Oncogenic role of JC virus in lung cancer.

The JC virus (JCV) infects a large proportion of the population world wide and can cause progressive multifocal leucoencephalopathy in the context of immunodeficiency. Recent reports provide evidence that it may also be oncogenic. Here, JCV was examined by targeting its T-antigen in lung carcinomas (n=103) and normal lung tissues (n=18) by nested-PCR followed by Southern blot, real-time PCR, immunohistochemistry, in situ hybridization and in situ PCR. Additionally, expression of Ki-67, caspase-3, beta-catenin, p53, and Rb was analysed by immunohistochemistry on tissue microarrays of lung carcinomas. Copy numbers of JCV were compared with clinicopathological features. Normal lung tissue was positive significantly less frequently, and contained a lower copy number of JCV than lung carcinomas (p<0.05), and copies were lower in lung adenocarcinomas than in squamous, small or large cell carcinomas (p<0.05). In situ PCR and immunolabelling revealed JCV positivity in the nuclei of lung carcinoma cells. The JCV copy number correlated closely with sex, and expression of Ki-67 and membrane beta-catenin (p<0.05), but not with age, tumour size, pleural invasion, lymph node metastasis, expression of caspase-3, cytoplasmic beta-catenin, p53 or Rb, prognosis, smoking or cancer family history (p>0.05). Age and UICC staging were independent prognostic factors for lung carcinoma patients. These data suggest that JCV may be involved in lung carcinogenesis, especially in tumour types other than adenocarcinoma. Lung carcinomas with higher JCV copy numbers display high proliferation and down-regulation of cell adhesion mediated by membrane beta-catenin.

Disrupted galectin-3 causes non-alcoholic fatty liver disease in male mice.

Galectin-3, a beta-galactoside-binding animal lectin, is a multifunctional protein. Previous studies have suggested that galectin-3 may play an important role in inflammatory responses. Non-alcoholic fatty liver disease (NAFLD) is increasingly recognized as a liver condition that may progress to end-stage liver disease and based on the known functions of galectin-3, it was hypothesized that galectin-3 might play a role in the development of NAFLD. Thus, this study investigated the role of galectin-3 in NAFLD by comparing galectin-3 knockout (gal3(-/-)) mice and wild-type (gal3(+/+)) mice. The livers of gal3(-/-) male mice at 6 months of age histologically displayed mild to severe fatty change. The liver weight per body weight ratio, serum alanine aminotransferase levels, liver triglyceride levels, and liver lipid peroxide in gal3(-/-) mice were significantly increased compared with those in gal3(+/+) mice. Furthermore, the hepatic protein levels of advanced glycation end-products (AGE), receptor for AGE (RAGE), and peroxisome proliferator-activated receptor gamma (PPARgamma) were increased in gal3(-/-) mice relative to gal3(+/+) mice. In conclusion, this study suggests that the absence of gal3 can cause clinico-pathological features in male mice similar to those of NAFLD.