The aim of this paper was to determine the clinical significance of the MHC class I chain-related molecule A(MICA) and NKG2D receptor on NK cells in pancreatic cancer. We compared MICA expression in malignant (n = 103), inflammatory (n = 28), and normal (n = 17) pancreatic tissues using immunohistochemistry and assessed serum levels of soluble MICA (sMICA) and NKG2D expression on NK cells in patients with pancreatic cancer (n = 103), in patients with chronic pancreatitis (n = 28), and in healthy volunteers (n = 43). Expression of MICA was detected in 89.3% of pancreatic cancer tissues, whereas fewer were expressed in inflammatory and normal pancreatic tissues. The levels of sMICA were frequently elevated in patients with advanced pancreatic cancer. The elevation of sMICA was associated with down-regulated NKG2D expression and impaired activity of NK cells. The successful tumor resection significantly decreased serum levels of sMICA and increased the NKG2D expression; there was an inverse correlation between change in sMICA levels and that in NKG2D expression. MICA expression, preoperative sMICA levels and NKG2D intensity were found to be independent prognostic factors in resected pancreatic cancer. This study supports the clinical significance of release of MICA for the malignant progression of pancreatic cancer. The successful tumor resection for pancreatic cancer may have a beneficial effect on NKG2D-mediated antitumor immunity. Our results also suggest sMICA and NKG2D expression on NK cells may be useful to identify risk patients at time point of diagnosis.

Pancreatic cancer is characterized by early metastasis and high mortality. In this study, the role of miR-143 in invasion and metastasis was investigated in pancreatic cancer cells. miR-143 expression was established by an adenovirus-carried miR-143 expression cassette. mRNA and protein levels of gene expression were examined by RT-PCR and Western blot assay, respectively. Rho GTPases activity was measured by the pull down assay. The role of miR-143 in migration and invasion of Panc-1 cells was tested in vitro. The antimetastatic effect of miR-143 was tested in a liver metastasis model, while its antitumor growth effect was tested in a xenograft Panc-1 tumor model. Results demonstrated that ARHGEF1 (GEF1), ARHGEF2 (GEF2), and K-RAS genes are the targets of miR-143. miR-143 expression significantly decreased mRNA and protein levels of GEF1, GEF2, and K-RAS genes; lowered the constitutive activities of RhoA, Rac1, and Cdc42 GTPases; decreased the protein levels of MMP-2 and MMP-9; but significantly increased the protein level of E-cadherin. miR-143 expression also significantly inhibited the migration and invasion of Panc-1 cells in vitro, liver metastasis, and xenograft tumor growth in vivo. Our study suggested that miR-143 plays a central role in the invasion and metastasis of pancreatic cancer and miR-143 is a potential target for pancreatic cancer therapy.

T cells play vital roles in the development and progression of acute coronary syndromes (ACS), including cytotoxicity mediated by CD8+ T cells and immunoregulatory activity mediated by CD4+ T cells. Interleukin (IL)‐9‐secreting CD4+ T cells (Th9 cells) were recently found to be involved in the onset of ACS. We investigated regulatory role of Th9 cells to CD8+ T cells in patients with stable angina pectoris, unstable angina pectoris, and acute myocardial infarction (AMI). Circulating Th9 cells percentage, plasma IL‐9 level, and PU.1 mRNA relative level was up‐regulated in AMI patients compared with controls. There was no significant difference of IL‐9‐secreting CD8+ T cells percentage among groups. CD8+ T cells from AMI patients revealed increased cytotoxicity than those from controls, which presented as enhanced cytotolytic activity to target cells, increased interferon‐γ and tumor necrosis factor‐α secretion, elevated perforin and granzyme B production, and reduced programmed death‐1 and cytotoxic T lymphocyte‐associated protein 4. IL‐9 stimulation did not affect proliferation, but promoted CD8+ T‐cell cytotoxicity from both controls and AMI patients. IL‐9‐secreting CD4+ T cells were enriched in CD4+CCR4−CCR6−CXCR3− cells. The enhancement of CD8+ T‐cell cytotoxicity induced by CD4+CCR4−CCR6−CXCR3− cells was dependent on IL‐9 secretion. The present results indicated that up‐regulation of IL‐9‐secreting CD4+ T cells may contribute to pathogenesis of AMI through enhancement of CD8+ T‐cell cytotoxicity.

The potential for tumor occurrence triggered by cancer stem cells (CSCs) has emerged as a significant challenge for human colorectal cancer therapy. However, the underlying mechanism of CSC development remains controversial. Our study provided evidence that the bulk of tumor cells could dedifferentiate to CSCs and reacquire CSC‐like phenotypes if cultured in the presence of extracellular matrix reagents, such as Matrigel and fibrin gels. In these 3D gels, CD133− colorectal cancer cells can regain tumorigenic potential and stem‐like phenotypes. Mechanistically, the 3D extracellular matrix could mediate cytoskeletal F‐actin bundling through biomechanical force associated receptors integrin β1 (ITGB1), contributing to the release of E3 ligase tripartite motif protein 11 (TRIM11) from cytoskeleton and degradation of the glycolytic rate‐limiting enzyme phosphofructokinase (PFK). Consequently, PFK inhibition resulted in enhanced glycolysis and upregulation of hypoxia‐inducible factor 1 (HIF1α), thereby promoting the reprogramming of stem cell transcription factors and facilitating tumor progression in patients. This study provided novel insights into the role of the extracellular matrix in the regulation of CSC dedifferentiation in a cytoskeleton/glycolysis‐dependent manner.