Engineering Cancer Cells
Cancer is one of the most dreaded and painful diseases of our age. It is the second most common disease in India. About a quarter of a million people die of cancer in India every year. A better understanding of the underlying mechanism will go a long way in improving treatment and management of the disease. Several research groups and health care specialists worldwide are doing extensive research in trying to understand the disease and develop treatments.
Dr. Kaushik Chatterjee’s group in the Department of Materials and Engineering in collaboration with Dr. Annapoorni Rangarajan’s group in Biological Sciences in the Indian Institute of Science, Bangalore is one such team involved in this endeavour. They are trying to understand the disease by mimicking cancer tissues in the lab. “Our goal, broadly, is to recreate a model that is more relevant to how it actually occurs inside the body,” says Dr. Chatterjee. Traditionally, the study of cancer has been done by observing layers of cells grown on a petri plate or flask. But this method of experimentation fails to replicate the actual situation. “A 3D model tissue is much more realistic than a petri dish format,” explains Dr. Chatterjee, “you understand how cells interact with each other – how they grow around each other. You also understand their interaction with the matrix – the substance surrounding them.” It also gives more accurate insights: for example, in cancer treatment, the dosage of drugs is not felt equally by all the cells – the interior cells often remain largely unaffected – observations such as this can be made only with a 3D model.
In order to engineer the tissue, cancer cells are grown on scaffolds - support structures made from polymers, similar to the scaffolds used in the construction of a building. The cells are then left on their own to multiply and form the cancerous tissue. These tissues can then be subjected to further experimentation for understanding cell growth and observing the action of a drug on the tissue.
The group has already tested whether these tissues are able to mimic cancer tissues. The engineered tissues were injected into healthy mice. It was observed that not only did these cells grow faster as compared to those derived from a petri dish, they also metastatised and spread to other organs throughout the body.
Earlier, the team was using cells derived from cell lines maintained only for experimentation. Currently, they have sourced samples from hospitals in Bangalore and are trying to develop tissues from these in order to have a more targeted approach. This is more challenging as these clinical samples contain a mixed population of cells, and need to be purified to understand the role of these different cells.
This is only one of the many challenges that the group faces, though. “Cells in a petri dish are so much more convenient!” Dr. Annapoorni exclaims. “They’re transparent, so they can be monitored whenever one wishes, and most microscopy techniques are made for this format.” But 3D tissue models are non-transparent and observing them is difficult. Tissue engineering is a relatively new and hence, ‘non-standard’ approach, and therein lies the major challenge.
Gowri Balachander, a student pursuing her Ph.D. research in the Center for Biosystems Science and Engineering, works jointly in both the labs. The group plans to work with a mix of various cells - like fibroblasts, which secrete protein, or endothelial cells, which line blood vessels - in the future. This will help gauge how cancer cells interact with each other and with other entities surrounding them. “We hope to engineer ideal mimics that will get us closer and closer to how cancer in natural systems behaves, and hopefully this will help us develop strategies to aid in the field of medicine,” says Gowri who is excited to undertake this interdisciplinary study of applying engineering strategies to tackle a biomedical challenge.
Dr Kaushik Chatterjee is an Assistant Professor in the Department of Materials Engineering, Indian Institute of Science. He can be reached at +91-80-2293-3408.