GE Healthcare this week released results from a pair of studies researching use of its MultiOmyx protein detection system in lymphoma and breast cancer.
The studies comprised an assessment of the company's nine-protein Hodgkin Lymphoma Profile assay, which it launched in July through its Clarient Diagnostic Services division, and an exploratory research effort using the system to evaluate known prognostic biomarkers in breast cancer.
Introduced by GE Healthcare in February and launched as a research device in May, the MultiOmyx platform uses antibodies conjugated to fluorescent dyes to stain proteins of interest in batches of two to four at a time. Researchers then image the stained tissue and deactivate the fluorescent dyes via a proprietary process. They can then stain the tissue with the next round of antibodies, multiplexing in an iterative fashion.
Currently, the system can multiplex up to 65 proteins in a single sample, and the company has antibodies to more than 175 markers ready for use with the platform. In experiments to test for background resulting from multiple staining cycles, GE researchers have found no added background after as many as 100 cycles.
In addition to its multiplexing abilities, the platform also allows researchers to obtain spatial information on the detected markers, offering subcellular resolution.
These capabilities make the system particularly well-suited to analysis of small samples, said Ken Bloom, Clarient's chief medical officer, noting that this niche is currently the primary focus of the company's MultiOmyx work.
For instance, he said, its HL Profile test – which is the first commercial release on the platform – "is really geared towards samples where the necessary [conventional immunohistochemistry] tests can't be performed with the limited tissue available."
In the lymphoma study released this week, company researchers sought to compare the performance of the HL Profile assay to conventional IHC methods, looking at 56 lymphoma cases to assess diagnostic concordance between the two methods. Their analysis found that the two methods agreed on 54 of the 56 cases and that in the two discordant cases the MultiOmyx system provided the correct diagnosis.
These results, Bloom said, help validate the performance of the HL Profile test, indicating that it can be an effective alternative to conventional testing in cases where samples are limited.
"Today [the assay] is a tool that prevents re-biopsy of patients to get more tissue," he said. "And what we demonstrated is that we could get the same answer with limited tissue."
In the future, however, the company plans not only to use the platform for cases where sample size is limited but to build better, more informative assays for use in samples of all sizes, Bloom noted.
"Right now the way we utilize it clinically is for samples where we can't address the fundamental questions with the amount of tissue available," he said. "We hope that what we are going to learn through being able to address the interconnection of all these protein interactions [using the MulitOmyx platform] will provide us with insights to treat patients either in a more personalized manner or better as an overall cohort."
The breast cancer study, which the company presented this week at the annual San Antonio Breast Cancer Symposium, is an example of using the platform for this sort of exploratory research. In the study, the researchers used the system to analyze 25 protein biomarkers associated with disease recurrence in more than 800 breast cancer cases, identifying four markers that showed a strong association with poor outcome.
The effort "wasn't necessarily looking for any [specific] prognostic signatures," GE researcher Nicole LePlante, lead author on the study, told ProteoMonitor, but was aimed more at simply evaluating the utility of recurrence markers previously identified in the literature. The researchers have also begun to use the data to investigate the markers' performance in specific breast cancer subtypes, she said.
Unlike in Hodgkins lymphoma, sample size is rarely an issue in analysis of primary breast tumors, Bloom said. However, he noted, the amount of such samples available for research purposes are often limited, making the MultiOmyx approach potentially valuable in this setting, as well.
Beyond that, he said, the company sees a potential role for the platform in profiling breast cancer and other metastases where sample size is again an issue.
A number of recent studies have "demonstrated that expression levels in the genomics of breast cancer metastasis don't always mirror that in the primary tumor," Bloom said. "And a number of guidelines have come out that suggest that if a metastatic lesion is available to biopsy, that should be performed because status like estrogen receptor status and HER2 protein status that guide therapy frequently change between the primary tumor and metastatic lesion."
"We anticipate that when it becomes time to test metastatic lesions, the availability of tissue is going to become problematic," he added. "So we anticipate that this technology might be very beneficial at that time."
This week's studies are the latest of several GE has published since launching the platform in February. In July, company researchers published a paper in the Proceedings of the National Academy of Sciences detailing use of the platform to measure 61 proteins in formalin-fixed paraffin-embedded tumor samples from 747 colorectal cancer patients.
It has also published several posters detailing research done on the platform, including a study done with University of Toronto researchers on co-localization of Her2/Neu, ER, PR, Ki67, and cytokeratin in triple-positive breast cancer and studies with State University of New York, Albany researchers on signaling and cell population dynamics in developing salivary glands.
In addition to lymphoma, and breast and colorectal cancer, GE also has programs using the platform for research in prostate and lung cancer and glioblastoma.