The Eag potassium channel as a new prognostic marker in ovarian cancer.

Background: Ovarian cancer is the second most common cancer of the female genital tract in the United Kingdom (UK), accounting for 6% of female deaths due to cancer. This cancer is associated with poor survival and there is a need for new treatments in addition to existing chemotherapy to improve survival. Potassium (K+) channels have been shown to be overexpressed in various cancers where they appear to play a role in cell proliferation and progression.

Microcell-mediated chromosome transfer identifies EPB41L3 as a functional suppressor of epithelial ovarian cancers.

We used a functional complementation approach to identify tumor-suppressor genes and putative therapeutic targets for ovarian cancer. Microcell-mediated transfer of chromosome 18 in the ovarian cancer cell line TOV21G induced in vitro and in vivo neoplastic suppression. Gene expression microarray profiling in TOV21G(+18) hybrids identified 14 candidate genes on chromosome 18 that were significantly overexpressed and therefore associated with neoplastic suppression.

Contrasting properties of hypoxia-inducible factor 1 (HIF-1) and HIF-2 in von Hippel-Lindau-associated renal cell carcinoma.

Defective function of the von Hippel-Lindau (VHL) tumor suppressor ablates proteolytic regulation of hypoxia-inducible factor alpha subunits (HIF-1alpha and HIF-2alpha), leading to constitutive activation of hypoxia pathways in renal cell carcinoma (RCC). Here we report a comparative analysis of the functions of HIF-1alpha and HIF-2alpha in RCC and non-RCC cells. We demonstrate common patterns of HIF-alpha isoform transcriptional selectivity in VHL-defective RCC that show consistent and striking differences from patterns in other cell types.

BRCA1 and BRCA2 as ovarian cancer susceptibility genes.

Individuals carrying germline mutations in one allele of the BRCA1 or BRCA2 genes are at significantly increased risk of developing cancer. Although the increased risk of breast cancer is often highlighted, cancer at several other sites is also considerably more common in these individuals. Here, we discuss existing knowledge of the role of BRCA1 and BRCA2 mutation in pre-disposition to ovarian cancer.

BNIP3 expression is linked with hypoxia-regulated protein expression and with poor prognosis in non-small cell lung cancer.

BNIP3 is a proapoptotic protein regulated by hypoxia-inducible factor 1. We analyzed BNIP3 expression in 105 tumor samples from early operable, non-small lung cancer and the relationship of expression to hypoxia-inducible factor 1alpha, other hypoxia-regulated pathways, and prognosis. There was strong cytoplasmic expression in >10% of cells in 40 of 105 cases.

Expression of the cell death genes BNip3 and NIX in ductal carcinoma in situ of the breast; correlation of BNip3 levels with necrosis and grade.

Ductal carcinoma in situ (DCIS) of the breast is an early, non-invasive lesion and the prognosis is associated with the extent of necrosis and cell death within the tumour. Two cell death genes, BNip3 and NIX, are up-regulated in response to hypoxia in breast carcinoma cells, although any involvement of either gene in disease progression is currently unknown. This study has analysed the expression of BNip3 and NIX in 56 samples of breast DCIS, as well as in adjacent benign and invasive breast tissue.

Predominant role of hypoxia-inducible transcription factor (Hif)-1alpha versus Hif-2alpha in regulation of the transcriptional response to hypoxia.

Tumor hypoxia induces the up-regulation of a gene program associated with angiogenesis, glycolysis, adaptation to pH, and apoptosis via the hypoxia-inducible transcription factors (Hifs) 1 and 2. Disruption of this pathway has been proposed as a cancer therapy. Here, we use short interfering RNAs to compare specific inactivation of Hif-1alpha or Hif-2alpha and show markedly different cell type-specific effects on gene expression and cell migration.

A mycobacterial iron chelator, desferri-exochelin, induces hypoxia-inducible factors 1 and 2, NIP3, and vascular endothelial growth factor in cancer cell lines.

Hypoxia is a key phenomenon in tumor behavior, selecting for resistance to apoptosis, conferring resistance to radiotherapy and chemotherapy, and also inducing angiogenic factors such as vascular endothelial growth factor (VEGF). Exochelins are naturally evolved iron chelators produced by Mycobacterium tuberculosis. Because iron chelation has been reported to activate the hypoxia-inducible factor (HIF), we investigated the effects of an exochelin [desferri-exochelin (DFE) 772SM] on this hypoxia-inducible pathway and downstream target genes.

HIF activation identifies early lesions in VHL kidneys: evidence for site-specific tumor suppressor function in the nephron.

Mutations in the von Hippel-Lindau (VHL) gene are associated with hereditary and sporadic clear cell renal carcinoma. VHL acts in a ubiquitin ligase complex regulating hypoxia-inducible factor-1 (HIF-1), but the link between this function and cancer development is unclear. Here we show that in the kidneys of patients with VHL disease, HIF activation is an early event occurring in morphologically normal single cells within the renal tubules.