Study Published in International Journal of Oncology Shows Potential for microRNAs to Determine Risk of Recurrence in Colorectal Cancer
PHILADELPHIA, PA and REHOVOT, ISRAEL, Mar 20, 2012 (MARKETWIRE via COMTEX) --Rosetta Genomics, Ltd. (NASDAQ: ROSG), a leading developer and provider of microRNA-based molecular diagnostics, today announced that data from a study investigating the ability of microRNA expression to determine the risk of disease recurrence in colorectal cancer patients was published in the online edition of the International Journal of Oncology and is expected to appear in the upcoming print edition. The article, entitled "Tumor microRNA-29a expression and the risk of recurrence in stage II colon cancer," can be accessed at http://www.spandidos-publications.com/confirmCorrespondingEmail?transactionId=3078312e33363161366462343330636264703430.
The study compared the microRNA (miRNA) profiles in the primary tumor of patients with recurrent and non-recurrent colorectal cancer. The study included 110 patients, 51 (46%) with stage I and 59 (54%) with stage II disease, who underwent curative colectomies without adjuvant therapy and for whom reliable miRNA expression data was available. RNA was extracted from formalin-fixed paraffin-embedded tumor samples. Initial profiling, using microarrays, was done to identify potential biomarkers of recurrence. The miRNA expression was later verified by quantitative real-time polymerase chain reaction (qRT-PCR). The findings compared the miRNA profiles between patients who had a recurrence within 36 months of surgery (bad prognosis group, n=23 or 21%) and those who did not (good prognosis group, n=87 or 79%) in the entire group and within each stage.
In stage II patients, one miRNA, miR-29a, showed a clear differential expression between the good and bad prognosis groups (p=0.028). High expression of miR-29a was associated with a longer disease-free survival on both univariate and multivariate analyses. Using miR-29a, the positive predictive value for non-recurrence was 94% (2 recurrences among 31 patients). The differential expression of miR-29a was verified by qRT-PCR, showing a similar association of this miRNA with disease-free survival. The results showed that none of the 903 miRNAs tested showed differential expression between stage I patients with good and bad prognosis.
Commenting on these data, study collaborator, Baruch Brenner, M.D., Institute of Oncology, Davidoff Center, Rabin Medical Center, Beilinson Hospital and Sackler Faculty of Medicine, Tel Aviv University, both in Israel, noted, "The risk of recurrence following successful complete resection is high in stage II and III disease. Consequently, most of these patients will receive additional treatment including postoperative (adjuvant) chemotherapy and preoperative (neoadjuvant) or postoperative (adjuvant) chemo-radiotherapy. However, the majority of patients receiving neoadjuvant and/or adjuvant therapy, which are associated with significant morbidity and even long-term sequelae and mortality, do not need it."
Dr. Brenner continued, "The current study suggests a potential prognostic role of miR-29a in patients with resected stage II colon cancer. Patients who did not experience a recurrence within three years from the resection of their primary tumor had significantly higher expression levels of this miRNA compared with patients who did have a recurrence within the same time. To further support the prognostic role of miR-29a, high expression levels of this miRNA correlated not only with the risk of recurrence, but also with the duration of disease-free survival."
"Current methods for stratifying patients with colorectal cancer by their prognosis are still mainly based on the extent of the local tumor spread and do little to distinguish between patients who do and those who do not need additional treatment," stated Kenneth A. Berlin, President and Chief Executive Officer of Rosetta Genomics. "Colorectal cancer is one of the most common cancers. Globally, more than 500,000 people die of this disease each year, making it the third most common cancer death worldwide. Data from this study demonstrate that miR-29a has the potential to serve as a biomarker of the risk of recurrence in stage II colon cancer, a finding that may have important implications for patient care. Informed decision-making using a test with a high positive predictive value may spare patients unnecessary and sometimes toxic post-surgery treatment, and may identify which patients to treat more aggressively."
About miRview(R) Products miRview(R) are a series of microRNA-based diagnostic products offered by Rosetta Genomics. miRview(R) mets and miRview(R) mets^2 accurately identify the primary tumor type in primary and metastatic cancer including Cancer of Unknown Primary (CUP). miRview(R) squamous accurately identifies the squamous subtype of non-small cell lung cancer, which carries an increased risk of severe or fatal internal bleeding and poor response to treatment for certain therapies. miRview(R) meso diagnoses mesothelioma, a cancer connected to asbestos exposure. miRview(R) lung accurately identifies the four main subtypes of lung cancer using small amounts of tumor cells. miRview(R) tests are designed to provide objective diagnostic data; it is the treating physician's responsibility to diagnose and administer the appropriate treatment. In the U.S. alone, Rosetta Genomics estimates that 200,000 patients a year may benefit from the miRview(R) mets and miRview(R) mets2 test, 60,000 from miRview(R) squamous, 60,000 from miRview(R) meso and more than 1 million patients worldwide from miRview lung. The Company's tests are offered directly by Rosetta Genomics in the U.S., and through distributors around the globe. For more information, please visit www.mirviewdx.com. Parties interested in ordering the test can contact Rosetta Genomics at (215) 382-9000 ext. 309.
About microRNAs microRNAs (miRNAs) are recently discovered, small RNAs that act as master regulators of protein synthesis, and have been shown to be highly effective biomarkers. The unique advantage of microRNAs as biomarkers lies in their high tissue specificity, and their exceptional stability in the most routine preservation methods for biopsies, including Formalin Fixed Paraffin Embedded (FFPE) block tissue and fine needle aspirate (FNA) cell blocks. It has been suggested that their small size (19 to 21 nucleotides) enables them to remain intact in FFPE blocks, as opposed to messenger RNA (mRNA), which tends to degrade rapidly. In addition, early preclinical data has shown that by controlling the levels of specific microRNAs, cancer cell growth may be reduced. To learn more about microRNAs, please visit www.rosettagenomics.com .
About Rosetta Genomics Rosetta Genomics develops and commercializes a full range of microRNA-based molecular diagnostics. Founded in 2000, the company's integrative research platform combining bioinformatics and state-of-the-art laboratory processes has led to the discovery of hundreds of biologically validated novel human microRNAs. Building on its strong patent position and proprietary platform technologies, Rosetta Genomics is working on the application of these technologies in the development and commercialization of a full range of microRNA-based diagnostic tools. The Company's miRview product line is commercially available through its Philadelphia-based CAP-accredited, CLIA-certified lab.
Forward-Looking Statements Various statements in this release concerning Rosetta's future expectations, plans and prospects, including without limitation, the potential of microRNAs in the diagnosis and treatment of disease, constitute forward-looking statements for the purposes of the safe harbor provisions under The Private Securities Litigation Reform Act of 1995. Actual results may differ materially from those indicated by these forward-looking statements as a result of various important factors, including risks related to: Rosetta's approach to discover microRNA technology and to work on the application of this technology in the development of novel diagnostics and therapeutic tools, which may never lead to commercially accepted products or services; Rosetta's ability to obtain, maintain and protect its intellectual property; Rosetta's ability to enforce its patents against infringers and to defend its patent portfolio against challenges from third parties; Rosetta's need and ability to obtain additional funding to support its business activities; Rosetta's dependence on third parties for development, manufacture, marketing, sales, and distribution of products; Rosetta's ability to successfully develop its products and services; Rosetta's ability to obtain regulatory clearances or approvals that may be required for its products and services; the ability to obtain coverage and adequate payment from health insurers for the products and services comprising Rosetta's technology; competition from others using technology similar to Rosetta's and others developing products for similar uses; Rosetta's dependence on collaborators; and Rosetta's short operating history; as well as those risks more fully discussed in the "Risk Factors" section of Rosetta's Annual Report on Form 20-F for the year ended December 31, 2010 as filed with the Securities and Exchange Commission. In addition, any forward-looking statements represent Rosetta's views only as of the date of this release and should not be relied upon as representing its views as of any subsequent date. Rosetta does not assume any obligation to update any forward-looking statements unless required by law.
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SOURCE: Rosetta Genomics, Ltd.