The June 2017 study involved profiling plasma samples from 94 clear cell (cc) RCC patients and 100 non-cancer controls.

The researchers did not find miRNA that could definitively distinguish between early-stage ccRCC and the controls. But later-stage cancers showed clear distinctions.

“Advanced tumors of stage III and IV showed specific miRNA profiles that significantly differ from both controls and cases at stage I and II, suggesting that our ability to detect ccRCC from circulating miRNA expression levels depends on the advancement of the disease,“ the authors stated.

They concluded that the results “contribute evidence that circulating miRNAs are associated with the progression of renal carcinoma. Plasma miRNA signatures specifically associated with late-stage disease may yield further insights into ccRCC pathogenesis and contribute to disease monitoring.”

miRNAs also show promise as a therapeutic tool.

As the authors of a 2013 paper described, “technological advances are enabling the synthesis of pre- or anti-RNA molecules within carrier vehicles that can be administered topically or systematically to induce generalized cell targeting.”5

“Once inside the cell,” they explained, “the miRNAs can serve as antagomirs and inhibit the function of another miRNA, or they can restore the levels of miRNAs that were suppressed or deleted and recover their function.”

But, the authors warned, the varied functions of individual miRNAs complicate targeting efforts: “by inhibiting a single miRNA we can block an oncogene but we could also suppress a tumor suppressor gene.”

Still, Dr Danesh said, with researchers around the world directing their attention at the role and potential of miRNAs in RCC diagnosis and therapy, our understanding of the small, single-strand RNA molecules and their ability to modulate gene expression is accelerating. And the potential of miRNAs in targeted therapy is alluring.

“We are trying to regulate the regulators of cancer,” he said. “So maybe we don’t have access to the gene that is specific for that cancer, but if we can manipulate the other genes that regulate the behavior of that gene, then we are really manipulating the cancer indirectly.

“This is something that I’m sure that in the next few years we’re going to see major advances in science and medicine. It’s going to be revolutionary.”

References

  1. Chanudet E, Wozniak MB, Bouaoun L, et al. Large-scale genome-wide screening of circulating microRNAs in clear cell renal cell carcinoma reveals specific signatures in late-stage disease. Int J Cancer. 2017 Jun 22. doi: 10.1002/ijc.30845 [Epub ahead of print]
  2. Cancer facts & figures 2017. American Cancer Society website. https://www.cancer.org/research/cancer-facts-statistics/all-cancer-facts-figures/cancer-facts-figures-2017.html. Accessed July 2017.
  3. Gu L, Li H, Chen L, et al. MicroRNAs as prognostic molecular signatures in renal cell carcinoma: a systematic review and meta-analysis. Oncotarget. 2015;6(32):32545-60.
  4. Tang K, Xu H. Prognostic value of meta-signature miRNAs in renal cell carcinoma: an integrated miRNA expression profiling analysis. Sci Rep. 2015;5:10272. doi: 10.1038/srep10272
  5. Dias F, Teixeira AL, Santos JI, et al. Renal cell carcinoma development and miRNAs: a possible link to the EGFR pathway. Pharmacogenomics. 2013;14(14):1793-803. doi: 10.2217/pgs.13.184