Helicobacter pylori infection is characterized by an inflammatory infiltrate, consisting mainly of neutrophils and T cells. This study was undertaken to evaluate the type of gastric T cell response elicited by the secreted peptidyl prolyl cis, trans-isomerase of H. pylori (HP0175) in patients with distal gastric adenocarcinoma. The cytokine profile and the effector functions of gastric tumor-infiltrating lymphocytes (TILs) specific for HP0175 was investigated in 20 patients with distal gastric adenocarcinoma and H. pylori infection. The helper function of HP0175-specific TILs for monocyte MMP-2, MMP-9, and VEGF production was also investigated. TILs cells from H. pylori infected patients with distal gastric adenocarcinoma produced Interleukin (IL)-17 and IL-21 in response to HP0175. HP0175-specific TILs showed poor cytolytic activity while expressing helper activity for monocyte MMP-2, MMP-9 and VEGF production. These findings indicate that HP0175 is able to drive gastric Th17 response. Thus, HP0175, by promoting pro-inflammatory low cytotoxic TIL response, matrix degradation and pro-angiogenic pathways, may provide a link between H. pylori and gastric cancer.

Pancreatic cancer (PC) is an aggressive disease with dismal prognosis. Surgical resection is the recommended treatment for long-term survival, but patients with resectable PC are in the minority (with a 5-year survival rate of 20 %). Therefore, development of novel therapeutic strategies, such as anti-PC immunotherapy, is crucial. α-Enolase (ENO1) is an enzyme expressed on the surface of pancreatic cancer cells and is able to promote cell migration and cancer metastasis. The capacity of ENO1 to induce an immune response in PC patients renders it a true tumor-associated antigen. In this study, we characterized the effector functions of ENO1-specific T cells isolated from PC patients, and we specifically evaluated the successful role of intra-tumoral T helper 17 (Th17) cells and the inhibitory role of regulatory T (Tregs) cells in respectively promoting or reducing the cancer-specific immune response. In this ex vivo study, we have demonstrated, for the first time, that ENO1-specific Th17 cells have a specific anti-cancer effector function in PC patients, and that there are decreased levels of these cells in cancer compared to healthy mucosa. Conversely, there are elevated levels of ENO1-specific Tregs in PC patients which lead to inhibition of the antigen-specific effector T cells, thus highlighting a possible role in promoting PC progression. These results may be relevant for the design of novel immunotherapeutic strategies in pancreatic cancer.

Background:hERG1 channels are aberrantly expressed in human cancers. The expression, functional role and clinical significance of hERG1 channels in pancreatic ductal adenocarcinoma (PDAC) is lacking.Methods:hERG1 expression was tested in PDAC primary samples assembled as tissue microarray by immunohistochemistry using an anti-hERG1 monoclonal antibody (α-hERG1-MoAb). The functional role of hERG1 was studied in PDAC cell lines and primary cultures. ERG1 expression during PDAC progression was studied in Pdx-1-Cre,LSL-KrasG12D/+,LSL-Trp53R175H/+ transgenic (KPC) mice. ERG1 expression in vivo was determined by optical imaging using Alexa-680-labelled α-hERG1-MoAb.Results:(i) hERG1 was expressed at high levels in 59% of primary PDAC; (ii) hERG1 blockade decreased PDAC cell growth and migration; (iii) hERG1 was physically and functionally linked to the Epidermal Growth Factor-Receptor pathway; (iv) in transgenic mice, ERG1 was expressed in PanIN lesions, reaching high expression levels in PDAC; (v) PDAC patients whose primary tumour showed high hERG1 expression had a worse prognosis; (vi) the α-hERG1-MoAb could detect PDAC in vivo.Conclusions:hERG1 regulates PDAC malignancy and its expression, once validated in a larger cohort also comprising of late-stage, non-surgically resected cases, may be exploited for diagnostic and prognostic purposes in PDAC either ex vivo or in vivo.

Purpose: hERG1 channels are aberrantly expressed in several types of human cancers, where they affect different aspects of cancer cell behavior. A thorough analysis of the functional role and clinical significance of hERG1 channels in gastric cancer is still lacking.Experimental Design: hERG1 expression was tested in a wide (508 samples) Italian cohort of surgically resected patients with gastric cancer, by immunohistochemistry and real-time quantitative PCR. The functional link between hERG1 and the VEGF-A was studied in different gastric cancer cell lines. The effects of hERG1 and VEGF-A inhibition were evaluated in vivo in xenograft mouse models.Results: hERG1 was positive in 69% of the patients and positivity correlated with Lauren's intestinal type, fundus localization of the tumor, G1-G2 grading, I and II tumor-node-metastasis stage, and VEGF-A expression. hERG1 activity modulated VEGF-A secretion, through an AKT-dependent regulation of the transcriptional activity of the hypoxia inducible factor. Treatment of immunodeficient mice xenografted with human gastric cancer cells, with a combination of hERG1 blockers and anti-VEGF-A antibodies, impaired tumor growth more than single-drug treatments.Conclusion: Our results show that hERG1 (i) is aberrantly expressed in human gastric cancer since its early stages; (ii) drives an intracellular pathway leading to VEGF-A secretion; (iii) can be exploited to identify a gastric cancer patients' group where a combined treatment with antiangiogenic drugs and noncardiotoxic hERG1 inhibitors could be proposed. Clin Cancer Res; 20(6); 1502-12. Ó2014 AACR.