CD39/CD73-adenosine pathway has been recently defined as an important tumor-induced immunosuppressive mechanism. We here documented a fraction of CD11bCD33 myeloid-derived suppressor cells (MDSCs) in peripheral blood and tumor tissues from non-small cell lung cancer (NSCLC) patients expressed surface ectonucleotidases CD39 and CD73. Tumor TGF-β stimulated CD39 and CD73 expression, thereby inhibited T cell and NK cell activity, and protected tumor cells from the cytotoxic effect of chemotherapy through ectonucleotidase activity. Mechanistically, TGF-β triggered phosphorylation of mammalian target of rapamycin, and subsequently activated hypoxia-inducible factor-1α (HIF-1α) that induced CD39/CD73 expression on MDSCs. CD39 and CD73 on MDSCs, therefore, link their immunosuppressive and chemo-protective effects to NSCLC progression, providing novel targets for chemo-immunotherapeutic intervention.

Metformin is a broadly prescribed drug for type 2 diabetes that exerts antitumor activity, yet the mechanisms underlying this activity remain unclear. We show here that metformin treatment blocks the suppressive function of myeloid-derived suppressor cells ( SignificanceThe antitumor activity of an anti-diabetes drug is attributable to reduced immunosuppressive activity of myeloid-derived tumor suppressor cells.

Malignant pleural effusion (MPE) is an indication of advanced cancer. Immune dysfunction often occurs in MPE. We aimed to identify the reason for impaired T cell activity in MPE from lung cancer patients and to provide clues toward potential immune therapies for MPE. The surface inhibitory molecules and cytotoxic activity of T cells in MPE and peripheral blood (PB) were analyzed using flow cytometry. Levels of inflammatory cytokines in MPE and PB were tested using ELISA. TGF-β expression in tumor-associated macrophages (TAMs) was also analyzed. The effect of TAMs on T cells was verified in vitro. Lastly, changes in T cells were evaluated following treatment with anti-TGF-β antibody. We found that expression levels of Tim-3, PD-1 and CTLA-4 in T cells from MPE were upregulated compared with those from PB, but levels of IFN-γ and Granzyme B were downregulated (p < 0.05). The amount of TGF-β was significantly higher in MPE than in PB (p < 0.05). TGF-β was mainly produced by TAMs in MPE. When T cells were co-cultured with TAMs, expression levels of Tim-3, PD-1 and CTLA-4 were significantly higher than controls, whereas levels of IFN-γ and Granzyme B were significantly decreased, in a dose-dependent manner (p < 0.05). In vitro treatment with anti-TGF-β antibody restored the impaired T cell cytotoxic activity in MPE. Our results indicate that macrophage-derived TGF-β plays an important role in impaired T cell cytotoxicity. It will therefore be valuable to develop therapeutic strategies against TGF-β pathway for MPE therapy of lung cancer.

BackgroundEnteral nutrition is increasingly advocated in the treatment of acute pancreatitis, but its timing is still controversial. The aim of this meta-analysis was to find out the feasibility of early enteral nutrition within 48 hours of admission and its possible advantages.Methods and FindingsWe searched PubMed, EMBASE Databases, Web of Science, the Cochrane library, and scholar.google.com for all the relevant articles about the effect of enteral nutrition initiated within 48 hours of admission on the clinical outcomes of acute pancreatitis from inception to December 2012. Eleven studies containing 775 patients with acute pancreatitis were analyzed. Results from a pooled analysis of all the studies demonstrated that early enteral nutrition was associated with significant reductions in all the infections as a whole (OR 0.38; 95%CI 0.21–0.68, P<0.05), in catheter-related septic complications (OR 0.26; 95%CI 0.11–0.58, P<0.05), in pancreatic infection (OR 0.49; 95%CI 0.31–0.78, P<0.05), in hyperglycemia (OR 0.24; 95%CI 0.11–0.52, P<0.05), in the length of hospitalization (mean difference −2.18; 95%CI −3.48−(−0.87); P<0.05), and in mortality (OR 0.31; 95%CI 0.14–0.71, P<0.05), but no difference was found in pulmonary complications (P>0.05). The stratified analysis based on the severity of disease revealed that, even in predicted severe or severe acute pancreatitis patients, early enteral nutrition still showed a protective power against all the infection complications as a whole, catheter-related septic complications, pancreatic infection complications, and organ failure that was only reported in the severe attack of the disease (all P<0.05).ConclusionEnteral nutrition within 48 hours of admission is feasible and improves the clinical outcomes in acute pancreatitis as well as in predicted severe or severe acute pancreatitis by reducing complications.

Background Impaired intestinal barrier structure and function have been validated as an important pathogenic process in type 2 diabetes mellitus (T2DM). Gut dysbiosis is thought to be the critical factor in diabetic intestinal pathogenesis. As the most abundant commensal bacteria, Faecalibacterium prausnitzii (F. prausnitzii) play important roles in gut homeostasis. The microbial anti‐inflammatory molecule (MAM), an F. prausnitzii metabolite, has anti‐inflammatory potential in inflammatory bowel disease (IBD). Thus, we aimed to explore the function and mechanism of MAM on the diabetic intestinal epithelium. Methods 16S high‐throughput sequencing was used to analyze the gut microbiota of db/db mice (T2DM mouse model). We transfected a FLAG‐tagged MAM plasmid into human colonic cells to explore the protein‐protein interactions and observe cell monolayer permeability. For in vivo experiments, db/db mice were supplemented with recombinant His‐tagged MAM protein from E. coli BL21 (DE3). Results The abundance of F. prausnitzii was downregulated in the gut microbiota of db/db mice. Immunoprecipitation (IP) and mass spectroscopy (MS) analyses revealed that MAM potentially interacts with proteins in the tight junction pathway, including zona occludens 1 (ZO‐1). FLAG‐tagged MAM plasmid transfection stabilized the cell permeability and increased ZO‐1 expression in NCM460, Caco2, and HT‐29 cells. The db/db mice supplemented with recombinant His‐tagged MAM protein showed restored intestinal barrier function and elevated ZO‐1 expression. Conclusions Our study shows that MAM from F. prausnitzii can restore the intestinal barrier structure and function in DM conditions via the regulation of the tight junction pathway and ZO‐1 expression.

Hepatocellular carcinoma (HCC), the most common primary tumor of the liver, has a poor prognosis and rapid progression. MicroRNAs (miRNAs) play important roles in carcinogenesis and tumor progression. Insulin-like growth factor 1 receptor (IGF1R) is a transmembrane heterotetrameric protein that has been reported to promote transformation to malignancy and cancer cell proliferation and survival. In this study, we found that the expression of miR-29a-3p was downregulated in HCC patients, resulting in poor survival rates. Contrastingly, the overexpression of miR-29a-3p significantly inhibited proliferation and migration in HepG2 cells. miR-29a-3p directly targeted IGF1R and down-regulated its expression. Moreover, knockdown of IGF1R led to the increased production of chemokine ligand 5 (CCL5). In tumor lesions, the local expression of CCL5 negatively affected the expression of IGF1R. Transwell analysis showed that CCL5 was important for the chemotactic movement of CD8+ T lymphocytes. The expression of CCL5 in HCC tissues positively correlated with the expression of CD8+ T lymphocyte surface marker, CD8. Patients with high CCL5 expression exhibited better survival. Our results revealed that miR-29a-3p is a tumor suppressor gene that acts by directly repressing the oncogene IGF1R, which takes part in immunoregulation in tumor microenvironments in HCC, implying that miR-29a-3p could be a potential target for HCC treatment.

Long intergenic noncoding RNAs (lincRNAs) play important roles in regulating the biological functions and underlying molecular mechanisms of colorectal cancer (CRC). Here, we investigated the association of linc-POU3F3 and prognosis in CRC. We demonstrated that linc-POU3F3 was overexpressed in CRC tissues and positively correlated with tumor grade and N stage. Inhibition of linc-POU3F3 resulted in inhibition of cell proliferation and G1 cell cycle arrest, which was mediated by cyclin D1, CDK4, p18, Rb, and phosphorylated Rb. Inhibition of linc-POU3F3 induced apoptosis, and suppressed migration and invasion in LOVO and SW480 cell lines. This inhibition also increased the expressions of epithelial markers and decreased the expressions of mesenchymal markers, thus inhibiting the cancer epithelial-mesenchymal transition. The decreased migration and invasion following linc-POU3F3 knockdown were mediated by an increased BMP signal. Furthermore, autophagy was enhanced by linc-POU3F3 knockdown, suggesting the involvement of autophagy in the induced apoptosis. Collectively, linc-POU3F3 might be crucial in pro-proliferation, anti-apoptosis, and metastasis in LOVO and SW480 cells by regulating the cell cycle, intrinsic apoptosis, BMP signaling and autophagy. Thus, linc-POU3F3 is a potential therapeutic target and novel molecular biomarker for CRC.

BackgroundAlthough the chemopreventive effect of 5-aminosalicylates on patients with ulcerative colitis has been extensively studied, the results remain controversial. This updated review included more recent studies and evaluated the effectiveness of 5-aminosalicylates use on colorectal neoplasia prevention in patients with ulcerative colitis.MethodsUp to July 2013, we searched Medline, Embase, Web of Science, Cochrane CENTRAL, and SinoMed of China for all relevant observational studies (case-control and cohort) about the effect of 5-aminosalicylates on the risk of colorectal neoplasia among patients with ulcerative colitis. The Newcastle-Ottawa Scale was used to assess the quality of studies. Adjusted odds ratios (ORs) were extracted from each study. A random-effects model was used to generate pooled ORs and 95% confidence intervals (95%CI). Publication bias and heterogeneity were assessed.ResultsSeventeen studies containing 1,508 cases of colorectal neoplasia and a total of 20,193 subjects published from 1994 to 2012 were analyzed. 5-aminosalicylates use was associated with a reduced risk of colorectal neoplasia in patients with ulcerative colitis (OR 0.63; 95%CI 0.48–0.84). Pooled OR of a higher average daily dose of 5-aminosalicylates (sulfasalazine ≥ 2.0 g/d, mesalamine ≥ 1.2 g/d) was 0.51 [0.35–0.75]. Pooled OR of 5-aminosalicylates use in patients with extensive ulcerative colitis was 1.00 [0.53–1.89].ConclusionOur pooled results indicated that 5-aminosalicylates use was associated with a reduced risk of colorectal neoplasia in patients with ulcerative colitis, especially in the cases with a higher average daily dose of 5-aminosalicylates use. However, the chemopreventive benefit of 5-aminosalicylates use in patients with extensive ulcerative colitis was limited.