Metabolic modulation of cytokine-induced brain endothelial adhesion molecule expression.

OBJECTIVE: Cytokines contribute to cerebro-vascular inflammatory and immune responses by inducing ECAMs' expression. Ischemic insults can be separated into aglycemic and hypoxic components. However, whether aglycemia, hypoxia or OGD plays a major role in dysregulating BBB or promotes immune cell infiltration via ECAMs' expression is not clear. We investigated how expression of ICAM-1, VCAM-1, MAdCAM-1, PECAM-1, E- and P-selectin in response to TNF-α, IL-1ß and IFN-γ was altered by aglycemia (A), hypoxia (H) or combined oxygen glucose deprivation (OGD). METHODS: A cell surface enzyme linked immunoabsorbent assay (cell surface ELISA) was used to analyze ECAM expression. RESULTS: We observed that ICAM-1 and PECAM-1 expressions were insensitive to hypoxia, aglycemia or OGD. Conversely, VCAM-1 and E-selectin were increased by hypoxia, but not by aglycemia. MAdCAM-1 and P-selectin were induced by hypoxia, and decreased by aglycemia. Patterns of cytokine-regulated ECAMs' expression were also modified by metabolic conditions. CONCLUSIONS: Our results indicate that patterns of inflammation-associated ECAMs represent cumulative influences from metabolic stressors, as well as cytokine activation. The expression of ECAMs following tissue injury reflects mechanistic interactions between metabolic disturbances, and alterations in tissue cytokines. Normalization of tissue metabolism, as well as cytokine profiles, may provide important targets for therapeutic treatment of inflammation.

Mesenchymal stem cells effectively deliver an oncolytic adenovirus to intracranial glioma.

Gene therapy represents a promising treatment alternative for patients with malignant gliomas. Nevertheless, in the setting of these highly infiltrative tumors, transgene delivery remains a challenge. Indeed, viral vehicles tested in clinical trials often target only those tumor cells that are adjacent to the injection site. In this study, we examined the feasibility of using human mesenchymal stem cells (hMSC) to deliver a replication-competent oncolytic adenovirus (CRAd) in a model of intracranial malignant glioma. To do so, CRAds with a chimeric 5/3 fiber or RGD backbone with or without CXCR4 promoter driving E1A were examined with respect to replication and toxicity in hMSC, human astrocytes, and the human glioma cell line U87MG by quantitative polymerase chain reaction and membrane integrity assay. CRAd delivery by virus-loaded hMSC was then evaluated in vitro and in an in vivo model of mice bearing intracranial U87MG xenografts. Our results show that hMSC are effectively infected by CRAds that use the CXCR4 promoter. CRAd-CXCR4-RGD had the highest replication, followed by CRAd-CXCR4-5/3, in hMSC, with comparable levels of toxicity. In U87MG tumor cells, CRAd-CXCR4-5/3 showed the highest replication and toxicity. Virus-loaded hMSC effectively migrated in vitro and released CRAds that infected U87MG glioma cells. When injected away from the tumor site in vivo, hMSC migrated to the tumor and delivered 46-fold more viral copies than injection of CRAd-CXCR4-5/3 alone. Taken together, these results indicate that hMSC migrate and deliver CRAd to distant glioma cells. This delivery strategy should be explored further, as it could improve the outcome of oncolytic virotherapy for glioma.

Interaction of microsatellite instability and loss of heterozygosity in adenocarcinoma: multiple markers in adenocarcinoma: an introduction to 'Genetic changes in Slovenian patients with gastric adenocarcinoma evaluated in terms of microsatellite DNA'.

Gastric cancer is the second most frequent cause of cancer death worldwide, yet the precise mechanisms underlying the different subtypes of gastric carcinogenesis are poorly understood. Improvements in the diagnosis and prognosis of gastric cancer over classical clinicopathologic findings such as TNM stage, age or macroscopic tumor type, now include novel techniques for superficial endoscopic examination, and new strategies for genetically analyzing biopsied specimens. The development of gastric adenocarcinomas, such as that of many tumor classes, represents the cumulative effects of several different types of mutations, and it is now recognized that both the loss of normal DNA repair, as well as the mutation, loss or inhibition of tumor suppressor genes contribute to the genetic instability leading to cancer. It might be logically anticipated that the combined burden of these two defects would synergize in carcinogenesis, but the extent to which such pathways cooperate in promoting cancer is still not yet well understood. Clearly, an enhanced appreciation of the mechanisms and interactions of these pathways would aid development of diagnosis and treatment options.

Elevated levels of chemokine receptor CXCR4 in HER-2 negative breast cancer specimens predict recurrence.

INTRODUCTION: CXCR4 is a chemokine receptor that has recently been implicated to play a pivotal role in breast cancer growth and metastasis. In animal models, reduction of CXCR4 expression significantly abrogated metastatic disease and prolonged survival. In human breast cancers, CXCR4 overexpression may portend a worse clinical course. Recent data suggest that HER-2 up-regulates CXCR4, but whether this is applicable in the clinical setting is not known. In this study, we evaluated the role of CXCR4 overexpression in breast cancer and determined whether it can serve as a potential marker of tumor recurrence in HER-2 negative tumors. METHODS: One hundred three patients with stages I to III breast cancers and 6 benign breast tissues were prospectively accrued and analyzed. Study homogeneity was maintained by standardized treatment, surveillance, and compliance protocols. CXCR4 levels were detected using Western blots and results were quantified against 1 microg of HeLa cells (positive controls). HER-2 expression was evaluated using the Hercep program, (Dako Corp., Carpinteria, CA) with a positive result defined as > or = 2. CXCR4 expression was defined as low (<6.6-fold) or high (> or = 6.6-fold). Primary endpoints were cancer recurrence and death. Statistical analysis performed included Spearman's correlation, independent samples t-test, Kaplan-Meier survival analysis, and log-rank test. RESULTS: All 103 cancer specimens had CXCR4 overexpression (mean 6.6 +/- 4.7), while none of the 6 benign breast tissues had detectable level of CXCR4. There were 36 HER-2 (+) tumors and 67 HER-2 (-) tumors. There was no statistical significance in mean CXCR4 overexpression between HER-2 (+) [5.6] and HER-2 (-) [6.6] cancers (P = 0.3; independent samples t-test). Recurrences occurred in 18 of 103 patients (17%); 10 occurred in HER-2 (+) tumors, and 8 occurred in HER-2 (-) patients. CXCR4 expression level was not predictive of cancer recurrence (P = 0.80) or overall survival (P = 0.70) in the HER-2 (+) group. However, among HER-2 negative tumors, 7 of 8 recurrences occurred in the high CXCR4 group (P = 0.037). There was no correlation between the degree of CXCR4 overexpression with tumor size (r = 0.13, P = 0.22), nodal status (r = 0.019, P = 0.4), ER/PR status (r = 0.12, P = 0.29), and HER-2 status (r = 0.091, P = 0.36). CONCLUSIONS: CXCR4 overexpression was observed in all 103 breast cancer specimens but was undetectable in benign breast tissues. CXCR4 overexpression does not correlate with tumor size, nodal status, ER/PR status, and HER-2 status. High CXCR4 overexpression had a significant impact on disease-free survival in HER-2 negative breast cancer patients and may help identify a subset of HER-2 negative breast cancers that have a more aggressive biological behavior.