Background/Aims: Extensive studies have demonstrated that Bleomycin (BLM) is a glycopeptide antibiotic that has been used as an anticancer chemotherapeutic reagent. It can induce both single- and double-strand DNA damage, inhibit synthesis of DNA, suppress proliferation, and induce apoptosis in cancer cells. Smad signaling transducers are considered as important molecules in tumor development and progression, and may closely be related to the biological behaviors of some malignant carcinomas, including gastric cancer. Methods: The effects of different concentrations of BLM on the proliferation, cell cycle, apoptosis, migration, and invasion on gastric cancer cell lines MKN45 and AGS were assayed by using CCK-8 assay, Annexin V/PI double staining, PI staining, and transwell assay. Western blot and Immunohistochemistry were applied to analyze the potential mechanism(s). Results: BLM treatment resulted in a low proliferation, high apoptosis, low migration and invasion in MKN45 and AGS cells. Furthermore, the possible mechanisms underlying that Smad3 activity could be changed after binding with BLM, and subsequently the Smad signaling pathway had a cascade response. Conclusion: These results highlight BLM as an exciting theme for gastric cancer treatment, which may represent an effective clinical therapeutic reagent for gastric cancer patients.
In addition to genomic mutations, RNA editing is another major mechanism creating sequence variations in proteins by introducing nucleotide changes in mRNA sequences. Deregulated RNA editing contributes to different types of human diseases, including cancers. Here we report that peptides generated as a consequence of RNA editing are indeed naturally presented by human leukocyte antigen (HLA) molecules. We provide evidence that effector CD8+ T cells specific for edited peptides derived from cyclin I are present in human tumours and attack tumour cells that are presenting these epitopes. We show that subpopulations of cancer patients have increased peptide levels and that levels of edited RNA correlate with peptide copy numbers. These findings demonstrate that RNA editing extends the classes of HLA presented self-antigens and that these antigens can be recognised by the immune system.
As a common cause of cancer-related deaths in women, BRCA (breast cancer) shows complexity and requires precise biomarkers and treatment methods. This study delves into the molecular makeup of BRCA, focusing on immune profiles, molecular subtypes, gene expression and single-cell analysis. XCell was used to assess immune infiltration based on TCGA (the Cancer Genome Atlas) data and the clustering analysis was made. Differentially expressed genes were examined in distinct clusters, and the WGCNA (weighted correlation network analysis) was made to establish co-expression networks. The prognostic models were developed by Cox and LASSO-Cox regression. The clustering analysis, GSEA (Gene set enrichment analysis), GSVA (gene set variation analysis) and communication analysis of the single-cell dataset GSE161529 were performed to investigate the functional relevance. Real-time polymerase chain reaction (RT-PCR) was employed for evaluating gene expression. The results revealed significant differences in immune cell infiltration between two clusters (C1 and C2). C2 had poorer survival outcomes, which was associated with higher expression of immune checkpoints PD1 and PD-L1. The gene modules identified via WGCNA were correlated with the immune-based subtypes. Then, a prognostic model comprising seven genes (ACSL1, ABCB5, XG, ADH4, OPN4, NPR3, NLGN1) was used to divide patients into high- and low-risk subgroups. The high-risk group had worse prognosis and higher scores of TIDE (Tumor Immune Dysfunction and Exclusion). The single-cell analysis depicted the immune landscape. Macrophages and endothelial cells exhibited higher AUCell scores. In cellular communication analysis, notably significant ligand-receptor interactions of HLA-DRA-> CD4 and TNFSF13B-> HLA-DPB1 were observed. The proportion of endothelial cells was correlated with risk scores. Finally, RT-PCR results illustrated the expression of seven genes in BRCA specimens. The integrative analysis provides new insights into molecular complexities of BRCA. Immune profiles and gene signatures hold potential for improving stratification of BRCA patients and guiding the development of personalized immunotherapy strategies.
Nine tumor and various potential biomarkers were measured and combined the information to diagnose disease, all patients accepted fiber bronchoscopy brush liquid based cytologyand histopathology examination in order to reliably detect lung cancer. The samples from 314 Chinese lung cancer patients were obtained and CK5/6, P63, P40, CK7, TTF-1, NapsinA CD56, Syn and CgA were measured with the immunohistochemical SP method and analyzed correlation of the expression of these markers with pathological and clinical features of squamous cell carcinoma, adenocarcinoma, and small cell lung carcinoma. Squamous cell carcinoma, adenocarcinoma and small cell carcinoma were 61 cases, 114 cases and 139 cases,CK5/6 and P63 expression were more frequent in squamous cell carcinoma, with sensitivity and specificity of 77.05 % and 96.44 %, 83.61 % and 88.93 %,and compared with adenocarcinoma and small cell carcinoma difference was statistically significant (P<0.05), The incidences of a positive P40 expression were 100 % in squamous cell carcinoma, with specificity of 98.81 %.CK7, TTF-1 and NapsinA expression were more frequent in adenocarcinoma, with sensitivity and specificity of 85.09 % and 78.69 %, 79.82 % and 93.44 %, 56.14 % and 95.08 %, and compared with squamous cell carcinoma and small cell carcinoma difference was statistically significant (P<0.05). TTF-1, Syn, CgA and CD56 expression were more frequent in adenocarcinoma, with sensitivity and specificity of 86.33 % and 93.44 %, 89.21 % and 98.36 %, 74.10 % and 100 %, 96.40 % and 96.72 %. The combined detection of CK5/6, P63 and P40 were more useful and specific in differentiating squamous cell carcinoma. CK7, TTF-1 and NapsinA were more useful and specific in differentiating lung adenocarcinoma. The impaired CD56, TTF-1, Syn and CgA reflects the progression of small cell lung cancer.
Background ADAR1, the major enzyme for RNA editing, has emerged as a tumor-intrinsic key determinant for cancer immunotherapy efficacy through modulating interferon-mediated innate immunity. However, the role of ADAR1 in innate immune cells such as macrophages remains unknown. Methods We first analyzed publicly accessible patient-derived single-cell RNA-sequencing and perturbed RNA sequencing data to elucidate the ADAR1 expression and function in macrophages. Subsequently, we evaluated the combined effects of ADAR1 conditional knockout in macrophages and interferon (IFN)-γ treatment on tumor growth in three distinct disease mouse models: LLC for lung cancer, B16-F10 for melanoma, and MC38 for colon cancer. To gain the mechanistic insights, we performed human cytokine arrays to identify differentially secreted cytokines in response to ADAR1 perturbations in THP-1 cells. Furthermore, we examined the effects of ADAR1 loss and IFN-γ treatment on vessel formation through immunohistochemical staining of mouse tumor sections and tube-forming experiments using HUVEC and SVEC4-10 cells. We also assessed the effects on CD8 + T cells using immunofluorescent and immunohistochemical staining and flow cytometry. To explore the translational potential, we examined the consequences of injecting ADAR1-deficient macrophages alongside IFN-γ treatment on tumor growth in LLC-tumor-bearing mice. Results Our analysis on public data suggests that ADAR1 loss in macrophages promotes antitumor immunity as in cancer cells. Indeed, ADAR1 loss in macrophages combined with IFN-γ treatment results in tumor regression in diverse disease mouse models. Mechanistically, the loss of ADAR1 in macrophages leads to the differential secretion of key cytokines: it inhibits the translation of CCL20, GDF15, IL-18BP, and TIM-3 by activating PKR/EIF2α signaling but increases the secretion of IFN-γ through transcriptional upregulation and interleukin (IL)-18 due to the 5'UTR uORF. Consequently, decreased CCL20 and GDF15 and increased IFN-γ suppress angiogenesis, while decreased IL-18BP and TIM-3 and increased IL-18 induce antitumor immunity by enhancing cytotoxicity of CD8 + T cells. We further demonstrate that combination therapy of injecting ADAR1-deficient macrophages and IFN-γ effectively suppresses tumors in vivo. Conclusion This study provides a comprehensive elucidation of how ADAR1 loss within macrophages contributes to the establishment of an antitumor microenvironment, suggesting the therapeutic potential of targeting ADAR1 beyond the scope of cancer cells.