No abstract

In the present study, we investigated the potential activity of OSI-027, a potent and selective mammalian target of rapamycin (mTOR) complex 1/2 (mTORC1/2) dual inhibitor, against pancreatic cancer cells both in vitro and in vivo. We demonstrated that OSI-027 inhibited survival and growth of both primary and transformed (PANC-1 and MIA PaCa-2 lines) human pancreatic cancer cells. Meanwhile, OSI-027 induced caspase-dependent apoptotic death of the pancreatic cancer cells. On the other hand, caspase inhibitors alleviated cytotoxicity by OSI-027. At the molecular level, OSI-027 treatment blocked mTORC1 and mTORC2 activation simultaneously, without affecting ERK-mitogen-activated protein kinase activation. Importantly, OSI-027 activated cytoprotective autophagy in the above cancer cells. Whereas pharmacological blockage of autophagy or siRNA knockdown of Beclin-1 significantly enhanced the OSI-027-induced activity against pancreatic cancer cells. Specifically, a relatively low dose of OSI-027 sensitized gemcitabine-induced pancreatic cancer cell death in vitro. Further, administration of OSI-027 or together with gemcitabine dramatically inhibited PANC-1 xenograft growth in severe combined immunodeficiency mice, leading to significant mice survival improvement. In summary, the preclinical results of this study suggest that targeting mTORC1/2 synchronously by OSI-027 could be further investigated as a valuable treatment for pancreatic cancer.

Sepsis, a clinical syndrome occurring in patients following infection or injury, is a leading cause of morbidity and mortality worldwide. CD86 (B7-2) is a costimulatory molecule on antigen-presenting cells and plays critical roles in immune responses. In the current study, we investigated the association of two CD86 polymorphisms, rs1129055G/A and rs17281995G/C, with susceptibility to pneumonia-induced sepsis and examined the effects of these two polymorphisms on gene expression in monocytes. CD86 rs1129055G/A and rs17281995G/C were identified in 192 pneumonia-induced septic patients and 201 healthy controls. Data showed that frequencies of the rs1129055GA and AA genotypes were significantly lower in patients than in controls (odds ratio [OR]=0.57, 95 % confidence interval [CI], 0.35-0.93, p=0.023, and OR=0.40, 95 % CI, 0.23-0.71, p=0.002). Interestingly, the other polymorphism, rs17281995G/C, revealed significantly increased numbers in pneumonia-induced sepsis compared to controls (OR=1.85, 95 % CI, 1.07-3.20, p=0.025). Further analyses about CD86 gene expression revealed that both messenger RNA (mRNA) and protein levels of CD86 were downregulated in monocytes from controls carrying rs17281995GC genotype than those carrying wild-type rs17281995GG genotype (p=0.022 and p=0013). These results suggest that polymorphisms in CD86 gene have diverse effects on the pathogenesis of pneumonia-induced sepsis, in which rs17281995G/C may increase the risk of the disease by interfering gene expression of CD86 in monocytes.

Background: Acute lung injury (ALI) is characterized by rapid induction of inflammation at the alveolar-capillary membrane, and immunosuppressive mechanisms were shown to contribute to its resolution. Despite the central role of lymphocytes in initiating and mediating an inflammatory response, their influx dynamics in ALI has not been examined. Methods: We collected mini-BAL samples from the lung of ALI patients over a maximum period of 7 days, and examined the lymphocyte composition. Results: CD3⁺CD4⁺IFN-gamma⁺ Th1 cells were detected early on in all patients examined, while IL-10-producing B cells and CD3⁺CD4⁺CD25^hiFoxp3⁺ Treg cells appeared later. Interestingly, IL-10-producing B cells appeared earlier than Tregs in most subjects, which possibly exerted anti-inflammatory function before Tregs. We then found that in patients with earlier recruitment of IL-10-producing B cells, the magnitude of Th1 inflammation decreased significantly over time, which was not observed in patients with later recruitment of IL-10-producing B cells. Furthermore, early IL-10-producing B cell recruiters also had significantly earlier recruitment of Tregs and better survival than late IL-10-producing B cell recruiters. Conclusion: This study provided data on the alveolar infiltration of lymphocytes during ALI, which suggested an inhibitory role of IL-10-producing B cells in ALI and emphasized the importance of controlling inflammation during the initial stage of ALI.

CD8 T cells are considered to be critical in tumor surveillance and elimination. Increased CD8 T cell frequency and function is associated with better prognosis in cancer patients. Interleukin 10 is a cytokine with controversial roles in CD8 T cell-mediated anti-tumor immunity. We therefore examined the interleukin 10 expression and consumption in CD8 T cells harvested from the peripheral blood and resected tumors of gastric cancer patients of stages II-IV. We found that the gastric cancer patients presented significantly elevated frequencies of interleukin 10-expressing cells in both CD4 and CD8 T cells compared to healthy controls. But distinctive from the interleukin 10-expressing CD4 T cells, which increased in frequency in advanced cancer, the interleukin 10-expressing CD8 T cells did not increase with cancer stage in the peripheral blood and actually decreased with cancer stage in resected tumor. Interleukin 10 and interleukin 10 receptor expression was also enriched in interferon gamma-expressing activated CD8 T cells. Compared to interleukin 10-nonexpressing CD8 T cells, interleukin 10 receptor-expressing CD8 T cells secreted significantly elevated interferon gamma levels. Treatment of anti-CD3/CD28-stimulated, purified CD8 T cells with interleukin 10 alone could significantly enhance CD8 T cell survival, an effect dependent on interleukin 10 receptor expression. Interleukin 10 also increased CD8 T cell proliferation synergistically with interferon gamma but not alone. Analysis of downstream signal transducer and activator of transcription molecules showed that interleukin 10 treatment significantly increased the phosphorylation of signal transducer and activator of transcription 3 and signal transducer and activator of transcription 1 to lesser extent. Together, these results demonstrate that interleukin 10 possessed stimulatory roles in activated CD8 T cells from gastric cancer patients.