Cancer is a disease that affects everyone, regardless of age, gender or race. According to the American Cancer Society, one out of every two men and one out of every three women will develop cancer. One out of every four men and one out of every five women will ultimately succumb to it.
The war against cancer has been raging since as early as 1600 B.C., when a reference to breast cancer was made in the Edwin Smith papyrus, an ancient Egyptian medical text. As human society advanced, so too did our success against cancer mortality. Thanks to recent advancements in computer technology and microfluidics (the behavior and manipulation of very small amounts of fluid), researchers have been able to develop a new set of weapons for the fight against this deadly malady.
One company, RainDance Technologies, has caught the attention of GE Ventures and other investors, and recently closed an additional $16.5 million in funding. RainDance has developed the RainDrop System, which uses a modified “digital” version of a well-established technique called PCR (polymerase chain reaction) to analyze DNA noninvasively in bodily fluids to look for genetic variations associated with cancer or other complex diseases.
The combination of droplet microfluidics and digital PCR technology in the RainDrop System can cut costs significantly and saves precious time. Consequently, scientists can conduct more research in less time for less money, while delivering highly sensitive and precise genetic mutation results.
While this technology is currently for research use only, it could eventually be used in the diagnosis and prognosis of congenital genetic disorders, such as autism, Crohn’s disease and thrombophilia, or to perform surveillance for low-level pathogens in a patient (e.g., assessing latent HIV infection, subtyping viral infections or identifying bacterial infections).
However RainDrop is ultimately used, one thing’s certain: this technology takes us closer to winning the war against cancer. To learn more about RainDance and what this technology could mean for the future of cancer research, we asked Alex de Winter, partner at GE Ventures, about his company’s latest investment.
How does the RainDrop System look for cancer?
The first thing to understand is that cancer is a disease of the genome. That is to say, cancer is at its root caused by errors in a patient’s genetic material (their DNA). As the cells in our bodies go about their business, some naturally die, and when they die, the contents of the cells spill into the bloodstream for eventual removal by the liver and kidneys. So if you take a blood sample and examine it, you’ll find DNA from cells that have recently died. In a cancer patient, some of the DNA in the bloodstream will come from cancer cells, and because cancer is a disease of the genome, the cancer DNA usually differs from the patient’s DNA.
The RainDrop System is a very sensitive instrument for detecting DNA from cancer cells. This is not an easy thing to do, because the signal from cancer DNA would normally be swamped by the signal from the patient’s regular DNA, especially in the case of early-stage cancer, when there are fewer malignant cells.
What the RainDrop System actually does is it takes DNA from a fluid sample, and divides it into 10 million tiny aqueous droplets, all suspended in a stream of oil. To each droplet, it adds reagents that will become fluorescent if a genetic variant characteristic of cancer is present in the droplet. After carrying out the reaction, the droplets flow past a laser and detector, and the instrument counts the number of fluorescent and blank droplets.
How do oncologists currently search for cancer, and how does the RainDrop System compare?
The way oncologists currently search for cancer depends on the type of cancer. For example, for breast cancer they use mammograms and sometimes MRIs, for lung cancer they use CT scans. In both cases, oncologists are looking for an unusual mass of tissue that could be cancer.
These methods work well enough, though they do have some downsides. For example, mammography and CT scans expose the patient to a small dose of radiation. The imaging-based methods are limited by the size of the lump of tissue that they can see, and it’s difficult to detect lumps below a certain threshold size.
After a suspicious lump is detected, oncologists usually take a biopsy, removing a small sample of tissue from the lump to assess whether the lump is cancer and to characterize the tumor. RainDance’s technology has the potential in the future to characterize cancer from noninvasive fluid samples, thereby making the measurement much less invasive, rapid and cost effective.
GE Ventures recently contributed part of an additional $16.5 million in funding that RainDance Technologies raised. What about the company did GE find attractive?
We like the team first and foremost. We had been tracking RainDance for a while, and have been impressed with the top management of CEO Roopom Banerjee, CFO Alf Merriweather, CTO Darren Link, as well as with the outstanding team they have assembled around them. They’ve proven to be exactly the sort of entrepreneurial team you want to invest in and support.
The market and timing have also lined up nicely for RainDance. It has been well documented that DNA sequencing has advanced rapidly over the last decade, becoming cheaper and faster each year. As we surveyed the genomics market, it became clear to us that DNA sequencing is no longer a significant bottleneck in the overall workflow.
One area that has emerged as a hurdle in genomics is sample preparation, getting samples ready to be sequenced. RainDance’s ThunderStorm System and ThunderBolts Cancer Panel target this bottleneck for generating high-quality sequencing results from targeted gene panels.
Images courtesy of RainDance Technologies.