After two and a half years of intensive work, scientists from the Laboratory of Biophysics of the Institute of Physics of the Czech Academy of Sciences, led by Oleg Lunov, have presented a breakthrough DNA nanostructure based platform, which allows for the targeted influence of lysosomal functions in cells. This research opens up new possibilities for the development of advanced therapeutic methods which in the future could be used, for example, in the treatment of cancer, neurodegenerative and autoimmune diseases. The research results, achieved in collaboration with colleagues from Arizona State University, the Institute of Clinical and Experimental Medicine, the Institute of Experimental Medicine of the Czech Academy of Sciences and the Institute of Physiology of the Czech Academy of Sciences, were published in the prestigious Chemical Engineering Journal.
DNA nanotechnology is a rapidly developing field offering new tools for biomedicine. DNA nanotechnology is being intensively studied by teams around the world. What makes nanotechnology based on DNA nucleotides, the basic building blocks of genetic information, potentially better than the technologies already used in clinical practice today? No other biological material so far has demonstrated so many positive properties that can be used for the design of new drugs as DNA. Perhaps that is why the mighty nature selected it as a hiding place for the code guiding its development for better or worse for millions of years. With a slight exaggeration, it is easy to design such nanostructures in almost any shape and their chemical synthesis is also relatively simple. Another undeniable advantage is that for the organism, they are also non-toxic and degradable.
We believe that all of us are more or less familiar with the term "lysosome". Probably each of us can recall that at high school we learnt that it is something like a cellular stomach. A place where everything that a cell eats is digested. Correct! But that is not the whole story!
Other equally important functions of lysosomes have been discovered ensuring proper functioning of the organism and maintenance of its homeostasis. At the same time, phenomena and diseases have been described that are affected by lysosomes not functioning the way they should. We can mention, for example, the behaviour of cancer cells, participation in the regulation of cell death; metabolic, autoimmune and inflammatory disorders or even more than 50 hereditary diseases where close association with improper function of lysosomes has been detected.
The research of the Laboratory of Biophysics’ team focused on the use of DNA nanostructures (DNs) to influence lysosomes. The team from Arizona State University includes experts in the field of synthesis and characterization of highly stable DNA nanostructures, and scientists from FZU (in collaboration with IKEM and BIOCEV) have designed a universal platform that can modulate various cellular functions depending on the concentration and surface treatment of the nanostructures.
"One of the main challenges of the research was to design a platform that could effectively target lysosomes and influence their functions without unwanted toxicity. The DNA nanostructures we developed can modulate a range of cellular functions as needed, representing a significant advance in the field of biomedicine," stated Petra Elblová, first author of the published work and PhD student of the Laboratory of Biophysics.
"We employed an innovative approach for targeting lysosomal functions known as lysosomal interference. This method was recently discovered through the use of self-assembled DNA nanoframeworks. Instead, we utilized biodegradable DNA nanostructure-based carriers to deliver functional peptides into lysosomes, resulting in controlled manipulation of cellular functions via lysosomal interference," added Oleg Lunov, head of the Laboratory of Biophysics.
It has been mentioned above that DNA nanostructures are non-toxic and degradable. So how could they be used to modulate lysosomal activity? DNA nanostructures were surface-modified by coating them with relatively short peptides – decalysin and aurein.
By using peptides for surface modification of nanostructures, it was possible to specifically modulate lysosomal activity, which was manifested, for example, by changes in cell morphology, regulation of immune signals and cell death. Low concentrations of nanostructures coated with the peptide decalysin (K10) increased the acidity of lysosomes, thereby affecting the metabolic activity of cells. Conversely, nanostructures with the peptide aurein (EE) stimulated alkalization of lysosomes and activation of immune signalling pathways. High concentrations of K10 caused lysosomal enlargement and changes in cell shape without killing them, while high concentrations of aurein nanostructures led to lysosomal rupture and mitochondrial damage, resulting in cell death.
Synthesis and stability of DNA nanostructures
The key role in successfully influencing the function and behaviour of lysosomes is played by very small and stable nanostructures consisting of six strands of DNA. These nanostructures are coated with a layer of peptides that increase their strength and resistance in the body's environment. The nanostructures are also biodegradable, meaning that in lysosomes they can break down into smaller parts. These parts then leak into the rest of the cell and affect various cellular processes.
Promising role in the fight against cancer
One of the most interesting applications of this technology is the targeted destruction of cancer cells. Research has shown that high concentrations of aurein-coated DNA nanostructures cause extensive damage to lysosomes, leading to their rupture and the subsequent death of cancer cells, including very resistant glioblastoma cells. This platform thus represents a promising avenue for the development of new therapeutic methods that could effectively destroy cancer cells by disrupting lysosomal functions.
Alexandr Dejneka, head of the Division of Optics of the Institute of Physics of the Czech Academy of Sciences, praised the contribution of the entire team: “Research of this scale would not be possible without the extraordinary commitment of all collaborating researchers. This project shows how important it is to connect research teams from different institutions that work together to achieve significant results for biomedicine.”
This groundbreaking research not only brings new knowledge about the use of DNA nanostructures, but also paves the way for the development of innovative procedures that can improve the treatment of a number of serious diseases.
On the occasion of the Student Conference of the Division of Optics, which will take place on 25 November 2024, we would like to invite you to a presentation focusing on part of this project as well as on our other areas of interest. Our student Petra Elblová will try to explain some of the key experimental findings of this project. Student Alicia Calé will introduce other aspects of biomedical research, such as the effects of different mechanical environments on human cells. This is an important aspect of human knowledge, because different tissues of our body are subject to different mechanical influences, which affects, for example, the absorption of drugs and the behaviour of cells as such.
You are cordially invited as are your questions, which can help us look at the problem from different angles.