NEW HAVEN, Conn., Dec. 7, 2011 /PRNewswire/ — Mira Dx® today notes the publication of breakthrough research showing that the KRAS-variant acts as a biomarker of poor survival and worse response to treatment for patients with ovarian cancer(1). Ovarian cancer patients with the KRAS-variant are twice as likely to die of their ovarian cancer, and three times more resistant to standard platinum chemotherapy compared to ovarian cancer patients who do not carry the variant. The KRAS-variant is found in up to 25% of newly diagnosed ovarian cancer patients. Studies are being actively pursued to identify which chemotherapeutic agents work best for these patients.

The KRAS-variant is a germ-line mutated version of the KRAS oncogene, which plays a fundamental role in cancer biology in numerous cancer types. The variant was previously shown to predict an increased risk of developing several cancers, and most strongly ovarian cancer for women from families with histories of breast and ovarian cancers. The variant has also been associated with poor outcome in several cancer types and altered response to therapy in studies looking at Cetuximab.

“We are very excited with this finding as it underscores the importance of the KRAS-variant for all ovarian cancer patients, and more broadly supports the role of microRNA genetics in tumor biology. We look forward to completing additional clinical studies to add [click to continue…]


Yale Cancer Center researchers have shown that a tiny genetic variation predicts chances of survival and response to treatment for patients with ovarian cancer.

The findings, published in the journal Oncogene, provide new insights into the biology of a new class of cancer marker and suggest a genetic test may help guide the treatment of women with ovarian cancer.

“This gives us a way to identify which women are at highest risk for resistance to platinum chemotherapy, the standard treatment for ovarian cancer, and helps identify ovarian cancer patients with [click to continue…]


The miR-200 family is a particularly nasty group of microRNAs. Changes in miR-200 family levels have been associated with enhanced tumorigenesis and significantly correlated with decreased survival. 

miR-200 family members are associated with resistance to several chemotherapy drugs: docetaxel  in non-small cell cancer cells1, cisplatin in breast cancer cells2, and gemcitabine in cholangiocarcinoma cells.

It has been shown that many microRNAs play an important role in regulating metastasis, the ultimate cause of death of most cancer patients, and in particular, miR-200 is responsible for direct enhancement of distant metastases of breast cancer3.

Additionally miR-200 family members are significantly over-expressed in human ovarian cancer4 and likewise are a factor in the etiology of endometriosis5.

  1. Rui W, Bing F, Hai-Zhu S, Wei D, Long-Bang C.  (2009)  Identification of microRNA profiles in docetaxel-resistant human non-small cell lung carcinoma cells (SPC-A1).  J Cell Mol Med [Epub ahead of print]  [abstract]
  2. Pogribny IP, Filkowski JN, Tryndyak VP, Golubov A, Shpyleva SI, Kovalchuk O. (2010) Alterations of microRNAs and their targets are associated with acquired resistance of MCF-7 breast cancer cells to cisplatin. Int J Cancer [Epub ahead of print] [abstract]
  3. Dykxhoorn DM, Wu Y, Xie H, Yu F, Lal A, Petrocca F, Martinvalet D, Song E, Lim B, Lieberman J.  (2009) miR-200 enhances mouse breast cancer cell colonization to form distant metastasesPLoS One 4(9), e7181.  [abstract]
  4. Iorio MV, Visone R, Di Leva G, Donati V, Petrocca F, Casalini P, Taccioli C, Volinia S, Liu CG, Alder H, Calin GA, Ménard S, Croce CM. (2007) MicroRNA signatures in human ovarian cancer. Cancer Res 67(18), 8699-707. [abstract]
  5. Filigheddu N, Gregnanin I, Porporato PE, Surico D, Perego B, Galli L, Patrignani C, Graziani A, Surico N. Differential expression of microRNAs between eutopic and ectopic endometrium in ovarian endometriosis. J Biomed Biotechnol 2010:369549. [abstract]

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ARRA Funding Supports microRNA Research

by Chris on October 28, 2009

in News

from – RNAi News

NIH has awarded millions to support microRNA research under the American Recovery and Reinvestment Act.  Two of the largest grants went to Dr. Sohail Tavazoie at the Rockefeller University and Dr. Carlo Croce at the Ohio State University.  Tavazoie studies miRNAs that can be used to predict how a cancer patient will respond to chemotherapy, focusing on colorectal cancer, and Croce studies how the loss of one specific miRNA can be used to predict how a patient will repond to demethylating agents. (read more)