"I was delighted to take part in a clinical trial as it has the potential to really help others in the future.”
A study to understand more about how chemotherapy affects proteins and DNA
This study looked at blood samples from people having chemotherapy. The study was open to people with cancer of the
We know that in most cases, cancers of the same type can be slightly different in their make up. This is because a variety of gene defects may cause the same disease. Not everyone with the same cancer has the same gene defect or protein make up. So people may respond to treatment differently even if they have the same type of cancer.
Researchers wanted to understand more about how genes or proteins were involved in cancer development, cancer spread and response to treatment. In this study, they looked at DNA and also used new technology called Protein Chip Profiling to examine hundreds of proteins from people having chemotherapy. The aims of the study were to
- Look at any changes during cancer treatment in proteins and DNA in the liquid part of the blood (serum) and
- See if these changes reflected what was happening to the cancer
- Identify new characteristics (markers) in serum and hair follicle samples that may help predict outcome for future patients
Summary of results
The study team found changes in hair follicles, blood samples and serum samples that may help predict how well cancers of the stomach, oesophagus and bowel respond to chemotherapy.
The study recruited over 100 people with cancer. And over 100 healthy people volunteered to join.
The researchers looked at
- A protein called CK18
For the p53 gene, the researchers looked at hair follicles, blood samples and serum samples of people before each of their chemotherapy treatments. They found that they could measure the p53 gene in the hair follicles and that there was some evidence that it could also be measured in the blood sample.
For the CK18 protein, researchers looked at the levels of the protein in the blood samples of people with cancer and compared it with the levels in the healthy people. They found that the levels of CK18 were higher in the people with cancer than the healthy volunteers.
They also found that the level of CK18 was significantly higher in people whose cancer continued to get worse during, or after having, chemotherapy than in people whose cancer had stayed the same or shrunk.
For the NAG enzyme, researchers found that the levels in the serum samples increased with age. People whose cancer had spread to another part of their body (metastatic cancer) had higher levels of the NAG enzyme than people whose cancer had only spread into the surrounding tissue (
In a small number of people (a subgroup), researchers found a significant change in the level of NAG between day 1 and day 2 of the first cycle of chemotherapy. NAG levels were higher on day 2 in people whose cancer had responded to chemotherapy than in those whose cancer hadn’t.
The study team concluded that the p53 gene, CK18 protein and NAG enzyme could possibly be used by doctors to try to work out how well cancers of the stomach, oesophagus and bowel might respond to treatment. But studies with larger numbers of people need to be done to find out just how useful they may be.
We have based this summary on information from the team who ran the trial. The information they sent us has been reviewed by independent specialists (
How to join a clinical trial
Professor Jeff Evans
Cancer Research UK
Experimental Cancer Medicine Centre (ECMC)
NIHR Clinical Research Network: Cancer
University of Glasgow
Chief Scientist Office (CSO)
Greater Glasgow and Clyde Hospital Trust