prediction ability and thus has potential as a tool for assisting in risk classification and clinical decision-making in patients with LUAD.

Biotechnology Based Process for Production of a Disulfide-Bridged Peptide.

A disulfide-bridged peptide drug development candidate contained two oligopeptide chains with 11 and 12 natural amino acids joined by a disulfide bond at the N-terminal end. An efficient biotechnology based process for the production of the disulfide-bridged peptide was developed. Initially, the two individual oligopeptide chains were prepared separately by designing different fusion proteins and expressing them in recombinant E. coli. Enzymatic or chemical cleavage of the two fusion proteins provided the two individual oligopeptide chains which could be conjugated via disulfide bond by conventional chemical reaction to the disulfide-bridged peptide. A novel heterodimeric system to bring the two oligopeptide chains closer and induce disulfide bond formation was designed by taking advantage of the self-assembly of a leucine zipper system. The heterodimeric approach involved designing fusion proteins with the acidic and basic components of the leucine zipper, additional amino acids to optimize interaction between the individual chains, specific cleavage sites, specific tag to ensure separation, and two individual oligopeptide chains. Computer modeling was used to identify the nature and number of amino acid residue to be inserted between the leucine zipper and oligopeptides for optimum interaction. Cloning and expression in rec E. coli, fermentation, followed by cell disruption resulted in the formation of heterodimeric protein with the interchain disulfide bond. Separation of the desired heterodimeric protein, followed by specific cleavage at methionine by cyanogen bromide provided the disulfide-bridged peptide.