Early detection: Tattoo signals cancer – and more

People who are not ill and do not show any symptoms typically do not visit the doctor. And while most people know that preventive medical checkups for cancer, for example, are important, they still avoid them. They tend to be very hesitant because the doctor might detect a serious illness. In the future, a new type of implant could make it easier to go to a screening test or even eliminate the need for it entirely.

In this MEDICA-tradefair.com interview, Prof. Martin Fussenegger talks about an implantable tattoo that is designed to warn about diseases at a very early stage and explains why this type of early detection approach is especially beneficial for health care systems.

Prof. Fussenegger, we are talking about an implant that is designed to facilitate the early detection of cancer. How can we picture this implant?

Prof. Martin Fussenegger: Our implant, which we also refer to as a tattoo, consists of human cells, which we have modified to fulfill two functions. First, they continuously measure the level of calcium in the blood. Second, if this level stays elevated over an extended period, the cells produce an enzyme that converts the amino acid tyrosine into melanin, the natural pigment that also causes the tanning of skin by exposure to sunlight.

These cells are encapsulated in alginate/gelatin. The capsules measure about half a millimeter in diameter and are injected into a subcutaneous skin layer. Fibroblasts, which coat the gelatin capsule on the outside, connect to the bloodstream.

If the calcium level is permanently elevated, the tattoo cells produce melanin. The result is a dark spot that is visible on the skin. We know more than 300 different cancer types and about 40 percent of them cause high levels of blood calcium, which is usually precisely controlled in healthy people. The implant can detect a wide range of cancers, including the four most common types of breast, colon, prostate and lung cancer.

What prompted this development?

Fussenegger: There were two primary reasons. On the one hand, many people are still very hesitant to get an early screening test, because they might be worried about the possible results or for other reasons – and if we are really honest, nobody likes to do this.

On the other hand, we do not have early methods of detection for all of the more than 300 cancer types. That’s why there should be a technology that allows us to detect and cover large portions of the cancer spectrum without having to perform hundreds of tests.

Having said that, this also applies to other diseases that take a long time for development, including neurodegenerative diseases such as Alzheimer's or Parkinson's disease for example. Cancer was the model in our feasibility study, but we believe that we can equip the implant with different biomarkers to detect other diseases as well.

What are the advantages of this type of implant from your perspective?

Fussenegger: Our tattoo enables us to make the most common types of cancer visible – and at such an early stage to where they can likely still be cured and do not cause any symptoms. This always reminds me of what’s wrong with the way our health care systems work: We typically do not go to the doctor until we are already ill, have symptoms and the disease has already advanced to a point where we can’t be cured in many instances.

I think this is essentially also the most important message in all this: our health care systems need to invest more in the early detection of diseases to reduce the high costs tied to treating chronic and serious diseases.

What types of cells did you use in your study?

Fussenegger: For the feasibility study, we used HEK cells, human embryonic kidney cells. This is a specific line of cell culture that’s commonly used in laboratories. We believe it was important to test the implant in mouse models with human components and not by using mouse components.

Needless to say, in the future, it is desirable to use autologous cells that are taken from the patient to prevent an immune response.

You just brought up the future. What are your plans, now that the feasibility study has been completed?

Fussenegger: The work our university is able to do on its own has been completed with the mouse model and the feasibility study. We would now like to continue our tattoo development in preclinical studies with the help of professional risk financing and medical partners. Needless to say, this would imply tests with other primary cell types and studies in large animal models. I think in five years, we might actually be ready to enter Phase I clinical trials, meaning we might begin testing using human beings. Having said that, this depends on whether and when we find the right partners for this.