Cancer is the second most common cause of death worldwide. With COVID-19 putting treatments and screening services on hold, cancer mortality rates – already predicted to double over the next two decades – may rise faster than we anticipated. This pressing societal and medical issue can only be addressed with effective, tailored treatments.
A cancerous tumour develops when DNA mutates. This leads to a host of molecular, physiological and structural changes that result in a cell growing uncontrollably. How these changes occur remains largely a mystery.
Water is by far the main component within a cell and plays a crucial role in almost every cellular process. A group of scientists from the 'Molecular Physical-Chemistry' Group of the University of Coimbra (Portugal) and ISIS Neutron & Muon Source are focusing on its potential role in cancer development. They previously used neutron scattering on OSIRIS to observe the effect of the chemotherapy drug cisplatin on intracellular water.
The group's latest study, published in Structural Dynamics, compared the intracellular water dynamics in healthy human cells to cancerous cells using OSIRIS. Their aim was to shed light on the elusive normal-to-malignant cell transition.
The scientists studied three types of cancer cells and their healthy equivalents: prostate cancer, the most common cancer in men in Western countries; triple-negative breast cancer, which is prevalent in younger women and tends to be very aggressive; and osteosarcoma, the most frequent bone cancer in children, with a survival rate of less than 20%.
All three types of cancer cells studied were found to have a significantly lower flexibility than their non-cancerous counterparts, with breast cancer deviating the most from the healthy baseline. This confirmed the clear-cut differences between types of cancer shown in previous literature.
The scientists relied on an innovative method to examine intracellular water, particularly its dynamical profile. Water interacts with the protein surface of biomolecules to form a structure called a hydration shell, closely related to protein functionality.
Despite the differences in cellular flexibility, “the water molecules within the biomolecules' hydration layers seemed to remain unaffected by either healthy or malignant cells, or by cancer type," explains Dr Maria Paula Marques, one of the scientists working on this pioneering research. She was awarded the ISIS Society Impact Award in 2019 for her work on a drug´s impact on intracellular water.
The group observed significant differences in the dynamics of water within the cytoplasm between healthy and malignant cells. Why water dynamics varies between cell regions is currently unknown. "Further studies will elucidate this very important issue," says Dr Marques; “More data is needed, in a broader set of human cells."
These types of changes in intracellular water could be a fantastic tool for clinicians to identify cancerous tissue, as well as the type of cancer. A more accurate and early diagnosis of malignancy means the patient's treatment could be tailored to them, enhancing chemotherapy success.
