Expression patterns of microRNAs appear altered in colon cancer, and associated with poor outcomes

January 29, 2008

Preliminary research has found an association between certain microRNA expression patterns and poor survival and treatment outcomes for colon cancer, according to a study in the January 30 issue of JAMA.

Colon cancer is a major cause of cancer death worldwide. Colorectal cancer is the third most common and second leading cause of cancer death in the United States. “Even though 5-year mortality rates have modestly declined over the last 3 decades, there is still a need to identify new prognostic biomarkers and therapeutic targets for this disease,” the authors write. They add that microRNAs have potential as diagnostic biomarkers and therapeutic targets in cancer.

MicroRNAs are 18 to 25 nucleotide, noncoding RNA (ribonucleic acid) molecules that have been found to regulate a variety of cellular processes and may also have a role in the development of cancer cells. The prognostic potential of microRNAs has been demonstrated for chronic lymphocytic leukemia, lung cancer and pancreatic cancer, according to background information in the article. No study has evaluated the association between microRNA expression patterns and colon cancer prognosis or therapeutic outcomes.

Aaron J. Schetter, Ph.D., M.P.H., and Curtis C. Harris, M.D., of the National Cancer Institute, National Institutes of Health, Bethesda, Md., and colleagues evaluated microRNA profiles of colon tumors and paired nontumorous tissue to study their potential role in tumor formation, diagnosis and therapeutic outcome in colon cancer. The study included 84 patients from Maryland; associations were validated in a second, independent group of 113 patients from Hong Kong.

Thirty-seven microRNAs were differentially expressed in tumor tissues by microRNA microarray analysis in the Maryland test cohort. Expression patterns of five tested microRNAs were validated in the Hong Kong cohort. “The discriminatory power of 5 microRNAs to differentiate between tumor and nontumorous tissue suggests that predictable and systematic changes of microRNA expression patterns may occur during tumorigenesis and may be representative of sporadic colon adenocarcinomas,” the authors write.

“… we found systematic differences in microRNA expression patterns between colon tumors and paired nontumorous tissue. Tumors with high expression of miR-21 [a microRNA] was associated with poor survival outcome and poor response to adjuvant chemotherapy in 2 independent cohorts, independent of staging and other clinical covariates suggesting that miR-21 may be a useful diagnostic biomarker for colon adenocarcinomas and survival prognosis including response to therapy.”

“Additional studies are required to demonstrate a causal link with miR-21 and the progression of colon cancer to determine the potential of miR-21 as either a biomarker or therapeutic target,” the researchers write.

Source: JAMA and Archives Journals

Explore further: Colon cancer may yield to cellular sugar starvation

Related Stories

Colon cancer may yield to cellular sugar starvation

August 6, 2009

Scientists at the Johns Hopkins Kimmel Cancer Center have discovered how two cancer-promoting genes enhance a tumor's capacity to grow and survive under conditions where normal cells die. The knowledge, they say, may offer ...

Novel marker of colon cancer

October 23, 2008

Colon cancer ranks second of all gastrointestinal malignant tumors, it is one of the leading causes of cancer-related deaths worldwide. Until now, several molecules have been reported to play an important role in gastroenterological ...

Prostate cancer: Watchful wait or vaccinate?

February 1, 2008

Researchers at the University of Southern California have developed a prostate cancer vaccine that prevented the development of cancer in 90 percent of young mice genetically predestined to develop the disease. In the February ...

Drug for anemic cancer patients raises risk of death

February 26, 2008

Millions of cancer patients take drugs to boost their red blood cells and health when they become anemic after chemotherapy. But a new study by Northwestern University's Feinberg School of Medicine shows these drugs, called ...

Recommended for you

How the finch changes its tune

August 3, 2015

Like top musicians, songbirds train from a young age to weed out errors and trim variability from their songs, ultimately becoming consistent and reliable performers. But as with human musicians, even the best are not machines. ...

Machine Translates Thoughts into Speech in Real Time

December 21, 2009

( -- By implanting an electrode into the brain of a person with locked-in syndrome, scientists have demonstrated how to wirelessly transmit neural signals to a speech synthesizer. The "thought-to-speech" process ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.