Cancer Proteins (cancer + protein)

Distribution by Scientific Domains

Selected Abstracts

LIV-1 Breast Cancer Protein Belongs to New Family of Histidine-Rich Membrane Proteins with Potential to Control Intracellular Zn2+ Homeostasis

IUBMB LIFE, Issue 4 2000
K. M. Taylor
Abstract Investigation of the protein product of the oestrogen-regulated gene LIV-1, implicated in metastatic breast cancer, has revealed 10 protein sequences of unknown function that belong to a new family with potential to control intracellular Zn2+ homeostasis. Sequence alignment highlights the similarity in transmembrane domains and extramembrane charged residues, indicating potential ion-transport ability. This family has a novel highly conserved motif of 66 residues, including a transmembrane domain and a catalytic zinc-binding sequence of zinc metalloproteases, containing conserved (indicated in bold type) proline and glutamine residues, HEXPHEXGD. These proteins contain more plentiful histidine-rich repeats than zinc transporters, suggesting an ability to bind or transport zinc across membranes. I propose that these 11 proteins form a new family with the potential to control intracellular Zn2+ homeostasis. [source]

Assessing the link between BACH1/FANCJ and MLH1 in DNA crosslink repair

Sharon B. Cantor
Abstract FANCJ (also known as BRIP1 or BACH1) is a DNA helicase that was originally identified by its direct interaction with the hereditary breast cancer protein, BRCA1. Similar to BRCA1, FANCJ function is essential for DNA repair and breast cancer suppression. FANCJ is also mutated in the cancer prone syndrome Fanconi anemia, for which patient cells are characterized by extreme sensitivity to agents that generate DNA interstand crosslinks. Unexpectedly, correction of the interstrand crosslink sensitivity of FANCJ-null patient cells did not require the FANCJ/BRCA1 interaction. Instead, FANCJ binding to the mismatch repair protein, MLH1 was required. Given this finding, we address the role of FANCJ and MLH1 in DNA crosslink processing and how their functions could be linked in checkpoint and/or recombination pathways. We speculate that after DNA crosslink processing and repair, the FANCJ/MLH1 interaction is critical for recovery and restart of replication. These ideas are considered and summarized in this review. Environ. Mol. Mutagen., 2010. 2010 Wiley-Liss, Inc. [source]

Quantum dot-based protein micro- and nanoarrays for detection of prostate cancer biomarkers

Anisha Gokarna
Abstract In this article, we demonstrate the fabrication and detection of cancer protein biochips consisting of micro- and nanoarrays whereby pegylated quantum dots (QDs) conjugated to antibodies (Abs) of prostate specific antigens (PSA) were used for the detection of clinical biomarkers such as PSA. BSA which acts as an efficient blocking layer in microarrays, tends to show an interaction with QDs. In view of this fact, we investigated two series of samples which were fabricated in the presence and absence of BSA blocking layer. Variation in the incubation time required for the antigen,antibody interaction to take place, different proteins as controls and the effect of bare QDs on these microarrays, were the three main parameters which were studied in these two series. Samples fabricated in the absence of BSA blocking layer exhibited an extremely high specificity in the detection of cancer proteins and were also marked by negligible nonspecific binding effects of QDs, in stark contrast to the samples fabricated using BSA as a blocking layer. Fabrication of nanoarrays of QD-conjugated PSA Abs having a spot size of nearly 900,nm has also been demonstrated. Thus, we show the potential offered by QDs in in vitro analysis of cancer biomarker imaging. [source]

Targeted detection of prostate cancer proteins in serum using heavy-isotope-labeled-peptide standards and MALDI-TOF/TOF

Yan Li
Abstract Proteins released from cancer tissues to patient sera can potentially be used to achieve sensitive, specific, and early detection of cancer by means of blood tests. In this study, we used a platform that combines glycopeptide capture, heavy-isotope-labeled-peptide standards, and liquid chromatography coupled to tandem mass spectrometry to determine which glycoproteins from prostate cancer can be detected in sera from patients with early-stage prostate cancer. The detection limit for prostate-specific antigen in serum was 3.44,ng/mL; thus, direct identification of low abundance, cancer-specific proteins was achieved using our platform. We showed that prostatic acid phosphatase and membrane metallo-endopeptidase that were detected in sera were preferentially expressed in prostate cancer tissues. Levels of these two proteins were elevated in biopsy-positive patients but not biopsy-negative groups. Therefore, these two proteins are candidate biomarkers for analysis of patient samples with levels of prostate-specific antigen in the diagnostic gray zone. [source]