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Purpose: Non^small cell lung carcinoma (NSCLC) is one of most common malignant diseases and usually is resistant against apoptosis-inducing chemotherapy. This study is to explore the antiapoptotic mechanisms of interleukin (IL)-22 in human lung cancer. Experimental Design: Nineteen cases with stage I to III NSCLC were collected to determine the expression of IL-22. Stable transfection of human IL-22 cDNA into A549 and PG cells and transfection of IL-22-RNA interference (RNAi) into these cancer cell lines were done to reveal the molecular mechanisms of IL-22. Results: It was found that IL-22 was highly expressed in primary tumor tissue, malignant pleural effusion, and serum of patients with NSCLC. IL-22R1 mRNA was also detected in lung cancer tissues as well as lung cancer cell lines. Overexpression of IL-22 protected lung cancer cell lines from serum starvation-induced and chemotherapeutic drug-induced apoptosis via activation of STAT3 and its downstream antiapoptotic proteins such as Bcl-2 and Bcl-xL and inactivation of extracellular signal-regulated kinase 1/2. Exposure to blocking antibodies against IL-22R1 or transfection with the IL-22-RNAi plasmid in vitro resulted in apoptosis of these lung cancer cells via STAT3 and extracellular signal-regulated kinase 1/2 pathways. Furthermore, an in vivo xenograft study showed that administration of IL-22-RNAi plasmids significantly inhibited the human tumor cell growth in BALB/c nude mice. Conclusions: Our study indicates that autocrine production of IL-22 contributes to human lung cancer cell survival and resistance to chemotherapy through the up-regulation of antiapoptotic proteins.

Background & Aims-T-cell-mediated hepatitis is a leading cause of acute liver failure; there is no effective treatment and the mechanisms underlying its pathogenesis are obscure. The aim of this study was to investigate the immune-cell signaling pathways involved-specifically the role of signal transducer and activator of transcription 3 (STAT3)-in T-cell-mediated hepatitis in mice.

The aim of this study was to determine the safety and potential efficacy of B-cell depletion with the anti-CD20 monoclonal antibody rituximab in patients with primary biliary cirrhosis (PBC) and an incomplete response to ursodeoxycholic acid (UDCA). This open-label study enrolled six patients with PBC and incomplete responses to UDCA to be treated with 2 doses of 1000 mg rituximab separated by 2 weeks and followed for 52 weeks. The primary endpoints were safety and changes in B-cell function. Two patients received only 1 dose of rituximab, one due to activation of latent varicella and the other due to a viral upper respiratory infection. Serum levels of total IgG, IgM, and IgA as well as anti-mitochondrial autoantibodies (AMAs) IgA and IgM decreased significantly from baseline by 16 weeks and returned to baseline levels by 36 weeks. Stimulation of B cells with CpG produced significantly less IgM at 52 weeks after treatment compared with B cells at baseline. In addition, transient decreases in memory B-cell and T-cell frequencies and an increase in CD25 high CD4 1 T cells were observed after treatment. These changes were associated with significant increases in mRNA levels of FoxP3 and transforming growth factor-b (TGF-b) and a decrease in tumor necrosis factor-a (TNF-a) in CD4 1 T cells. Notably, serum alkaline phosphatase levels were significantly reduced up to 36 weeks following rituximab treatment. Conclusion: These data suggest that depletion of B cells influences the induction, maintenance, and activation of both B and T cells and provides a potential mechanism for treatment of patients with PBC with an incomplete response to UDCA. (HEPATOLOGY 2012;55:512-521)