Background: The tumor microenvironment plays an important role in the occurrence and development of tumors. However, there are gaps in understanding the molecular and cellular interactions between tumor cells and the immune tumor microenvironment (TME). The aim of this study was to identify a novel gene that played an important role in the tumor microenvironment of lung adenocarcinoma (LUAD). Methods: The gene expression profile and clinical data for LUAD were downloaded from TCGA database. First, we used the ESTIMATE algorithm to evaluate the immune and stromal scores accordingly. Also, we analyzed differentially expressed immune-related genes (IRGs) in the high and low immune/stromal score groups. Then, we used the protein–protein interaction network (PPI network) and a univariate Cox regression analysis to identify the hub gene. After that, we analyzed the relationship between CSF2RB expression and TNM stage/prognosis. Furthermore, gene set enrichment analysis (GSEA) was used to analyze the pathway regulated by CSF2RB and the Pearson correlation analysis method was used to analyze the correlation between the CSF2RB and immune cells. Finally, we used Western blot, real-time quantitative PCR (RT-qPCR), and immunohistochemistry (IHC) to validate CSF2RB expression in cancer and para-cancerous tissues. Results: We identified that CSF2RB played an important role in the tumor microenvironment of LUAD. The expression of CSF2RB in tumor tissues was lower than that in normal tissues. Furthermore, the Kaplan–Meier plotter showed that a low CSF2RB expression was associated with poor survival and multivariate COX regression analysis revealed that the CSF2RB gene was an independent risk factor for prognosis, independent of whether patients received chemotherapy or radiotherapy. More importantly, a high expression of CSF2RB was related to early T, N, and clinical stages. GSEA analysis revealed that CSF2RB associated with diverse immune-related pathways, including T-cell receptor signaling pathway, Toll-like receptor signaling pathway, and B-cell receptor signaling pathway. CSF2RB expression levels were also positively related with the levels of infiltrating CD4+ T cells, macrophages, NK cells, and monocytes in LUAD. Finally, tumor tissues from LUAD patients were used for the assessment of CSF2RB expression. It was significantly lower in tumor sites than in adjacent normal tissues, which was consistent with data analysis. Conclusion: CSF2RB effectively predicted the prognosis of patients with lung adenocarcinoma which could also be a potential target for cancer treatment and prevention. However, further studies are required to elucidate the function and regulatory mechanisms of CSF2RB and to develop some novel treatment strategies.

Adenocarcinoma of the esophagogastric junction (AEG) is a fatal disease. Accumulating evidence indicates that, for a comprehensive understanding of AEG, studies should be conducted not only to investigate tumor cells, but also the tumor microenvironment (TME). In this study, we collected AEG patient data from The Cancer Genome Atlas, and used the CIBERSORT algorithm to analyze tumor-infiltrating immune cell profiles. The levels of CD8⁺ T cells and M0 and M2 macrophages were relatively high in AEG tissues. M2 macrophages were abundant in G3 tumors, and neutrophils were associated with poor prognosis. Myeloid-derived suppressor cells (MDSCs) represent a heterogeneous population of immunosuppressive cells which share a similar origin to neutrophils and macrophages. We further analyzed the levels of MDSCs in AEG patients and healthy donors (HD) using flow cytometry. MDSC levels were elevated at tumor sites, with polymorphonuclear MDSCs (PMN-MDSCs) being the predominant subtype. Circulating MDSCs partly represented cells at the tumor site. We observed that PMN-MDSC levels at tumor sites were positively correlated with advanced staging, low grade, lymph node metastasis, and HER2⁻ status. Immunohistochemistry and immunofluorescence analyses indicated that activation of the STAT3 and NF-κB pathways in MDSCs may be a potential mechanism for cancer progression. Our studies provided a comprehensive perspective involving tumor-infiltrating immune cells, and detailed insights into the proportion of MDSCs in AEG and their clinical significance. Together, these findings may improve our current understanding of cancer progression involving tumor-infiltrating immune cells in the TME.

Esophageal carcinoma (EC) is a common malignant tumor of the upper digestive tract worldwide. An analysis of the latest data from cancer centers in China showed that the incidence of EC and the number of deaths due to EC in China in 2015 were 266,000 and 188,000, respectively, ranking sixth (6.3%) and fourth (8.0%) among all malignant tumors. The early diagnosis and treatment of EC and standardized diagnosis and treatment are important tasks for EC healthcare professionals in various centers across the country. At present, the 8th edition of the EC staging system jointly released by Union for International Cancer Control (UICC) and American Joint Committee on Cancer (AJCC) is the most recent, authoritative and widely used EC staging standard. The EC professional committee of the Chinese Anti-Cancer Association also organizes the "EC Standardization Campaign in China" every year to promote the development of EC diagnostic and treatment norms throughout the country. Since 2011, the EC Committee of the Chinese Anti-Cancer Association has published the Guidelines for Standardized Diagnosis and Treatment of EC. Considering the increasing number of EC clinical studies and the continuous progress in diagnostic and treatment technologies in recent years, the updated Guidelines will include the latest progress in the diagnosis and treatment of EC, with a goal of promoting the forward development of EC diagnosis and treatment in clinical practice.

Periodontitis, an infectious disease originating from dental biofilms that causes the irreversible loss of alveolar bone, is accompanied by gradual biofilm formation and the continuous progression of inflammation. A small peptide derived from penetratin, Arg-Gln-Ile-Arg-Arg-Trp-Trp-Gln-Arg-NH₂ (RR9), appears to have antibacterial properties against selected strains associated with periodontitis. The purpose of this research is to assess the antibacterial activity and mechanism of RR9 against the initial oral colonizers Streptococci oralis, Streptococci gordonii, and Streptococci sanguinis and to investigate the cytotoxicity of RR9 on human gingival fibroblasts in vitro. The effects of RR9 on the initial oral settlers of planktonic and biofilm states were evaluated by measuring the MIC, MBC, bactericidal kinetics, and antibiofilm activity. Visual evidence and antibacterial mechanisms were identified, and the anti-inflammatory activity and cytotoxicity were measured. The results demonstrated that RR9 can inhibit the growth of streptococci in the planktonic state and during biofilm formation in vitro while keeping a low toxicity against eukaryotic cells. The antibacterial mechanism was proven to be related to the lower expression of sspA in streptococci. RR9 may be used as a potential antimicrobial and anti-infective agent for periodontal disease.

Synchronous multiple primary esophageal squamous cell carcinoma (S-MPESCC) refers to more than one primary esophageal carcinoma detected in a solitary patient at the time of initial presentation. The purpose of this study was to evaluate the clinicopathological features, appropriate surgical approaches and long-term survival in patients with S-MPESCC by comparing with those with solitary esophageal squamous cell carcinoma (SESCC). In total, 567 patients with esophageal squamous cell carcinoma surgically resected in Tianjin Medical University Cancer Institute and Hospital from January 2012 to December 2018 were screened for retrospective analysis (50 in the S-MPESCC group and 516 in the SESCC group). No significant difference was observed in terms of other characteristics except total alcohol consumption (P = 0.029). S-MPESCC had higher lymph node rate than SESCC (62.0% and 44.1%, respectively; P = 0.015) especially in upper mediastinal (32.0% and 18.6%, respectively; P = 0.023) and abdominal (38.0% and 22.8%, respectively; P = 0.017) regions. The survival was not different between the two groups, and the 5-year survival rates of S-MPESCC and SESCC were 46.2% and 50.8%, respectively (P = 0.507). But for patients with pT3-4 cancers, the survival in S-MPESCC was worse than that in SESCC (P = 0.033). In the multivariate analysis, pT stage of primary cancer was an important independent predictor of prognosis in patients with S-MPESCC (hazard ratio [HR], 3.968; 95% confidence interval [CI], 1.031 to 15.268; P = 0.045). S-MPESCC was significantly different from SESCC in terms of clinicopathological characteristics include alcohol intake and pattern of lymphatic metastasis. Furthermore, S-MPESCC showed worse long-term survival than SESCC with increasing depth of primary cancer infiltration.

Endometrial cancer (EC) is a one of the most prevalent gynecological malignancies worldwide; however, the molecular mechanisms driving its progression remain insufficiently understood. In the present study, DNA polymerase θ (POLQ), which is implicated in multiple types of cancer, was comprehensively investigated in EC using data from The Cancer Genome Atlas and TNMplot datasets, with further validation in an independent patient cohort. POLQ expression was markedly upregulated in EC tissues and was associated with reduced 15‑year overall survival. Increased POLQ levels were also associated with higher Ki67 proliferation indices, distinct patterns of T‑cell infiltration and enhanced programmed death‑ligand 1 (PD‑L1) expression. Gene Set Enrichment Analysis revealed that POLQ expression was associated with pathways involved in cell proliferation, cell cycle regulation and DNA damage repair. Mechanistic studies based on POLQ knockdown in EC cells were conducted in vitro using small interfering RNA‑mediated gene silencing, followed by functional assays including cell proliferation assay, flow cytometric cell cycle analysis, apoptosis assay, migration and invasion assays, and western blot analysis to detect the expression of key proteins involved in ATM/P53 signaling and epithelial‑mesenchymal transition (EMT) regulation. These experiments further demonstrated that POLQ may accelerate EC progression via two complementary mechanisms: i) Activation of ataxia‑telangiectasia mutated/P53 signaling to facilitate cell cycle checkpoint bypass; and ii) induction of EMT via cadherin switching. Collectively, these findings established POLQ as a robust prognostic biomarker and a promising therapeutic target in EC.