The inflammatory microenvironment has been shown to play important roles in various stages of tumor development including initiation, growth, and metastasis. The inflammasome is a critical innate immune pathway for the production of active IL-1β, a potent inflammatory cytokine. Although inflammasomes are essential for host defense against pathogens and contribute to autoimmune diseases, their role in tumor progression remains controversial. Here, our results demonstrate that the inflammasome and IL-1β pathway promoted tumor growth and metastasis in animal and human breast cancer models. We found that tumor progression was associated with the activation of inflammasome and elevated levels of IL-1β at primary and metastatic sites. Mice deficient for inflammasome components exhibited significantly reduced tumor growth and lung metastasis. Furthermore, inflammasome activation promoted the infiltration of myeloid cells such as myeloid-derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs) into tumor microenvironments. Importantly, blocking IL-1R with IL-1R antagonist (IL-Ra) inhibited tumor growth and metastasis accompanied by decreased myeloid cell accumulation. Our results suggest that targeting the inflammasome/IL-1 pathway in tumor microenvironments may provide a novel approach for the treatment of cancer.

BackgroundsNeutrophil-lymphocyte ratio (NLR) has recently been reported as a predictor of Hepatocellular carcinoma (HCC). However, its prognostic value in HCC still remains controversial. In this study, we aimed to evaluate the association between NLR and clinical outcome of HCC patients by performing meta-analysis.MethodsA comprehensive literature search for relevant studies published up to August 2013 was performed by using PubMed, Ovid, the Cochrane Library and Web of Science databases. Meta-analysis was performed using hazard ratio (HR) or odds ratio (OR) and 95% confidence intervals (95% CIs) as effect measures.ResultsA total of 15 studies encompassing 3094 patients were included in this meta-analysis. Our pooled results showed that high NLR was associated with poor overall survival (OS) and disease free survival (DFS) in HCC initially treated by liver transplantation (HR = 3.42, 95% CI:2.41-4.85,P = 0.000; HR = 5.90, 95% CI:3.99-8.70,P = 0.000, respectively) and surgical resection (HR = 3.33, 95% CI:2.23-4.98, P = 0.000; HR = 2.10, 95% CI: 2.06–2.14, respectively). High NLR was also associated with poor OS in HCC treated by radiofrequency-ablation (HR = 1.28, 95%CI: 1.10-1.48, P = 0.000), TACE (HR = 2.52, 95% CI: 1.64-3.86, P = 0.000) and mixed treatment (HR = 1.85, 95%  CI: 1.40-2.44, P = 0.000), respectively. In addition, high NLR was significantly correlated with the presence of vascular invasion (OR = 2.69, 95% CI: 2.01–3.59, P = 0.000), tumor multifocality (OR = 1.74, 95% CI: 1.30–2.34, P = 0.000) and higher incidence of AFP ≥ 400 ng/ml (OR = 1.46, 95% CI: 1.01–2.09, P = 0.04).ConclusionElevated NLR indicates a poor prognosis for patients with HCC. NLR may be a convenient, easily-obtained, low cost and reliable biomarker with prognostic potential for HCC.

Summary ARID1A, a SWI/SNF chromatin remodeling gene, is commonly mutated in cancer and hypothesized to be tumor suppressive. In some hepatocellular carcinoma patients, ARID1A was highly expressed in primary tumors but not in metastatic lesions, suggesting that ARID1A can be lost after initiation. Mice with liver-specific homozygous or heterozygous Arid1a loss were resistant to tumor initiation while ARID1A overexpression accelerated initiation. In contrast, homozygous or heterozygous Arid1a loss in established tumors accelerated progression and metastasis. Mechanistically, gain of Arid1a function promoted initiation by increasing Cytochrome P450 mediated oxidative stress, while loss of Arid1a within tumors decreased chromatin accessibility and reduced transcription of genes associated with migration, invasion, and metastasis. In summary, ARID1A has context-dependent tumor suppressive and oncogenic roles in cancer.

Elevated platelets based inflammatory indices, especially APRI, was associated with adverse characteristic features and poor prognosis in HCC, especially for patients with HBV infection or cirrhosis. Antiplatelet treatment may represent a potential therapy for HBV-induced HCC recurrence.

Inflammatory bowel diseases (IBD) are characterized for dysregulated intestinal inflammation. Conflicting reports have shown that activation of inflammasome could promote or decrease intestinal inflammation in an acute colitis model, whereas the involvement of inflammasome activation in chronic colitis is poorly understood. In this study, we investigated the role of inflammasome activation in the development of chronic intestinal inflammation by utilizing IL-10 knockout (KO) mouse as an animal model, which develops chronic colitis resembling human IBD. We demonstrate the causative link between inflammasome activation and the development of chronic intestinal inflammation. Our results show that mature IL-1β protein levels were significantly increased in all colon sections from IL-10 deficient mice compared with that of wild type mice. We found that inhibition of inflammasome activities with IL-1 receptor antagonist or caspase 1 inhibitors suppressed IL-1β and IL-17 production from inflamed colon explants. Furthermore, blocking inflammasome activation with caspase-1 inhibitor in vivo significantly ameliorated the spontaneous colitis in IL-10 KO mice. Together, these observations demonstrate that inflammasome activation promotes the development of chronic intestinal inflammation.