Navigation Links
Researchers identify need to sample multiple tumor zones in breast cancer
Date:6/14/2012

Philadelphia, PA, June 15, 2012 Certain short strands of RNA, known as microRNAs (miRNAs), have been linked to the progression and metastasis of breast cancer and may provide information about prognosis. However, studies of miRNA expression profiles often report conflicting findings. While the potential for using miRNAs in breast cancer diagnosis is promising, scientists report in a new study published online today in The Journal of Molecular Diagnostics that differences in the amount and types of miRNA within breast tumors can be misleading.

"Personalized medicine will be the future of cancer care," explains lead investigator Stefanie Avril, MD, of the Technical University of Munich. "However, taking a single tumor biopsy for defining individual treatment is probably oversimplified, and we need to take into account the heterogeneity of tumors. "We found considerable differences in the expression of miRNAs associated with breast cancer within a single tumor (referred to as intratumoral heterogeneity). The use of miRNA for diagnosis or prognosis requires sampling at several different tumor locations and of several tumor-involved lymph nodes."

Researchers collected 132 tumor samples from 16 patients who underwent either lumpectomy or mastectomy for large primary invasive breast cancer. Samples were taken from defined tumor zones: the center of the tumor, the periphery, and the area between. Samples were also taken from lymph nodes, if metastases were present. The expression of four miRNAs (miR-31, miR-335, miR-10b, and miR-210) and four control genes (let-7a, miR-16, RNU48, and RNU44) was assessed.

The researchers found significant variation in miRNA expression, from samples both within primary breast cancers and within lymph node metastases from the same patient. The extent of heterogeneity was very similar within the defined tumor zones and between different zones.

To illustrate why intratumoral heterogeneity may produce misleading results if only a single sample is used, the researchers assessed the variation of miRNA expression between different patients. The mean expression of miR31, which is associated with cancer metastasis, from all zones of the primary tumor site in patient 5 was significantly lower than the mean expression from all zones of the primary tumor site of patient 6. However, a sample from a single tumor zone from patient 5 showed a higher expression level than the lowest case from patient 6. "This might in part explain conflicting previous findings regarding miRNA expression profiles," Dr. Avril notes.

"An important strength of this study is the systematic and predefined prospective sampling of tumors in 8 to 10 different areas, whereas previous studies have commonly only analyzed different areas of one tumor section, or core biopsies of the same tumor," says Dr. Avril. "Reliable assessment of breast cancer miRNA profiles should include sampling of the primary tumor in several locations or sampling several tumor-involved lymph nodes when deriving miRNA expression profiles from metastases."


'/>"/>

Contact: David Sampson
jmdmedia@elsevier.com
215-239-3171
Elsevier Health Sciences
Source:Eurekalert

Related biology news :

1. London researchers discover novel mechanism involved in key immune response
2. NTU researchers study little mighty creature for scientific breakthrough
3. UTMB researchers create powerful new method to analyze genetic data
4. Researchers at GW receive federal funds to study the effect earthquakes have on nuclear reactors
5. Stanford researchers help predict the oceans of the future with a mini-lab
6. Researchers complete the first epigenome in Europe
7. UC Santa Barbara researchers develop synthetic platelets
8. Researchers say tart cherries have the highest anti-inflammatory content of any food
9. CSHL researchers solve structure of human protein critical for silencing genes
10. Researchers identify genetic markers to predict male fertility
11. University of Hawaii Cancer Center researchers create new anti-cancer drug
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/11/2017)... -- Research and Markets has announced the addition of ... offering. ... market to grow at a CAGR of 30.37% during the period ... has been prepared based on an in-depth market analysis with inputs ... growth prospects over the coming years. The report also includes a ...
(Date:4/6/2017)... April 6, 2017 Forecasts by ... Document Readers, by End-Use (Transportation & Logistics, Government & ... Gas & Fossil Generation Facility, Nuclear Power), Industrial, Retail, ... Are you looking for a definitive report ... ...
(Date:4/5/2017)... KEY FINDINGS The global market for stem ... 25.76% during the forecast period of 2017-2025. The rise ... growth of the stem cell market. Download ... The global stem cell market is segmented on the ... cell market of the product is segmented into adult ...
Breaking Biology News(10 mins):
(Date:8/15/2017)... ... ... Kapstone Medical is proud to announce that it has reached ... inventors develop and safeguard their latest innovations. The company has grown from a ... clients in the United States and around the world. , Company Founder and ...
(Date:8/15/2017)... NY (PRWEB) , ... August 15, 2017 , ... ... first time on Immuno-Oncology 360° (IO360°) programming through a series of upcoming panels and ... held February 7-9, 2018, at The Roosevelt Hotel in New York City. , “With ...
(Date:8/14/2017)... York, NY (PRWEB) , ... August 14, 2017 , ... ... in Clinical Trials event, which will take place on September 6, 2017 at ... Daniel Karlin, MD , Head of Experimental Medicine, Informatics, and Regulatory Strategy, Pfizer Innovative ...
(Date:8/10/2017)... ... August 09, 2017 , ... As a full-service ... its ideal customers with the right message. Their effective, cutting-edge inbound marketing strategies ... we realize how crucial the agriculture industry is,” said David Phelps, chief marketing ...
Breaking Biology Technology: