Multimarker miR Blood Assay for Breast Cancer Detection

Institution: John Wayne Cancer Institute
Investigator(s): David Hoon, MSc, Ph.D. -
Award Cycle: 2010 (Cycle 16) Grant #: 16IB-0076 Award: $265,415
Award Type: IDEA
Research Priorities
Detection, Prognosis and Treatment>Innovative Treatment Modalities: search for a cure

Initial Award Abstract (2010)

Current approaches of breast cancer screening by mammograms, ultrasound, and tissue core biopsy are costly and inefficient. Breast cancer detection with a blood assay would be less costly, more efficient, and more logistically practical to routinely screen women in the community. MicroRNAs (miRs) represent a class of naturally occurring small non-coding RNA molecules (18~22 nucleotides). Some miRs are expressed in a tissue-specific manner and are considered to play pivotal functional roles. Studies have demonstrated expression of various miRs in various human cancers, including breast cancer indicating that they may be potential biomarkers. Although circulating nucleic acids (DNA and mRNA) have clinical utility in cancer patients, their assessment of in serum/plasma specimens has been problematic because of nucleic acid instability and degradation which compromise overall assay sensitivity. By contrast, miRs are highly stable in serum and therefore suitable for investigation as ideal serum biomarkers.

Traditional blood protein biomarkers have not been sensitive enough to detect early stage breast cancer. However, isolation of sufficient amounts of small nucleic acids, such as miR, for biomarker evaluation is extremely difficult. We recently developed a direct qRT-PCR (quantitative real-time PCR) assay for investigating circulating miR in order to bypass miR loss during extraction. One specific miR, called miR-21 is up-regulated in human breast cancer tissue. This project will determine if circulating miR-21 and other miRs in serum could be used to detect early-stage breast cancer with greater sensitivity and accuracy than standard screening/detection. Our overall objective is to develop a multi-marker miR biomarker panel.

Our specific aims are:
1. Develop a robust direct serum assay to detect miR breast biomarkers in early-stage breast cancer patients.
2. Assess the utility of multi-marker miR breast biomarkers and compare their efficiency and accuracy in breast cancer detection to that of mammography, ultrasound, and tissue core biopsy.
3. Determine the clinical utility of the multi-marker serum miR breast biomarker assay for detection of disease recurrence in node-negative early-stage breast cancer patients.

The miR assay will require <5 ml of blood. The plan will be to start out by assessing a pathologically annotated set of different stages of primary breast cancer. If successful, we will then compare the multi-marker assay to mammograms, ultrasound and breast tissue core biopsy for breast cancer diagnosis and disease recurrence within 5 yrs.

The success of multi-marker serum miR biomarker could potentially reduce health care costs, improve screening for breast cancer detection, follow-up for recurrence, reduce exposure from radiation of repetitive imaging approaches, and allow for greater screening compliance.

Final Report (2012)

There is a need for efficient and cost effective blood testing to detect and monitor breast cancer (BCa), thus we are developing a panel of microRNA (miR) biomarkers to assess BCa in patient serum. The overall goal was to assess a multi-miR panel, using RT-qPCR-ds, for improved selectivity and sensitivity in BCa detection and monitoring for disease progression. We successfully developed direct serum (ds) assays for three circulating breast miR.

On developing the assays we demonstrated their utility as a panel in early stage BCa. While miR expression and detection in cancer has shown biomarker potential, the differential expression of any one miR when evaluated over time or by phenotype makes it difficult to select the appropriate species without knowing disease status in advance. As of this final report, we have observed three miRNA (miR-21, -210, and -29b) that have demonstrated complementary expression and detection changes with stage of disease in BCa. Together as a multi-miR panel they improve selectivity in detecting disease and sensitivity in the prediction of disease-free survival (DFS), when compared to any individual miR in the case of detection or clinicopathological prognostic indicators, respectively.

Direct serum assay for microRNA-21 concentrations in early and advanced breast cancer.
Periodical:Clinical Chemistry
Index Medicus: Clin Chem
Authors: Asaga S, Kuo C, Nguyen T, Terpenning M, Giuliano AE, Hoon DS
Yr: 2011 Vol: 57 Nbr: 1 Abs: Pg:84-91