Role of TAP1 in the identification of immune-hot tumor microenvironment and its prognostic significance for immunotherapeutic efficacy in gastric carcinoma.

Background: Gastric cancer (GC), a multifaceted gastrointestinal malignancy, is the fourth most prevalent contributor to cancer-related fatalities globally. As a member of the ATP-binding cassette (ABC) family, transporter associated with antigen processing 1 (TAP1) is crucial for conveying antigen peptides from the cytoplasm to the lumen of the endoplasmic reticulum and subsequently loading them onto the major histocompatibility complex (MHC) class I molecules. Recent studies have established the biological significance of TAP1 in upholding tumor survival and facilitating immune evasion by remodeling the tumor microenvironment (TME) and orchestrating immune infiltration. The study was conducted to elucidate the association of TAP1 expression with immunological characteristics, and sought to exploit the value of TAP1 as a biomarker reflecting the inflamed TME and immunotherapeutic response. Methods: RNA-sequencing profiles and clinical annotations were obtained from The Cancer Genome Atlas-stomach adenocarcinoma (TCGA-STAD) cohort and Gene Expression Omnibus (GEO) portal. Preprocessing was conducting using the limma package. Weighted gene co-expression network analysis (WGCNA) was used to identify gene modules and TAP1 co-expressed genes (CEGs) based on correlation patterns. Consensus clustering and silhouette analysis determined the optimal number of TAP1-related groups. Gene expression profiles were integrated and classified using the pamr package. The Estimation of STromal and Immune cells in MAlignant Tumors using Expression data (ESTIMATE) algorithm and single-sample gene set enrichment analysis (ssGSEA) were used to evaluate immunological characteristics. Differential expression analysis was conducted using the limma package. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed. Single-cell RNA sequencing (scRNA-seq) datasets were analyzed using the Seurat toolkit to characterize cell types. Results: Within this investigation, no significant differences in TAP1 expression were observed among patients exhibiting various clinicopathological features, indicating that TAP1 expression was not specific to molecular subtypes. Subsequent analysis revealed a positive correlation between TAP1 and diverse immunological traits, encompassing immunomodulators, tumor-infiltrating immune cells, as well as immune checkpoints across multiple datasets. Besides, within a GC immunotherapy cohort, individuals displaying high TAP1 expression demonstrated an increased likelihood of achieving complete remission (CR) post-treatment, suggesting heightened sensitivity to immunotherapy. In the clinical cohort, TAP1 overexpression in GC patients was positively correlated with CD8. Conclusions: TAP1 appears linked to an inflamed TME and serves as a prospective biomarker for discerning immunological attributes and gauging immunotherapeutic responses in GC, particularly in identifying immune-reactive tumors.

Association of tumor differentiation and prognosis in patients with rectal cancer undergoing neoadjuvant chemoradiation therapy.

BACKGROUND AND OBJECTIVE: Neoadjuvant chemoradiation therapy (NCRT) followed by radical resection has been a common practice for patients with locally advanced rectal cancer. This study aimed to analyse the association of tumor differentiation and prognosis in rectal-cancer patients undergoing NCRT. METHODS: Patients with locally advanced, non-mucinous rectal cancer who underwent NCRT followed by radical resection between 2007 and 2017 were identified from an electronic health record system at the Sixth Affiliated Hospital of Sun Yat-sen University (Guangzhou, China). Multivariable logistic regression and multivariate Cox regression were performed to analyse the association of response to NCRT and survival with clinicopathological characteristics of all these patients. RESULTS: We identified 325 patients (241 males and 84 females; mean age, 54.4 ± 11.2 years) who underwent NCRT followed by radical resection, including 26 (8.0%) with poorly-differentiated rectal cancer, 182 (56.0%) with moderately-differentiated cancer and 117 (36.0%) with well differentiated cancer. Propensity score matching analysis and multivariable logistic regression analysis results showed that tumor differentiation was significantly associated with response to NCRT. In the poor differentiation and non-poor differentiation groups, the 3-year overall survival (OS) rates were 74.6 and 93.5%, respectively, whereas the 3-year local recurrence rates were 18.6 and 3.7%, respectively. Multivariable Cox regression analyses revealed that poor differentiation was an independent risk factor for local recurrence and OS. CONCLUSIONS: Among the patients with locally advanced, non-mucinous rectal cancer, the patients with poorly-differentiated cancer who underwent NCRT had a worse response to NCRT and poorer prognosis than those with moderately- and well-differentiated diseases.

Bone marrow-derived CXCR4-overexpressing MSCs display increased homing to intestine and ameliorate colitis-associated tumorigenesis in mice.

BACKGROUND AND OBJECTIVE: Increasing interest has developed in the therapeutic potential of bone marrow-derived mesenchymal stem cells (MSCs) for the treatment of inflammatory bowel disease (IBD) and IBD-induced cancer. However, whether MSCs have the ability to suppress or promote tumor development remains controversial. The stromal cell-derived factor 1 (SDF-1)/C-X-C chemokine receptor type 4 (CXCR4) axis is well known to play a critical role in the homing of MSCs. In this study, we aimed to evaluate the role of CXCR4-overexpressing MSCs on the tumorigenesis of IBD. METHODS: MSCs were transduced with lentiviral vector carrying either CXCR4 or green fluorescent protein (GFP). Chemotaxis and invasion assays were used to detect CXCR4 expression. A mouse model of colitis-associated tumorigenesis was established using azoxymethane and dextran sulfate sodium (DSS). The mice were divided into three groups and then injected with phosphate buffer saline (PBS), MSC-GFP or MSC-CXCR4. RESULTS: Compared with the mice injected with MSC-GFP, the mice injected with MSC-CXCR4 showed relieved weight loss, longer colons, lower tumor numbers and decreased tumor load; expression of pro-inflammatory cytokines decreased, and signal transducer and activator of transcription 3 (STAT3) phosphorylation level in colon tissue was down-regulated. CONCLUSION: CXCR4-overexpressing MSCs exhibited effective anti-tumor function, which may be associated with enhanced homing to inflamed intestinal tissues.

Anti-fibrogenic Potential of Mesenchymal Stromal Cells in Treating Fibrosis in Crohn's Disease.

BACKGROUND: Intestinal fibrosis is a major complication of CD and may result in stricture formation leading to intestinal obstruction. MSCs play multiple roles in active CD and fibrosis-associated diseases. AIMS: This study was designed to investigate the role of MSCs in CD-associated intestinal fibrosis. METHODS: Intestinal fibrosis was induced over 7 weeks of enema with increasing doses of TNBS and assessed by Masson's trichrome staining. Transcriptome sequencing and gene set enrichment analysis were conducted to reveal the transcriptome changes among groups at the mRNA level. Immunofluorescence assays were used to validate the role of EMT in intestinal fibrosis. Quantitative real-time PCR and immunohistochemistry analyses were performed to clarify the association between the anti-fibrogenic properties of MSCs and the immune microenvironment. Western blotting was used to verify the potential signaling pathways. RESULTS: Fibrotic tissue accumulation and inflammatory cell infiltration were detected in the colon tissue after TNBS induction treatment. Prophylactic MSCs treatment inhibited colon shortening, while therapeutic treatment decreased colon weight. Prophylactic treatment with MSCs inhibited the accumulation of fibrotic tissue, the expression of fibrotic proteins and EMT. Therapeutic MSCs treatment reversed the established intestinal fibrosis and reduced EMT. The secretion of the fibrogenic factors IL-1beta, IL-6 and IL-13 was down-regulated after both MSCs treatment approaches, while IL-10, an anti-fibrogenic factor, was up-regulated. Both MSCs therapies inhibited the expression of TGF-beta and the phosphorylation of Smad2 and Smad3 after TNBS induction. CONCLUSION: MSCs exert anti-fibrogenic activity against CD-associated fibrosis by regulating the inflammatory environment, inhibiting the TGF-beta/Smad signaling pathway and ameliorating EMT.

Triple primary malignancies in a patient with colorectal adenocarcinoma: A case report.

INTRODUCTION: While colorectal carcinoma is one of the most commonly diagnosed malignancies, its synchronous occurrence with other primary malignancies is rare. PRESENTATION OF CASE: In this case, we describe the diagnosis and surgical intervention of a 55-year-old male patient who was found to have colonic adenocarcinoma at the hepatic flexure, right renal urothelial carcinoma, and malignant mesothelioma. DISCUSSION: None of the previous studies reported these three distinct types of cancer, even in those patients with Lynch Syndrome. To the best of our knowledge, this is the first report of such case. The etiology and pathogenesis of multiple primary malignancies are complex. Common genetic and environmental risk factors that were found in different cancers might increase the risk of multiple primary malignancies. CONCLUSION: The use of genetic testing and preoperative imaging studies should be considered to be invaluable tools for detecting synchronous malignancies. Practicing physicians should pay more attention to the risk of simultaneous separate primary malignancies.

MicroRNA-30a regulates cell proliferation and tumor growth of colorectal cancer by targeting CD73.

BACKGROUND: MicroRNAs are non-coding RNAs which regulate a variety of cellular functions in the development of tumors. Among the numerous microRNAs, microRNA-30a (miR-30a) is thought to play an important role in the processes of various human tumors. In this study, we aimed to explore the role of miR-30a in the process of colorectal cancer (CRC). METHODS: The quantitative real-time PCR and western blot analysis were used to detect the expressions of miR-30a and CD73 in CRC cell lines and clinical tissues. The luciferase reporter assay was conducted to validate the association between miR-30a and CD73. The CCK-8, terminal deoxynucleotidyl transferase dUTP -biotin nick end labeling (TUNEL) assays and cell cycle flow cytometry were carried out to verify the biological functions of miR-30a in vitro. The nude mouse tumorigenicity experiment was used to clarify the biological role of miR-30a in vivo. RESULTS: The expression of miR-30a was significantly reduced in tumor cells and tissues of CRC. The proliferation ability of CRC cells was suppressed and the apoptosis of cells was promoted when miR-30a is over-regulated, however, the biological effects would be inverse since the miR-30a is down-regulated. CD73 is thought to be a target binding gene of miR-30a because miR-30a can bind directly to the 3'-UTR of CD73 mRNA, subsequently reducing its expression. The proliferation suppression of the CRC cells mediated by miR-30a could be rescued after up-regulating the expression of CD73. CONCLUSIONS: MiR-30a plays an important role on regulating the cell proliferation and apoptosis, thus affecting the growth of the tumor in CRC. And it may participate in the disease process of CRC by regulating the expression of CD73.

Comparison of Adipose-Derived and Bone Marrow Mesenchymal Stromal Cells in a Murine Model of Crohn's Disease.

BACKGROUND: Mesenchymal stromal cells (MSCs) have been used in the treatment of Crohn's disease (CD) because of the immunomodulatory ability. AIM: The aim of this study was to investigate the therapeutic effect of adipose-derived MSCs (AD-MSCs) and to compare the therapeutic effect of AD-MSCs with that of bone marrow MSCs (BM-MSCs) in a murine model of CD. METHODS: Murine colitis model of CD was created by trinitrobenzene sulfonic acid (TNBS). Twelve hours after treatment with TNBS, the mouse model was injected with MSCs intraperitoneally. Real-time polymerase chain reaction and immunohistochemistry staining were used to measure the expression levels of inflammatory cytokines in colonic tissues to investigate the therapeutic effect of AD-MSCs. The ten-day survival was recorded after infusion of MSCs. RESULTS: Intraperitoneal injection of MSCs alleviated the clinical and histopathologic severity of intestinal inflammation, and improved the survival of the TNBS-induced mouse model of CD. AD-MSCs could effectively increase the expression of interleukin-10 and reduce the secretion of pro-inflammatory cytokines including tumor necrosis factor-α, interleukin-12, and vascular endothelial growth factor. The mucosal injury was repaired by AD-MSCs. These effects were comparable between AD-MSCs and BM-MSCs. CONCLUSIONS: The therapeutic effect appears similar between AD-MSCs and BM-MSCs in treating CD. AD-MSCs may be a potential alternative of cell-based therapy for CD.

Laparoscopic Colorectal Resection in Octogenarian Patients: Is it Safe? A Systematic Review and Meta-Analysis.

The population older than 80 years has been increasing. A significant proportion of colorectal diseases that require colorectal resection occur in very elderly patients. However, the benefits of laparoscopy remain controversial in octogenarians. A systematic review and meta-analysis of observational study was performed to compare clinical outcomes between laparoscopic versus open colorectal resection in octogenarians.The PubMed, EMBASE, Ovid, Web of Science, and Cochrane databases from the years 1990 to 2015 were searched for studies that compare surgical outcomes between laparoscopic and open colorectal resection in octogenarians (≥80 years old).Seven eligible studies including 528 laparoscopic and 484 open colorectal resections were identified. Laparoscopic approach was associated with lower rate of mortality (odds ratio [OR] 0.48, P = 0.03), overall complications (OR 0.54, P < 0.001), and prolonged ileus (OR 0.56, P = 0.009), quicker bowel function return (standardized mean difference [SMD] -0.50, P< 0.001), and shorter length of hospital stay (SMD -0.47, P = 0.007). No differences were found in anastomotic leak (OR 1.16, P = 0.72), respiratory complication (OR 0.60, P = 0.07), and reoperation (OR 0.85, P = 0.69).Laparoscopic colorectal resection is as safe as open approach, and the short-term outcomes appear to be more favorable in octogenarians.