Relevance of circulating tumor cells, extracellular nucleic acids, and exosomes in breast cancer.
Early detection of cancer is vital to improved overall survival rates. At present, evidence is accumulating for the clinical value of detecting occult tumor cells in peripheral blood, plasma, and serum specimens from cancer patients. Both molecular and cellular approaches, which differ in sensitivity and specificity, have been used for such means. Circulating tumor cells and extracellular nucleic acids have been detected within blood, plasma, and sera of cancer patients. As the presence of malignant tumors are clinically determined and/or confirmed upon biopsy procurement-which in itself may have detrimental effects in terms of stimulating cancer progression/metastases-minimally invasive methods would be highly advantageous to the diagnosis and prognosis of breast cancer and the subsequent tailoring of targeted treatments for individuals, if reliable panels of biomarkers suitable for such an approach exist. Herein, we review the current advances made in the detection of such circulating tumor cells and nucleic acids, with particular emphasis on extracellular nucleic acids, specifically extracellular mRNAs and discuss their clinical relevance.
Friel
Anne M
AM
School of Pharmacy and Pharmaceutical Sciences & Molecular Therapeutics for Cancer Ireland, Trinity College Dublin, Dublin 2, Ireland.
Corcoran
Claire
C
Crown
John
J
O'Driscoll
Lorraine
L
D000818:Animals; D014408:Biomarkers, Tumor / Q000097:blood*; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism / Q000401:mortality / Q000473:pathology; D055088:Early Detection of Cancer; D055354:Exosomes / Q000378:metabolism*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D005819:Genetic Markers; D006801:Humans; D035683:MicroRNAs / Q000097:blood; D009360:Neoplastic Cells, Circulating / Q000378:metabolism* / Q000473:pathology; D009696:Nucleic Acids / Q000097:blood*; D011237:Predictive Value of Tests; D011379:Prognosis; D012333:RNA, Messenger / Q000097:blood
D014408:Biomarkers, Tumor; D005819:Genetic Markers; D035683:MicroRNAs; D009696:Nucleic Acids; D012333:RNA, Messenger