There are many different types of cancer and all of them are terrible. It is quite interesting because they are technically different diseases and are treated using different therapies. But they still have a lot in common and scientists from the University of Adelaide have now designed a new molecule, which is showing a great promise against many cancers.
PCNA protein, which copies DNA, is overexpressed in 90 % of cancers. Image credit: BruceBlaus via Wikimedia (CC BY-SA 4.0)
Cancer is basically a mistake in cell division. It is some sort of a mutation that causes cancer cells to grow, producing tumours. This is the essence of cancer, even though there are many different types of cancer depending on the location of cancer cells, their division, spread and so on. Cancer cells have the human sliding clamp, also known as proliferating cell nuclear antigen (PCNA), which is required for DNA replication. PCNA is something that allows cancer cells to grow quickly, which makes it a perfect target for a new generation of cancer drugs. PCNA is a donut-shaped protein, which copes DNA when it moves through the middle of it.
Knowing how PCNA works opens doors for innovative treatments. If the function of PCNA was inhibited, it could no longer replicate DNA and therefore cancer couldn’t grow. This would treat cancer at its fundamental cellular level. PCNA exists in healthy cells as well, but in cancer cells this protein is overexpressed, making too many copies of DNA. This allows cancer to grow and spread quickly, taking over big areas of the body. This can be observed in 90 % of cancers, which makes PCNA a perfect candidate for a target for some new drugs. Especially having in mind that PCNA rarely mutates, which means that most likely it would not develop any drug resistance during the treatment.
And so scientists set out to design a molecule that could inhibit the PCNA protein. The new medicine could potentially inhibit the growth of multiple cancers. Scientists took a fragment from an existing protein that is already interacting with PCNA and transformed it using some methods of smart chemistry. John Bruning, leader of the project, said: “Because of the special approach we have used in turning a natural protein into a drug-like molecule, it fixes to PCNA more readily and its action is specific to this protein. This is a first. It’s the first in this type of inhibitor and it will pave the way for a new class of drugs inhibiting the proliferation of cancerous cells”.
Cancer is still one of the major causes of death, despite recent scientific advancements. Attacking cancer on ground zero, on one of its most fundamental levels could make the treatment easier and more effective. Now we just have to wait until scientists put this new molecule to work in some sort of medicine.
Source: University of Adelaide