Background: Epidemiology and animal models suggest that dietary monosodium glutamate (MSG) may contribute to the onset of obesity and the metabolic syndrome.Methods: Families (n = 324) from a rural area of Thailand were selected and provided MSG as the sole source for the use in meal preparation for 10 days. Three hundred forty-nine subjects aged 35–55 years completed the study and were evaluated for energy and nutrient intake, physical activity, and tobacco smoking. The prevalence of overweight and obesity (BMI ≥ 25 kg/m²), insulin resistance (HOMA-IR >3), and the metabolic syndrome (ATP III criteria) were evaluated according to the daily MSG intake.Results: The prevalence of the metabolic syndrome was significantly higher in the tertile with the highest MSG intake. Further, every 1 g increase in MSG intake significantly increased the risk of having the metabolic syndrome (odds ratio 1.14, 95% confidence interval-CI- 1.12 - 1.28) or being overweight (odds ratio 1.16, 95% CI 1.04 - 1.29), independent of the total energy intake and the level of physical activity.Conclusion: Higher amounts of individual MSG consumption are associated with the risk of having the metabolic syndrome and being overweight independent of other major determinants.

Oxysterols are oxidation products of cholesterol that are generated by enzymatic reactions mediated by cytochrome P450 family enzymes or by non-enzymatic reactions involving reactive oxygen and nitrogen species. Oxysterols play various regulatory roles in normal cellular processes such as cholesterol homeostasis by acting as intermediates in cholesterol catabolism. Pathological effects of oxysterols have also been described, and various reports have implicated oxysterols in several disease states, including atherosclerosis, neurological disease, and cancer. Numerous studies show that oxysterols are associated with various types of cancer, including cancers of the colon, lung, skin, breast and bile ducts. The molecular mechanisms whereby oxysterols contribute to the initiation and progression of cancer are an area of active investigation. This review focuses on the current state of knowledge regarding the role of oxysterols in carcinogenesis. Mutagenicity of oxysterols has been described in both nuclear and mitochondrial DNA. Certain oxysterols such as cholesterol-epoxide and cholestanetriol have been shown to be mutagenic and genotoxic. Oxysterols possess pro-oxidative and pro-inflammatory properties that can contribute to carcinogenesis. Oxysterols can induce the production of inflammatory cytokines such as interleukin-8 and interleukin-1β. Certain oxysterols are also involved in the induction of cyclo-oxygenase-2 expression. Inflammatory effects can also be mediated through the activation of liver-X-receptor, a nuclear receptor for oxysterols. Thus, several distinct molecular mechanisms have been described showing that oxysterols contribute to the initiation and progression of cancers arising in various organ systems.

(Cancer Sci 2010; 101: 658–665) Myristoylated alanine-rich C kinase substrate (MARCKS), a substrate of protein kinase C (PKC) has been suggested to be implicated in cell adhesion, secretion, and motility through the regulation of the actin cytoskeletal structure. The quantitative real-time–polymerase chain reaction analysis revealed that MARCKS is significantly overexpressed in Opisthorchis viverrini-associated cholangiocarcinoma (CCA) (P = 0.001) in a hamster model, which correlated with the results of mRNA in situ hybridization. An immunohistochemical analysis of 60 CCA patients revealed a significant increase of MARCKS expression. Moreover, the log–rank analysis indicated that CCA patients with a high MARCKS expression have significantly shorter survival times than those with a low MARCKS expression (P = 0.02). This study investigated whether MARCKS overexpression is associated with CCA metastasis. Using a confocal microscopic analysis of CCA cell lines that had been stimulated with the PKC activator, 12-0-tetradecanoyl phorbol-13-acetate (TPA), MARCKS was found to be translocated from the plasma membrane to the perinuclear area. In addition, phosphorylated MARCKS (pMARCKS) became highly concentrated in the perinuclear area. Moreover, an adhesion assay demonstrated that the exogenous overexpression of MARCKS remarkably promoted cell attachment. Interestingly, after TPA stimulation, the CCA cell line-depleted MARCKS showed a decrease in migration and invasion activity. It can be concluded that in non-stimulation, MARCKS promotes cell attachment to the extracellular matrix. After TPA stimulation, PKC phosphorylates MARCKS leading to cell migration or invasion. Taken together, the results of this study reveal a prominent role for MARCKS as one of the key players in the migration of CCA cells and suggest that cycling between MARCKS and pMARCKS can regulate the metastasis of biliary cancer cells.

Quantitative Changes in Tumor-Associated M2 Macrophages Characterize Cholangiocarcinoma and their Association with Metastasis Tumor-associated macrophages;cancer-associated fibroblasts;cholangiocarcinoma;metastasis; The tumor microenvironment (TME) includes numerous non-neoplastic cells such as leukocytes and fibroblasts that surround the neoplasm and influence its growth. Tumor-associated macrophages (TAMs) and cancerassociated fibroblasts (CAFs) are documented as key players in facilitating cancer appearance and progression. Alteration of the macrophage (CD68, CD163) and fibroblast (${\alpha}-SMA$, FSP-1) cells in Opisthorchis viverrini (Ov) -induced cholangiocarcinoma (CCA) was here assessed using liver tissues from an established hamster model and from 43 human cases using immunohistochemistry. We further investigated whether M2-activated TAMs influence CCA cell migration ability by wound healing assay and Western blot analysis. Macrophages and fibroblasts change their phenotypes to M2-TAMs (CD68+, CD163+) and CAFs (${\alpha}-SMA+$, FSP-1+), respectively in the early stages of carcinogenesis. Interestingly, a high density of the M2-TAMs CCA in patients is significantly associated with the presence of extrahepatic metastases (p=0.021). Similarly, CD163+ CCA cells are correlated with metastases (p=0.002), and they may be representative of an epithelial-to-mesenchymal transition (EMT) with increased metastatic activity. We further showed that M2-TAM conditioned medium can induce CCA cell migration as well as increase N-cadherin expression (mesenchymal marker). The present work revealed that significant TME changes occur at an early stage of Ov-induced carcinogenesis and that M2-TAMs are key factors contributing to CCA metastasis, possibly via EMT processes.