Mutations of the p53 gene and loss of heterozygosity at chromosome 17p13.1 are associated with increased survivin expression in breast cancer.

Expression of survivin, a member of the inhibitor-of-apoptosis (IAP) family, is elevated in fetal tissues and in various human cancers originating in the breast, lung, prostate, colon, pancreas, and stomach. Since overexpression of the survivin gene has been linked to poor patient survival in several cancers, survivin may be an important prognostic marker. Mechanisms up-regulating survivin gene expression in cancer are poorly understood.

PCD1, a novel gene containing PDZ and LIM domains, is overexpressed in human breast cancer and linked to lymph node metastasis.

Background: Despite surgical removal of the primary tumor of breast cancer in patients with apparently localized disease, relapse at local or distant sites may occur because undetectable micrometastases were present at the time of diagnosis. Identification of molecules associated with breast cancer metastasis suggests possible new treatments. PCD1, a gene encoding a new member of the PDZ and LIM domain-containing protein family, recently was identified.

A novel aspartic protease gene, ALP56, is up-regulated in human breast cancer independently from the cathepsin D gene.

Tumor cell invasion requires expression of degradative enzymes such as plasminogen activator, collagenase, and cathepsins. Cathepsin D, a lysosomal aspartic protease produced constitutively in human breast cancer cell lines, also has mitogenic activity in breast cancer cells. Additionally, high cathepsin D expression is associated with increased risk of metastasis in patients with node-negative breast cancer.

Enhanced expression of the UROC28 gene in human breast cancer: relationship to ERBB2 gene expression.

Background: ERBB2, a highly important oncogene in invasive breast cancer, is not only a prognostic factor but also a predictive marker for response to therapeutic agents. Recently, An et al. (10) identified a novel gene, UROC28, that is also overexpressed in breast cancer.