Research ArticleCancer Diagnostics

Micro-NMR for Rapid Molecular Analysis of Human Tumor Samples

Science Translational Medicine  23 Feb 2011:
Vol. 3, Issue 71, pp. 71ra16
DOI: 10.1126/scitranslmed.3002048

You are currently viewing the editor's summary.

View Full Text

Log in


A Micro-NMR Smart Phone for Detecting Cancer

Smart phones may have provided millions of people with hours of mindless entertainment, but their real value may lie in the hands of clinicians at the patient’s bedside. Accurate diagnosis and staging of tumors through analysis of core biopsies is essential for ensuring that patients receive rapid treatment with the most appropriate cancer drugs. However, current techniques for analyzing tumor biopsies such as immunohistochemistry and flow cytometry are costly and time-consuming and require more tissue than biopsies often contain, necessitating that patients be subjected to repeat biopsies. Enter Weissleder and his team with their portable micro-NMR (nuclear magnetic resonance) device operated by smart phone technology that enables accurate diagnosis of malignant tumors from the scarce cancer cells present in fine-needle aspirate biopsies.

Weissleder’s micro-NMR system uses nanoparticle-based magnetic affinity ligands to detect expression of protein markers that are associated with cancer. First, the investigators looked at the expression of nine protein markers in fine-needle aspirates taken from suspected malignant abdominal lesions in a cohort of 50 patients. Using detection of their nine-marker signature by micro-NMR, they correctly identified 44 patients as having malignant tumors, with verification of the diagnoses by standard techniques such as core biopsy, imaging, and clinical assessment. Using a four-protein marker signature (MUC-1, HER2, epidermal growth factor receptor, and EpCAM), Weissleder and his team were able to increase the diagnostic accuracy of their micro-NMR system still further to 96%. This exceeded the 84% accuracy of immunohistochemistry, a gold standard of cancer diagnosis, and was much faster, providing a diagnosis within 1 hour instead of 3 days. To validate their findings, the investigators tested their four-protein marker signature in another 20 patients with suspected abdominal malignancies and this time obtained a 100% accurate diagnosis. The micro-NMR cancer diagnostic system has the advantages of speed and accuracy, but the authors do point out several caveats. They discovered that protein marker expression is heterogeneous within and between tumors and varies depending on the location of the final needle aspirate site. They also point out that because of rapid protein degradation even at 4°C, the biopsies either should be analyzed immediately or should be carefully preserved. Despite these caveats, this portable micro-NMR device, which is easy to operate with smart phone technology, could improve the speed and accuracy of cancer diagnosis, leading to earlier and more effective treatments for cancer patients.

Footnotes

  • * These authors contributed equally to this work.

  • Citation: J. B. Haun, C. M. Castro, R. Wang, V. M. Peterson, B. S. Marinelli, H. Lee, R. Weissleder, Micro-NMR for Rapid Molecular Analysis of Human Tumor Samples. Sci. Transl. Med. 3, 71ra16 (2011).