A team of scientists at the Francis Crick Institute has recently developed a new technique to study tissue samples in three-dimension (3D). It has uncovered that onset and proliferation of pancreatic cancers can occur in two distinct ways, solving an age-old mystery of how tumors form.
It could also help scientists and researchers to obtain more information from tissue biopsies and will possibly lead to better treatment for pancreatic cancers, according to the team whose findings are published in the journal Nature.
The pancreas plays an important role in digestion that relies on network of ducts linking it to other organs involved in the digestive system. Most common pancreatic cancers are found in these ducts, but until now, it was only possible to observe the 2D slices of ductal tumors containing a mysterious variety of abnormal shapes.
In order to explore the origins of pancreatic cancer, the team spent almost six years to develop a new method for analyzing cancer biopsies in 3D, co-lead author Dr. Hendrik Messal said. The newly developed technique showed that the cancers form in the duct wall and either grow into the ducts or outwards depending on the duct size, he added. It explains differences in shapes that are seen in the 2D slices for decades.
By examining the developing tumor in 3D, the scientists identified two different types of cancer formation that orginated from ductal cells: ‘endophytic’ and ‘exophytic’ tumors which grow inwards and outwards respectively.
To check what makes cancerous cells grow in a specific way, the team studied detailed 3D images and worked closely with biophysicists who developed sophisticated computer models.
They made a simulation of the ducts, describing geometry of individual cell to understand tissue shape, Dr Silvanus Alt, co-lead author and biophysicist at Crick said.
Both the model and experimental results confirmed that the tumor develop outwards when the duct diameter was less than 20 micrometers.
Since, it is defined that the pancreatic cancers can develop in two distinct ways, the scientists can start investigating whether one is likely to be more aggressive or spread in a different way. In future, this could also lead to improved diagnostic or treatment options.
When the technique was applied to other organs, the team found that cancer in the airways of the lungs and ducts in the liver behave in a similar manner, showing that the newly developed mechanism is confined to pancreatic cancer and can be applied to other cancers.