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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. ©2014 AACR.

PDF file - 738K, ADDITIONAL MATERIALS AND METHODS, FIGURES AND TABLES Fig S1- Immunohistochemical detection of hERG1 protein in GC specimens. Fig S2- hERG1 protein expression in GC primary samples. Figure S3- hERG1b characterization in primary GC. Fig S4- hERG1 protein expression in GC cell lines. Fig S5- hERG1USO protein expression in GC cell lines. Fig S6- Effects of the PI3K/Akt inhibition on VEGF-A secretion in AKG cells under normoxic conditions. Fig S7- Immunohistochemical detection of hERG1 protein in GC specimens. Fig S8- Immunohistochemical detection of hERG1 protein in GC specimens. Fig S9- VEGF-A and hERG1 expression in GC samples. Fig S10. Interaction analyses on OS between hERG1 and other clinical and pathological parameters (Forest Plot). Fig S11- Comparison between herg1a mRNA and hERG1A protein expression in GC samples. Table S1- Antibodies used for IHC experiments described in the main text. Table S2- Primer Sequences. Primers were used for methylation analysis and RQ-PCR. Table S3- Cell lines used in the experiments described in the main text. Table S4- hERG1 expression in AKG cells treated with alpha-hERG1 siRNAs and WAY hERG1 blocker. Table S5- VEGF-A and Kv 1.3 expression in AKG cells treated with alpha-hERG1 siRNAs, WAY hERG1 blocker and alpha-vegf-a siRNA. Table S6- Characteristics of patients excluded and included into the statistical analyses and distributions of clinical and pathological variables after multiple imputation of missing values.

Purpose Gastric cancer (GC) is still a relevant health issue worldwide. The identification of prognostic factors for progression of gastric dysplasia (GD), the main pre-cancerous lesion of the intestinal-type GC, is hence mandatory. Patients and methods A cohort of 83 GD endoscopic samples belonging to Italian subjects was collected. hERG1 expression was evaluated by immunohistochemistry and scored 0-3, depending on the percentage of stained cells. Expression data were analysed in conjunction with clinico-pathological and survival data. Results hERG1 turned out to be expressed in 67.47% (56 out of 83) of the GD samples. hERG1 expression was higher in high-grade GD compared to low-grade GD (29 out of 39, 74.36% vs 27 out of 44, 61.36%), although the statistical significance was not reached (P=0.246). No association emerged between hERG1 expression and clinical features of the patients (age, gender, localization, H. pylori infection, gastritis and intestinal metaplasia). In a subset of cases for which sequential samples of gastric lesions (from GD to Early Gastric Cancer and Advanced Gastric Cancer) were available, hERG1 expression was maintained in all the steps of gastric carcinogenesis from GD onwards. A general trend to increased expression in advanced lesions was observed. hERG1 score had a statistically significant impact on both Progression-Free Survival (P=0.018) and Overall Survival (P=0.031). In particular, patients displaying a high hERG1 score have a shorter survival. Conclusion hERG1 is aberrantly expressed in human GD samples and has an impact on both PFS and OS, hence representing a novel prognostic marker for progression of GD towards GC of the intestinal histotype. Once properly validated, hERG1 detection could be included in the clinical practice, during endoscopic surveillance protocols, for the management of GD at higher risk of progression, as already proposed for Barrett's oesophagus.

Langerhans cells (LCs) from melanoma patients sentinel lymph nodes (SLN) are poor T cell activators mostly due to an immature immunophenotype. However Antigen Presenting Machinery (APM) role is unknown. We investigated HLA-class I APM components (Delta, LMP-7/10, TAP-1, Calnexin, Tapasin, β2-microglobulin and HLA-A,B,C) in LCs from healthy donors skin and melanoma patients SLN. APM component levels were low in immature epidermal LCs and significantly increased after maturation (p < 0.05); their levels were significantly high in SLN LCs (p < 0.01). APM component expression correlated with melanoma Breslow’s thickness and SLN metastases: HLA-A,B,C level was significantly lower in SLN LCs from thick lesions patients compared with those from thin/intermediate lesions (p < 0.05); β2-microglobulin level was significantly higher in positive SLN LCs compared to negative ones (p < 0.05). Functionally, SLN LCs did not phagocytose exogenous antigens. These findings extend LCs knowledge indicating that they are not fully impaired by melanoma, contributing to design new LCs-based therapeutic approaches.

BACKGROUND: There is a need to identify new markers to assess recurrence risk in early-stage colorectal cancer (CRC) patients. We explored the prognostic impact of ether-a-gò-gò-related gene 1 channels and some hypoxia markers, in patients with nonmetastatic (stage I, II, and III) CRC. METHODS: The expression of hERG1, vascular endothelial growth factor A (VEGF-A), glucose transporter 1, carbonic anhydrase IX (CA-IX), epidermal growth factor receptor (EGF-R), and p53 was tested by immunohistochemistry in 135 patients. The median follow-up was 35 months. Clinicopathologic parameters and overall survival were evaluated. RESULTS: hERG1 displayed a statistically significant association with Glut-1, VEGF-A, CA-IX, and EGF-R; p53 with VEGF-A and CA-IX; Glut-1 with the age of the patients; and EGF-R with TNM and mucin content. TNM and CA-IX were prognostic factors at the univariate analysis; TNM, hERG1, and Glut-1, at the multivariate analysis. Risk scores calculated from the final multivariate model allowed to stratify patients into four different risk groups: A) stage I-II, Glut-1 positivity, any hERG1; B) stage I-II, Glut-1 and hERG1 negativity; C) stage I-II, Glut-1 negativity, hERG1 positivity; D) stage III, any Glut-1 and any hERG1. CONCLUSIONS: hERG1 positivity with Glut-1 negativity identifies a patient group with poor prognosis within stage I-II CRC. The possibility that these patients might benefit from adjuvant therapy, independently from the TNM stage, is discussed. IMPACT: More robust prognostic and predictive markers, supplementing standard clinical and pathologic staging, are needed for node-negative patients.

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. ©2014 AACR.

Cutaneous melanoma represents the main cause of death among skin cancers. The thickness of the lesion at diagnosis is one of the most important prognostic indicators for survival, which is good for thin melanomas (≤1 mm) and worsens as thickness increases. Nevertheless, it is not rare to observe disease progression of thin melanomas or, conversely, a good outcome for those melanomas considered to be at high risk, according to the classical prognostic criteria. In the present paper, we analysed for the first time the expression of the hERG1 protein, a potassium channel frequently overexpressed and misexpressed in cancers, in cutaneous melanocytic lesions. The analysis was carried out on archival samples relative to (a) typical melanocytic nevi, (b) atypical melanocytic nevi, (c) thin (1 mm) melanomas from patients who survived at least 10 years after surgery, (d) thick (4 mm) melanomas from patients who died for melanoma and (e) melanoma metastases. Samples were analysed by immunohistochemistry using an hERG1-specific antibody. We showed that primary cutaneous melanomas with a thickness greater than 4 mm as well as metastatic melanoma lesions are characterized by a high level of hERG1 expression. Conversely, thin melanomas and benign melanocytic lesions (e.g. typical and atypical melanocytic nevi) express hERG1 at significantly lower levels. Although still preliminary, the data presented here enable us to consider hERG1 as a novel candidate biomarker for aggressive melanoma.